The Ruminant Animal Chapter 10 Oklahoma Cooperative Extension Service Oklahoma State University
Arable Land Globally: 1/32 of the land mass is suitable for cultivation. United States: United States: Today there is 1.875 acres per person. By 2025 there will be 1.25 acres per person suitable for cultivation.
Beef Cow is a Ruminant * Utilization of high fiber forage Utilization of feed co-products Inedible to Humans
* Reticulo-Rumen
Rumen Stratification of Ingesta *
Time Grazing vs. Time Ruminating
Bacterial Fermentation Process of Digestion. Rumen Bacterial Population 150 billion/tsp Located in Fibrous Mat and Liquid Layer. Over 150 Microbial Species Determined by Type of Feed, and Reproductive Rate.
Rumination * Process of rapid ingestion of forage for remastication later. Reduces particle size enhancing microbial function, and feed passage. Cud chewing produces saliva flow up to 45 gallons per day. Saliva buffers the rumen to enhance microbial growth and development.
Rumen Microorganisms Symbiotic relationship enhancing digestive processes Structural carbohydrates require fermentation * Mature forages decrease digestibility Slows Rate of Passage Nonstructural carbohydrates readily digestible * Primary bacteria are fiber-digesters, and starch-digesters
Rumen Microorganisms (cont.) * * * Volatile fatty acids (products of fermentation) provide up to 80% of the energy needs of the animal. The beef cow derives most of her protein from digestion of rumen microbes. Changes in diets should take place slowly to avoid digestive problems.
Summary Cattle are ruminants. Depend on microorganisms for protein and energy. Feeding programs should maximize microbial protein production first. Supplemental feeding programs should meet dietary deficiencies.
Nutrient Requirements of Beef Cattle Chapter 11
Nutrients Outline Stages of production Factors affecting intake Rumen microorganisms Protein Energy Using the tables
Nutrient Categories Water Carbohydrates Protein Lipids (fats & oils) Minerals Vitamins
Chemical Composition of Yearling Steers 17% 4% 24% 55% Water Fat Protein Ash Carstens et al., 1991
Four Stages of Production * * Post-calving Early lactation 1 st trimester Late lactation 2 nd trimester Mid gestation Dry period 3 rd trimester Late gestation Dry period
Dry Matter Intake is Influenced By Weight Condition Stage of Production Forage Quality Amount and Type of Supplement Provided Environmental Conditions
Dry Matter Intake Factors (cont.) * * Examples include Larger-framed cattle eat more forage than smaller-framed cattle. Capacity of the digestive tract is the single greatest factor. Nursing cows eat more forage than dry cows. Fleshy cattle eat 3-10% less forage than average to thin-fleshed cattle. Cold stress increases intake, while heat stress decreases intake.
Forage Capacity of Beef Cows % of Body Weight Forage Maturity Stage of Production Dry Lactating Low Quality 1.8 % 2.2 % Average Quality 2.2 % 2.5 % * High Quality 2.5 % 2.7 %
Protein: The First Limiting Nutrient Composed of hundreds of amino acids Provides for: Tissue growth and maintenance Immune system antibodies Blood proteins Enzyme system function Milk production Microbial synthesis Protein supply has dramatic impact on microbial activity
Feed the Rumen-Feed the Cow * Rumen microorganisms breakdown dietary protein for their own growth and development The microbes are digested in the small intestine of the ruminant Microorganisms need 7% crude protein for their maintenance and reproduction Limited CP for microbial synthesis, limits fiber digestion for the ruminant
16 Protein Rumen MCO Increased Intake = More Energy 52 Prairie Hay Intake (Lb) 15 14 13 12 11 10 0.3.6.9 1.2 1.5 Soybean Meal, Lb/Day 50 48 46 44 42 40 38 DM Dig gestibility (%)
Protein Needs of Beef Cow Protein 3 1.6 1.4 2 *30 70 % Increase 2.3 1 0 2nd Trimester 3rd Trimester Early Lactation
Protein Requirement Pro otein 2.8 2.4 2.0 1.6 1.2 0.8 0.4 0.0 Calving Weaning Req t Grass J F M A M J J A S O N D Month
Forage Protein vs. Requirements 15 Percent Crud de Protein 13 11 9 7 5 400 lb 500 lb 700 lb 15-May 25-Jun 15-Aug 20-Sep Forage Protein
Metabolizable Protein Characterizes protein degradability in the rumen, and utility in assuring optimal rumen function. Degradable intake protein (DIP) is broken down in the rumen. Undegradable intake protein (UIP) is not broken down in the rumen, but in the small intestine. Metabolizable protein (MP) is the sum of microbial-derived protein plus UIP.
Metabolizable Protein System Feed Rumen MP CP DIP UIP Indigestible Protein NH 3 Microbial Protein Small Intestine NH 3
Energy Requirements Grazing Movement Fetal Development Milk Production Temperature Maintenance Reproduction Digestion Voiding Body Wastes
Energy Requirements Key requirement factors Weight Rate of gain Lactation/fetal development Grazing cattle energy is produced from rumen digestion of forage Inadequate protein in the diet for microbial synthesis means insufficient energy produced from decreased fiber digestion
Energy Requirements Heifers require additional energy for growth up to 4-5 years of age Thin cows require additional energy to restore body condition
* Energy Terms in the Requirement Tables Requirements expressed as: Total digestible nutrients (TDN) Net energy for maintenance (NEm) Net energy for gain (NEg) TDN is the sum of the digestible starch and other non-structural carbohydrates, fiber, protein and fat in a feed with a correction factor of (2.25) for the high energy content of fat
Energy Observations * TDN is expressed as percent of diet dry matter, as well as pounds/day required Net Energy requirements are expressed as mega calories/lb. of feed, and mega calories required/day Lactation represents the greatest need for energy beyond maintenance by as much as 30 to 70% more than when dry
Energy Observations Inadequate energy for heifers during last 1/3 of gestation, and from calving to rebreeding can result in poor rebreeding performance Every 100 lb increase in mature weight of Every 100 lb increase in mature weight of cows will increase the requirement for additional feed resources by 6-8%
Vitamins and Minerals Covered in detail in OK Beef Cattle Manual Chapter 14 Table 11.7 (page 103) shows requirements and maximum tolerable amounts
Nutrient Requirement Tables Nutrient Requirements: Class Beef Cattle Manual 2008 Beef Cows Table 11.2 Pregnant Replacement Heifers Table 11.3 Growing Steer and Heifer Calves Table 11.4 Growing Yearlings Table 11.5 Growing and Mature Bulls Table 11.6 Minerals and Vitamins Table 11.7 Water Table 11.8
Water Requirements Important Nutrient Factors Affecting Intake Age Weight Temperature Intake in Gallons Temp = 60 F Temp = 90 F 400 lb calf 5.0 9.5 800 lb yearling 9.1 17.4 900 lb Lactating cow 14.5 16.2
Summary Beef cattle have specific requirements for protein, energy, vitamins, minerals, and water The nutrient requirements vary depending on such factors as: breed, gender, age, weight, stage of production, rate of growth, environmental conditions, etc The National Research Council has published information to enable beef cattle producers to determine the nutrient needs of their cattle, and design feeding regimes to meet those needs