Developmental Stages of Lambs

Dr. Dan MorricalDr. Dan Morrical

Iowa State UniversityIowa State University

Development Stages of Lamb Digestive System

Birth - 3 weeks pre-ruminant

3-8 weeks - psuedo ruminant

8 weeks & on - ruminant

Birth: Solely dependent on milk

Composition of ewes milk:

18.2% dry matter

5-7% fat

24.7% crude protein

26.4% lactose

1400 IU / liter Vit A

15 IU / liter Vit E

Milk Yield and Composition Impact Lamb Performance

•Higher milk fat leads to increase energy intake

•ISU creep trials: 16, 21 & 26% CP

No variation in performance

•Megalac increases milk fat

Creep DietsPalatable

-Corn

-Soybean meal

-Molasses

-DDGS

-Soybean hullsRoughage is of minimal value

Lambs get adequate roughage intake from ewe diets

Creep Diets

•Easily digestible

•15-20% crude protein

•Added fat

Creep RationCorn 1470SBM 49% 370Molasses 100Limestone 40Big GainTM salt 10Ammonium Chloride 10CTC 50 gramsSelenium .2 gramsVitamin A 1,000,000 IUVitamin D 100,000 IUVitamin E 50,000 IUZinc 136 gramsCrude protein 16.7%TDN 83.4%Calcium .84%

Phosphorous .38%

Ration Physical Characterics

Very young lambs Meal form

3-8 weeks Medium grind

8-12 weeks Coarse grind

>12 weeks Whole grains

Nutrient Requirements

Factors :

Sex

Lean Growth Potential

Weight

Composition of Gain

Rams Lambs Superior

WethersIntermediate

Ewe Lambs Poorest

Mature Size

Lambs are market ready at 65% of average mature weight of ewes of parent breeds.

220 lb. sire + 180 lb. dam = 400 ÷ 2 = 200.

200 x .65% = 130.

% Protein Concentration of Lamb Rations

ADGLamb Wt. .50 .60 .70 .80 40 15.9 17.0 18.6 20.4 55 13.4 14.7 15.8 16.9 70 12.8 13.9 14.7 15.5 85 12.0 12.7 13.4 14.3 100 11.4 11.9 12.6 13.3 115 10.8 11.4 11.9 12.5

Protein Quantity and Quality

Very young lambs -

solely dependent on feed protein

for quality and quantity

Ruminant -Protein quality depends on

Feed origin

Bacterial origin

Ruminant - Protein Quantity

•Intake

•Microbial yield

-impacted by energy intake

-rumen ammonia level

-liquid dilution rate

Rumen Bacteria

Cellulolytic - Fiber digesters

Amylolytic - Starch digesters

Proteolytic - Bacterial protein digesters

Lamb Intake

Controlled by:Fill

Energy

Low concentrate diets -- fill

High concentrate diets -- energy

Specific Nutrients

Vit E. 40,000 IU/tonSe .3 ppmCa .48P .24Salt .5-1.0%

What Type of Ration

1. Targeted marketing date.

2. Relative costs of nutrients.

3. Compositional goal.

4. Facility size.

5. Feed processing equipment & storage.

6. Feeding system.

Simplest System

Whole corn: Pelleted Protein Supplement.

Advantages:

-Superior feed efficiency

-Self fed

-Low processing costs

-Low cost diet

-Acidosis risk

Simplest System...continued

Disadvantages:-Sorting

-Slower gains

-Quality of protein supplement

-Cash expense for protein pellet

High Hay RationsAdvantages:

-Minimal cash outlay

-Value added to hay crop

-Improved composition

Disadvantages:

-Lower ADG

-More facilities, bunks and pens

-Hay waste

Weaned Lamb Performance on Grass

Factors - Forage Species

Grass vs. legumes

-Age of lamb

-Health of lambs

-Condition of lambs

Lamb Gains on Straight Grass

.20 - .25 pounds per day

.35 - .50 w/pound supplementation

Conversion 1:10 to 1:5

Escape Protein for Pasture Lambs

Sources:

•Blood Meal

•Fish Meal

•Corn Gluten Meal

Nursing Lamb Performance on Grass

Milk Production is Key1. Rotational grazing

a. high quality and quantity of forage

b. reduced competition between ewe & offspring

2. Creep Feeding

a. improved growth

b. allows coccidia control

c. increases cost of production

Internal Parasite Control Strategies

1. Clean pasture

2. Clean sheep

3. Sheep age & resistance

Clean Pasturers

1. Not grazed by sheep for six months.Hay ground

Cattle pasture

2. Rotate sheep & cattle middle of growing season.

3. Turn our clean sheep to minimizecontamination.

Clean Sheep

Older sheep are more resistant.

Young lambs evaluate frequently until 6 months of age.

Treat before turn-out, retreat at 21-days.

Multiple water sources.

Coddidia Control

1. Multiple water sources

2. Ionophores in mineral ?

3. Clean out ewes prelambing

4. Clean water source