In the last 10 years, EBVs have proven their benefit to NSIP breeders through documented improvements.
- NSIP Polypay breeders have increased the breed average for pounds of lamb weaned per ewe by 13 pounds.
- NSIP Suffolk breeders have increased the market weight of lambs at 120 days of age by 6 pounds per lamb while increasing loin eye muscle and reducing fat deposition.
- NSIP Targhee breeders have increased the number of lambs born by 7%.
- NSIP Katahdin breeders have increased weaning rate by 5% and are leading the national effort to develop resistance to internal parasites.
Understanding EBVs
Animals with higher EBVs for:
- number of lambs born indicates that female progeny should conceive a higher percentage of lambs.
- number of lambs weaned indicates females with stronger maternal traits which contribute to lamb survival, plus progeny with higher vitality and survivability.
- maternal weaning (milk) weight indicates that lambs will be heavier at weaning due to a contribution of maternal traits, including milk production and mothering ability.
- post weaning weight indicates that progeny that will be heavier at market/finished weight.
- yearling grease fleece weight indicates that progeny should produce heavier fleece weights.
- yearling staple length indicates progeny that should have longer stapled fleeces.
- eye muscle depth indicates that lambs should have larger loin eye muscles. Increasing ultrasound-measured loin-muscle area one square inch should increase gross carcass value by approximately $10.
Animals with lower EBVs for:
- yearling fiber diameter indicates progeny that should have finer fleeces.
- yearling weight indicates progeny that have lower mature weights and therefore, less associated maintenance costs.
- fecal egg count indicates progeny that resist parasitic infection, thereby reducing the need for deworming.
- fat depth indicates progeny that will be leaner at market weight, but replacements ewes might also have lower reproductive capabilities