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Flashcards in Sheep and Swine Exam Deck (108):

What are the merits of sheep production​?

  1. Enterprise competitive
  2. Dual purpose (lamb and wool)
    1. increasing demand for lamb
  3. Multiple Birth Potential
  4. Landscape and Forage Utilization/Optimization
    1. Synergy with Wyoming's landscapes


Enterprise Competitive

Variable costs/ewe

  • WY- $92
  • TX- $118
  • ND- $127
  • KY- $140
  • US Ave.- $110


Estimated Returns 

cattle vs. sheep

  • Average for:
    • Cattle $184
    • Sheep $37.40
    • Sheep AUM adjusted $187


--Increasing Demands--

Food Service


Regional Growth

  • +13% Food service
  • +7.0% Retail
  • Regional Growth
    • CA +13%
    • TX +13%
    • Southeast +16%
  • Millenial Growth


--Wool Economics--

What are the factors that play in the net revenue/ewe?

  • (+) gross wool revenue/ewe
  • (-) shearing cost
  • (-) wool labor ($0.05/lb)
  • (-) warehouse fee ($0.15/lb; core, freight)


Multiple Birth Potential


252 lbs of lamb weaned per ewe or 168% of the ewes body weight


How do sheep maximize grazing resources?

Sheep eat more forbs and shrubs than cattle do, and consume less grass. 

They also tend to graze upland, while cattle prefer bottoms. 

  • Cattle- 
    • grass 74%
    • forb 12%
    • shrub 14%
  • Sheep
    • grass 42%
    • forb 38%
    • shrub 20%


How MUCH do sheep maximize grazing resources?

52% increase in grazing days when sheep followed cattle in grazing system.

For every cow-calf pair you can add a ewe without decreasing the stocking rate


Sheep can be used to manage _____________?

Invasive species


Using sheep to manage invasive species as a business is termed what? 

Targeted grazing business

  • can use a temporary electro-net fence
  • cash flow
    • 1100 yearling ewes
    • $0.16/day--> producers pay
    • $5.00/head month--> landowners pay


Cattle/Buffalo population vs. Sheep/Goat population

  • larger sheep/goat population in Africa, Asia, Europe, Oceania, and The World overall
  • America's have a larger cattle/buffalo population


Top Sheep producing states 2017

-All Sheep and Lambs-

  1. Texas (700,0000
  2. California (585,000)
  3. Colorado (395,000)
  4. Wyoming (360,000)
  5. Utah (285,000)
  6. Idaho
  7. South Dakota
  8. Montana
  9. Iowa
  10. Oregan


Top sheep producing states 2017

-breeding sheep-

  1. Texas (435,000)
  2. California (270,000)
  3. Wyoming (225,000)
  4. Utah (205,000)
  5. Colorado (160,000)
  6. Montana (159,000)
  7. South Dakota (155,00)
  8. Idaho (138,000)
  9. Oregon (101,000)
  10. Iowa (95,000)


Wyoming Sheep Industry Stats

  • Sheep inventory (rank)
  • Breeding sheep (rank)
  • Wool production (rank)
  • Wool Value $/lb (rank)
  • Sheep operations (#)
    • 1-99 hd%
    • 100-299 hd%
    • 300-999 hd%
    • 1000-10,000 hd%

  • Sheep inventory (rank) --> 360,000 (4th)
  • Breeding sheep (rank) --> 275,000 (3rd)
  • Wool production (rank) --> 2,300,000 (2nd)
  • Wool Value $/lb (rank) --> $1.80 (2nd)
  • Sheep operations (#) --> 771
    • 1-99 hd% --> 72%
    • 100-299 hd% --> 10%
    • 300-999 hd% --> 7.5%
    • 1000-10,000 hd% --> 9.4%


Sheep population in the U.S from 1970-2015



1945: 54 million sheep in US

2016: 5.2 million sheep in US


Consumption, Production, Imports

Consumption has decreased, minor increase

Production has decreased

Imports are increasing


Imports and production mirrors consumption


increasing damand

Food service


regional growth

millenial growth

  • +13% food service
  • +7.0% retail
  • regional growth
    • CA +13%
    • TX +13%
    • Southeast +16%
  • Millenial growth



Per capita lamb consumption

  • an imperfect estimate
  • per capita consumption= (cold storage inventory + imports) - (year end stocks +exports) / US population= about .5-1 lb
  • so whats the problem? 
    • ​immigrants


Ethnic markets

Ethnic markets have a higher demand for lamb.

