A19: . Breeding goals and traits of sheep production, types, usage and products. Flashcards
List the uses of shee
Use of Sheep:
-> Wool
-> Meat: Mutton + Lamb
‣ New crop lamb (15 kg)
‣ Light lamb (25 kg)
‣ Heavy lamb (40 kg)
-> Sheepskin
◦ Clothes
◦ Footwear
◦ Rugs, Etc.
-> By products
◦ Tallow → candle and soap making
◦ Gelatin
What are the results of trait-based selection influenced by?
Inheritance (heritability, repeatabilty) of characteristics.
Correlations btw characteristics.
What maternal effects carry over?
pregnancy,
twins,
multiple births,
birth weight,
viability,
milk-suckling
live weights:
birth weight of lambs?
weaning weight?
weight at 6 months?
fully mature weight?
Birth weight of lambs (2-4kg),
Weaning weight (30-day weight: 14-17kg),
Weight at 6, 9 months, yearling, mature adult (30-40 kg, 60-130kg, ram 30-40% more)
What is the daily weight gain?
100-600g/day,
ram 15-20% more
What is the specific feed conversion of sheep?
Rate of gain/ unit feed consumed (specific feed conversion): 3.2-3.7kg/kg.
rams are better.
What are traits of the carcass?
- Carcass weight
- Carcass quality (colour, tenderness, flavour, palatability).
- Degree of fatness; -Back fat thickness over loin eye (23%).
- Fat around kidneys.
- Tallow (fat), bone, lean %.
- Valuable ratio (primal cuts):
o Shoulder o Rack o Loin o Legs - Loin (and back) ratio (wide, muscular loin, loin eye area, body length, marbled intramusc. Fat).
- Carcass: neck, fore shank, shoulder, breast, rack, loin, flank, legs(extreme muscling, muscular hypertrophy, CLPG).
What are the traits of fine wool and fur?
- Grease (fleece weight): 4 - 8kg
- Wool (clean fleece weight)
- Wool thickness
- S/P ratio = secondary: primary follicle ratio)
- Fineness → length & diameter of fiber (20 - 33 microns).
- Medullation of fiber
- Crimps
- Staple (combing fiber) 5 - 15cm
- Curl type and size.
- Cashmere & angora goats: Mohair, pashmina.
wrinkles or skin folds.
fibre length and diameter: 40 - 60 microns, coarse and carpet wool.
What are the milk production traits in sheep?
- Milk yield
- Lactation performance:
o Sheep 80-300 (600) L
o Length of lactation 150-200 days - Daily milk yield
- Milk fat % -high
- Milk protein % -high
- Ease of milking (milking machine), dairy sheep: machine milking
- Udder size & form