Physiology of the cow... 3 Passage of feedstuffs in the digestion channel... 3

Transcription

1 Efficient Feeding

2 DeLaval 2001 All rights reserved. No part of this book may be reproduced, in any form or by any means, without the permission from the publisher. DeLaval, ALPRO, Feedtech and Harmony are trademarks of the DeLaval Group.

3 List of contents I. Introduction... 2 II. Basic physiology... 3 Physiology of the cow... 3 Passage of feedstuffs in the digestion channel... 3 III. Nutrition... 7 Energy supply... 7 Protein supply Other nutrients Water IV. Feedstuffs Roughage Concentrates V. Practical feeding Feeding calves Feeding heifers Feeding dairy cows VI. Feeding systems and strategies Strategies Feeding systems VII. Economy Expenses in milk production How is the economy of dairy cows measured? How much can feed cost? Quota production VIII. Nutrient requirements Dietary nutrient requirements of dairy cows Dry matter intake (DMI) IX. Products ALPRO herd management system ALPRO feeding functions Feed wagons Calf feeders Mixer wagons Milk yield recording Water Vitaid Feedtech silage... 51

4 I. Introduction Feeds and feeding strategies become more and more important as the genetic quality of cows improves. A good feeding regime is the foundation for profitable dairy farming. Feeds are also the largest cost in the dairy business. The balance between the benefits and the costs of high quality feedstuff makes feeding a challenge for the dairy farmer. With this book, we would like to share some of our knowledge in this field, with the staff of DeLaval, as well as with our customers around the world. In spite of all the available research and results from experiments, the complexity of the cow s digestion system gives dairy feeding more the character of an art than an exact science. 2

5 II. Basic physiology Physiology of the cow The cow is a ruminant with four stomachs: rumen; reticulum; omasum; and abomasum. Physiology of the cow Figure 1. The cow is a ruminant with four stomachs. Reticulum Rumen Omasum Abomasum The rumen is the largest, with a volume of litres. In the digestion system there are billions of micro-organisms. They help the cow to digest and utilise nutrients in the feed. To achieve good feed utilisation and high milk yield, the bacteria must have optimal conditions. It is the bacteria that digest the feed. Feeding a cow in fact involves feeding the bacteria in her rumen. The process of fermentation takes place in the rumen and the reticulum. Fermentation is when micro-organisms ferment carbohydrates and turn them into volatile fatty acids. This process allows the cow to convert cellulose fibres into energy. Gases are produced within the rumen during fermentation ( litres per day), 20 40% of which consist of high energy methane. These gases are expelled by belching and this involves considerable energy loss. Passage of feedstuffs in the digestion channel Rumination and saliva The cow chews the feedstuff almost without any sorting, which makes her different from other animals such as pigs. After a short period of mastication, when saliva is added, the feed is swallowed in the shape of a bolus. When the cow ruminates, feed returns back to the mouth and is masticated again. It is during the rumination process that the main grinding is done. Passage of feedstuffs in the digestion channel 3

6 Why is rumination so important? 1. Mastication. The process of grinding enlarges the surface area of the feedstuff. This greater surface area helps the ruminal micro-organisms and digestive juices to break the feedstuff down. 2. Saliva is added. During mastication, large amounts of saliva are added. A cow produces between 40 and 150 litres of saliva per day, depending on the feed she receives. Roughage has the effect of increasing rumination activity, whereas concentrates reduce it. Saliva has two functions: A. Buffering. Saliva with a ph value of approximately 8.2 has a buffering effect in the rumen. This means that the saliva does not allow acid-producing feedstuffs, such as cereals, molasses, potatoes and fodder beets, to lower the ph value by too much. Figure 2. Saliva production. B. Suppressing foam. Saliva can reduce the risk of bloat as it also has a foamsuppressing effect in the rumen. Salivary glands 150 L 40 L Roughage Grain & concentrate Rumen & Reticulum The cow s rumen is like a large fermentation vat. More than 200 different bacteria, and 20 types of protozoa, help the cow to utilise the nutrients. Feeding a cow in fact involves feeding the bacteria in her rumen. When feed enters the rumen it is placed upon a layer at the rear part. The layer consists of non-digested material with a 15% dry matter content. Bacteria adhere to the feed and gradually erode the digestible material. When the cow ruminates, cuds from the front layer are eructed. Saliva is added in the mouth and through grinding, the surfaces exposed to micro-organisms become larger. The feed particles become smaller as the bacteria work and the rumination process continues. They gradually sink to the bottom of the rumen. The material now has a dry matter content of 5%. 4

7 The rumen convulses once every minute. The convulsions either belch the ingesta or bring it to the next compartment, depending on the size of the particles. The rumen and reticulum are basically one compartment, but with different functions. Compared to the rumen, the reticulum has a more logistic function: it decides if the ingesta should be brought into the omasum or regurgitated. Cuds are chewed and saliva is added Cuds placed at the rear part of the rumen Figure 3. Circulation of feeds. Cuds from the front layer are eructed Small particles gradually sink Rumen ph The ideal rumen ph value is between 6 and 7. The desired micro-organisms are able to operate within this range. If the ph value varies too much, some types of micro-organisms are eliminated, and there is reduced utilisation of the feed. Micro-organisms that digest cellulose (hay, silage, etc.) cannot work with a ph value below 6.0. If the cow is fed large amounts of concentrates, her ration should be spread over the day. When the ration is fed only once or twice a day, the result is a large variation in the ph value in the rumen. The figure below shows a schematic description of what happens when concentrates are fed to the cow twice a day, 12 times a day, or in a Total Mixed Ration (TMR). Rumen ph Frequent feeding or TMR Figure 4. Variation in the rumen ph is reduced when concentrates are fed several times a day instead of twice a day. Twice/day Time 5

8 Omasum The omasum is the third compartment. It is characterised by the presence of a large number of leaves, which provide a wide absorption surface (about 4 5 m 2 ). This surface absorbs water (30 60% of the water intake) and nutrients such as potassium and sodium. The omasum also prevents the passage of large particles through the digestive system, and may well have functions not yet discovered. Abomasum The main function of the abomasum is to decompose protein. Gastric juices, produced in abomasum, take care of this. The ph value in this part of the digestive system is 2 3. Small intestine When the feed has passed the acid abomasum it enters the small intestine. Here, the ph value increases because the feed is mixed with pancreatic secretion, with a ph value of 8. The main functions of the small intestine are: to decompose nutrients so that they can be absorbed; and to absorb amino acids and water via the intestinal villi. Large intestine The large intestine absorbs, recirculates and saves water. Figure 5. Digestion system. From Cullison & Lowry, Feeds and Feeding (1987). Salivary glands Oesophagus Omasum Abomasum Pancreas Gall bladder Small intestine Anus Mouth Reticulum Large intestine Rumen Liver Caecum 6

9 III. Nutrition Energy supply Energy is measured in Mega Joules (MJ) or Mega Calories (Mcal). In the SI system, joules should be used, although calories are also common. The factors below can be used to transform one unit into the other. 1 Mcal= 4,18 MJ 1 Kcal = 4,18 KJ Only about 20% of the cow s total energy intake is used for milk production. The cow uses the remaining 80% for maintenance and losses through heat, gases, feed and urine. The higher the milk yield, the higher the percentage of total energy intake is used to produce milk. Energy supply Did you know that... a cow needs about 5 MJ for each produced litre of milk. Total energy demand for a high-producing cow in peak lactation is about 250 MJ, or more than 20 kg dry matter feed daily. The cow s two main energy sources are carbohydrates and fat. The energy concepts of digestible energy (DE), metabolizable energy (ME) and net energy (NE) are used to describe the animal need and to formulate rations. Net energy is most widely used. Utilisation of energy consumed by a cow Gross Digestible Metabolizable Net Energy Milk Energy Energy (DE) Energy (ME) (NE) Body Tissue Figure 6. Utilisation of the energy consumed by a cow. Maintenance Heat Increment Gaseous Energy Urinary Energy Fecal Energy Carbohydrates Carbohydrates are the cow s main energy source. They are vital for maintenance, body fat and milk production. Different types of carbohydrates are transformed into different volatile fatty acids that are absorbed as energy in the rumen. Carbohydrates can be classified in many ways: for example, sugar, starch or fibre. Sugar Sugar is quickly digested in the rumen. Many feedstuffs that contain plenty of sugar, such as molasses, are tasty and can increase the feed intake of the cow. Sugar is classified as a non-fibre carbohydrate (NFC) (see figure 10). 7