  • pay more for the same lamb in Pennsylvania than in South Dakota
  • price in cull ewes has risen, destined for ethnic market


Commodity vs. Ethnic

     Commodity                        Ethnic______________

65-85lb carcass                      40-55lb carcasses

grain finished                           grass finished

castrated wethers                    intact males

predetermined price                bartering and negotiation

federally inspected                   halal slaughter

wool breeds                               variety of breeds including hair                                                              sheep


How do producers in states far removed from ethnic populations tap into ethnic market channels?

  • Direct Marketing
  • Commodity Marketing


Direct Marketing

Direct Marketing

  • all facets of production tied into one
    • lambing, finishing, marketing, distribution
  • price premium received due to proximity to specific consumers
  • Quality control feedback more efficient
  • lack of economy on scale can be costly
  • scarcity of USDA slaughter facilities


Commodity Marketing


  • large production systems
  • feedlot finished lambs
  • lambs harvested through traditional USDA inspection channels
  • Traditional Dristribution, Food Service, and Grocers


3 Major Processors

  1. Superior Farms, Dixon, CA
  2. Superior Farms Denver, CO
  3. Mountain State Rosen, Greeley, CO


Overview of Sheep Enterprise Revenue

  • lamb production represents majority of revenue on any commercial sheep interprise
    • 88-94% of revenue comes from lamb production
      • revenue from lamb sales occurs in late summer-fall 
    • 6-12% of revenue comes from wool
      • timing of revenue flow from wool will be spring to early summer


Commercial Sheep Production Systems


  • extensive systems
    • eg. Western Sheep
  • Intensive systems
    • eg. midwest/farm flock


Commercial Sheep Production Systems


  • club lamb/show flocks
  • dairy sheep
  • hand-spinning flocks
  • seedstock/stud ram
  • lamb feeding industry
    • commercial lamb feeding
    • farm flock feeding


Extensive Production

  • range sheep
  • forage based grazing operations-rangelands
  • generally wool breeds
  • economy of scale, larger flocks >500 hd flocks
  • one lamb season per yr <150% lamb crop
  • lambs weaned later than 120 days
  • generally utilize commodity based marketing
    • Mtn. States Rosen, Superior Farms


Intensive Production

  • high plain, farmed feeds
  • accelerated lambing (3 lamb crops in 2 yrs)
  • 150-250% lamb crop
  • large and med sized flocks
  • lambs weaned at 60-90 days
  • finishing operation
  • utilize commodity and direct marketing


Sheep Breeds Classification

  1. Production Type (meat, wool, dual-purpose)
  2. Maternal and Growth (dam breeds, sire breeds)
  3. Wool breed types (fine, med, course, hair)
  4. Geographic origin (british breeds, tropical)

ALL sheep are produced for meat consumption regardless of breed-type classification


Sire Breeds

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  1. Suffolk
  2. Hampshire
  3. Texel


Fine Wool Breeds

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  1. Maerino (AU, NZ)
  2. Rambouillet
  3. Cormo
  4. Targhee?


Medium Wool/Dual Purpose Sheep

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  1. Targhee (USA)
  2. Columbia (USA)
  3. Dorset
  4. Polypay (USA, prolific)
  5. Corriedale
  6. South African Meat Merino


Hair Sheep

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  1. Dorper
  2. Katahdin
  3. Saint Croix
  4. Royal White
  5. Barbados Blackbelly


Why crossbreed?

