Animal Requirements

Requirements• Tables should be thought of as a guide

• Minimum requirement for an “average” animal• Many factors affect requirements

What Affects Requirements?

• Species• Breed• Weight• Body condition• Age• Sex• Growth

• Stage of gestation• Milk production• Physical activity• Environment• Others (disease,

stress)

Requirements• Tables don’t include:• Breed• Genetic potential• Body condition• Environment, stress, disease, parasites• Feed additives, etc.

Requirements• By understanding these other factors• Can make adjustments• Month of cold weather• Moving to a hilly pasture• Excess body condition

Requirements• Have four major components:• Maintenance• Reproduction• Lactation• Growth

Maintenance• No productive functions• Breath, move, digest, keep warm, etc.

• Weight

Maintenance• What livestock animal is truly at maintenance?• Mature gelding, no activity• Mature ewe, after weaning

Maintenance

Reproduction• Stage of gestation – last third• Expected birth weight, number• Includes development of maternal tissue and fetus• Fetus has priority over maternal• Body reserves may be depleted• Deficiencies affect fertility, puberty

Reproduction

Lactation• Greatest nutrient demands

• Amount of milk

Lactation

Growth• Actual weight• ADG (growth rate)• Mature weight

Growth

Tables• DM intake is not a requirement• Used as a guideline

• Requirements both as:• Concentration• Amount per day ***