Genetic and Genomic Evaluation of Mastitis Resistance in Canada

Authors

  • Janusz Jamrozik Centre for Genetic Improvement of Livestock, University of Guelph
  • Astrid Koeck Centre for Genetic Improvement of Livestock, University of Guelph
  • Filippo Miglior Agriculture and Agri-Food Canada Canadian Dairy Network
  • Gerrit Kistemaker Canadian Dairy Network
  • Flavio Schenkel Centre for Genetic Improvement of Livestock, University of Guelph
  • Dave Kelton Department of Population Medicine, University of Guelph
  • Brian Van Doormaal Canadian Dairy Network

Keywords:

genetic evaluation, genomic evaluation, mastitis resistance

Abstract

A nation-wide health recording system for dairy cattle was started in Canada in 2007. Eight diseases are recorded by producers on a voluntary basis, including mastitis, displaced abomasum, ketosis, milk fever, retained placenta, metritis, cystic ovaries and lameness. Mastitis is the most frequent and most recorded disease, which highlights the economic importance of this trait. A routine genetic evaluation system for mastitis resistance will be officially implemented in December 2013 for Holstein, Ayrshire and Jersey breeds. The model for estimation of breeding values for mastitis resistance is a multiple-trait linear animal model including mastitis, mean SCS in early lactation, standard deviation of SCS, excessive test-day SCC, fore udder attachment, udder depth and body condition score. EBVs for mastitis resistance are published as relative breeding values with a mean of 100 and a standard deviation of 5, where higher values are desirable.

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Published

2013-08-22