Search for longevity predictors for dairy cows

Abstract

The results of researches of domestic and foreign authors were summarized in the aspect of studying the problematic issues concerning the evaluation of dairy cows on the traits of duration economic use and lifetime productivity. The researchers reported that productive longevity traits of cows largely depended on hereditary (conditional bloodliness by the improving breed when crossing, intralinear and interlinear selection, linear breeding, the degree of inbreeding, the strength of influence breeding value of ancestors) and paratypical (age at the first calving, correlative variability between linear traits and longevity) factors. In most cases, an increase the share of heredity due to absorption crossing led to reduction in the duration of productive use and lifetime productivity of cows. When studying population genetic parameters, the authors of many studies confirmed the low level of heritability of longevity traits, which did not contribute to effective selection based on the duration of productive use and lifetime productivity. Analysis of the results of these studies confirmed that linear traits of the conformation type of dairy animals can be used as early indirect predictors of longevity. This conclusion was based on the high heritability of linear traits and existence of positive correlations between them and duration of productive life.

Keywords

• predictors
• lifetime productivity
• dairy cattle
• line
• conformation type
• heritability
• correlation.