THE EFFECT OF DIFFERENT BLOODINESS LEVEL ON LATVIAN BROWN COW PRODUCTIVITY

Abstract

Latvian brown (LB) cow breed is economically most important livestock breed in Latvia. In last 5 years in Latvian farms rapidly increases Holstain black and white cow population, however LB breed cows is more resistant against environment and climate changes than relatively new Holstain breed cows. More resistant is genetic resource LB cows. In study was observed data from Latvian Agriculture data center about Latvian brown (LB) cows with different breed blood admixture. Cows, included in data base was born in time period from 2003–2007 year and closed at least 1 full lactation. The aim of the study was to determine how different amount of Latvian brown cow bloodiness affects cow productivity and longevity. Latvian brown cow milk yield significantly lower (p<0.05) was in first lactation (4826.1 kg), but it increased until fifth lactation (5891.8 kg). Opposite situation was occurred with milk dry matter content, milk fat content significantly higher was in first lactation, but until 5th lactation it decreased by 0.84%, similar situation was occurred with milk protein content. Significantly highest milk yield grouped by dominant breed bloodines was observed in group with Brown Swiss bloodiness (4887.3 ± 26.3 kg; p<0.05), but highest protein content in genetic resources group (4.31 ± 0.02 %). Average lifespan in LB cow population was 2463.0 days (in average 6.7 years or about 5 lactations.