  1. To optimize gene frequencies
    1. mix strengths of different breeds to create something that is needed but may not currently exit
    2. allows focus on Maternal traits in the ewe flock and growth and carcass value in the sires
  2. To utilize heterosis
    1. important, positive effects on performance in both the corssbred lamb and the crossbred ewe


Heterosis in Crossbred LAMBS

  • BW- 3.2%
  • WW- 5.0%
  • Postweaning DG- 6.6%
  • YW- 5.2%
  • Conception Rate- 2.6%
  • Prolificacy of Dam- 2.8%
  • Survival, Birth- Weaning- 9.8%
  • Carcass Traits- ~0
  • Lambs born per ewe exposed- 5.3%
  • Lambs weaned/ewe exposed- 15.2%
  • Weight of lamb weaned/ewe exposed- 17.8%


Production of Pure and Crossbred lambs

                   N            Survival         Ave.                  Lb. of lamb weaned/ewe

                                    rate at           WW                      lambing


Purebred      998        80                     73                          58

Crossbred    285         92                     75                         69


Exhibition Quality

  • the appearance of a sheep at a show or sale is not a good guide to its genetic potetential for production
  • most sheep breeders are distracted to some degree from selection for appearances
  • very few breeders of purebred sheep can afford to ignore the appearance of sheep and select soley on performance and gentic potential


Selection Goals for a Seed Stock Producer

  • produce terminal sires for range sheep operations
    • emphasize selection for growth rate and carcass quality
    • emphasize selection for lamb hardiness/survival
  • Produce fine-wool rams and replacement ewes for use on desert range
    • emphasize fleece characteristics and adaptation to environment


Selection Goals for Commercial Operator

  • maximize income from lamb and wool in a farm flock situation. Area has a good wool market
    • emphasize prolificacy, growth rate, maternal ability, and acceptable fleece quality
    • What would you do if this area did not have a good wool market?
  • Produce crossbred replacement ewes for use in mid-west and eastern farm flocks
    • emphasize prolificacy, milk production, survivability, and growth rate


WY Ram Test Certified Rambouillet Index

60 (ADG) + 4.0 (365 adj staple length) + 4.0 (364Clean Wool) + (Fiber Diameter Points)

  • (22-actual micron) x 3; (max of +9 points)
  • (actual micron-22)x 3; (max of-6points)
  • (22.0–actual CV) x 1.25; (max of±5)







  1. class Mammalia (milk giving)
  2. order Artiodactyla (even toed, hoofed animals)
  3. family Suida (consists of sixteen species of pigs and hogs. Members of the Suida originally occurred across Eurasia)
  4. genus Sus


Modern Production pigs are derived from predominantly two species:

  1. Sus scrofa- wild hog from continental Europe, from which most domestic breeds are derived
    1. course hair, large legs and feet, a long head of tusks, a narrow body and great ability to run and fight
  2. Sus vittatus- the race of the East Indian swine that also contribute to today's domestic swine
    1. smaller, more refined than the European wild hog. Black with white streak along the side, a scavenger used to eliminate human food waste


European Wild Swine

  • very aggressive
  • poor eyesight, but keen sense of smell and hearing
  • average 2 yr old weighs 325-350#
  • low prolificacy
  • babies are striped


Swine History

  • Columbus is credited for introducing swine to the New World 1493
  • First good quality hogs came to US in 1609 at Jamestown
  • Settlers moved westward and spread hogs which eventually became concentrated in the Corn Belt
  • In the 1990's swine spread to the southeast and are now spreading to the southwestern US


Top Swine Producing States

  1. North Carolina
  2. Minnesota
  3. Illinois
  4. Indiana

Produce 68.8% of hogs

Iowa leads the nation with 31% of all hogs on inventory


US Hog and Pig Inventory by State

  1. Iowa 31.4%
  2. North Carolina 13%
  3. Minnesota 12%
  4. Illinois 6.9%
  5. Indiana 5.5%
  6. Nebraska 4.7%
  7. Missouri 4.2%
  8. Ohio 3.3%
  9. Oklahoma 3.1%
  10. Kansas 2.7%


Trends in Herd Size of US Pig Producers

  • Herd Size and % Market Share
  • 1000-- 4%
  • 1001-1999--8%
  • 2000-4999--25%
  • 5000+--63%


Commercial Swine Production

  • Ave. pigs/ litter
  • US. pig and hog inventory
  • Breeding inventory
  • Market Hog inventory

  • Average pigs saved per litter=10.58
  • Total hogs and pigs in the US= 70.9 million
  • Breeding Inventory= 6.0 million
  • Market Hog Inventory= 64.8 million


Demand has moved from a _______ type hog to the present ____________ type hog. 

