Sheep Flashcards
Ewe breeds
-white-faced
-fine or medium wool, long wool or crosses of these types
-reproductive efficiency (can breed out of season and give birth to twins and triplets)
-wool production
-size
-milking ability
-longevity
“maternal breeds”
Breeds of ewe breeds
-finnsheep
-rambouillet
-merino
Ram breeds
-meat-type breeds
-raised primarily to produce rams that can cross with ewes of the ewe breed category
-growth rate
-carcass characteristics (better AGD and FE)
-“terminal breeds”
-usually black face
Breeds of ram breeds
-Dorper
-Hampshire
-Suffolk
-Southdowns
Dual-purpose breed
-used as either ewe or ram breeds
-have both qualities but don’t excel in either
-usually white face
Breeds of dual-purpose breeds
-Dorset
-Columbia
-Corriedale
How often do wool breeds need to be shorn?
annually
How often do hair breeds shed their coats?
annually
Fine wool sheep
-wool with the smallest fiber diameter
-short in length
-most lanolin
-most valuable (highest quality garments and most versatility)
-least likely to itch
Lanolin
waxy substance
-the more lanolin = the higher quality wool
Fine wool sheep breeds
-merino
-rambouillet
Long wool sheep
-long and coarse wool
-large fiber diameter
-long staple length
Long wool sheep breeds
-Ramney
-Cotswold
-Border leicester
Medium wool sheep
-intermediate between fine and long wool
-most meat-type breeds
Medium wool breeds
-dorset
-suffolk
-southdown
Hair sheep
-do not require shearing
-more heat tolerant
-more hair fibers than wool fibers
-some have parasite resistance
Hair sheep breeds
-katandin
-st. croix
Farm flocks
-10-100 ewes
-purebred or commercial producers
-woven wire or electric fencing for pastures
-good pastures are essential
-open sheds for housing or feeding wintering ewe lambs, pregnant ewes, and rams
-lambing jugs
Where are farm flocks found?
-Great Plains
-Great Lakes
-Midwestern
-New England
-Southeastern states
Lambing jugs
-small 4x5 ft pens
-holding space for ewes and lambs until they are strong enough to go back into the herd
-newborn lambs need an enclosed heated room when the weather is cold
Range flocks
-1,000+ head
-wintered at low elevations where little precipitation occurs
-fed low quality forages in the winter
-brought to wintering area around November 1st
-Rams are turned out with ewes for breeding in December
-pregnant ewes are shorn in April and then moved to the spring-fall range
-lambing occurs on the spring-fall range
-shortly after lambing they are moved to the summer range
-once weaning has happened ewes move back to the spring-fall range
Where are range flocks found?
-the 11 western range states
-in arid and semiarid climates
When are range flocks lambs weaned?
mid-September to October
What breeds can be bred out of season?
-ewe breeds
-dual breeds
When are sheep bred out of season?
breed in spring, lamb in the fall
Short-day breeders
as melatonin levels increase due to decreasing daylight, ewes will exhibit estrus
What season are ewes naturally ready to breed?
fall
Long-breeding season ewes
-heat cycles from mid-to-late summer until midwinter
-Jul - Feb
Intermediate breeding season
-cycling starts in late August or early September until midwinter
ex.)suffolk, hampshire, columbia
Short breeding season ewes
-start cycling early fall and discontinue cycling at the end of the fall
-late Sep. to early Dec.
ex.)cheviot, southdown, shropshire
Less seasonal breeds
-breed almost year-round
-extended breeding season
ex.) dorset, rambouillet, merino, finnsheep, and hair sheep
When do lambs reach puberty?
6-12 months
Average estrous cycle
18 days
Average estrus
30 hours
Signs of estrus
-less pronounced than in other livestock
-often don’t know an ewe is in heat until a ram is present
-seek out the ram and stand to be mounted
What is the most common type of mating?
pasture mating (A.I. is rare in sheep)
Marking harness
harness on the brisket of the ram that marks the ewes when the ram mounts them
-color should be changed every 16-17 days
How many ewes can mature rams breed in a breeding season?
35 ewes
Gestation length
147 days
When should ewes be shorn?
1-4 weeks before lambing
Why shorn ewes before lambing?
-require less space
-barn remains drier
-lambs can nurse easier
-ewes will not expose their lambs to unfavorable weather conditions
Face shearing
removing the wool from around the face
Tagged shearing
remove wool from the rear (dung-wool = wool with fecal material in it)
Crutch shearing
remove wool around udder and teats
What % crop is twins?
