Sheep and Goat Production Final
What are the aspects of the ram effect?
-cheap synchronization tool -introduction of rams, previously isolated, to ewes -stimulation of estrus -leads to an increase on LH -results in most anovulatory females cycling and ovulating with about 48-50 hrs -flehmen response
What should be done when introducing new animals into the flock?
-check animals before purchasing -4 weeks separation from flock -observe, deworm, trim feet -visual inspection before purchase
What are the physiological breeding programs with ewes?
-hormone imbalance -cystic ovaries-luteal cysts or follicular cyst -infections -early embryonic death
What are the benefits to a BSE?
-identify bad rams -reduce the number of rams needed -prevent wasted breeding season
What is the purpose of a necropsy?
-identify disease -find right treatments -limit losses -improve knowledge of disease effects -health maintenance program brainstorms
Saanen
-originated from Switzerland -one of the most popular breeds of dairy goats in the U.S. -Medium to large in size and have distinctive erect ears and a straight or dished face -white is preferred, spots in the skin and in the hair are allowed -noted for volume of milk production
Toggenburg
-originated from Switzerland -one of the oldest known dairy goat breeds -medium in size, generally seen with tassels -light brown to grey in color with white Swizz markings on the face, lower legs and tail area -highly productive dairy breed
Dorset Sheep
-originated in England -Horned and polled -Medium sized, white-faced, produces a light shearing, open fleece -Mature early both sexually and compositionally -known for breeding out of season and prolificacy and milking ability -extremely heavy muscled -good mothering instinct
Southdown
-originated in England -one of the oldest sheep breeds still in existence -imported into U.S. in 1803 -farm flock breed -common in show industry -medium to small in size with light brown face an dlegs -used to produce meaty, light weight carcasses -low maintenance breed -average prolificacy and milk production
Disadvantages of A.I.?
-supplies to synch estrus -special procedures -trained personnel required -availability of semen
What do we examine females during mid-gestation?
-teeth -feet -udder -FAMACHA -general health -wool quality
What is the treatment and prevention of Chlamydiosis?
-vaccines available -use antibiotics in an outbreak -tetracyclines -interrupt infective cycle -remove aborting ewe from flock until discharge cleared -dispose of fetus and membranes -clean facility -can cause human abortions
When can pregnancy be determined and when does it become challenging?
35-40 days after; 90 days
Cause enzootic abortion in ewes. The cause is chlamydia psittaci (gram negative bacteria) and older ewes are usually immune if flock has had it before. Organism is excreted from aborted fetus, membranes and fluids for 3 weeks. Insertion from ingestion. Diagnose it from flock history, lab workup and paired serum samples. Abortions happen around 60-90 days after infected or from gestation and can have weak, unthrifty lambs.
Chlamydiosis
What are the common diseases in ewes?
Chlamydiosis, Vibrio Campylobacteriosis, Toxoplasmosis, Salmonellosis, Ketosis, Milk Fever, Ring Womb
Sire breeds used primarily as terminal sires because of growth and carcass traits
Dorper (hair sheep), Hampshire, Southdown, Suffolk and Texel
Medium wool breeds
Dorset, Finnsheep, Gulf Coast Native, Hampshire, Polypay, Southdown, Suffolk and Texel
A glycoprotein that comes from the anterior pituitary and targets the testis (leydig cells) and the ovaries (thecal cells and luteal cells). Its function is to stimulate testosterone production, stimulate ovulation, and induce formation of the CL as well as progesterone secretions
Lutenizing hormone (LH)
also called a post-mortem exam, is an examination of an animal after death. Performed to obtain an accurate cause of death and when done properly, involves looking at the animal as a whole as well as looking at each individual organ within the body.
Necropsy
Type of A.I. that includes skill needed, equipment costs higher (scope, light, cradle), have to hold ewes off feed and water for 12 hrs, considered a type of surgery and semen is deposited in the uterine horn. Used in sheep
Laprascopic
Comes from the Testis (leydig cells) and follicles (thecal cells). Target sthe seritoli cells, accessory sex glands, brain and skeletal muscle and follicles (granulosa cells). Functions in spermatogenesis, acessory sex glands' secretions, secondary sex characteristics and substrate for estradiol synthesis
Testosterone
How much goat meat is eaten by the average U.S. citizen in 1 yr?
less than 1lb
What do temp and humidity mainly effect?
fertility, embryo survival and fetal development
What do goats produce that is more pricey than wool?
