Overview of Principles on Game Nutrition HINNER KÖSTER

Transcription

1 Overview of Principles on Game Nutrition HINNER KÖSTER

2 Introduction Profitability of modern intensive game farming practises affected by: Reproduction Amount of offspring produced within a specific specie s reproduction cycle Performance of offspring Milk production of dams Growth after weaning Phenotypic condition and features of animals Body condition, hair coat Health, immune system Legs, feet (hooves), horn size

3 Introduction Game have survived Southern Africa's harsh and variable environments Able to have migrated from one area to another Found indigenous vegetation of high nutritional quality Supplied their requirements for growth and reproduction Grass, shrubs and bushes

4 Introduction Modern times these migration routes have been largely fenced off Preventing animals from being able to move to areas where the grazing or forage would be better Selection limited especially during the drier season Game farmer/manager now has the responsibility to supply the animals with the nutrition they may need at different times of the year

5 Introduction Habitat quality determines wildlife population sizes Survey types and quality of grasses, shrubs and bushes that are present in the area Understand the variety of factors that have a direct effect on the availability of nutrients in natural forages

6 Introduction Determine carrying capacity separate for grass and leave consumers Nutrient levels together with the density of forages determine the grazing capacity of an area or camp Manage wildlife populations and their habitats more intensively Good measures of nutritional status are needed To evaluate the ability of habitats to support a given number of animals Body condition, reproductive performance, etc

7 Introduction Many written records of foods consumed by a variety of game species No chemical evaluation of dietary constituents No assessment of utilization Only provides a partial basis for applied feeding programmes Most wild animals are selective about what they eat Will not eat all acceptable foods they come across Dietary choices of free-ranging wildlife are complex Animals use a wide variety of morphological, physiological, and anatomical adaptations to acquire and utilize foodstuffs

8 Relate nutritional properties of food sources selected or avoided in nature Provides useful guidelines in developing more appropriate diets for some game species in confined areas Broad knowledge of the types of food wild animals consume and their requirements Consider Approach when developing diets for wild animals Dietary habits in the wild Oral and gastrointestinal morphology and physiology Needs of similar domestic species whose requirements are known Environmental features that affect energy and nutrient need

9 Approach when developing diets for wild animals Oral anatomy and gastrointestinal tract morphology have a high correlation with natural diet Presence of a ruminoreticulum Qualitative nutrient requirements are similar to those of cattle and sheep Gut has a cecum and sacculated colon Capacious enough to support microbial fermentation Nutrient needs are likely to be similar to those of the horse A simple stomach with limited lower gut space for microbial activity Similar to a pig (Ullrey, 1988) Can extrapolate nutrient requirements from domestic species with known needs to wild species Similar in dietary habits and gastrointestinal structure and function

10 Approach when developing diets for wild animals Beyond food habit studies, wildlife biologists have used captive animals Made detailed studies of nutritional needs Associated with physiological functions such as growth, reproduction, and horn development Relationship between nutritional status and reproductive rate is thoroughly documented Good to know what the reproductive response of animals to improvements in the supply of selected nutrients is Animals in good physical condition generally have higher rates of reproduction More resistant to all forms of mortality than are animals in poor condition

11 Approach when developing diets for wild animals The use of captive animal feeding trials to estimate the requirements of the free-ranging animal poses many questions Maintenance energy requirements of captive animals often below (25-100%) what might be expected under free-ranging conditions Activity and thermoregulatory requirements much higher for free-ranging animal Heavily grazed areas Requiring extensive food searching activities In severe continental climates Requiring an increased thermoregulatory expenditure

12 Body condition Good indices of nutritional status are measures of fat stores (body condition) Fats are the primary mode of storing energy in vertebrates Play important roles in reproduction, migration, and thermoregulation

13 If it's impossible to migrate or the whole area is in a drought the animals will lose condition

14 EFFECT OF WEIGHT LOSS ON ESTRUS-ACTIVITY IN BEEF CATTLE (Adapted from Louw, Thomas & Lishman, 1988) KT = 2,77* *CS = Condition Score Weight loss = 103 kg (21%) KT = 1,72 KT = 2,23 Resumption of Estrus Activity Weight Increase = 47kg (13%) Estrus Activity stopped

