What is NSIP?

Some Katahdin sheep producers participate in the National Sheep Improvement Program, (NSIP). It is a program developed to help determine genetic evaluation through performance records to predict economically important traits.  Those traits are referred to as Estimated Breeding Values or EBVs. Those traits are referred to as Estimated Breeding Values or EBVs.  They are measurements of economically important traits that are heritable such as growth, milk production, prolificacy, mothering ability and parasite resistance.  An EBV is a predictor of the genetic merit of the individual animal itself.  The use of EBVs along with visual appraisal help us stay focused on an animal that not only looks good, but is also of increasing genetic values as well.

“EBVs are science-based, industry-tested measurements of heritable traits that can be tracked and measured. For those familiar with Expected Progeny Differences (EPDs) used in cattle, EBVs are very similar. EPDs denotes the breeding value of an individual animal’s progeny whereas EBVs denote the value of the individual animal. More simply, EBVs equal EPDs times two.”

National Sheep Improvement Program

Traits Tracked In Katahdin Sheep Within NSIP with EBVs

  • (BWT) Birthweight
  • (WWT) Weaning Weight
  • (YWT) Yearling Weight
  • (PFEC) Postweaning Fecal Egg Count
  • (PFAT) Postweaning Fat Depth
  • (NLW) Number of Lambs Weaned 
  • (MWWT) Maternal Weaning Weight
  • (PWWT) Postweaning Weight
  • (WFEC) Weaning Fecal Egg Count 
  • (PEMD) Postweaning Loin Muscle Depth
  • (NLB) Number of Lambs Born
  • USA Hair Index 

We utilize NSIP data as one of the selectin criteria in our rams that we use for genetic improvement.