sheep/goat nutr

Sheep and Goat Nutrition and Feeding

Learning Objectives

  • Understand why sheep and goats are nutritionally unique among ruminants.

  • Understand forage selection preferences among sheep and goats compared to cattle.

  • Understand the principles of multispecies grazing and how they can be managed to control noxious weeds.

  • Know the principles involved in feeding breeding females.

Unique Aspects of Sheep and Goat Nutrition

  • Nutrient Requirements: Encompass wool or hair growth, in addition to maintenance, growth, reproduction, and lactation.

  • Voluntary Dry Matter Intake:

    • Sheep: 2.5 to 4.0% of body weight.

    • Goats: 3.0 to 5.0% of body weight.

    • Cattle: 1.5 to 3.0% of body weight.

  • Reproductive Traits: Multiple births are commonplace.

  • Forage Utilization: Historically, sheep and goats are the most effective users of low-quality roughage.

  • Biological Control: In many circumstances, they are effective biological controls for noxious pasture weeds.

  • Market Seasonal Trends: The market for mutton, lamb, and goat meat is seasonal.

Goals of Sheep and Goat Production

  • Desired Production Levels: Must identify the desired level or state of production, including:

    • Meat for specialty markets.

    • Wool or mohair production.

    • Milk and cheese for specialty markets.

    • Custom pasture improvement.

Sheep and Goat Diets

  • Forages Usage: Forages are used extensively; kids are typically grown to market weight on forage. Lamb finishing involves modest grain feeding.

  • Regional Focus: Lamb harvest is seasonal and concentrated around holidays.

  • Feed Efficiency: Rate of gain and feed efficiency are of minimal importance explicitly in sheep and goat diets.

  • Production Systems: Sheep and goats are most often maintained in range- and pasture-based production systems, focusing on grazing, leading to qualitative management of nutrition rather than quantitative.

  • Nutrient Requirements Management: Production cycles are planned to maximize use of high-quality forages during periods of peak nutrient requirements; supplementation provided when pasture forage does not meet 100% of nutrient requirements.

Pasture Management for Sheep and Goats

  • Stocking Rate: Most important aspect of pasture management based on intake.

  • Animal Class Equivalents:

    • 1,000-lb Cow + Calf: 1.00

    • Calf: 0.60

    • Yearling Calf: 0.80

    • Mature Horse: 1.25

    • Mature Sheep: 0.20

    • Lamb: 0.15

    • Mature Goat: 0.15

    • Kid Goat: 0.10

Selection Preferences of Grazing Livestock

  • Cattle and Horses: Prefer grasses > forbs > browse.

  • Sheep: Prefer forbs > grasses > browse.

  • Goats: Prefer browse > forbs > grasses.

  • Multi-Species Grazing: Minimal overlap in selection preference allows for multi-species grazing; pastures with diverse forage bases support full stocking of 2 to 3 species of livestock, thus generating multiple income sources without increasing pasture acreage.

Noxious Weed Control

  • Distinct Forage Selection: Grazing sheep and goats have forage selection preferences that differ from cattle, allowing for control of aggressive pasture weeds. These forages are nutritious for sheep and goats.

  • Revenue Generation: Sheep and goat producers can create a revenue stream through pasture improvement while eliminating seasonal pasture costs.

Multi-Species Grazing Caveats

  • Market Access: Must provide access to multiple markets.

  • Fencing Requirements: Significant barriers to goat production.

Predator Control

  • Importance: Predator control is essential in sheep and goat management.

  • Methods: Includes the use of guard animals and predator collars that poison attackers.

Nutrition of Breeding Females

  • Reproductive Cycles: Sheep and goats are seasonally polyestrous, with estrus cycles occurring every 17 to 20 days from July to January, dependent on photoperiod. Gestation lasts approximately 150 days.

  • Management Opportunities: With intense management, 3 lamb or kid crops are possible in 2 years, though most producers breed once annually in the fall.

