Genetic analysis of reproductive traits in Karan Fries cattle

Abstract

The present study was conducted on Karan Fries herd maintained at ICAR-NDRI, Karnal. In the present investigation on Age at first calving (AFC), Days to first service (DFS), Service period (SP), Number of services per first conception (NS/C), Pregnancy Rate (PR) and Conception Rate (CR) 624, 1793, 1921, 1933, 1921 and 1933 observations respectively were recorded. The effect of non-genetic factors on reproductive traits were studied by least-squares technique and the significant difference of means between subclasses of season, period and parity were tested. Genetic and phenotypic parameters of reproduction traits were estimated. Season of calving had significant effect on AFC, DFS, SP and NS/C. Further, period of calving had significant effect on AFC, DFS, SP, NS/C, PR and CR. Parity had significant effect on DFS, SP and PR in HF crossbred cattle. The data were adjusted for the significant non-genetic factors to remove the differential environmental effects. The heritability estimates of fertility traits viz. DFS, SP, PR, NS/C and CR were, in general, very low (0.04-0.13). These estimates indicated that these fertility traits are influenced more by managemental and environmental factors than by genetic factors.