10 Starch Starch is a type of carbohydrate that can be quickly digested, and is classified as a non-fibre carbohydrate. All grains and corns contain a high percentage of starch. In the corn plant, starch is stored in the corn grains (see figure 7). Figure 7. Starch is a carbohydrate that can be digested fairly quickly. It is classified as a non-fibre carbohydrate. Starch Pectin Cellulose Hemicellulose Lignin Fibres Fibres are cell-wall carbohydrates of four parts: pectin, hemicellulose, cellulose and lignin (see figure 8). Pectin is quickly fermented and has a digestibility similar to sugar. Figure 8. Fibres are cell-wall carbohydrates made up of four fractions. Hemicellulose and cellulose are available in the cell walls (see figure 8). They contain lignin, which is solid and bound to cellulose and hemicellulose. This bond makes the cellulose and hemicellulose less available for the micro-organisms in the rumen. The result of high lignin content is that the digestibility of the feed decreases. Pectin Cellulose Hemicellulose Lignin 8

11 Fermentation Sugar Figure 9. The fermentation speed of carbohydrates. Starch Cellulose Time Neutral detergent fibre (NDF) As shown in picture 10, the NDF contains cellulose, hemicellulose and lignin. In practical feeding, the NDF value is closely related to the total dry matter intake. When most of the NDF in the ration comes from immature forage and by-products, the relation to dry matter intake becomes less relevant. Acid detergent fibre (ADF) The ADF fraction contains cellulose and lignin. The lignin is a measure of the digestibility of the feedstuff. Straw has a high ADF value. Carbohydrates Figure 10. Description of the carbohydrates and their elements. Non-fibre carbohydrates (NFC) Cell wall Neutral detergent fibre (NDF) Acid detergent fibre (ADF) Sugar Starch Pectin Hemicellulose Cellulose Lignin * Rapid to medium speed of fermentation Slowly fermented Undigestible * Lignin is not a carbohydrate, but it is closely related. 9

12 Carbohydrates are fermented in the rumen and transformed into different volatile fatty acids (VFA). VFA are absorbed through the rumen wall and serve as the main energy source for the cow. The box shows the proportions of different acids when the cow is fed a normal ration. Figure 11. Carbohydrates Acetic acid, 60 70% Propionic acid, 15 20% Butyric acid, 10 15% Acetic acid is vital for the production of milk fat. A sufficient amount of acetic acid must therefore be produced in the rumen. The primary source for acetic acid fermentation is digestible fibre, which comes from early cut silage or hay. Another important acid is propionic acid. Propionic acid affects total milk yield and milk protein content. Since propionic acid is needed for fattening, it is important when feeding beef cattle. The production of propionic acid is stimulated by starch in grain, for example. Buturic acid is important for milk fat production. The production of buturic acid increases when sugar beets and barley are fed to the cow. Fat Fat contains twice as much energy as carbohydrates. The fatty acids are transported through the rumen and absorbed in the small intestine. Fat can be used to increase the energy density of the ration. When feeding high levels of fat to ruminants it is important to use protected fat, so as not to upset fermentation in the rumen. Protein supply Protein supply What is protein? Proteins are built up by amino acids. The most important amino acids are the essential amino acids: lysine, methionine and tryptophane. A lack of amino acids can be a limiting factor in milk production. The functions of protein: building and repairing tissue; growth; reproduction; and milk production. Protein supply The protein value of feed is calculated by multiplying its nitrogen content by 6.25, based on the presumption that most proteins contain approximately 16% nitrogen. 10

13 Carbohydrates Fat Micro organisms Acetic acid Buturic acid Figure 12. Protein supply. Crude protein Propionic acid Intestine Indigestible protein Rumen Degradable protein Microbe protein Undegradable protein Excess ammonia Liver Glucose (Energy) Urea Amino acids Fatty acids Minerals Vitamins Water The figure you get is the crude protein value of the feed. Crude protein represents a combination of true protein and non-protein nitrogen (NPN). The cow has two types of protein source: microbe protein and undegradable protein. Rumen-produced protein microbe protein The major part of the protein that a cow digests and absorbs is produced in the rumen by rumen microbes. When the cow reaches higher production levels she needs additional protein, which passes through the rumen and is directly absorbed in the small intestine (undegradable protein). The micro-organisms use ammonia and carbohydrates as raw materials when producing protein. Ammonia originates from two different sources: 1. Non-protein nitrogen, which is almost immediately transformed into ammonia in the rumen. Urea is a typical non-protein nitrogen. 2. Degradable protein, which is a natural protein that contains nitrogen. In order to access the nitrogen, the micro-organisms start the process of degrading the feedstuff. Ammonia is a by-product from this process. Examples of easily degradable protein sources are grass and legume seeds. The micro-organisms grow and multiply on the ammonia and carbohydrates, and when they die they become a protein source for the cow. The microbe protein passes through the digestion channel and is available for absorption in the small intestine. Undegradable protein Undegradable protein is also a natural protein that comes from feed. The protein that escapes degradation in the rumen is called undegradable or by-pass protein. It passes through the rumen and is absorbed in the small intestine. 11

14 Other nutrients Table 1. Macro minerals. Other nutrients A cow also needs other nutrients, such as minerals and vitamins. Even if every other nutritional need is fulfiled, where there is a lack of minerals and vitamins milk production will be limited. Minerals Minerals are necessary for many of the cow s significant body functions, such as water balance and milk production. Minerals can be divided into macro minerals and trace minerals. Macro minerals are needed in larger amounts than trace minerals. Macro Minerals Notes and Function Calcium (Ca) Animals need calcium for bone and teeth formation and the transmission of nerve impulses. A high yielding cow needs about 0.6 1% calcium of total DM in her feed ration. Bones serve as a source of reserve calcium for exchange with soft tissue. Phosphorus (P) The high price of phosphorus can cause a deficiency of this mineral. A decrease in milk production is a result of insufficient phosphorus. Magnesium (Mg) A lack of magnesium is not discovered until a tetany appears. Excessive levels of potassium may result in a lack of magnesium. Potassium (K) Potassium is required in large quantities. It is vital for the cow s water balance, nervous system and for milk production. Note that excessive potassium levels reduce the availability of magnesium. If the potassium content of the ration exceeds 2%, the magnesium level will require extra attention. Otherwise, grass tetany might appear. Sodium (Na) Sodium has the function of maintaining body fluid balance, osmotic pressure regulation and acid-base balance. When cows are fed a diet deficient in sodium, they will start licking and chewing various objects. Sulphur (S ) Sulphur is an essential component of protein. Trace minerals Iron Cobalt Copper Iodine Zinc Molybdenum Manganese Selenium Vitamins Vitamins are organic combines that fulfil vital functions. There are two types of vitamins: water soluble and fat soluble. The cow can produce water soluble vitamins with the help of micro-organisms. 12

15 The fat-soluble vitamins are stored in the fat and used when needed. With high production, and a limited vitamin content in feed, additional vitamins have to be provided. Fresh feedstuff contains more vitamins than stored. Some of the vitamin content is destroyed when feed is stored. The necessary use of stored feedstuffs therefore necessitates provision of extra vitamins. A high-yielding cow needs more vitamins due to the stress that comes with high yield. Important fat soluble vitamins are A, D, E and K. Water-soluble vitamins are B-vitamins. Water A high producing dairy cow may need more than 130 litres of water per day and free access to fresh water is essential for milk production. Water is needed not only for vital body functions, such as regulation of body temperature, digestion, metabolism and excretion; it also affects total milk production. Scientific trials have shown that a 40% reduction of a cow s normal water intake can result in a 25% decrease in milk yield (Allen et al., 1976). Water needs of a dairy cow Water of high quality cows are more sensitive to poor quality water than humans; Free access a high yielding cow drinks up to 130 l/day. When feeding, water requirement can reach up to 20 l/min. This places requirements on both the dimension of the water system and the number of drinking places; Temperature the optimum water temperature is 17 C (Andersson, 1984). Very low water temperatures will result in a drop in milk yield. High temperatures will also negatively affect milk yield, although to a lesser extent; and Large drinking surfaces a cow will drink most naturally from a large calm surface, such as a pool. Bowls and troughs There are primarily two ways of providing cows with water: in water bowls or in troughs. Water bowls are most commonly found in tied-up stalls. Their main advantages are that they are easy to clean and easy to find space for. Troughs are more common in loose housing. They have greater capacity and a larger drinking surface. On the other hand, they are more complicated to clean. 13

16 IV. Feedstuffs Feedstuffs for cows can be divided into roughage and concentrates. The difference between the two categories is not always obvious, but feedstuffs that contain a large percentage of fibre are normally called roughage. Roughage Roughage High quality roughage is the feedstuff that is most fundamental for a high milk yield. From a nutritional point of view, the cow can be fed only grain and concentrates, but roughage influences many other functions, including rumination. Roughage is important in dairy feeding for at least four different reasons: 1. It is a quality source of nutrients; 2. It is essential for the rumen microbes; 3. It is essential for rumination; and 4. It regulates the rumen ph. Figure 13. Long fibre particles (> 4 cm) are essential for the rumen microbes. The bacteria attach to the particles, which have to stay in the rumen long enough for the bacteria to multiply. If the fibre particles stay for a shorter time than the bacteria generation interval, the bacteria population will disappear. It is very difficult to draw general conclusions regarding nutrient content in roughage. It all depends on the type of the roughage and its maturity when cut. As the total harvest increases over the season, the nutritional value as energy and protein decreases (see figure 14). Total yield Energy content/kg Figure 14. Development of total harvest, and content of energy and protein in herbage. Protein content/kg Time 14