Nutrition of Dry, Open, Non-Lactating Females (Maintenance)

  • Input Level: This period demands the lowest feed input; mature females (3-8 years) require enough feed only to maintain body weight from weaning to the last 50 days of gestation.

  • Suitable Feeds: Pastures and crop residue are suitable for maintaining females during this phase.

  • Intake Recommendations: 1.7% of body weight (BW).

Nutrition of Breeding Females

  • Forage-Based Diets: Diets based almost entirely on range and pasture forage, with rare supplementation restricted to periods of peak nutrient requirements, especially during lactation.

  • Protein Supplementation: Common during lactation periods.

Flushing Nutrition for Breeding Females

  • Increase in Lambing/Kidding Rates: Flushing increases rates by 10% to 25% by increasing intake two weeks before breeding, using either protein or energy sources to elevate ovulation rates.

  • Body Condition Scores (BCS): If ewes are at BCS 1-2.5, flushing benefits are evident; at a score of over 3, responsiveness is negligible. Flushing should occur pre-breeding and cease before introducing to rams; return to maintenance diet thereafter.

  • Flushing Options:

    • 0.75 to 1.0 lb of whole corn per day.

    • 1.25 to 1.5 lbs of alfalfa per day.

    • Fresh vegetative pasture.

Nutrition During Gestation

  • Early Gestation (First 100 Days): Feeds should be similar to maintenance feeding, focusing on maintaining health and weight; excess body condition can lead to metabolic issues (ketosis) during the last trimester.

  • Late Gestation (Last 40-50 Days): Critical nutrition period; 70% of fetal growth occurs as well as mammary gland development, where poor nutrition risks weak lambs/kids, decreased milk production, and various health problems. Nutritional requirements for protein and energy increase.

    • Management Recommendations: Separate females based on the number of offspring to enhance energy intake for those carrying multiple fetuses.

Lactation Nutrition

  • Highest Nutrient Demands: Nutritional requirements peak during lactation; females with twins produce 20-40% more milk than those with a single. Production must be prioritized as milk serves as the sole feed for offspring during the first month.

  • Feeding Guidelines: Post-partum, light feeding is advised for the first 1-2 days, ensuring access to plentiful water. By the third day, full feed can be reintroduced, along with a complete mineral mix provided free choice.

  • Sorting by Offspring Type: If feasible, sort ewes and does with single or twin lambs for more tailored feeding.

Creep Feeding for Young Animals

  • Timing for Creep Feeding: Lambs/kids typically show interest in creep feed around 7-10 days of age. Establish a pen in a desirable area with a high palatable 14-16% crude protein (CP) ration using suitable feeds, including: cracked corn, rolled oats, bran, soymeal, molasses, and leafy alfalfa hay.

  • Simple Creep Ration Formulations:

    • 80% cracked corn & 20% soybean meal (SBM)

    • 40% cracked corn & 40% oats/barley & 20% SBM

    • Routine feed freshness helps increase intake.

Weaning Process

  • Pre-Weaning Protocol: Reduce feed, especially grain, for 2-3 days before weaning to prepare ewes and does. During weaning, hold females off feed and water for 12-24 hours to limit the risk of mastitis.

  • Post-Weaning Nutritional Needs: Early weaned lambs/kids require a mix of high energy and high protein (18-20% CP), prioritizing protein from vegetative sources. Target lambs/kids to consume 1-2 lbs/day, reducing protein levels as they grow older.

Feeding Replacement Females

  • Breeding Age: Ewe lambs and goats can be bred at 8 months of age as yearlings.

  • Nutritional Goals: Focus on achieving maximum growth with a high plane of nutrition while ensuring that selected replacement females are not overly fat to prevent fat infiltration into udder tissue, thus hindering milk production.

  • Continued Nutrition Post-Breeding: Sustained nutrition after breeding is critical for the growth of both the female and her fetus.

Nutrition of Breeding Males

  • Ram Maintenance: Rams should remain on a maintenance diet except for 35-40 days before breeding, where they should gain approximately 0.3-0.5 lbs per day.

