Calving difficulties and calf mortality in Finnish dairy cattle population

Abstract

Genetic parameters and breeding values for calving difficulties and calf mortality were estimated from Finnish dairy population. The data consisted of 1,160,833 Finnish Ayrshire (FAY) and 289,998 Finnish Holstein-Friesian (FHF) dairy cows first, second and third parity records. The data were analyzed using multiple-trait AI-REML methods with sire-grandsire model. Model included the effects of sex of calf, gestation lenght, calving month, parity of dam, herd-year, sire of calf and grandsire of calf. The estimated heritabilities were low (0.01 0.04) for both calving difficulties and calf mortality. Both traits were estimated as an effect of sire and maternal grandsire of calf. Heritabilities were only a little greater in first than later parities. Genetic correlations between calving difficulties and calf mortality were high, 0.86 for FAY and 0.90 for FHF. More difficulties were observed when the calf was male, the gestation length was shorter or longer than normal, in winter and when the cow was a first calver.