Determination of Milk Production Characteristics, Phenotypic, Genetic and Environmental Trends in Jersey Cattle Page

This study was conducted to determine the effects of environmental factors on milk yield traits of Jersey breed cattle reared at the Karakoy State Farm located in Samsun Province of Turkey, as well as the phenotypic, genetic and environmental trends in relation to 305 day milk yield. The Wombat software was used to estimate heritability and breeding values for milk yield. The effects of parity, season and year factors on actual and 305 day milk yields were found to be statistically significant (P<0.01). The mean values of lactation length, actual and 305 day milk yields of Jersey cattle were found as 310 +/- 5 days, 4462 +/- 90 kg and 4183 +/- 70 kg, respectively. A phenotypic trend of 29.97 kg year-1, genetic trend of 18.71 kg year(-1) and environmental trend of 11.26 kg year(-1) were estimated. The heritability of 305 day milk yield was 0.344. The overall results of this study showed that an improvement in Jersey cattle reared at the Karakoy State Farm between the years 2006 and 2014 was provided remarkably on the basis of phenotypic, genetic and environmental trends and the enterprise had a good genotype and a good management.