17 Yield lbs kg (FCM) Milk yield from Alfalfa of different maturity Figure 15. Milk yield when feeding alfalfa hay and 20% grain. The quality of the hay varies according to maturity. Pre-bloom Early-bloom Mid-bloom Late-bloom American scientists (Kawas, et al.) examined how milk yield was affected by different stages of alfalfa maturity. In the trial, 20% of grain was fed together with alfalfa hay of different maturity. By feeding pre-bloomed, instead of latebloomed, alfalfa hay milk yield increased by 35% (see figure 15). Conserve forage Hay Making hay is a drying process where moisture content is reduced to below 15%. Mature crops are easier to make into hay than immature crops, and losses are lower, but they are also of lower feeding value. Making hay is a very weather sensitive process. Some farmers use drying fans so that they can bring in the crop from the field with a higher moisture content (approximately 40%). This reduces field losses and makes the process less weather sensitive. Silage Making silage is a fermentation process where micro-organisms use available sugar to form lactic acids. Since the early 1950s in most developed countries the total quantity of forage preserved as silage has increased steadily. The advantages of harvesting forage as silage rather than hay include: Less dependence on weather conditions; More nutrients are preserved, primarily due to reduced feed loss; Increased mechanisation of harvesting, storing and feeding; A wider selection of crops able to be harvested as silage; and Silage is better suited as an ingredient in a TMR. Figure 16. Ensilage. 15

18 A successful silage programme requires consideration of a wide variety of factors, from agronomic management to harvest, storage and feeding practices. First priority stop oxidation When freshly cut grass is stacked in a heap its temperature rises. This is due to the heat produced by chemical reactions that take place within the crop. Once this heating process starts, it can rapidly speed up, mainly because the warm air produced by these reactions rises out of the heap, thereby drawing in fresh air (similar to a draught through a domestic fire). As a result, the sugars in the crop can be quickly burnt up. The first priority in silage making is, therefore, to stop the oxidation of sugars by preventing fresh air getting into the cut crop. This is achieved by compressing and consolidating the crop through rolling. After rolling, the surface of the crop should be covered with plastic sheeting to prevent air moving through the silage. As hot air is prevented from escaping, so no more fresh air is brought in. Next priority stop chemical and microbial activity Even if the flow of fresh oxygen is stopped, grass in the heap is still completely unstable because of other chemical reactions that continue. For example, protein in the crop begins to break down, producing amino acids and ammonia. Yet more seriously, bacteria and moulds that are present naturally on the grass when it is cut can rapidly multiply and begin to decompose the crop into a putrefying and nasty-smelling mass. Both chemical breakdown and undesirable microbial activity must therefore be stopped as quickly as possible, and this can be achieved either by sterilising the crop or by making it acidic. ph-drop Undesirable bacteria and moulds that are present in the cut crop are sensitive to acid, and are inactivated by low ph levels. Under controlled conditions, most green crops undergo a natural fermentation process, where lactobacilli, a group of micro-organisms, use available sugar to form lactic acid. The initial reduction in ph values from normal 6.8 down to 5.0, which is necessary for some control over the undesirable micro-organisms, does not require the production of a lot of lactic acid. Yet the lactobacilli will only produce this acid when the crop is anaerobic, hence the vital importance of preventing air getting into the silo. Lactic fermentation also gets under way much more rapidly with chopped, rather than with long, crops. Even with consolidation and careful sealing, where anaerobic conditions are established and an initial ph drop is achieved, a further reduction in ph is necessary. This reduction, in many cases to below 4.0, is needed to completely halt protein breakdown and undesirable microbial activity, and thereby ensure safe, long-term storage. However, the rate at which the ph value falls also begins to slow down, since less sugar is available for fermentation, and progressively more acid is needed to bring about every additional ph 0.1 unit decrease ph is expressed on a logarithmic scale, so it takes ten times as much acid to reduce the ph of a crop from 5.8 to 4.8, as it does from 6.8 down to 5.8. This 16

19 emphasises the importance of a sufficient sugar supply in grass to produce the required amount of acid. Figure 17. The ph drop in untreated silage and silage treated with inoculants. ph Figure 18. Bacterial inoculants with enzymes. Untreated hours Additives Several different types of additives can be used to improve the silage process. The most common are bacterial inoculants with enzymes, organic acids and sugars. Bacterial inoculants reinforce the natural process of fermentation. Fermentation is initiated by bacteria, particularly the lactobacilli that are naturally present in the crop. However, some crops do not provide enough bacteria, or the right types of bacteria, to initiate the lactic fermentation. For many years, researchers examined the possibility of adding extra bacteria to the crop. Until recently, this was of only limited success because not enough was known about the optimum types of bacteria. New research has isolated active strains of a number of bacteria, and as a result there has been a surge of interest in the development of bacterial inoculants. To be effective, bacterial inoculants still require the crop to contain fermentable sugar. There is thus interest in using specific enzymes with the ability to break down some of the crop s complex sugar to simple sugar, which can then be fermented by the bacteria. Most of today s products contain both inoculants and enzymes. A practical advantage of using bacterial inoculants is their safety. Unlike acids, they are unharmful, both for the people using them and for machinery. Research has also shown a higher level of voluntary intake of silage, and lower dry matter loss, compared to silage made without additives. 17

20 Acids When applied uniformly throughout the crop, acids cause an immediate fall in ph and complete cessation in both chemical and microbial action. Lactic acid, however, still needs to be produced within the crop in order to enable stable, long-term storing. The most commonly used acid is formic acid, though propionic acid is also used, as it is claimed to reduce surface moulding when the silo is open. The major disadvantage with acids is that the operator has to handle large quantities of dangerous liquid. They are also corrosive on the machinery used and strong effluent has to be collected and spread on the field. Sugar The most common reason for poorly-preserved silage is that the crop contains insufficient water-soluble carbohydrate (sugar), which is needed to produce the required amount of lactic acid. The idea behind adding sugar to the crop, most often molasses, is to reinforce its natural sugar content. However, the necessary volume is generally between 5 15 litres per ton of fresh crop, which is more than with most alternative additives, and this demands substantial organisation if harvesting is not to be slowed down. It is not necessary to use an additive to make good silage. But an additive can reduce the risk of problems, especially when silage is made from problem crops which are very wet, immature, cut late in the season or contain a low sugar content. Many additives can also improve the nutritional value of the silage, both by increasing the amount of silage that livestock can eat, and by changing its chemical composition compared to silage made without any additives. Figure 19. Harvesting. Harvesting Most annual and perennial crops can be used for silage. The harvest time is of vital importance for the feed value of the silage. Harvesting should be carried out at the optimum combination of yield and stage of growth (see figure 14). Failure to cut forage crops at the right stage is widespread, and the temptation to wait a few days for a little more bulk can seriously reduce crop quality. Wet crops are difficult to preserve. High moisture levels mean that more acid has to be produced to preserve the silage. Wilting the crop has many advantages: reduce the weight of the crop that has to be carted from the field and loaded into the silo; greatly improve the ensilage process and the feeding value of the silage; and reduce effluent loss from the silo. 18

21 Grass should be cut, if possible, using precision chopping, because this breaks the cell walls of the crop and makes the sugars more available for fermentation by lactobacilli. Chopping also improves grass consolidation. During every stage of harvesting and silo loading, any possible risk of contamination should be avoided. Storage system The silage pit should be as clean as possible to avoid contamination of the grass. Before the season starts, always clean the bunker or tower with a highpressure cleaner. The life span of the bunker can be extended by protecting the walls with plastic surface protection. This will also make cleaning easier. Four types of storage system for silage are commonly used: Bunker large capacity. Can be filled and emptied with conventional farm equipment; Tower silos greater mechanisation during filling and feedout, and less area for construction; Round bales lower capital investment, good flexibility; and Stack low-cost alternative, but high DM loss during storage. Feeding out Letting in air can lead to aerobic deterioration and moulding. The exposure of the silage face should be kept to a minimum and it should be moved back sufficiently quickly. As a guide, the face should be moved back 10 cm a day in cold weather, and 30 cm in warm weather. Disturbance of the face should be kept to a minimum through the use of a block cutter or shear grab. Summary Making silage is a fermentation process where micro-organisms ferment sugar into lactic acid. The grass should be cut at the optimum combination of yield and stag growth. Wilting improves the fermentation process. The available amount of sugar is critical for production of the required amount of acid. Regardless of the type of storage system, it is important that anaerobic conditions are achieved. Additives can reinforce the fermentation process and reduce the risk of bad silage. They can also improve the nutritional value of the feed. The feeding value of the forage depends on many things, including maturity, day length, latitude, temperature, soil, fertilizer, particle size, weather conditions, and how well the feeds are preserved. Many dairy cows are fed annual crops like corn silage, sorghum silage, cereal silage and annual rye grass. Other crops like millets, sudan grass, sunflowers and rape are also of importance in certain parts of the world 19

