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World Trends in Dairy Cow Fertility

Thursday, August 21, 2014: 10:30 AM
Bayshore Grand Ballroom B-C (The Westin Bayshore)
Jennie E. Pryce , Biosciences Research Division, Department of Environment and Primary Industries, Victoria, Australia
Rob Woolaston , Arlie Solutions, Pullanvale, Queensland, Australia
Donagh P Berry , Animal & Grassland Research and Innovation Centre, Teagasc, Moorepark, Fermoy, Co. Cork, Ireland
Eileen Wall , SRUC, Edinburgh, United Kingdom
Marco Winters , DairyCo, Kenilworth, Warwickshire, United Kingdom
Rohan Butler , Holstein Australia, Melbourne, Victoria, Australia
Matthew Shaffer , Dairy Australia, Melbourne, Victoria, Australia
Abstract Text: Although differences exist between breeds and countries, dairy cow fertility has generally declined since around 1980. However, for many countries, an improvement in phenotypic and genetic trends for female fertility has been observed from the early to mid 2000s largely as a consequence of introducing breeding values for fertility and increased emphasis on fertility in breeding objectives. However, for some countries, fertility is still deteriorating genetically. Barriers to genetic improvement include: 1) the low heritability of fertility - genomic selection tools have helped to increase the reliability of bull breeding values; 2) insufficient selection intensity on fertility as a consequence of economic drivers of milk production versus fertility; 3) a possible association between level of milk production and the genetic correlation of fertility and milk production and 4) the impact of inbreeding on reproductive performance and increased probability of lethal recessives arising.

Keywords:

dairy cattle

fertility

genetic trend