5. Small ruminant production and husbandry Flashcards
What are some mountain breeds of sheep?
Rough fell
Welsh mountain
Scottish blackface
Swaledale
What are some hill breeds of sheep?
Lleyn Clun forest Kerry hill North Country Cheviot South country cheviot Exmoor horn
How are lambs managed on a hill farm?
Look for little more than 1 lamb per ewe per year
Hill ewe bred pure for 3-4 lamb crops
Castrated hill lambs are sold for meat + entire male lambs are kept or sold for breeding
Ewe lambs are retained as flock replacements
What are draft ewes?
Hill ewes often sold after several crops of lambs
Will often have more productive seasons in less harsh conditions
Crossed with long-wool tups to produce halfbreed ewes
What are some breeds of longwool sheep?
Teeswater
Wensleydale
What is a halfbred?
Longwool x mountain/hill i.e.
- masham
- Welsh halfbred
- Scottish halfbred
- Scottish mule
What are benefits of using halfbreds?
Hardiness and good mothering ability from mother; frame size prolificacy and milk production from father
Heterosis
Aim for 2 lambs per ewe per year
Crossed with a terminal sire to produce fat lambs
What are some down breeds & continentals (the terminal sires)?
Suffolk Charollais (France) Oxford down Beltex (Belgium) Hampshire down Texel (Netherlands)
What are some benefits to using the terminal sires?
Rapid growth rates
Good carcass conformation
Hardiness less important
What are advantages to using the stratified system?
Sheep matched to the land type
Productive utilisation of marginal land
Productive life of hill ewes extended
Benefits of heterosis in mules/halfbreds
What are disadvantages to using the stratified system?
Increased movement of sheep can equal higher disease spread
Open flocks - compromised biosecurity
Cross breeding, no control of maternal line, open flock - limited genetic improvement
What are some alternative modes of production?
Store lambs
Closed single breed flocks (Lleyn, Romney, Easycare)
Crossbreed flocks (Lleyn x Texel)
Crofting
Direct hill/upland x terminal sire production
What is fat lamb production?
Lambs sold for slaughter are around 45kg liveweight
Lambs sold through markets are sold liveweight
Lambs sold to slaughter may be sold either liveweight or deadweight
How are carcasses valued based on conformation?
Scored on a scale E,U,R,O,P from excellent to poor
Conformation is determined largely by genetics and nutrition
How are carcasses assessed based on fatness?
Scored 1,2,3L,3H,4L,4H,5, determined largely by nutrition with genetics and disease also playing a role
What are other factors affecting carcass value?
Total or partial carcass condemnations - abcesses - arthritis - T.Ovis cysts Liver condemnations - F.hepatica, T.hydatigena, E.granulosus and abcesses Dirty animals
How do lamb prices fluctuate?
Prices vary with supply and demand (both export and domestic)
prices peak at easter as most sheep are lambing
Trough in summer when there are lots of spring born lambs
Weather impacts supply, health of the wider economy impacts demand
What are factors affecting profitability?
Variations in variable costs (grain prices, availability of straw, replacement costs)
Fuel price variation
Labour availability and cost
Disease
What separates the most profitable from the rest is there ability to achieve optimum productivity from there system
What are important timings in the sheep year?
Gestation = 147 days Weaning = 12-16 weeks Scanning = 45-90 days of gestation Birth 1st mating = 18 months (lambing as a gimmer) - 7 months for a ewe lamb Birth - slaughter - 4 months (fat lambs) - 9 months (short - keep store lambs) - 12 months (long - keep store lambs)
What is tupping?
Sheep are short day breeders (seasonally polyestrus)
Increased darkness, increased melatonin & GnRH release = return to cyclicity (females), increase in testes size & sperm production for males
Mountain/hill breeds - peak fertility october/november and december
Terminal sires - longer breeding season (Dorsets all year round)
How is tupping managed?
Oestrus cycle approx. 17 days Tups usually left in for 2 cycles Raddle marks, keel paint - identifies ewe as tupped - planning of lambing - identifies return to oestrus (non-pregnant) Tup-Ewe ratio varies - 1:50 for tups - 1:20 for tup lambs/non-synchronised single sire groups - 1:10 for synchronised lambs
What are the reproductive targets that should be met?
BCS score at tupping (scale 1-5): 2.5-3 for hill, 3.5 for lowland
Conception rate 90%
Barren rate 2%
Scanning %: lowland 200% - 220%, Hill 120%
