1 / 25

Nutrient Requirements of Beef Cattle

Nutrient Requirements of Beef Cattle. Outline. Nutrients Stages of production Factors affecting intake Rumen microorganisms Protein Energy Using the tables. Nutrient Categories. Water Carbohydrates Protein Lipids (fats & oils) Minerals Vitamins.

nelsonbennett
Download Presentation

Nutrient Requirements of Beef Cattle

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Nutrient Requirements of Beef Cattle

  2. Outline • Nutrients • Stages of production • Factors affecting intake • Rumen microorganisms • Protein • Energy • Using the tables

  3. Nutrient Categories • Water • Carbohydrates • Protein • Lipids (fats & oils) • Minerals • Vitamins

  4. Chemical Composition of Yearling Steers Carstens et al., 1991

  5. Four Stages of Production • Post-calving • Early lactation • 1st trimester • Late lactation • 2nd trimester • Mid gestation • Dry period • 3rd trimester • Late gestation • Dry period

  6. Dry Matter Intake is Influenced By • Weight • Condition • Stage of Production • Forage Quality • Amount and Type of Supplement Provided • Environmental Conditions

  7. 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.

  8. Forage Capacity of Beef Cows% of Body Weight

  9. 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

  10. 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

  11. Protein – Rumen MCO Increased Intake = More Energy 0 .3 .6 .9 1.2 1.5

  12. Forage Protein vs. Requirements 400 lb 500 lb 700 lb Forage Protein

  13. 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.

  14. Rumen Feed MP CP Indigestible Protein UIP DIP Small Intestine NH3 Microbial Protein NH3 Metabolizable Protein System

  15. Energy Requirements • Grazing • Movement • Fetal Development • Milk Production • Temperature Maintenance • Reproduction • Digestion • Voiding Body Wastes

  16. 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

  17. Energy Requirements • Heifers require additional energy for growth up to 4-5 years of age • Thin cows require additional energy to restore body condition

  18. 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

  19. 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

  20. 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 cows will increase the requirement for additional feed resources by 6-8%

  21. Vitamins and Minerals • Covered in detail in OK Beef Cattle Manual Chapter 14 • Table 11.7 (page 103) shows requirements and maximum tolerable amounts

  22. Nutrient Requirement Tables

  23. Water Requirements • Important Nutrient • Factors Affecting Intake • Age • Weight • Temperature

  24. 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

More Related