200% lamb crop (what is desired)
When will a lamb be up nursing after birth?
within half an hour to an hour
When should docking and castration be performed?
2-5 days after birth and at the same time
What age should lambs be docked by?
2 weeks (but usually within the first 3 days)
Why dock lambs?
-stay cleaner
-less likely to have fly strike
-avoid problems with breeding and lambing
-buyers pay less for long-tail sheep
Where should tails be removed?
end of the caudal folds on the underside of the tail 1 inch from the body
-if docked too short they are more at risk for rectal prolapse
-little bleeding should occur
Emasculator
-crushing and cutting mechanism
-crushes and seals off the blood vessels on the tail
-cuts off the tail right after crushing it
-apply 7% iodine solution to the dock
Emasculatome
-two blunt ends that pinch the tail to reduce bleeding
-knife is used to cut off the long end of the tail inside the burdizzo
-apply 7% iodine solution to the dock
Elastrator
-bloodless method
-rubber ring shuts off circulation to the tail
-causes it to slough off in 1-2 weeks
-fly strike can be a problem so some producers cut off the tail below the band after 2-3 days to speed up the process
Other docking methods
-hot irons
-all in one pliers
-pruning shears
-knife docking - no circulation cut-off so is usually a bloody process
When should castration occur by?
6 weeks old
Knife castration
-bottom 1/3 of the scrotum is cut off with a knife
-pull the testicle until the cord breaks and do this for both testicles
-by letting the spermaticord break it clots itself so no bleeding occurs
Elastrator for castration
-band is placed around the neck of the scrotum just below the teats
-scrotum can be removed below the elastrator band after a few days
Emasculatome for castration
-used on larger, older lambs
-destroys the spermatic cord so that it cannot transport sperm
-testicles will atrophy and shrink in size from reduced blood supply
Why do we castrate?
testosterone taints the meat
Ear tag identification
-most common
-easily removed or caught on something
Tattoo identification
-permanent
-inside the ear or inside the rear flank
-wait to tattoo until lamb is 6 months old
Soremouth
-highly contagious
-causes pustules to erupt around lips and nostrils (eventually form scabs)
-scabs can form on ears, feet, and udders
-scabs fall off after 1-4 weeks
-causes pustules anywhere without wool
-not fatal but decreases production
-can vaccinate
How is soremouth spread?
-nursing lambs can spread to the teats and udders of their dams (possibly causing mastitis to develop)
-spread via infected fomites and other sheep
-is zoonotic (orf in humans)
-can survive for years outside the sheep
Urinary calculi
-metabolic disease of male sheep
-occurs when calculi (made up of phosphate salts) lodge in the urinary tract and prevent urination
-mainly in males being fed high grain, low roughage diets
-diet is improperly balanced for calcium and phosphorus
-lack of water
Urinary calculi symptoms
-urine dribbling
-humped-up appearance
-kicking at the belly
-straining to urinate
Urinary calculi treatment
-add ammonium chloride to diets at a 0.5% level to help acidify urine and prevent calculi formation
-can do surgery (clip the tip of the urethra off)
-will euthanize eventually
Footrot
-caused by the interaction of Bacteroides nodosus (survive in the hoof for extended periods) and Fusobacterium Necrophorum (normally found in soil and manure)
-most prevalent and highly contagious in wet, moist areas
-causes production losses, treatment and prevention costs, premature culling, and reduced sale value
-very contagious
Footrot symptoms
-lameness
-reduced weight gain
-decreased milk and wool production
-decreased reproductive capabilities
-lying down for extended periods of time (rubbing off wool/hair on their flanks, brisket, and knees)
Footrot prevention
-properly shaping hoof
-trimming hooves at least twice a year (before breeding and in the spring when shearing)
-trim hooves more frequently in wet environments
-vaccine (60-80% success rate)
-foot bath (10% zinc sulfate solution or copper sulfate)
Lamb teeth
-8 temporary incisors that erupt ~2 months old and remain until 12 months old
-usually born without teeth
Yearling teeth
~12 months of age
-two center larger wider permanent teeth
-6 temporary incisors (3 on either side)
2 year old teeth
-second pair of permanent incisors comes in
-4 temporary incisors (2 on either side)
-4 permanent incisors
3 year old teeth
-third pair of permanent incisors comes in
-2 temporary incisors (1 on either side)
-6 permanent incisors
4 year old teeth
-all 8 permanent incisors
-full mouth
Beyond 4 year old teeth
-teeth appear longer due to receding gums
-greater space between teeth
-exact age cannot be determined