mohair
Tube like instrument that spans vulva and posterior vagina allowing visual inspection of the cervix
speculum
Polypay
-Developed in California -Synthetic breed developed at the U.S. Experiment Station in Dubois, Idaho -Reciprocal crosses of (DorsetxTarghee) x (FinnsheepxRabouillet) were used in the development -suited to confinement rearing of sheep -very productive but require intensive management
Finewool breeds
-Booroola Merino -Debouillet (RambouilletxDelaine) -Merino -Rambouillet
Finnsheep
-Originally from Finland -Require intensive management -mood known for extremely high prolificacy (mature ewes produce 3+ lambs) -milking ability and easy lambing with maternal instincts -very poor fleeces and are slow growing and light muscled -sheep dairies
Hampshire
-Originated in England -popular sire breed -common to show industry -genetics have been infused with Suffolk genes in the past 20 yrs -dark brown to black legs, face and ears -white body -wool cap on head (extends over the poll to typically between the eyes) Known for rapid growth and muscularity
Texel
-Originated in the Isle of Texel off the coast of the Netherlands -became available to U.S. sheep producers in 1990 when released from quarantine to U.S. Meat Animal Research Center in Clay Center, Nebraska, where thy were evaluated for their potential in crossbred lamb production -Great muscle development and leanness -Texel sired lambs one full leg score advantage in breed comparisons and less total carcass fat (seam fat) -fast growing -heavy muscled -natural parasite resistance -dystocia problems -out of season breeders
What doe we test in a BSE?
-Semen mophology -Semen motility -testicle size and development -libido -the stud or dud phenomenon
Katahdin
-an improved breed of hair sheep -first hair breed to meet North American industry standards for carcass quality -cross between British meat breeds, the suffolk, african hair sheep, the st. croix and later the wiltshire horn -easy-care, low-maintenance, meat-type sheep that is naturally tolerant of climatic extremes and capable of high performance in a variety of environments -natural resistance to internal parasites -one of the most popular breeds of registered sheep in the U.S.
What are the signs that a sheep may be diseased?
-behavior -appearance -attitude -appetite -temp
Why do we pregnancy test?
-cull open females to save on feed costs -determine those that conceived but did not gestate full term improve lambing management
Columbia
-developed at the U.S. Sheep Experiment Station in dubois, Idaho -based on a crossbred foundation of Lincoln rams and Rambouillet ewes -Largest of the crossbred breeds -best suited to the better range areas of the West -extremely hardy -produce 10-16 lbs of 3/8 blood wool (coarser than rambouillet)- long, crimped wool -ewes a relatively prolific and productive -labs faster growing than rambouillet and merino -white faced/ no black fibers -polled
Targhee
-developed in the U.S. at the Dubois Experiment Station in Idaho -Foundation developed by breeding outstanding Rabouillet rams to ewes Corriedale x Lincoln-Rambouillet breeding -developed under range conditions -selection based on production performance -moderately prolific and reasonably good milking -white faced and polled -intermediate in size -fleeces mid-way between that of a rambouillet and columbia in fineness (1/2) blood fleeces -great flocking ability -breed has embraced flock EPD and data
Barbado
-extreme hardiness -reproductive effieciency -out of season breeding -rams get a premium in ethnic markets (natural look) -one of the most prolific sheep breeds in the world -parasite tolerance
What do you watch for when introducing new animals into a flock?
-foot rot -brucella ovis -caseous lymphadentitis -parasites-fecal egg count
What are the advantages of A.I.?
-genetic improvement through increased use of superior sires -disease control -extend the life of the male -more females bred to single sires
What does synchronization of estrus do?
-gives the oppurtunity to shorten lambing season, while still catering to a reasonable male to female ratio
What were the 5 goals in developing the Polypay breed?
-high lifetime prolificacy -good lamb crop at 1 yr of age -ability to lamb more frequently than once/yr -good growth rate of lambs and wool -good carcass quality
Why do we count fetuses?
-improve nutritional management -decrease lambing labor -expected number of lambs born -keep more fertile genetics
What are anatomically breeding problems in ewes?
-infantile organs -incomplete repro tract -mechanical injury-tear; prolapse -obstructions
Method of using a CIDR
-insert for 11-12 days -stagger removal -use vasectomized ram -breed on the first natural heat -skip the first silent heat to increase conception and stagger conception time more
What are causes of a biosecurity risk?