  • Breeding Condition: Avoid overly fat rams, as they may not exhibit aggressive breeding behaviors.

Mineral and Vitamin Nutrition

  • Influencing Factors: Generally dictated by local forage and soil conditions.

  • Universal Recommendations:

    • Free-choice salt: ~40-50 head consume 1 lb of salt daily.

    • Supplemental phosphorus frequently needed due to low P in forages.

    • Vitamin E supplementation is critical in regions prone to white muscle disease (e.g., western U.S.).

  • Specific Recommendations for Goats: Requirements for trace minerals are largely undefined. Preventative magnesium supplementation in early lactation can address grass tetany issues.

  • Recommendations for Sheep: Limit copper intake to 25 ppm and use sheep-specific mineral products. Administer injectable selenium to ewes in areas where white muscle disease is prevalent, particularly before lambing. Trace mineral supplementation should begin 30 days prior to breeding and continue through weaning.

Potential Nutritional Problems

Pregnancy Toxemia (Ketosis)

  • Description: A common metabolic disease occurring primarily in twin ewes with multiple fetuses near parturition, due to a severe drain of glucose from blood caused by excessive fetal demands.

  • Risk Factors: Ewes that are thin or overly fat, as well as any increasing stress (weather, shearing, handling) elevates risk.

  • Main Causes: A diet deficient in energy during late pregnancy, that reduces rumen capacity; quality feed should be prioritized based on time of year.

    • Signs: Low blood sugar, production of ketone bodies leading to lethargy, teeth grinding, circling, and an acetone smell on breath.

  • Treatment Options:

    • Raise blood sugar levels using IV dextrose.

    • Drench with propylene glycol.

  • Prevention: Focus on proper management and balanced nutrition.

Enterotoxemia

  • Pathogen Information: Caused by Clostridium perfringens Types C & D, organisms flourish in the intestines if feed intake changes suddenly, producing toxins that can be fatal.

  • Mortality: The leading cause of death in lambs.

  • Preventative Measures: Vaccination 30 days before the lambing/kidding, and for lambs at 2-week and weaning stages.

  • Treatment: No specific treatment exists; administer hyperimmune sera and oral antibiotics as necessary.

Acidosis

  • Cause: Sudden changes in feed or energy levels, commonly encountered in feedlot situations or with club lambs/goats, leading to acidic conditions in the rumen which can kill microbes.

  • Treatment Strategies: Drench with antacids and provide electrolytes for recovery.

Urinary Calculi

  • Conditions: Known as water belly or urolithiasis, which can cause urinary tract obstruction, restlessness, and straining to urinate.

  • Mitigation Techniques: Add ammonium chloride to diets at 0.05%, ensure clean water is accessible, and provide appropriate salt and mineral mixtures.

Copper Toxicity

  • Risk Assessment: Typical levels concern 8-11 ppm; sheep are more susceptible (10 times) compared to cattle.

  • Causes: Often results from feeding unsuitable feeds and minerals.

  • Symptoms: Loss of appetite, dark urine, yellowish-brown membranes, leading to hemolytic crises.

  • Treatment Options: Administer sulfate and molybdate as a countermeasure.

Polioencephalomalacia

  • Symptoms: Off-feed behavior, staggering, or paddling; related to thiamine deficiency.

  • Treatment Procedure: Administer IV thiamine hydrochloride to manage symptoms.

Internal Parasites

  • Coccidiosis Characteristics: Occurs under stress in young animals; managed using coccidiostats in feed.

  • Specific Parasite Examples: Haemonchus contortus, also known as the “barber pole worm,” predominantly located in the abomasum.

Summary

  • Unique Ruminants: Sheep and goats display significant nutritional uniqueness compared to other ruminants.

  • Forage Preferences: They have distinct forage selection preferences relative to cattle.

  • Value of Grazing Systems: Multispecies grazing demonstrates notable benefits for resource management and economic diversification.

  • Critical Feeding Practices: Proper management during late gestation and lactation periods is vital for successful sheep and goat production.