Methods of Raising Sheep Review

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Ram

An intact male sheep, also known as a buck. They weigh between 150-400 lbs, reach maturity by 3 years, and hit puberty at 5-7 months of age.

Ewe

A female sheep, regardless of her parity status. They weigh between 120-300 lbs, reach maturity by 3 years, and hit puberty at 6-7 months of age.

Lamb

An immature ram or ewe.

Wether

A castrated male sheep. They typically weigh between 80-170 lbs by 5-8 months of age.

Decreasing daylight breeders

The reproductive classification for sheep, meaning they naturally breed in the Fall and lamb (parturition) in the Spring.

Out-of-season breeding breeds

Breeds capable of breeding out of season to lamb in the Fall. Examples include Dorset, Merino, Rambouillet, Polypay, Dorper, and Katahdin.

147 days (range 140-153)

The average gestation length for a sheep, which runs slightly longer for white-faced breeds.

Finnsheep (Finn Sheep)

A highly prolific sheep breed known for producing litters of 5 to 7 lambs rather than typical singles, twins, or triplets.

5-14 pounds

The typical birth weight range for a lamb.

1 week of age

The timeframe by which lamb tails should be banded (docked).

1 to 4+ weeks of age

The timeframe by which ram lambs are traditionally castrated.

Ethnic market exception

A market dynamic where producers may choose not to dock tails or castrate rams because consumers prefer unaltered animals.

6-10 weeks of age

The standard timeframe to wean lambs, accompanied by a CDT booster vaccine

8-12 years

The average lifespan of a sheep.

US Sheep Population Trend

Began at 7 million head in the early 1800s, peaked at 56 million in 1945 with a wool emphasis, and has dropped to roughly 5.033 million head today with an emphasis on meat production.

1.7 lbs vs. 60 lbs

The stark contrast between annual US per capita consumption of lamb meat vs. beef.

March/April

The peak harvesting months for the lamb industry, strategically timed to coincide with high-demand holidays like Easter, Passover, and Ramadan.

Leg, Loin, Rack, Shoulder

The four primary/primal cuts of a sheep carcass.

Quality Grade factors

Carcass quality evaluation is strictly based on animal age, skeletal conformation, and flank streaking.

Lamb & Yearling Mutton Quality Grades

Prime, Choice, Good, Utility.

Mutton Quality Grades

Choice, Good, Utility, Cull.

Lamb Carcass Indicators

Less than 1 year old, features 2 break joints, round ribs with red edges, and reddish-pink muscle tissue

Yearling Mutton Carcass Indicators

12-24 months old, features 1 break joint and 1 spool joint (or 2 spool joints), and flatter, whiter ribs.

Mutton Carcass Indicators

Over 24 months old, features 2 spool joints, wide/flat/white ribs, and dark red muscle tissue.

Yield Grade

An estimation of the closely trimmed retail cuts a carcass will yield from the primal cuts, scored 1 through 5.

Yield Grade Formula

(10 x Last Rib Backfat) + 0.4.

Four

The number of compartments in a ruminant sheep's stomach system, evolved specifically to ferment and digest forages like grasses and legumes.

Rumen, Reticulum, Omasum, Abomasum

The names of the four stomach compartments in sequential digestive order.

Purchased Energy Feeds

Common grain ingredients added to sheep rations to boost energy, including corn, barley, sorghum, and oats.

Purchased Protein Feeds

Common feed ingredients utilized to meet protein requirements, including soybean meal, dried distillers grains (DDGs), corn gluten feed/meal, brewers grains, and alfalfa meal.

Rumen microbes

The internal organisms responsible for synthesizing water-soluble vitamins (B-complex and Vitamin C) inside the sheep's digestive system.

Water

The single most important and critical nutrient in any livestock or sheep diet.

Grazing

The primary tool used to minimize feed costs in a sheep operation, achieving a 'least cost' management strategy.

Medium wool sheep (Texels especially)

The category and specific breed of sheep that is most highly susceptible to copper poisoning.

Finnsheep

The sheep breed that is genetically most resistant to copper toxicity.