15 Horn growth Heritability of Male Horn Volume = 0.32

16 Canadian Researchers assessed the effects of resource availability on body mass and horn growth of bighorn rams at Ram Mountain, Alberta, Canada over 30 years They showed: Horn growth was positively correlated with feed availability Compensatory horn growth does not occur

17 Alpine Ibex University of Zurich (2015) measured 8043 Ibex from 1967 No evidence was detected for compensatory horn growth Late-life horn growth was positively depended on early-life horn growth in males Horns are dead tissue with no blood flow Require continuous levels of sufficient nutrition Horn growth rates continuously increased due to earlier and higher spring-time temperatures

18 Nutrient requirements of game

19 Nutrient requirements of game Most herbivore game species on farms are ruminant animals Exception: zebras, rhinos, hippopotamus, elephants, bushpigs, warthogs Differences in eating habbits and alimentary tracts of game within the same environment Makes supplementation aimed at the same specie impossible Supplementary feed for game still based on requirements of similar domesticated animals (cattle, sheep, horses, pigs) Response of such domesticated species to spesific supplemental feeds in a specific area to achieve a specific performance target

20 Nutrient requirements of game Game species would (in the habitat to which they are adapted) select a diet With a digestibility in accordance with their feeding habits and are thus classified accordingly (Hofmann (1973) Bulk and roughage grazers Large, essentially grazing animals Not high degree of selection Capacious stomachs normally filled to capacity Relatively low-quality feed composed mostly of grass

21 Nutrient requirements of game Browsers (Selectors of juicy, concentrated herbage) Feed mostly on the leaves, flowers and fruits of forbs, shrubs and trees (Concentrated food) Small stomachs (usually <200 kg mean individual live weight) Include grazing animal which exercises some form of extreme selective defoliation (white rhino - area selection) Normally filled to only 50-60% of their capacity Intermediate feeders (herbivores that eat both grass and leaves) Have the ability to adapt in different seasons and places towards grasses and leaves Have greater ability to tolerate variations in the quality of their diet

22 Grass Selection intensity Leaves

23 Factors affecting nutrient levels and quality in natural forage Every game farm or reserve has a unique system Either intensive or extensive camps Game need a particular amount of nutrients Correct ratios at different levels during the physiological changes of their life Lactation, pregnancy, maintenance, growth, etc. Specific but different daily nutrient requirements for: Protein, energy, macro- and trace minerals and vitamins Certain natural forages may be suitable for some animals but not for others

24 Supplementation Nutrients that can in particular be limited on low-quality pastures: Energy Especially where pastures have been deteriorating and competition of game increases Droughts Protein Rumen Degradable Protein in ruminant game Especially to utilise low-quality pastures and shrubs during the dry season Minerals and trace minerals (all species) Most areas require supplementary minerals and trace minerals throughout the year Roughage (all species) High quality roughage supplementation (e.g. lucerne) would supplement roughage, protein, energy and certain mineral shortages

25 Economic feeding strategy for breeding game on pastures Ensure optimal feeding conditions: 1. For maintaining live weight and condition during the dry, pregnant phase Supplementation before calving/lambing can have a larger impact on pregnancy % than supplementation after calving/lambing (Marston et al., 1995) 2. During breeding season 3. Shortly before calving/lambing (late pregnancy) 4. When calve/lamb suckles (lactating animal) Maximize use of nutrients in natural and established pastures/stover/hay/silage 1. Supplementation must complement roughage source 2. Critical to understand the effect of supplemental nutrients on the intake and digestion of the roughage source Low quality roughage goal to increase intake and digestion

26 Why supplementation? Supplementation focuses on supplying animals with the necessary nutrients that the forage available to them cannot supply Supplementation is critical to ensure Optimal degradation and digestion of available forage Prevent nutrient imbalances Improve/maintain condition score, production and reproduction The most important facet of ruminant feeding Understanding the nature and behaviour of the microbial population in the rumen during the different climatic seasons Focus on feeding the rumen microbes Ensure optimal intake and degradation of dry forage/ roughage

27 Animals that do not receive any supplementation during the dry season Intake of forage is ±0,3-0,5% less of their live body mass (DM basis) than animals that receive supplementation during the dry season Intake of forage in wetter months is: ±0,3-0,5% more of their live body mass (DM basis) than animals that receive supplementation during the dry season