-introduction of new sheep into a flock -no vaccinations -feeding in unsanitary conditions -storage of feed -feeding bad feed
Why do we determine stage of pregnancy?
-lambing window to know within 2 weeks of when female will give birth and know who the sire is
Selection of breeds should be done with what in mind?
-location -production goal -current production
What are the marker aids of estrus detection?
-marking harness -grease and chalk -heat-mount detectors
What are the factors affecting ram performance?
-optimum libido during short days -testicle size increased-sperm production, quality -nutrition and health -temperature -keep ram lambs separate from mature rams
Nubian
-originated from Africa -most popular breed of registered dairy goat in the U.S. -noted for higher butterfat than other dairy breeds and their distinctive long, drooping ears and "Roman nose" -any color accepted -"Jersey of milk goats"
Nigerian Dwarf
-originated from Africa -popular breed of dairy goats in the U.S. for small farms -miniature goat with confirmation similar to that of larger dairy goat breeds, with erect ears -main color is black or chocolate, random white markings and spots are common -found in petting zoos
South African Boer Goat
-originated from South Africa -hardy, fast growing meat-type goat -medium size with prominent horns and broad drooping ears -brown head and neck with white body and legs, having short to medium hair -good meat-type confirmation with superior spring of ribs, body length and muscling -very docile -show industry -has changed the goat industry
Suffolk
-originated in England -very old sire breed used in commercial production -one of the oldest breeds -first reported case of scrapie -recessive spider gene common as well (Walking Tall) -largest breed of sheep in the world -common to show industry -free of wool on head, with black head, legs and bell-shaped ears -body usually white but may have blue tint -alert, active sheep -grow very fast and produce lean, muscular carcasses -ewes are very prolific and heavy milking but produce poor fleeces
Rambouillet
-originated in France -Descended from Spain Merino -King Louis purchased from Spain -Rambouillet developed in Rambouillet, France -Originally dual purpose for their excellent fine-wool fleeces and acceptable growth and carcass traits -dominant range ewe in Western U.S. and TX -#1 Sheep of TX -Larger and faster growing than Merino -White-faced -selection in recent years towards larger, more open faced -wool blindness
Dorper
-originated in South Africa -Developed in 1930's from the Dorset Horn rams on a Blackheaded Persian ewe -Developed for arid extensive regions of S. Africa -Produces a mixture of hair and wool and will naturally drop the wool/hair if not shorn -very fertile -breeds out of season -1 lamb/crop, maybe 2 -lambing interval: 8mo, lambing 3x in 2 yrs -adaptable, hardy, reproduction rates and growth and mothering ability -lambs grow rapidly and have high weaning weights -white body -head may be black (dorper) or white (white dorper) -85% registered have black head -2nd most populous breed of sheep in South Africa -Superior leather
Merino
-originated in Spain -most dominant breed in the world wide sheep industry -most have very fine fleeces, some strains of breeds in australia are coarser -#1 Wool Producers World Wide -smaller in size -slow growing -very hardy, long living sheep -excellent flocking instinct -white faced -excessive rolls of skin -Screwworms inf flesh
Spanish goat
-originated in spain -goats of mixed breed origins -native to TX for brush control -"meat goat" kept largely for meat production -high variability in appearance and performance as little planned selection has occurred -both males and females are horned -colors range from solid black, brown and white to fawn and white with many color combos of spotting -very prolific and hardy -utilize a great deal of browse, thus used to clear brush and clean up re-growth in cleared areas
St. Croix
-originated in the Virgin Islands- "Virginia Island White" -very heat tolerant -both sexes are polled and rams have a large throat ruff -exceptional parasite resistance
Angora
-originates from Turkey -sheared 2x a year -managed primarily under range conditions. Utilize a lot of browse -Over 90% of the U.S.' Angoras in TX, mostly in Edward's Plateau -The finest hair (most valuable) is produced by goat kids with the hair getting coarser as the goat gets older -They grow 1" of hair/mo -biggest problem is maintaining pregnancy due to cold shock and stress when sheared
Gulf Coast Native
-spanish sheep first arrived in the 1500s -resistance to internal parasites (barber pole worm) -Florida Agriculture Experiment Station in Gainsville has a flock which has been maintained w/out the use of anthelmintics since 1962
What are ways to maintain a healthy flock?
-vaccinate -deworm, cull and ID -monitor diseases -necropsy
What does a successful A.I. require?
-timing -good semen -reducing stress -identifying estrus (active) females -good record keeping
What is bagging?
