Analysis of milk productivity and methane emissions of dairy cattle breeds in the farms of the leningrad region

Abstract

The article presents a comparative analysis of three common breeds of dairy cattle in the Leningrad Region – Ayrshire, Holstein and Black-and-White in terms of average annual milk yields per head, milk fat and protein content and methane emissions. The indicators were compared by a method, which tested the hypothesis of the equality of two means at the level of some error (5%). Holstein cows had the highest annual milk yields; those of Black-and–White cows were 15.24% lower in average, and those of the Ayrshire breed were 26.64% lower. The Ayrshire breed demonstrated the highest milk fat content; the Holstein and Black-and-White breeds – 1.07 and 1.08 times lower, respectfully. The best average protein content was 3.27% in the Ayrshire breed; the Black-and-White breed had 1.03 times lower protein content, and the Holstein breed had 1.04 times lower protein content. The Holstein breed had the highest methane emission of 0.185 t/head/year. Based on the indicators of productivity and milk fat and protein content, it seemed reasonable to divide all the farms in the Leningrad Region that worked with the considered breeds into 4 groups by applying a discriminant analysis. With a more detailed analysis of both individual breeds and when they are considered together, it makes it possible to determine the effectiveness of their housing on a farm at the regional level.