28 Dietary crude protein A B1 B2 B3 C Pep NH 3 AA urea NH 3 MCP

29 Supplemental nutrition on dry pastures Dry pastures, standing hay, stubbles, stover Contains insufficient protein first limiting Insufficient protein for rumen microbes, especially where no green material is present Microbes take >48 hours to degrade the available forage Decreased supply of nutrients from the rumen to the rest of the animal's body Animal mobilizes stored reserves (e.g. fat and protein) Produces energy for survival Results in loss of condition and muscle mass Low digestibility Proper digestion of consumed material cannot take place Results in lower intakes and digestibility values

30 Requirements and Intake Governed by Metabolic BW (W 0.75 ) and not BW per se Within a feed type, small animals eat more on a BW basis than large animals

31 Maintenance Energy Requirement (all species) Based on non-pregnant, mature female 0.55 MJ ME/kg W 0.75

32 EXAMPLE : INTAKE CALCULATION Buffalo female, 530 kg BW, maintenance W 0.75 = = kg W 0.75 MER = kg W 0.75 *0.55 MJ ME/kg W 0.75 = MJ ME/day Feed quality (ruminant, grazer) = 7.4 MJ ME/kg 88% DM = 6.51 MJ ME/kg AF Feed Intake = MJ/6.51 MJ/kg = 9.33 kg FI (% BW) = 9.33 kg/530 kg * 100 = 1.76% Intake for other objectives relative to maintenance For growth & general well-being = +10% (1.75% * 1.1 = 1.9% BW) For lactation = +30% (1.75% * 1.3 = 2.3% BW)

33 Total DOMI, g/kg BW.75 Estimating RDP Requirements using the One Slope, Broken-Line Model (Köster, 1996) Forage DIP = 53% RDP Requirements = 4.01/36.15 = 11.1% of DOM Total DIP Intake, g/kg BW.75 Breakpoint = kg animal = x 4.01 = x 4.01 = 443 g RDP/day

34 RDP requirements and supplementation of game on low quality pastures Assumptions: Animal: Dry pregnant buffalo Weight: 530 kg Forage quality: 5% CP (AI basis) Degradability of CP from grass: 55% Grass intake: 9.3kg Requirements: kg x 4.0 = x 4.0 = 443 g total RDP/animal/day

35 RDP requirements and supplementation of game on low quality pastures RDP from grass: Grass intake: 9.3kg Total CP intake from grass = 9.3 kg x 5% = 465g RDP intake from grass = 465 g x 55% = 256g RDP that needs to be supplemented to optimize utilization of the grass: 443g total RDP/cow/day - 256g RDP from grass = 187g RDP/530 kg animal/day from supplement

36 Effect of different levels of urea on True OM Digestion of hay in the rumen Cattle (Köster, ) True OM digestibiltiy, %

37 Effect of different levels of urea on DOMI of hay in the rumen Sheep (Nolte, 2001) Hay DOM intake, g/kg BW % N from from Urea

38 Urea supplementation of game on low quality pastures Larger ruminants CP can be derived 100% ex NPN Game preferably 75-80% Small ruminants >25% of CP as NPN Not effectively used but still safe Non-ruminants NPN not useful Yet not lethal Zebras grazing in a mixed species camp Dietary protein deficit not covered by protein supplements ex NPN Yet not lethal

39 Supplemental nutrition on green pastures Sufficient protein Sufficient protein for rumen microbes and often also to maintain certain level of animal production Microbes take ± 12 hours to degrade the available forage Supplementing low degradable protein to maintain higher production Lactating animals, pregnant young animals, growing animals Can result in positive response Depends on performance target and economy Problem: Mainly Minerals

40 Effect of different types and levels of energy on digestible OM intake of low quality hay (Le Roux, 2002) Hay DOMI, BW ,8 34,2 36,9 Starch Cellulose Sucrose 1MJ (Maize) (Bran) (Molasses) ME/d 34,3 33,6 7MJ ME/d Energy types Energy levels RDP = 4.67 g/kg BW 0.75