-udder palpating -most widely used, fairly accurate, time when correct and no sorting on type of pregnancy or how far along
What are pregnancy testing methods?
-ultrasound -bagging -blood tests -marking harness
3 classes of sheep breeds
-wool breeds -meat breeds -dual purpose breeds
when do we do a BSE?
60 days before planning to breed (time for spermatogenesis)
goats breeds
Angora, Boer, Nubian, Saanan, Spanish, Toggenburg
provides a slow-release administration of progesterone which artificially extends the luteal phase.
CIDR
Hair Breeds
Barbado, Dorper, Katahdin, St. Croix
Biggest problem in medium wool breeds is___
Colored fibers
Dual Purpose Breeds
Columbia, Dorset (hot house lambs) and Polypay
Crossbred wool breeds
Columbia, Targhee
Comes from the testis (sertoli cells) and follicles (granulosa cells) and targets the hypothalamus and pituitary as well as the entire repro tract and brain. It functions to elevate secretory activity, regulate GnRH release and Sexual behavior (heat)
Estradiol
Estrous cycle for a ewe and doe, estrus Gestation and breeders
Ewe:17 days Doe:21 days 24-36 hrs 148 days short day breeders
Increasing the level of nutrition (energy/protein) about 14-20 days before breeding. This increases the ovulation rate by 30%
Flushing, can also do this by deworming and a new pasture
A glycoprotein that comes from the anterior pituitary and targets the testis (seritoli cells) and the ovaries. It functions in spermatogenesis, follicular development, sertoli cell function and estradiol synthesis
Follicular Stimulating hormone (FSH)
Is a decapeptide and is produced by the hypothalamus and anterior pituitary to stimulate the release of LH and FSH
GnRH
What are the 2 most popular sire breeds in commercial sheep production?
Hamps and Suffolks
Which cultures consume the most goat meat?
Hispanic, Muslim, and Carribean
Selection for two or more traits simultaneously. Minimum standard set for each trait and culled if don't meet one of the traits (Body size + wool)
Independent culling levels
removal of excess skin (Merino)
Mulesing
A steroid that comes from the CL and placenta and targets the endometrium and myometrium, hypothalamus and mammary glands. Its function is to maintain pregnancy, inhibit GnRH release and mammary growth and secretion. CIDRs utilize this to synchronize estrus
Progesterone
Maternal breeds
Rambouillet, merino, booroola merino (f gene), corriedale, debouillet, delaine, finnsheep, romanov and targhee
#1 influence on profit margin. Takes a combo of age at sexual maturity, ability of ewe to conceive, ovulation rate, ease of lambing, embryonic and postnatal losses, mothering ability, ram fertility and if bred on 1st cycle
Reproductive efficiency
periods of estrous cycles occuring only during certain seasons of the year (sheep, goats, deer, mare)
Seasonal polyestrus
Addresses multiple traits by focusing on one at a time until satisfied. Works if traits are correlated and can backfire
Tandem selection
The type of A.I. that is easy, cheap, requires some skill and equipment needed (gun, speculum and light source) and the semen is deposited in the cervix or uterus. This is used in goats and deer.
Trans-cervical
Type of A.I. that is cheap, easy, low conception results and semen is deposited into the vagina
Vaginal
What are the selection traits
adaptability, reproductive efficiency, rate and composition of lamb growth, and wool production
What is the first step of a necropsy?
carefully inspect the animal, look for any signs of trauma and not any other obvious abnormalities (lesions)
What are the methods of synchronizing estrus?
controlled internal drug release (CIDR) and the ram effect
3 different types of selection
individual selection (ram test), Pedigree selection (ancestors), and progeny test (offspring)
Factors to adaptability
longevity, hardiness, climate conditions, feed and environment
condition when females do not exhibit regular cycles
periods of anestrus
What regulates seasonality?
photoperiod-periods of light and temp. The pineal gland produces melatonin which stimulates the release of GnRH from the hypothalamus. Melatonin secreted at night
What is #1 in wool production for selection traits?
pounds of clean wool shorn per ewe
What are the pros and cons of ultrasounding?
pros: accurate, early and single or twins cons: cost, skill, timing and labor
What is emphasized in sire breeds?
rate and composition of lamb growth
What are normal males during a BSE?
semen production is 20 million/gram/day and will ejaculate 0.5-1.5 mL
When is embryo fertility most critical?
the first 25-30 days