22 Pasture Pasture is utilised in many different ways around the world. Some farmers use grazing as the sole source of nutrition, others use grazing only for exercise. To make the most of grass growth, calving is often seasonally timed so that most cows are in peak production at the time of greatest grass growth. During spring growth, some of the grass can be conserved as hay or silage and be fed during seasons when there is less grass growth. Milk from grass Milk produced from grazing without buffer feeding or concentrates is generally associated with farming in New Zealand, but this method is also common in many other countries. It is a form of milk production system that is regarded as low input. Production per hectare is more important than production per cow. The production level can vary between and kg per lactation. Milk from grass and concentrates During the grazing period, cows are supplemented with concentrates, usually in the parlour or in the tied stall. Depending on the equipment, this can be done according to flat rate or yield. The production level ranges between and kg per lactation. With irrigated grass that has been grazed at the optimal stage of maturity it is possible to reach an even higher production level. Milk from grass, roughage and concentrates As the genetic potential of cows improves, grazed grass is not nutritionally dense enough to provide the cow with sufficient nutrition. Many farmers buffer feed with other roughages. This can be done by feeding the cows buffer feed along with grass, or by keeping the cows indoors at night (or day). The buffer can be a TMR or roughage and concentrates fed separately. Buffer feed is also a good indicator of how well the grass is managed. If there is a shortage of grass, the cows will eat more buffer feed. The system of buffer feeding is less affected by drought or extremely wet or cold weather conditions. Production levels range from kg to approximately kg per lactation. Grazing methods We can distinguish three forms of grazing management: 1. Set stocking, where a herd or a group of cows remain on the field over a long period; 2. Rotational or paddock grazing, where there is close sub-division and the cows are moved between different paddocks; and 3. Fold grazing, where the cows are given a ration of grass behind an electrified wire which can be quickly moved to a new position, usually at least once a day. 20

23 A more controlled form of grazing provides the farmer with better tools to manage the feed supply to cows. The rate of grass growth will vary through the season and where there is surplus grass some paddocks can be used for silage or hay. Green chop Green chop is used as an alternative to pasture. The crop is cut in the field and brought to the cow. Suitable crops are corn, grass, whole crop grain and legumes. Green chop has both advantages and disadvantages. Advantages: Better control of the animal s feed intake; and Lower feed demand due to less animal activity. Disadvantages: The crop has to be harvested each day; and Fields can be damaged in rainy weather. Concentrates Concentrates are purchased compound feeds, straights and grain. Many byproducts are also called concentrates, but it is preferable to define concentrates as non-cellulosic or low-cellulosic carbohydrates. By-products with a lot of fibre, such as sugar beet pulp and brewers grain, do not have the same effect in the rumen as concentrates. They should therefore not be called concentrates. It is important to remember that roots and potatoes have the same characteristics as starchy feeds. These ferment rapidly in the rumen. Concentrates In general, concentrate consumption should not exceed 65% of the total dry matter intake. If a cow does not get enough fibre, the result can be disturbances in the digestion system. Cereal grain Examples of grain are corn, barley, oats, wheat, triticale and rye. The characteristics of grain are: High energy content, primarily starch; Relatively low protein content; and Generally low fat content. There are quite significant nutritional variations between the different grains. Corn has less protein and fibre, but more energy than other grains. Wheat and barley have a higher energy contents than oats. Oats contain more fibre, which slows down digestion, and they also have a high fat content. All grains are palatable except for rye. Because of its poor palatability, rye should not exceed 20% of the ration s dry matter content. Large ratios of wheat and triticale may also affect palatability negatively. 21

24 Field beans and peas Field beans, lupins and peas are good ruminant feeds as they contain a high level of energy and protein. Legumes contain plenty of quickly degradable protein and therefore must be balanced with other feeds. By-products from grain The by-products from grain usually contain little starch but most of the protein and fibre fractions from the original grain. Energy content will vary depending on the processing method. Products such as wheat feed, wheat bran, oat feed, maize gluten feed, maize gluten meal and maize gluten germ meal are commonly used around the world to feed ruminants. Oilseeds and oilseed residues Many concentrates are produced from oilseeds, such as soya bean, cotton seed, groundnut, sunflower seed and rapeseed. Of these, soya bean is most common. Palm kernal, coconut, linseed, sesame and safflower may also be used, but they are less interesting in this context. The oil is usually pressed or extracted from the seed and the residues contain the protein and carbohydrate fractions. By-products from the sugar industry Molasses and sugar beet pulp are excellent feeds for ruminants. Beet pulp is the residue that remains when sugar has been extracted from sugar beets. Beet pulp has a high content of digestible fibre, which slowly degrades in the rumen. Ergo beet pulp does not have the characteristics of a concentrate. Molasses are quickly degraded in the rumen and are also a very palatable feed. However, molasses also have a high level of potassium, which can sometimes cause problems. By-products from brewing and distilling All over the world, brewers grain is a commonly used by-product. It is low in starch and contains high levels of protein. Similar products are maize, wheat or malt draff from distilleries. Protein balance To produce a well-balanced ration, it is important to mix feeds so that the ratio of degradable and undegradable proteins is optimal for the cow: (of crude protein) 60 78% degradable protein and 22 40% undegradable protein depending on production level. Feedstuffs with high levels of degradable proteins: Urea (a non-protein nitrogen); Legume silage; Grass silage; Lupins. Feedstuffs with high level of undegradable proteins: Meat and bone meal; Fish meal; Maize gluten meal; Heat-treated soya bean meal. Buying concentrates The farmer can buy concentrates as straights, blends or as manufactured concentrates. What the farmer chooses depends on the farm situation and the type of feeding system used on the farm. Manufactured concentrates can be made up of many different raw materials so as to suit the farmer s needs. 22

25 V. Practical feeding Feeding calves The colostrum period The calf is born without an immune defence system. In time, this defence develops, but until then the antibodies from a special milk, colostrum, function as the defence system. The antibodies from colostrum protect the calf against disease until it has developed antibodies of its own. Feeding calves The colostrum period is 5 7 days. During this time calves should be kept in dry, bright, and draft-free single boxes. The first drink of colostrum, 1 2 litres, must be given during the first three hours of the calf s life. From then on it should be fed twice a day, and the daily quantity should be increased by about 1 litre per day. This means that the calf s ration is 6 8 litres at the end of the colostrum period. The calf s digestion system At birth, the calf s digestion system is not yet developed. Of the four compartments, only the abomasum functions The calf is therefore dependent on milk as a nutrient source. From its third week, the calf should be fed solid feed, i.e. concentrates, hay and silage. The calf should also have access to clean water 24 hours a day. As soon as the calf is eating regularly, the milk ration can gradually be reduced. If the milk ration is reduced slowly, and solid feeds are fed together with clean water, the calf will steadily develop into a ruminant. Calf diarrhoea Calf diarrhoea is an ever-present threat to baby calves. A good programme of adequate nutrition and sanitation, and a comprehensive herd health programme, can minimize the incidence of diarrhoea and losses. Figure 20. Calf diarrhoea causes more financial damage to cow calf producers than any other disease-related problem they encounter. In the USA, approximately 10% of all new born calves get diarrhoea, usually in the first 7 10 days of life. Up to 30% of those that survive never reach their potential. Many diarrhoea cases can be directly related to poor colostrum intake by the newborn calf. The quality of colostrum intake has a major impact not only on diarrhoea, but also many other calf diseases. If a calf gets diarrhoea it should be immediately treated to stop dehydration, acidosis and electrolyte loss. 23

26 Of importance in calf feeding: A calf s daily ration should consist of 2 up to 6 8 litres of colostrum; Several small meals are preferable. This is due to the small volume of the calf s stomach (about 2 litres) and it will help the coagulation of milk in the abomasum; The temperature of sweet milk should be 38 C. Sour milk can be fed at C; and The milk must be free of lumps and always freshly prepared. Summary The calf should drink, in a natural angle, from a teat. The calf should drink minor rations, suited to the small abomasum volume. The milk should be served correctly tempered. Otherwise, there are major risks for diarrhoea. The milk ration should be reduced slowly over time. The calf should be eating at least 1 kg concentrates before the milk ration is reduced. Feeding heifers Feeding heifers The heifer can be the most neglected animal in the herd. Feeding heifers highquality feedstuffs is important since they are tomorrow s dairy cows. The goal is for the heifer to be a milk producing cow within 24 months. To achieve this she should gain, on average, about 700 g in body weight per day. During puberty (between the age of 6 10 months), the heifer should be carefully fed. At this stage there is a risk that the heifer will develop too much fat tissue in her udder if she is reared too rapidly. To prevent this, the energy ratio should be restricted (see figure 21). Heifers do well on highly-digestible pasture if minerals are added. However, they do not grow well only on straw, late cut hay or late cut silage. General rules: Feed plenty of fibre => medium growth, and a good dairy cow can develop; Suitable feedstuffs hay, legume and grass silage; and Unsuitable feedstuffs corn silage, wet corn and wheat (too much starch). Figure 21. The energy ratio should be decreased a little during puberty. Energy (MJ) Age (months) 24

