Factor influencing sex ration in Brown swiss cattle

Abstract

Data for the birth records were collected from Brown Swiss cows raised at the Regional Agricultural School in Van, Tiirkiye. The sex ratio (% male birth) was 0.55±0.06. Season of birth had nonsignificant effect on sex ratio, but there were some differences between seasons with sex ratios ranging from 0.45±0.09 (autumn) to 0.61±0.06 (winter). Parity had nonsignificant effect on sex ratio, but there were some differences between parity with sex ratios ranging from O.46±O.08 (first) to O.70±0.27 (ninth). Year of birth had nonsignificant effect on sex ratio, but there were some differences between parity with sex ratios ranging from O.80±O.36 (1969) to O.35±O.11 (1981). The heritability of sex ratio was found to be O.056±O.079 and O.045±0.002, whereas repeatability was 0.066.