Acute Copper Toxicity

Poisoning that occurs quickly after a sheep accidentally ingests a single large dose of copper.

Chronic Copper Toxicity

Poisoning that builds up over weeks or months due to eating a diet slightly higher in copper than the animal requires.

Liver saturation crisis

The physiological mechanism of sheep copper poisoning: the liver binds copper tightly until it becomes fully saturated, leading to a sudden massive release into the bloodstream (usually triggered by stress), which destroys red blood cells

Jaundice (Yellow eyes/tissues)

A definitive visual clinical symptom of copper poisoning in a live sheep.

Molybdenum and Sulfur

Two minerals that naturally bind to copper in the gut to prevent absorption and accelerate its excretion from tissues.

Ionophores (Rumensin / Bovatec)

Feed additives that actively increase the absorption efficiency of copper, raising the risk of toxicity in sheep.

4 to 8 ppm

The standard safe dietary requirement range of copper for a sheep.

3 ppm Molybdenum

The specific rate of molybdenum supplementation recommended in sheep rations to safely prevent copper toxicity.

Copper Toxicity Prevention Protocols

Never feed swine or poultry feed to sheep; check labels on dairy/beef feeds; test forages for mineral levels; and avoid grazing pastures treated with swine or poultry manure.

Zero

The number of incisor teeth located on a sheep's top jaw (maxilla), which features a hard cartilage dental pad instead.

4 pairs (8 total teeth)

The total number of adolescent milk incisors found on a lamb's lower jaw (mandible).

Medial to lateral (Middle outward)

The sequential physical direction in which a sheep permanent tooth pair replaces a milk tooth pair each year.

1 Year Old

A sheep with 2 permanent central incisors and 6 milk teeth.

2 Years Old

A sheep with 4 permanent incisors and 4 milk teeth.

3 Years Old

A sheep with 6 permanent incisors and 2 milk teeth.

4 Years Old (Full Mouth)

A sheep with all 8 permanent incisors fully erupted.

Undershot (Parrot mouth)

A structural jaw defect where the lower jaw is too short, causing the bottom teeth to sit behind the dental pad.

Overshot (Monkey mouth)

A structural jaw defect where the lower jaw extends too far forward, causing the bottom teeth to protrude past the dental pad.

Resistor / Component

The structural properties of wool.

Keratin

The primary protein block that makes up wool fibers.

Staple length

The total physical length of an uncut wool fleece fiber.

Crimp

The natural structural wave pattern found throughout a wool fiber.

Fiber diameter

The primary structural feature that dictates wool grading, measuring how fine or coarse the individual fibers are.

Top and Sides

The locations on a sheep's body that produce the highest quality, most valuable wool.

Belly and Britch (Leg)

The locations on a sheep's body that yield the lowest quality, poorest grade wool.

Accelerated Lambing

A management strategy where ewes are bred to lamb more than once a year to reduce breeding stock maintenance costs and maximize net financial returns.

3 lamb crops in 2 years

An accelerated lambing schedule where ewes give birth every 8 months (often utilizing a 7-7-10 or 7-8-9 month environmental adjustment model).

5 lamb crops in 3 years (STAR System)

A highly intensive accelerated system relying entirely on natural breeding patterns without utilizing hormones or artificial light control.

Accelerated Lambing Management Requirements

Requires precise knowledge of reproductive physiology, frequent breeding stock replacement, high labor input, and specialized out-of-season genetics.

Barber Pole Worm

The common name for a destructive internal blood-feeding parasite that can quickly cause fatal anemia in pastured sheep.

Refugia

The population of herd parasites that are kept intentionally sensitive to dewormers by leaving a percentage of the flock completely untreated.

FAMACHA

An eyelid color charting system used to selectively identify and treat individual sheep suffering from anemia caused by parasite loads.

Foot Rot

A highly contagious, foul-smelling disease caused by the interaction of anaerobic bacteria (Bacteroides nodosus and Fusobacterium necrophorum) which destroys the tissue of the hoof.

Foot Scald

A painful skin infection confined to the area between a sheep's toes, caused by Fusobacterium necrophorum reacting with Corynebacterium pyogenes during wet weather.