27 Feeding dairy cows Feeding dairy cows Phase 1 Phase 2 Phase 3 Phase 4 Energy intake Figure 22. Milk production PHASE I the dry period The dry period takes place about 8 weeks before calving. Although milk is not produced, it is a very important period. Just like the marathon runner, the cow needs to be in perfect shape for lactation. Despite this, dry cows are often badly fed; in some cases overfed, and in other cases barely fed enough to keep them alive. For a high yielding cow, the dry period is a rest and repair period. Damages in the rumen can be repaired and the cow can prepare for the new lactation period. It is important that the cow is not too fat before calving. The dry period can be divided into two sub-periods according to the task: 1. Resting period (3 5 weeks); and 2. Transition period (2 3 weeks). 1. Resting period The energy demand during this period is low. Feed intake should only cover maintenance and pregnancy. Body condition should be watched closely. Thin cows should be allowed to fatten, while fat cows should be fed a restricted ration. Suitable feedstuffs are large amounts of long roughages (hay and ad-lib straw). 2. Transition period The transition period starts about 2 3 weeks before calving. Feed should gradually contain more nutrients. This can be achieved by increasing the concentrates ration. The purpose of transition is to make a smooth change from low nutrition feed to lactation feed with a high nutritional content, thereby improving health and production. Research shows that a proper transition period can result in an improvement of kg milk per lactation. The transition period involves: A. The rumen micro-organisms adapting from a low nutritional level to a new, rich diet; B. The papilles that absorb nutrients in the rumen shrinking during the resting period because of the low-nutrition feedstuff. The rumen needs time to adapt to the more intensive feeding during lactation. Increased nutrition enlarges the papilles and makes them more effective in absorbing nutrients; 25

28 C. The level of feeding should not be too high during the transition period, since this can lead to health problems; and D. In order to avoid disease there should be free access to good quality forage so that the rumen is well filled. The animals should also be kept where they are going to be milked after parturition. PHASE II early lactation Feeding around calving Feeding around calving is difficult. The cow is in a negative energy balance and must mobilise body fat to produce milk. It is therefore necessary to increase dry matter intake as fast as possible after calving without upsetting the rumen system. This increase is necessary to minimise the loss of body fat and restore the energy balance. If a cow looses too much body condition it may result in reproduction problems. It is also vital in order to balance the vitamin and mineral intakes and to avoid deficiencies and disruptions in production. Disturbances around calving Paresis Paresis is a paralysis which can occur one week before, to one week after, calving. The cow simply becomes paralysed due to blood calcium levels below the required level. Paresis can be prevented by feeding the cow so that she does not get too fat around calving. Laminitis Laminitis is a hoof inflammation that particularly strikes first-lactating cows. The hoof pain caused by this disease decreases milk production. Rapid changes in feedstuffs and acidotic rations (with a high level of starch) all contribute to increased laminitis. Spreading the concentrate ration over the day will help keep the ph level in the cow s rumen stable. Feeding during the first period after calving Characteristics of the weeks after calving: Insufficient feed consumption; Greatly increased milk production; and Great risk for nutritional shortage, for instance of protein and energy. During this period it is difficult to supply the cow with enough nutrients. Instead of increasing feed consumption, which is difficult during the period after calving, the concentration of nutrients can be increased. The low feed intake also results in low production of the microbial protein produced in the ru- 26

29 men. To meet the protein requirement, the amount of undegradable protein should be increased. The first lactation months Feeding during the first 2 3 lactation months has the aim of supplying the cow with enough energy. This is achieved by a high feed intake. To help the cow reach this high energy intake, some general conditions have to be established: Healthy cow climate, high levels of comfort; Feedstuffs of a high hygienic quality; and Free access to clean water. There are also some general needs regarding feedstuffs. The most basic ones are: High energy roughage This not only provides a higher concentration, but also the possibility of higher feed intake. Wilted silage is recommended due to its higher consumptionability. High-energy concentrates Concentrates should contain a lot of energy and should be chosen with care, based on structure and primary product. Fat is a good energy feedstuff in this phase of the lactation. The fat content should not exceed 5 7% of the total dry matter content. Disturbances in early lactation Rumen acidosis Rumen acidosis occurs when the cow is fed excessive amounts of grain. Too much acid accumulates in the rumen, causing indigestion and off-feed (the cow does not eat). A cow that is affected by moderate rumen acidosis milks poorly and looses weight. This disturbance may be prevented by: 1. Feeding concentrates during a steam-up period before calving; 2. Increasing grain slowly in early lactation; and 3. Correct the feeding of grain, i.e. providing many minor rations and feeding roughage before grain. Ketosis Ketosis is a metabolic disturbance that strikes high yielding cows between 10 days to 6 weeks after calving. The disease occurs when the energy output for producing milk is greater than the energy input from feed. The cow starts to utilise body fat to compensate for the loss and fulfil the demand. Toxic byproducts are the result of large-scale fat decomposition is t. This disturbance may be prevented by: 1. Keeping the cows in proper body condition; 2. A careful transition period; 3. Encouraging maximum energy intake after calving: and 4. Feeding concentrates with high fibre content. 27

30 Displaced abomasums Cows that are incorrectly fed in the first two lactation months may suffer displaced abomasums. The abomasum is filled with gases and expands like a balloon at the side of the rumen. A cow affected by the disease behaves like a ketosis cow. This means that she has a low feed consumption and her behaviour is dull. This disturbance may be prevented by: 1. Providing the cow with free access to high quality and long fibre forage in the transition period; and 2. Avoiding fine chopped silage, i.e. less than 1 /2 cm. PHASE III mid lactation Mid lactation takes place 4 7 months after calving. Characteristic for this period is the risk of overfeeding cows. The energy demand for milk production decreases and the cow becomes more likely to increase body fat. The risk for fat cows is therefore immediate. Goals when feeding in mid lactation Maintaining high production with low feed costs. Watch for cows putting on fat. Means Feed according to production. Decrease concentrates gradually. TMR with lower energy concentration. PHASE IV late lactation Late lactation takes place during the last months before the dry period. The main concern during late lactation is to achieve the body condition of the cow that she will have at calving. Therefore, overfeeding or underfeeding in relation to milk production is sometimes necessary. How to handle cows that are too fat: Decrease concentrate and forage quantity; Change to low energy roughage; and If milk yield low, an earlier dry-off than planned. How to handle cows that are too thin: Increase the quantity of concentrated forage; Look for parasites or other health problems; and Dry off the cow 2 months before calving. To dry off cows: Decrease feed suddenly, e.g. only provide straw and water. Stop milking. If possible, remove from milking cows. Check udder during first week. 28

31 VI. Feeding systems and strategies Strategies Strategies Flat rate Flat rate feeding is a feeding strategy where all cows are fed the same level of concentrates during the whole, or part, of the lactation period. The concentrates are restricted to a certain level while roughage is fed ad libitum. The cow s energy and nutrient demands vary depending on the stage of the lactation. Because of the fixed concentrates ratio, flat rate feeding relies on fat mobilisation. The surplus of nutrients in mid and late lactation is stored as body fat. The cow uses the surplus when demand is high, namely in early lactation. Fat mobilisation in early lactation can cause ketosis in high yielding cows. Cows are usually underfed during early lactation and overfed during late lactation. Flat rate feeding is common in countries with extensive milk production and large areas of pasture, such as New Zealand, Argentina, Ireland and Australia. Challenge feeding/feeding to yield While flat rate relies on fat mobilisation, challenge feeding/feeding to yield aims to supply the cow with the nutrients that are needed for the actual lactation stage. Challenge feeding/feeding to yield is common in countries with intensive milk production.the advantages are that cows can be kept in proper body condition, and that each cow is given a fair chance to show her production potential. The incentives for this are considerable. Every extra litre in peak lactation can result in a higher total yield of up to 200 litres of milk per lactation (Michael F. Hutjens). Milk yield (nutrient demand) Nutrient supply from feed Figure 23. With challenge feeding/ feeding to yield, feeding is adjusted to match milk yield

