INFLUENCE OF THE CAPAITY OF DAIRY CATTLE FARMS UPON THE АVERAGE MILK YIELD AND AVERAGE LENGTH OF SERVICE-PERIOD

V. Gaidarska, T. Ivanova

Abstract: The aim of the study was to investigate the influence of the capacity of dairy cattle farms upon the аverage milk yield and average length of service-period. To achieve the aim of the study they were studied 41 dairy cattle farms from different regions in Bulgaria with a total of 8547 cows. According to the number of cows in the main herd, the farms were divided into three groups: first group – up to 49 cows, the second group - from 50 to 100 cows, and the third group with more than 100 cows. The study was conducted by using the following statistical tests: Kolmogorov-Smirnov Test, Shapiro-Wilk Test, Levene’s Test of Homogeneity of Variances, Welch Robust Tests of Equality of Means, Brown-Forsythe Robust Tests of Equality of Means and Kruskal-Wallis test. As a result of the analysis, it was found that the difference in the average length of service-period in the three groups of farms was significant. The shortest was the service-period in the second group (from 50 to 100 cows in the main herd) – 100 days, and the longest - in the group of farms with more than 100 cows. No significant difference was found in the average milk yield between the three groups of farms.

Keywords: average milk yield; dairy cattle-breeding; herd size; service-period

Date published: 2017-05-16