  • Demand has moved from a lard-type hog (carcass high in fat) to the present lean-meat-type hog (carcass high in meat compared to lard).
  • The hog carcass has one of the highest dressing precentage of any livestock species (70-75% in swine vs. only 60-65% in cattle)


Maternal Breeds of Pigs

  1. Chester White
  2. American Landrace
  3. Yorkshire
  4. Large White


Sire Breeds of Pigs

  1. Berkshire
  2. Hampshire
  3. Poland China
  4. Spot
  5. Hereford
  6. Tamworth
  7. Pietrain
  8. Duroc


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Chester White (maternal)

  • originated in Chester County, PA 1848
  • White with drooped ears
  • large litters
  • gentle disposition
  • good mothering ability
  • lean carcass and large hams


Reproductive Parameters

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Landrace (maternal)

  • originate in Denmark- not imported into US until 1940's
  • American landrace is 1/16-1/64 poland China
  • White hog with drooped ears
  • long belly
  • 16-17 pairs of ribs (extra vertebrae)
  • high meat quality- known for bacon


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Yorkshire (maternal)

  • orinated from England "Large White Descendent"
  • "The mother breed"
  • white with dished face and erect ears
  • lean, good carcass quality
  • Maternal Breed


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Large White (maternal)

  • originated in England
  • Erect ears
  • white color, pink skins, dished face
  • long deep sides
  • good bacon production
  • maternal breed


Carcass Parameters

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Berkshire (sire breed)

  • originated in Berkshire, England
  • black with white face
  • erect ears
  • dished face
  • known for quality carcass characteristics
  • American Berkshire association- first swine registry in the world 1875


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Hampshire (sire breed)

  • originated in Boone County, Kentucky
  • Black with white belt
  • erect ears
  • known for meat quality
  • low backfat
  • used as a boar in a terminal cross breeding scheme



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Poland China (sire breed)

  • originated in Miami Valley, Ohio
  • black with white face, feet, and tip of tail
  • great soundness in feet and legs
  • very efficient at feed conversion-- fast growers
  • although they have larger litters, mothering ability is low (lots of crushed pigs)


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Spot (sire breed)

  • originated from the Poland China Breed (aka Spotted Polland China)
  • meat breed
  • high carcass value
  • great rate of gain


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Hereford (sire breed)

  • oringinated La Platta, MO
  • mix of poland china and duroc
  • white face, red body, and at least 2 white feet and white underline
  • erect
  • well-finished carcass and heavy shoulders


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Tamworth (sire breed)

  • originated in England
  • Very lean meat
  • known for bacon
  • good carcass value
  • long bodied
  • long straight snout
  • long legs-- can graze rough country


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Pietrain (sire breed)

  • originated in Pietrain, Belgium
  • medium size, white with black spots
  • erect ears
  • extreme in muscle development
  • PSS carrier
  • used as a terminal sire for show pigs


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Duroc (Duroc Jerseys) (sire breeds)

  • originated in Eastern US (New Jersey and New York)
  • blend of Jersey Reds and Durocs of New York
  • colors can vary from golden to deep red
  • droopy ears
  • good carcass quality
  • known for rate of gain
  • used as boar in terminal cross breeding schemes


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Chinese Meishan 

  • originated in Mainland China
  • Excellent mothering ability
  • known for exceptionally large litters (up to 30 piglets have been documented)
  • poor carcass quality


Selection Systems

Three systems for selection were designed the result in maximum progress

  1. Tandem Selection
  2. Independent Culling Level
  3. Selection Index- Preferred


Tandem Selection

  • breeders select on one trait at a time until maximum progress has been achieved, then they select another trait for improvement. Progress is based on the heritability of the trait under selection
  • Drawback- selection of one trait may not always result in improvement of another, and may even be antagonistic
  • example: leanness and reproduction


Independent Culling Level

  • Minimum standards are set for several traits. The failure to meet these standards result in slaughter or removal from the herd. Because of the large litters produced, standards can be kept high resulting in rapid progress (Envy of cattle breeders!!)