32 The strategy is divided into two phases related to the different lactation stages. I. Challenge feeding takes place in the early lactation period (marked 1 in figure 22). It involves every cow, regardless of yield, being given a maximum ration of concentrates 4 6 weeks after calving. This procedure gives all cows the possibility to show their production potential. Underestimated cows can therefore be discovered. As mentioned before, every extra litre in peak lactation can give 200 litres more milk over the whole lactation period. II. The second phase, feeding to yield (marked 2 in figure 22), takes place approximately 100 days after calving. The cow is fed to match her measured milk yield. This strategy means feeding each cow individually. Feed is saved and the risk of fat cows is reduced. In large herds, the strategy requires advanced equipment to make work and management processes easier. Phase feeding Phase feeding is a type of challenge feeding/feeding to yield. Different feedstuffs are fed in different phases during lactation. For example, this means that feed 1 is fed in early lactation, while feed 2 is fed later on, etc. In early lactation, high quality concentrates are fed. Later on in lactation, these high quality concentrates can be replaced by less expensive concentrates containing more roughage of poorer quality (see figure 24). Phase feeding can improve rumen health because better quality feeds are fed in early lactation. Phase Feeding Figure 24. Phase feeding, where the feed for high yielders fed in early lactation is gradually replaced with poorer quality concentrates and roughage. DMI (kg) Rolled grain Soya meal High quality conc. Silage Hay Lactaction month Ad libitum feeding Ad libitum feeding simply means that the animals are allowed to eat as much feed as they want. Roughage is often fed ad libitum. 30

33 Feeding systems The dominant feeding systems for dairy herds are: 1. Separate Concentrate Feeding (SCF); 2. Total Mixed Ration (TMR); and 3. Partly Mixed Ration (PMR). Feeding systems Separate Concentrate Feeding (SCF) In a SCF system, the roughage and concentrates are fed separately. The system makes individual feeding of both roughage and concentrates possible, but roughage is usually fed ad libitum and concentrates are fed restrictively. SCF in loose housing In loose housing barns, the roughage is fed ad libitum in the feed bunk, while the concentrates are provided in feeding stations or in-parlour feeders. The suitable feeding strategy for SCF with in-parlour feeders depends on the way in which the farmer can control the feeders. In some systems, it is possible to feed cows individually; in others, all cows must be fed the same amounts in the parlour. Feeding in parlour can improve cow traffic. The disadvantage is that only a small concentrates ratio can be fed. Ratios that are too large cause eating times that are too long and unhealthy for the rumen. When the stations are placed out of the parlour, challenge feeding/feeding to yield can be used as the feeding strategy. The amounts of different feedstuffs are registered in a computer. When the cow enters the feeding station, she is identified and the correct amount of feed is dispensed. A summary of advantages and disadvantages of the positioning of feeders is shown below: + In parlour Table 3. Advantages and disadvantages of feeding in parlour. Faster milking. Easier cow traffic. Concentrates can only be fed as many times as the cow is being milked (often twice/day.) The amount of concentrate is limited. Restless cows during milking. Cows dung while they eat. Risk of manure in the pit. 31

34 Table 4. Advantages and disadvantages of feeding out of parlour. + Larger amounts of concentrates can be fed due to smaller rations and more frequent feeding. Improved rumen health. Out of parlour Less efficient cow traffic. Problems with access to feeders during the grazing season. SCF in stanchion barns Separate feeding is the normal feeding system in stanchion barns. Concentrates are often fed individually, while roughage is fed ad libitum. Some farms, especially those that use phase feeding, also feed the roughage individually. The common strategy in stanchion barns is some form of challenge feeding/ feeding to yield. Total Mixed Ration (TMR) In the TMR feeding system, concentrates and roughage are mixed in a mixer wagon. The mix is often dispensed to the cow directly from the mixer wagon, but can also be distributed with conveyors or with feed wagons. The TMR system is most common in large loose-housing barns, but can also be used in stanchion barns. The TMR is often fed ad libitum, although it can also be fed restricted. TMR single ration In single ration systems, only one mix is made and dispensed. The mix is composed so as to suit high yielding cows, while lower yielding cows will eat less. The balance of the ration is very important to avoid fat cows. The system works best with high yielding herds and breeds like Holstein and Jersey. If the cows are grouped, and the high yielders are fed ad libitum, it is possible to feed only one mix, and the next group are given a percentage of the mix and ad libitum straw or hay. Dry cows may be fed a small quantity of the mix in addition to straw or hay. One of the biggest advantages in using a single TMR is that cows do not have to change feed. TMR several rations There are many ways to divide cows into groups. They can be grouped according to yield, body condition score, stage of lactation, first calf heifers and fresh cows. The feed ration can be tailored to suit the needs of each specific group. 32

35 Precision improves as the number of different groups increases. At the same time, the rationality of the system is lost. Much time has to be spent on moving the cows from one group to another as production changes. Several mixes have to be made and dispensed to the cows to suit each group. Partly Mixed Ration (PMR) Partly Mixed Ration (PMR) is a feeding regime that combines TMR and SCF. It involves a mixer wagon mixing roughage and some of the concentrates. The concentrates level is suited to low yielders. High yielders get extra concentrates in feeding stations, in-parlour feeders or from a feed wagon. When feeding more than one roughage and by-products, PMR is a very smooth way of feeding if the farmer wants to feed concentrates individually. When some of the concentrates are mixed with the roughage, feed intake increases and the risk of rumen acidosis is reduced. Situations where one or the other system is preferable: Separate feeding only one or two roughages roughage in round bales roughage in tower silos only dry feeds manufactured concentrate home produced grain small farms (less than 30 cows) TMR / PMR several roughages roughage in clamp silos roughage in tower silos (with certain adaptations) high moisture products straights home produced grains bigger farms (more than 50 cows) Table 5. Comparison between the suitability of Separate and TMR/PMR feeding. 33

36 VII. Economy Expenses in milk production Expenses in milk production The costs involved with milk production are often divided into fixed costs and variable costs. From a long-term perspective, all milk production costs are variable costs. For example, in the long run the useful life of a solid stone barn comes to an end and it has to be replaced. It is, however, convenient to regard some costs as fixed in the short, or even medium, term. Buildings are often regarded as fixed costs. The labour costs and capital costs of machinery and equipment are often interchangeable. When you invest in effective machinery, labour costs will be reduced. Feed is a fixed cost at a given level of production, but since the price varies and turnover is fast, it very often fluctuates. With different milk yields in a herd of a given number of cows, feed costs vary greatly. The relationship between different expenses in the dairy cow business can be represented as follows: Figure 25. Costs for housing and labour for feeding and milking often account for about 50% of total expenses. The major part of the other half is feed costs. Buildings, labour, etc. Relationship between expenses in milk production Concentrate Roughage How is the economy of dairy cows measured? How is the economy of dairy cows measured? Milk minus feed One of the most common ways of estimating the economy of milk production is milk minus feed. A better measure is reached if total feed costs (concentrate and roughage) are included. Often, only milk income minus the costs for bought feeds are measured. This is due to the fact that production costs for home-grown feed (including machines, cultivated area, etc.) are more difficult to measure. 34

37 The margin per cow of milk minus feed generally increases with increased milk yield (see figure 26). Margin milk minus feed Figure 26. The margin over milk income minus feed costs with increasing milk yield per cow. Milk yield per cow Costs per produced litre This measure shows the production costs per litre milk. It is a good measure, because the farmer is paid per litre. When comparing costs per produced litre of milk between different herds it is important to know the production level. A high yielding herd can have higher feed costs per produced litre of milk, but the total margin can still be higher than for lower yielding herds. How much can feed cost? The net margin over milk income minus feed costs can be altered, either by increasing milk income or by decreasing feed costs. Figure 26 shows how much you can afford to spend on feed. How much can feed cost? A high yielding herd can have higher feed costs per produced litre of milk while still maintaining the same profit. If very cheap feeds are available, it is also possible to increase profit even though milk yield is not so high. The table in figure 26 shows several ways of making a profit from milk production. Of course, the figures in the table vary depending on the milk price and the fixed costs. 35

38 Table 6. Annual margin over total Annual milk yield (kg) feed cost (CHF) per cow* * The margin over total feed cost per cow should cover the costs for: labour; interest and depreciation for building; equipment; and profit. Fixed cost per cow per year: 965 CHF. Milk price: 0.58 CHF per kg. Source: Hans Samuelsson (Svea husdjur, Sweden). In the example used to produce the specific figures in the table above, fixed costs per cow were set at 965 CHF per cow per year. This includes a replacement rate of 33%, and consequently an income of 1/3 cow to slaughter and the cost of raising 1/3 heifer. Also included is the income from 1 calf per year. Furthermore, 965 CHF covers the costs of artificial insemination, official milk recording, veterinary treatment, medicine, washing powder, service and spare parts for milking equipment, electricity, insurances, telephone and all other expenses related to the dairy business. 36

