Nutrient Requirements and Ration Balancing

1
Nutrient Requirements and Ration Balancing

• Forage Crops 12
• (Chapter 17)

2
Five Nutrient Classes

• Water We do not balance for water but often
  remove it
• Energy Generally measured as TDN and balanced
• Protein Balanced as crude protein - CP
• Minerals Ca and P most balanced others added
  as needed
• Vitamins

3
Converting from As Fed (AF) to dry matter (DM)
basis

• Nutrient on DM Basis Nutrient on AF
  Basis x 100
• DM
• Hay CP on DM Basis (9 90) x 100
  10
• Silage CP on DM Basis (4 35) x 100 11.4

4
Converting from Dry Matter (DM) to As Fed (AF)
basis

• Nutrient on AF Basis Nutrient on DM
  Basis_x DM
• 100
• Hay CP on DM Basis (10 x 90) 100
  9
• Silage CP on DM Basis (11.4 x 35) 100 4

5
(No Transcript)
6
(No Transcript)
7
4 steps in balancing rations

• Identify and describe animals being fed
• Select nutrient allowances (requirements
• Select feedstuffs to be used
• Determine the amounts of each feedstuff to use
  (Do the math!)

8
Steps in Balancing Rations

• Identify the animals to be fed
• Classify the animals by
• Weight
• Age
• Purpose
• Backgrounding
• Finishing
• Lactating

9
Steps in Balancing Rations

• Select nutrient allowances to fit the animals
  need
• Nutrient requirements are in Table 17.1 in the
  text

10
Steps in Balancing Rations

• Select feeds and supplements to meet nutrient
  requirements
• Pasture and hay are the least expensive base
  feeds in Tennessee (most of the time)
• Supplemental ingredients should be selected for
  nutritional value, local availability, price,
  palatability and safety

11
Steps in Balancing Rations

• Determine the amounts of each ingredient to use
• Begin by testing base forage
• Estimate the amount of base forage, then
  calculate the nutrients that are lacking
• A trial-and-error approach works for most common
  rations

12
Trial and Error Method

• Step 1
• Identify animal - Ex. 500 lb steer, 1.5 ADG
• Step 2
• Select nutrient allowances - 12.8 lb DMI 8.1 lb
  TDN 1.33 lb CP
• Step 3
• Select feeds and supplements - Fescue hay, Corn,
  Soybean Meal

13
Trial and Error Method

• Step 4
• Determine amounts of each feed

Example 1. Ration Balancing Sheet
14
Factors Affecting Nutrient Requirements

• 1. Stage of Production
• 2. Age
• 3. Size and condition
• 4. Milk Production
• 5. Weather
• 6. Length of breeding season
• 7. Breed

15
Growing Animals

• Need higher quality forages
• Good Small grains, annual ryegrass or cool
  season perennials at peak of maturity
• Not as good Warm season perennials like bermuda
  unless grazed at peak of maturity

16
Stage of Production

• One of the Major Criteria In Planning a Cow Herd
  Nutritional Program
• Consider the 365-day cow year

17
Annual Relative Nutrient Requirement of 1000 lb
Mature Beef Cow
TDN Requirements
Pd 3
Pd 1
Pd 2
Pd 4
Calf Weaned
Breeding Period
18
Cow Size and Milk Production

• 10-pound increase in milk production per cow per
  day increases the TDN and CP requirements by
  16-17 and 30, respectively
• 200-pound increase in body weight increases the
  TDN requirement by 10

19
Relationship Between Cow Size and Milk Production
20
Environmental Stress

• Plan for additional feed during cold weather
  stress
• Forages produce more heat of fermentation than
  concentrates

21
Developing Heifers for Optimum Reproduction

• Preweaning
• Select early born heifers at weaning (450-600
  pounds) depending on breed and frame size
• Weight needs to be true muscle growth without a
  substantial amount of fat
• High-energy creep feed can cause British heifers
  to become too fat and will hinder future milk
  production

22
Developing Heifers for Optimum Reproduction

• Weaning to Breeding
• Heifer needs to be grown and developed to 65 of
  mature weight at breeding
• Most British breeds reach puberty at 1 year while
  Continental breeds and some lines of British will
  be older
• Nutritional development is more critical for
  these Continental breeds and lines of British
• Typically need to gain 1-1.5 pounds/day
• Must initiate cycling prior to breeding since
  first behavioral estrus is sub-fertile

23
Developing Heifers for Optimum Reproduction

• Breeding until Calving
• Need to assure adequate growth to 85 of mature
  weight at calving
• Should gain 0.75-1 pound per day
• Adequate protein and energy is essential for
  optimum fetal growth and preparation of the
  heifer for calving and lactation

24
Developing Heifers for Optimum Reproduction

• Calving to Rebreeding
• Calving is critical time for 2-year old heifers
• Separate and monitor for difficulties
• Give app. 2 hours, then provide assistance
• The nutrient needs greatly increase due to
  lactation, growth and rebreeding
• Inadequate nutrition prolongs postpartum
  intervals and can greatly affect the future
  productivity of the heifer

25
Finishing

• Finishing on high forage diets not as widely
  practiced in U.S.
• But may be increasing, or may increase in future
• Widely done around the world in places like
  Argentina and New Zealand

26
Dairy

• Need large quality of high quality feeds,
  including some concentrate grains / protein
• Grazing dairy operations on increase

27
Deer Farming

• Most fawns born in June
• Highest quality forage needed in summer through
  September weaning
• Alfalfa, clover, chicory

28
ITS A MOVING TARGET

• Forage quality varies for many reasons, including
  seasonal changes
• Animal needs vary for many reasons
• For efficient production, forage quality should
  match animal needs
• When animal needs cannot be met by forage, be
  ready to balance ration and supplement