Abstract: The purpose of this study was to estimate the trends components of 305-days milk yield in Holstein Friesian Cattle Holstein cows raised at the Ceylanpinar state farm in Turkey between 1986 and 2007 years. The phenotypic, genetic and environmental trends for 305-days milk yield were found to be 106.91, 13.42 and 93.49 kg year-1, respectively. Despite, there was a correct decision in selection environmental factors affected yield more. In this respect, continuing the improving environmental factors which is composed of maintenance, feeding, milking practices and barn is recommended.
Galip Bakir, Ali Kaygisiz and Suleyman Cilek, 2009. Estimates of Genetic Trends for 305-Days Milk Yield in Holstein Friesian Cattle. Journal of Animal and Veterinary Advances, 8: 2553-2556.