39 When the costs of recruitment, AI, vet, electricity, insurance and administration are fixed, feed costs can be monitored for different milk yields (see figure 26). You can see here that if you require a net margin to cover labour and capital costs of CHF, your feed costs must not exceed 0.23 CHF per kg of milk, if the annual production level is kg per cow. If you increase the production level to kg your feed can cost 0.25 CHF in order to reach the same margin per cow. You can also see that if you manage to get hold of cheaper feeds, so that it will only cost 0.21 CHF/kg milk, you can decrease production to kg without loosing money. Alternatively, if you manage to maintain the production level, you will make another 200 CHF per cow per year. Quota production To counteract a surplus of produced milk, many countries have a quota system. This means that each farm is allowed to produce a certain quantity of milk. When the total amount of milk is reached, other ways of improving the economy of the herd must be found. Quota production One way to adapt your production in a quota system is to increase your yield and produce your quota with less cows. Profitability calculations with increased production under a quota system most often result in increased profits with increasing production. Yet profitability increases less than a similar calculation without the quota system. It is commonly said that a quota system reduces motivation to increase the milk yield by about half. The reason is often that each increase in milk sets free the type of farm capacity that has low alternative use, e.g. harvest and storage capacity for home-grown feeds, and animal housing capacity. 37

40 VIII. Nutrient requirements The values in the table below are guideline nutrient requirements and dietary recommendations for dairy cows. Table 7. Guidelines for recommended nutrient content Source: Nutrient requirements of dairy cattle. National Research Council, Cow Fat Weight Early Dry weight gain lacta- preg- (kg) (%) (kg/day) Milk yield (kg/day) tion nant week cows Energy NEL Mcal/kg DM ME MJ/kg DM Protein Crude protein (%) Undegradable protein (%) Degradable protein (%) Fibre content minimum Crude fibre (%) Acid detergent fibre (%) Neutral detergent fibre*(%) Minerals Calcium (%) Phosphorous (%) Magnesium (%) Potassium (%) * It is recommended that 75% of the NDF in the diets of lactating cows is provided as forage. Dry matter intake required to fulfil nutrient allowances for maintenance, milk production and normal life weight gain during mid and late lactation. Table 8. Dry matter intake. Source: Nutrient requirements of dairy cattle. National Research Council, Life weight (kg) FCM (4 %) (kg) % of life weight

41 Dry matter intake (DMI) Dry matter intake is one of the key factors for high levels of milk production. Everything that is done to increase dry matter intake, especially for fresh cows, will have a positive effect on the milk production level. Dry matter intake (DMI) Factors that can influence dry matter intake: Roughage quality; Freshness of the ration; Balance of the ration; Feeding frequency; Trough space; Water supply; Management; and Weather conditions. Formulating the ration There are many different software programmes available today to help calculate dairy rations. In order to calculate the ration, and control whether cows perform as expected from it, certain basic information must be available: Available feed with dry matter content and analyses of nutrient values; Dry matter intake for individual or groups of cows; Milk production for individual or groups of cows; Milk compression for individual or groups of cows; Body condition scoring; and Health record for the herd. A ration calculation should be made every time there is a change of feed, or the cows do not perform as expected from the ration. 39

42 IX. Products ALPRO herd management system ALPRO herd management system ALPRO is a totally integrated system for production control in dairy farming. Every hour, 24 hours a day, 365 days per year, ALPRO controls feeding, records milk yields and gives you immediate access to extensive information that is important for successful herd management. Figure 27. The features of ALPRO herd management system Milking When entering a parlour, the cow is automatically identified at the gate. DeLaval milking point controller MPC manages all milking activities, cow traffic and in-parlour feeders. The processor is the brain of ALPRO system. It stores all data and has total control over milking, feeding and breeding. DeLaval milk meter MM15 weighs the milk continuously. At basic level, flow indicator can be used The transponder is the key to ALPRO herd management system. 40

43 In figure 30 below you can see the different components in the present ALPRO system. Development of the system is continuous, and additional software and hardware functions are being added all the time. ALPRO herd management system develops as your farm develops, now and in the future. Feeding In the feeding station, each cow is automatically fed with the correct feed ration. Automatic feeding in the parlour is also possible with electric or pneumatic dispensers. Both the automatic milk feeder and concentrate feeding station for calves can be built into ALPRO System. With feed wagons connected to your system, you can achieve controlled feeding of cows in stanchion barns. When connected to a PC, you can retrieve and present information from the processor in your office. 41

44 One of the major advantages of ALPRO is its flexibility. You can start, for example, by investing in a feeding system for your cows, and then add other functions later, such as milk yield recording. User friendliness is another characteristic of ALPRO system. Because it is so easy to operate and understand, you do not have to be a computer expert. Just follow the full text menus. Everything follows a logical pattern and will simplify your daily work. With almost 20 years of experience with electronics in agricultural applications, we have been able to design a system with outstanding reliability. Without entering into technical details, ALPRO electrical components are well protected against electrical disturbances, humidity and aggressive substances, important factors when choosing the system that will control the main part of your production in years to come. ALPRO makes advanced herd management possible. A cow calendar means you are able to follow the cow through the breeding and lactation cycles. It informs you of when the cow is in heat, when it is time for a pregnancy check, and so on. Everything is conveniently presented on an action list that tells you what to take care of during the day. ALPRO processor can be connected to your PC, from where you can operate the system using a windows-based user interface, and communicate with other herd management software. Computer control improves your profitability step by step, because you are able to: Start to increase the feed amount and prepare the cow for calving at the right time; Increase feed intake as fast as possible after calving and prepare the cow for maximum production; Feed according to yield and control costs throughout the lactation. New feed rations can be calculated on the basis of milk yield and programmed feeding tables; Improve your breeding performance and shorten calving intervals; React immediately if production drops, as well as find and correct the reason for this; Generate profitability calculations with margin of concentrate and feed milk ratios (very useful as a basis for your management decisions); Get all important data printed in a number of list formats, thereby providing you with a powerful management tool; and Last, but not least, ALPRO will help you get more work done in fewer work hours. The time you save can be allocated to other tasks and give you more time for important planning and follow up. 42

45 ALPRO feeding functions The philosophy at DeLaval is that a feeding system should be designed to suit the cows, instead of the other way around. In this manner, feeding can be carried out most effectively and the cows will be healthier, creating conditions for good profitability. Feed station Up to 4 feedstuffs can be dispensed per station, while the system can handle 8 feedstuffs. ALPRO feeding functions Figure 28. The trickle dispensing principle is unique and clearly one of the primary advantages of ALPRO feeding system. Regardless of the number of feeds, the system will dispense the feed(s) at a programmed speed, adapted to the cow s eating speed. The intention is that there should never be any feed left when the cow leaves the feed station, and therefore no incentives for any cow to try and force another cow out from the station and steal her ration. This results in calmer animals and less aggression in the herd. The system is also smart enough to adjust the speed of each feed so that feed composition is always constant for each individual animal. The dispensing rate can also be adjusted individually to optimise the capacity of the feeding station. Biological feeding With ALPRO continuous qualification programme, the daily ration is spread out over many feedings. The amount of feed available at a given time is related to the time that has passed since the last visit. To avoid overfeeding, too frequent visits, or cows saving too much feed from day to day, certain limitations are also designed into the system (see figure 32). Figure 29. ALPRO continuous qualification. Feed (kg) Maximum available Maximum carry over Day 1 Day 2 Minimum dispensed 43

46 Figure 30. Continuous feed qualification. An example to illustrates this: Ration Maximum Available The tap that drips makes water available continuously. How much you drink depends on how often you empty the glass. How much water you get per day is programmed by how fast the tap drips, and if you stay away too long the glass will become full and you will then loose water. ALPRO feeding programme works in a similar way, although the cows of course receive concentrate instead of water! ALPRO feed qualification is a truly continuous process. There are no inflexible start/cut-off moments when feed becomes available/unavailable to the animals. Even during a day shift, nothing disturbs the continuity of Alpro feeding and its recording of daily feed consumption. This feeding principle really does allow for cows to follow their instincts and decide when they want to visit the feeding stations. The result is no rush hours at feeding stations, higher station capacity, and calmer, more natural behaviour from the animals. Table 9. No feed left in the manger when the cow leaves the station; therefore no reason for other cows to force away those that are eating. Individual dispensing rates give higher capacity per station. The different feeds are dispensed proportionally. Calmer cows and more natural cow behaviour. High capacity (re: number of cows) feed stations. 44