Selection Index

  • By using selectionindex, all important traits can be easily combined into one figure or score. A higher score mean more valuable animals for breeding purposes. The weight assigned to each traits depends on its economic importance, heritability, and genetic linkage to other traits. 


Litter size and Inventory in US Commercial Swine Production

  • Average pigs saved per litter was 10.58 for 2016
  1. 8.00 for operations with 1-99 hogs and pigs
    1. ave. 8.00 in 1994
  2. 10.40 for operations with more than 5000 hogs and pigs
    1. ave. 8.73 in 1994


The Pork Carcass

  • No other livestock carcass is marketed to the consumer in such a variety of products, varying all the way from sowbelly to pig's feet
  • The production of diverse pork products that meet consumer demands keeps the swine market strong


Market Classes and Marketing Pork


  • most hogs are marketed either by direct sale (directly to the packer) or through a local auction
  • Market hogs are classified and sold in four market classed based on:
    • ​sex
    • use to which the animal is best suited
    • weight


Market Classes

Barrows and Gilts

  • Barrows (young castrated male swine showing no male sex characteristics) and gilts (young female swine that have not farrowed) form the class of FINISHED MARKET HOGS
  • Weights vary from 120-300 lbs; most desirable wt. is 200-250 lbs
  • most pork for human consumption is derived from this class and graded according to US carcass grade


Market Classes


  • Sows (mature female swine or female swine that have farrowed or are pregnant at slaughter) represent the second most prevalent market class of swine. Usually culled sows or bred gilts that range in weight upwards of 220 lbs. Pregnancy reduces dressing % and results in a carcass that carries more fat than gilts or barrows.
  • pork from sows is mainly marketed for human consumption as cured pork or graded accordingly to US carcass grades


Market Classes


  • Stags (castrated males showing sexual development) are usually not marketed in sufficient numbers to warrant US grading, and are usually not used for human consumption
  • culled boars are generally castrated after culling and fed for a short time and thus fit into this class


Market Classes 


  • Boars (uncastrated males) are low in market value because a large portion of the carcass is not fit for human consumption because of the odor (skatol or boar taint)
  • manufactured by-products such as inedible grease, fertilizers, hides, and others are the main use of this class


Pork By-Products

  • All products from slaughtering other than carcass meat and lard are designated as by-products, usually averaging 30-40% of the animal's live weight
  • By-products vary from blood to glycerin for explosives, meat scraps to medicine, glue to leather, and violin strings to fertilizers


Measuring Carcass Traits in LIVE hogs

  • Hog producers of the future will require performance information on their animals prior to marketing and slaughter
  • NOTE: backfat thickness is the most useful single live animal indicator of carcass lean meat
    • backfat probe is interted through a small skin incision- invasive
    • ultrasound machines (newer machines can also measure loin eye depth and thus estimate the loin eye area- noninvasive


Swine Management

  • Swine require different methods of handling than cattle, sheep, or horses. Swine operations into one of the following catagories:
    • Feeder pig production: breeding herd, farrowing and weaning piglets
    • Finishing programs: growth and finishing of feeder pigs for slaughter
    • Farrow to Finish operations: combines 1 and 2 above
    • Purebred Operations: supplies seed stock for commercial swine herd


Feeder Pig Production

  • These operations produce weaned pigs that are sold to be grown and finished out on other farms
    • NOTE: comparatively low feed requirments but requires high level of management
  • Goals for this system include 2.2 litters per sow per yr with 10 or more pigs farrowed per litter with 8 or more being weaned and sold at 40-45lbs or more
  • not all of the 8 weaned pigs/litter will be sold, however, as the manager must select replacement gilts and boars from this group


