The Effect of Phenotypic and Genotypic Factors on Some Yield Traits in Holstein Friesian Cows with High Milk Yield Reared in Türkiye

Abstract

This study was carried out to determine the effects and phenotypic relationships of some environmental factors (first calving age, calving year, and calving season) on Lactation period, dry period, milk yield and Milkability traits. The material of the study was the lactation records of 1079 Holstein cows raised in a private dairy farm. As a result of analyses, the values of 305-DMY yield (305 DMY), the lactation period (LP), dry period (DP), time to reach peak yield (Tmax), peak yield (Ymax), average daily milk yield (ADMY), total lactation milk yield (ATMY) and age at first calving (AFC) were determined as 9926.3±178.1 kg, 318.1±1.4 days, 60.05±0.9 days, 95.2±2.1 days, 42.3±0.3 kg, 32.2±0.3 kg, 10248.7±94.1, and 26.7±0.2 months, respectively. The study found the average milk flow rate (MFR) and the average milking time (MT) as 2.0±0.0 kg min-1 and 360.9±4.7 seconds, respectively. In addition, estimates of the 305-day mature equivalent milk yield (ME 305-d) and MFR were also found to be 0.41±0.24 and 0.51±0.30, respectively. As a result, this dairy farm can be recommended as an example to breeders who have just started their dairy farm in Türkiye and countries with similar environmental conditions and are looking for a model.