Foot Rot Treatments

Liquamycin (LA-200/LA-300), Zinc Sulfate foot baths, Dry Cow mastitis treatments, and genetic culling selection

CD&T; Vaccine

The essential vaccine protocol given to pregnant ewes 3-4 weeks before lambing, and to lambs at 4-6 weeks of age with a subsequent booster.

Chlamydia Psittaci & Campylobacter fetus

The two primary infectious bacterial pathogens responsible for causing mid-to-late term abortions in sheep flocks.

Pregnancy Toxemia (Ketosis)

A metabolic disorder caused by low blood sugar in overly fat or thin ewes during late pregnancy, caused by inadequate calorie intake while carrying multiple fetuses.

1 lb of corn per head per day

The baseline energy supplement required for a pregnant ewe during the last 6 weeks of gestation to effectively prevent ketosis.

Propylene Glycol

The immediate chemical drench treatment given to an ewe suffering from an active case of pregnancy toxemia.

Sore Mouth (Orf / Contagious Ecthyma)

A highly contagious zoonotic parapoxvirus that causes scabs around the lips and faces of lambs, running its course naturally in 3-4 weeks.

Mastitis

A severe, potentially fatal bacterial infection of the mammary gland (udder) tissue.

Ewe Dry Off Protocol

Abruptly feeding a very poor quality grass hay to ewes immediately at weaning time to halt mammary milk production and prevent mastitis.

Scrapie

A fatal, infectious central nervous system disease belonging to the TSE family, spread primarily from an infected ewe's placenta and birth fluids to lambs.

Codon 171

The specific position on the sheep prion protein gene that has the most powerful impact on determining genetic resistance or susceptibility to Scrapie.

QR

The heterozygous genotype at Codon 171 that renders a sheep intermediately resistant to Scrapie.

QQ

The homozygous genotype at Codon 171 that leaves a sheep highly susceptible to contracting Scrapie if exposed.

RR

The homozygous genotype at Codon 171 that gives a sheep maximum genetic resistance to Scrapie.

Spider Lamb Syndrome (Hereditary Chondrodysplasia)

A genetic abnormality causing deformed bone and cartilage development, inherited as a simple autosomal recessive trait.

Suffolk

The primary meat breed in which Spider Lamb Syndrome originated as a genetic mutation during the late 1960s.

Spider Lamb Clinical Signs

Abnormally long and bent legs, twisted spines, flattened rib cages, and long necks apparent at 2 to 6 weeks of age.

NN

The homozygous dominant genotype denoting a sheep that is completely normal and free of the Spider Lamb genetic mutation.

NS

The heterozygous 'carrier' genotype; the sheep appears visually normal but carries the recessive gene for Spider Lamb Syndrome.

SS

The homozygous recessive genotype that results in a visually deformed 'spider' lamb

Why are lamb prices so high?

Limited number of sheep available now.

How to increase income

Become a niche market

What’s a niche pork market

Duroc and Berkshire

How to market/ marketing strategies of lamb

Seedstock, graded sales, wool pools, value added wool, niche market (organic, all natural, antibiotic free, etc)

What’s the most important thing about lambing?

BE PREPARED!

know signs of labor, have lambing kit ready, caught up on sleep, etc.

Creep feeding corresponds too

Increased performance= increased marketability

Eases load on ewes

Accelerated lambing corresponds to what

Increased net return, reduces maintenance costs of breeding stock per lamb, more uniform supply of lambs throughout the year

Accelerated lambing breeds

Nothing that doesn’t cycle throughout the year (no blacks)

Dorper, Katahdins, Dorset (want twins)

How to get ewes cycling

CiDRs, MGA, controlled lighting, ram effect, GENETICS!

More resources and management needed

How many times do you want to lamb an accelerated ewe?

3 times in 2 yrs

• every eight months

STAR Method

Five lamb crops in three years

Breed 1/23 lamb 5-6/23

Breed 8/23 lamb 1/24

Breed 3-4/24 lamb 8/24

Breed 5-6/25 lamb 1/26