Some Milk Yield Traits and Related Gene Expressions of Holstein Cattle Raised in Kocas Agricultural Enterprise

The aim of this study was to investigate some milk production traits and milk production related gene mRNA transcript levels of Holstein cows in the conditions of Aksaray Rocas agricultural enterprise and to investigate the effects of some environmental factors. Total 1349 milk yield record from 1377 lactation and blood samples of 324 Holstein cows raising in Kocas agriculture enterprise between 2009-2015 years were used. The least squares method was used to assess the effects of environmental factors on milk characteristics. Milk production related ATF3, CDKN1A, and PRL gene expressions were identified by using qRT-PCR. The least squares means for milk yield of 100, 200 and 305 days were 2950.51 +/- 24.79 kg, 5594.28 +/- 45.09 kg and 7923.28 +/- 80.92 kg. respectively. Lactation milk yield, lactation period and average daily milk yield was found to be 7700.02 +/- 99.17 kg, 315.75 +/- 3.67 days and 24.91 +/- 0.2 kg. respectively. According to qRT-PCR results, related gene expressions were up-regulated in high milk production cows compare to low milk production cows. According to the findings, it has been concluded that, Holstein in cows are generally positive to improve milk yield over the years and ATF3. CDKN1A and PRL genes contribute positively to marker-assisted selection and breeding programs to improve milk yield.