Breeding Herd Management

  • Success depends on large litters, so a critical management time is during breeding and gestation
    • maximal litter sizes are achieved when:
      • gilts are bred at their 2nd or 3rd estrus (ovulate more eggs)
      • gilts are flushed (ovulate more eggs; feed increased 7-10 days prior to breeding and continued for 4-8 days after breeding) no value for sows!
      • gilts and sows are bred with more than one service (12-24hrs for gilts and 24-36hrs for sows after the onset of estrus)


Use of Crossbreeding in Commercial Swine Operations

  • approximately 90% of the sows are crossbred in commercial herds
  • crossbred pigs are stronger at birth and grow faster; thus more and heavier pigs are marketed
  • crossbred sows produce larger litters


Multiple Farrowings

  • swine producers have gone from seasonal farrowings twice a yr to multiple farrowings (throughout the yr)
  • maximal use of buildings and equipment
  • steady productions of feeder pigs
  • prevents sharp price increases which consumers dislike
  • Sows that farrow within 7-10 days of each other are rotated together
  • Witha 48 day rotation schedule, sows are given 35 days from farrowing to weaning, 3 days for adjustment of pigs, 5 days for cleanup, and 5 days for bringing in new sows prior to farrowing
    • NOTE: disadvantage- buildup of pathogens


Management of Farrowing Sows

  1. sows should be dewormed and sprayed for parasites app. 2-3 weeks before expected farrowing
  2. Farrowing house should be disinfected prior to bringing in the next group of sows- all in all out
  3. move sows to farrowing crates approximately 4-5 days prior to expected day of farrowing
  4. successful swine producers are present at farrowing no matter what time of day or night it may occur


Within a Few Days After Birth

  1. clip the needle teeth
    1. there are 8 needle teeth- 2 are located on the top jaw and 2 on the bottom jaw on each side of the head
    2. if the piglets are less than 2 days old, completely cut off teeth close to the gum
    3. if piglets are 2 days or older, only cut off 1/3-1/2 of each tooth


Castrate Male Pigs

Castration should be done within 3-14 days of birth


Injection of Iron Dextran

Piglets farrowed in confinement with no access to soil may experience iron- deficiency anemia within 7-10 days of birth (lack of hemoglobin)

Inject each piglet in the neck muscle with 100-150 mg of iron dextran within the first 3-4 days of life and give a second injection 14 days later


Right ear Notch

Litter number


Left ear notch

individual piglet number


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Know how to do this shit


Finishing program

No breeding stock, so less management and time is required, but you need a large quantity of reasonably priced feed



Farrow to Finish operations

combines the feeder pig production with finishing

advantage- no sharing of profits



Purebred operations

supply the seed stock for the commercial swine herd

breed associations have set up methods of evaluating purebred sows

certified litter is a PR litter that has carcass evaluations of 2 pigs slaughtered at 242lbs or less


Swine Nutrition

  1. 10 essential amino acids
  2. B complex vitamins
  3. additional fatty acids

55-80% of the total cost of producing pork is feed

Lysine is considered the rate limiting amino acid in swine

corn is the most common cereal grain fed to swine, however milo, barley, whear, and by-products from these grains are used by US producers

Next to common salt (NaCl), calcium is the most needed minderal in a pigs diet


Pigs in UW Barn







UW Pigs

In crates?

In lots?

In crates for 3 weeks

In dirt lots the rest of time


Average Body Temp



Temp in Barns

65-67 deg Far. 

Cool enough that babies will go to heat pens


Nursery temp



Gestation length

114 days


Water under crates

crates are 15" off the ground, and water gets flushed Mon. Wed. and Fri.


Where to give shots? Where to not give shots?

Never give shots in muscle or ham.

Give halfway down between neck and backbone (behind ear and infront of shoulder bone)


UW oxy injection

45min-1hr inject with Oxy. 

will clear system and cause uterus to work. Keeping it clean. Decreases mastitus.


Babies are at risk for chillling for?

4-5 days


UW sire

out of Hillbilly Bone--> small BW


UW 21 day litter wgt. requirements

Won't keep weight over 150 lbs