47 In-parlour feeding Dispensers can be connected to the system to provide easy control of automatic feeding in the parlour. When linked with automatic identification, the operator can dedicate his time to the milking work. Figure 31. The ALPRO system keeps a record of all feed intake, information that can be presented on screen or printed out. For more accurate analysis, ALPRO can determine margin of concentrate per cow or for the whole herd. Feed wagons Rail suspended feed wagons can be used in stanchion barns to feed concentrate automatically and up to 10 times a day. As mentioned earlier, distribution of the concentrate over several feedings gives a more stable ph-value in the rumen. This improves feed utilisation, animal health and gives higher yields. Experiments show that milk yield can increase by 5% or more if concentrate is fed 6 times per day instead of twice. DeLaval s product range includes several different feed wagons. Feed wagons DeLaval feed wagon FCC380 is the smallest wagon and is designed for smaller herds and barns with narrow passages. Figure 32. The concentrate is dispensed by volume and DeLaval feed wagon can handle 2 or 4 different feeds. The larger DeLaval feed wagon FM460 wagon dispenses by weight and offers very high accuracy for all types of feed. It can handle up to 8 different feeds. Figure 33. The feed wagon does not only provide possibilities to increase yield, it also makes work easier and saves time. Instead of feeding the cows, the dairyman can spend more time on the important task of herd management. 45

48 Figure 34. All feed wagons can be delivered for use with a stand alone computer, or in versions controlled by ALPRO System. The latest version provides the first stage in a system for stanchion barns and offers many exiting possibilities. Table 10. Calf feeders Figure 35. Main advantages of a feed wagon Less labour. Better utilisation of time. The dairyman can spend time on improving herd management rather than on overseeing feeding. No personal influence. Feed rations are always the same, no matter who is working in the barn. Healthier animals. Less risk of metabolic diseases. More milk, due to better feed utilisation. Lower feed costs. Exact dispensing will in most cases reduce overfeeding. Calf feeders A calf feeder feeds the calves automatically with milk from an artificial teat. They are therefore fed in a biologically correct way, just as if they were suckling their mother. The ration can gradually be increased, according to growth, and decreased, when the calves need to be weaned. 46

49 The calf feeder saves both milk and labour. With this equipment you are no longer tied to scheduled feeding times, and your can forget the heavy work of carrying and cleaning buckets twice a day. Figure 36. The critical weaning period is also facilitated by the calf feeder, and the transition into a ruminant proceeds smoothly, without growth disturbances. A concentrate feed station will help calves to develop their rumination, as well as providing further cost saving potential by reducing their consumption of milk replacer. Calf feeders from DeLaval are sold in several designs, and are able to feed milk replacer mixed with water, fresh milk or sour milk. The calf feeders can be delivered as stand alone units or linked to ALPRO System. Table 11. Main advantages of a calf feeder Less labour. Relief from scheduled and heavy work. Reduced feed costs. The milk is always served fresh and at the correct temperature for optimal feed utilisation and animal health. Keeping calves in groups allows them to behave more naturally and provide better animal welfare. Continuous control of feed consumption and health. Hay and concentrate consumption begins earlier. The calf s development into a ruminant is made faster and without growth disturbances. It becomes easier to utilise all available building area, and layout becomes more flexible. Total area and stall costs can also be reduced. 47

50 Mixer wagons Figure 37. DeLaval mixer wagons DeLaval mixer wagons use a well proven design involving 3 augers. This enables an even and homogeneous mix of the different feedstuffs. The main auger is equipped with special knives, enabling it to cut long straw and hay easily and to blend these feedstuffs into the mixture. Filling is normally done with a front loader or transport augers to add grain and concentrate from silos, for example As optional, the wagon can be delivered with a milling roller that enables efficient filling from bunker silos. If the feeding table is suitable for driving, the ration is dispensed to the cows or heifers directly from the discharge elevator. If not, conveyors or smaller feeding trucks can be used. With a mixer wagon you can utilise cheap feedstuffs and by-products such as brewers grain, bread, molasses, etc. Feeding a total mixed ration can also increase the feed intake and reduce the risk of ketosis. Milk yield recording Milk yield recording No matter which feeding system you choose, to achieve correct and optimal feeding it is crucial to know each cow s production as well as variations from day to day. Figure 38. DeLaval Milk Meter MM4 in the parlour enables you to measure the exact yield from each cow. The milk is weighed with a high degree of accuracy and the data is transferred and stored in ALPRO System. This data can later be accessed and processed to provide a good basis for your decisions regarding feeding and herd management. 48

51 For stanchion barns, the milk yield indicator will provide you with valuable information, at the same time as it controls the whole milking process. Advantages of milk yield recording Feeding can be conducted according to yield. When the cow gradually decreases its production, concentrate ratios are reduced to save feed and avoid fat cows. Sudden drops in production are discovered and can be corrected early to minimise loss of production. The yield is controlled every day. Production from high yielding cows varies by ± 6% per day. If recording is made on a day when production is low, the cow might be underestimated and, in a worst case scenario, not get the feed she needs to maintain production. Table 12. Water DeLaval water bowls and troughs are designed to be hygienic, provide large drinking surfaces and high flow rates all to accommodate the cows natural drinking behaviour. Water Figure 39. Bowls When comparing different bowls, you should pay extra attention to the drinking surface and the drinking valve. Cows like to drink from large, calm surfaces. The size of the bowl is therefore important. Dania and Colorado drinking bowls have a very large drinking surface, specially suited for milking cows. The drinking valve should provide a gentle stream of water, but at a high flow rate. The valves in DeLaval water bowls are designed to fulfil these conditions. The ideal situation is one water bowl per cow. Trials show that where there are shared bowls, the dominant cow will drink both more often and a greater volume of water. It will also produce more milk (Andersson, 1984). In loose housing stalls, the bowls should be placed over the feeding table. Water demand is greatest in connection with eating. 49

52 Figure 40. Figure 41. Stainless trough Troughs In a loose hosing stall, it is essential that water is easy available and that there is a sufficient number of troughs. The troughs should also be positioned so as to avoid dirt and manure being mixed up with the water. The Oasis energy free water trough has a thick insulation layer which keeps water cool and fresh in hot climates, and maintains water temperature in cold conditions. It should be placed on a special concrete platform to avoid dirt and manure getting into the water. The stainless steel trough is a good solution for the loose housing stall. It has the particular advantage of being easy to clean. Figure 42. Pasture On pasture, special attention should be given to the hygienic quality of the water. Cows are more sensitive than humans to bad water. It is therefore important that they are given the same quality of water on pasture as in the barn. The water should come from a fresh source and the bowls/troughs should be designed to avoid bacterial growth. Temperatures on pasture are often high and favourable for bacterial growth. Oasis water troughs are once again a perfect solution. They can keep the water fairly cool even at very hot temperatures. The water bar with 6 water bowls assures access to fresh water on the pasture. It is also easy to move around with the cows. Vitaid Figure 43. Vitaid Vitaid nutritional aid products will help improve the performance, and maintain the health, of the dairy farmer s animals. This product range includes Vitaid Electrolyte and Vitaid Balance. 50

53 Vitaid Electrolyte If a calf gets diarrhoea it should be treated directly with Vitaid Electrolyte. This product has been carefully selected to ensure the optimum benefits in the treatment of calf diarrhoea. Vitaid Electrolyte includes: Sodium and potassium to effectively replace the lost electrolytes; Dextrose to give the calf energy; Polysaccharide a gelling agent that stops diarrhoea within 24 hours and absorbs harmful bacteria in the gut; B Vitamins calves cannot produce B vitamins themselves. In the preruminant stage, they get vitamins from their mother s milk, which they cannot take during a period of diarrhoea; and Sodium citrate corrects acidosis and the altered acid balance caused by lost bicarbonates. Vitaid balance Vitaid balance is a probiotic paste that includes different species of living bacteria. It works by covering the inside of the intestinal wall with a biofilm of adhering heat-killed bacteria, thereby protecting the wall with pathogenic micro-organisms. Vitaid balance is given directly in the mouth and alters the intestinal microflora so that is more favourable. It should be used as a preventive for:older animals in periods of stress (during moving, feed changes, etc.); and- Newborn calves, to enable a good start in the build up of the intestinal flora. Very often the farmer recognises that a calf is going get diarrhoea, sometimes even 24 hours before the disease actually occurs. In such cases, one single dose of Vitaid balance solves the problem. Vitaid balance should also be used after the calf has recovered from diarrhoea to enable quick re-establishment of the intestinal rumen. Feedtech Silage Feedtech Silage is a unique combination of lactic acid bacteria, selected from grass, and specific enzymes. It can be used on fresh, wilted and baled crops and in a wide range of climatic conditions. Feedtech Silage Figure 44. Lactic acid bacteria Feedtech Silage contains four strains of bacteria that have been carefully researched, identified and selected for their ability to improve silage quality. This unique combination works to rapidly ferment the sugars in the crop to lactic acid. The result is a rapid decrease in ph to a low level. Feedtech Silage adds a million of these bacteria to every gram ensiled, enabling total control over undesirable, naturally-occurring bacteria. The growth of spoilage organisms, such as moulds, yeasts and Clostridia, that are capable of producing spores, foul-smelling ammonia and butyric acid is thereby inhibited. 51