41 Energy Supplementation on low quality pastures and/or roughage Feed grain and other energy sources if: Goal of energy supplementation Achieve additional production above maintenance on pastures Production licks/blocks or pellets/self mixed feeds Female animals with calves/lambs in winter Dry, pregnant female and male animals at any stage not in optimal body condition Young animals

42 Mineral and Vitamin supplementation

43 Minerals Required in small quantities Essential for all physiological systems Especially critical for growth, reproduction, milk, development, immunity, enzyme functions, cell regulation, etc. Subclinical shortages biggest problem More important than acute problems There are no symptoms beyond an inexplicable drop in reproduction efficiency, growth rate or condition score This makes the identification of which mineral it is that is deficient very difficult

44 Minerals are devided in two groups: Macro minerals (>100 ppm) Minerals Larger amounts required especially for growth (bones, teeth), nerve transmissions, water balance in the cells, etc. Calcium, phosphorous, magnesium, potassium, sodium, chloride and sulphur Calcium, Iron and Sulphur must not be supplemented in access in licks Antagonism - water Micro minerals or trace elements (<100 ppm) Much smaller quantities required and used all over body Iron, manganese, copper, zink, selenium, cobalt and iodine

45 Organic vs Inorganic trace minerals Bio-availability Organic sources high Inorganic sources differ substantially Reduced interaction (antagonistic) problems with organic sources Organic substantially more expensive Supplement selectively Normally not required for grazing animals With problems like arthrosis, hoofs (horn growth), reproduction, etc., also strong consideration

46 Hoof Integrity, Horn Growth, Skin Health and Reproduction Cu and Zn especially are important for strengthening hoofs and stimulating horn growth Organic Zn is especially used world-wide to improve hoof integrity of livestock Zn is also used: Proper keratin formation Important for wound healing, skin health, hoof/horn structures Limtation of Zn in male animals Spermatogenesis, Inhibits maturing of spermatozoa, Atrophy of the semen carrying tubes, Testicle size, Libido, Retards puberty

47 Vitamins Important vitamins needed by herbivores are: Vitamin A, D, E (Browsers), K, B12, Thiamin, Niacin, etc. Most of the deficiencies have been detected in captive animals Free-ranging wildlife continually adapt their food habits to avoid diets deficient in one or more of the vitamins

48 HOOF INTEGRITY AND HORN GROWTH Biotin Safe water soluble B vitamin Very important in growth and strengthening of the cartilage in hoofs and horns Supplementation in game: Directed towards strengthening hoofs and horn growth Achieving maximum hoof strength and horn length

49 Supplementation Raw materials and supplementary feed sources must be selected and composed to benefit all species in a specific area Must also attract game so that sufficient quantities are consumed Any supplementary feed will not improve the feed status if the pastures are not properly managed

50 Future Directives A combination of basic and applied research is essential Conducted on both free-ranging and captive animals A cross-disciplinary approach must continue Combine qualitative information on natural feeding habits with quantitative data on food nutrient composition and utilization Can provide direction for further development of optimal diets for captive/confined game animal management

51 Thank You

52 % of BW - Smaller rumen - Smaller omasum - Larger reticulum - Larger liver - Larger salivary glands - Shorter alimentary tract - Larger colon - Faster flow rate - Faster fermentation - Large rumen - Large omasum - Smaller reticulum - Smaller liver - Smaller salivary glands - Longer alimentary tract - Smaller colon - Slower flow rate - Slower fermentation

53 Nutrient requirements of game Grasses, shrubs and bushes represent basic diet of different species Oryx, Springbuck - Sweet grass Red Hartebeest and Buffalo - Mixed grass Wildebeest and Zebra - Shorter pioneer grasses Blesbuck and Sable - Sower grass Kudu and Eland Leaves Interaction between species exists Especially during drought Cattle combine well with leave consumers

54 Critical to know what the water quality is Some ingested minerals may never be absorbed Antagonism with other minerals in the water component found in the rumen One of the most important reasons being an imbalanced ratio of minerals being fed to the animal On game farms /reserves that have water that is high in calcium (hard water) A balanced combination of minerals can be fed into the animal Some of the minerals may still not be absorbed due to the antagonism found between the supplied mineral and the calcium salt in the water

55 Summer Winter Supply from pastures Protein Requirement Oct Oct

56 Summer Requirement Winter Phosphorous Supply from pastures Oct Oct