Crossbreeding of Holstein Friesian, Brown Swiss and Sanga breeds in Zaire. II. Growth rate, calving interval and body size

Abstract

The analysis involved 332 records of body measurements (liveweight: LW, depth of chest: HG, width of rump: HR and wither height: WH) and calving intervals and 147 records of growth data from a crossbreeding experiment between Holstein Friesian, Brown Swiss and Ankole cattle at the Lushebere farm in the Masisi zone, North-Kivu in the Republic of Zaire. A significant positive Holstein Friesian additive effect was found for LW. For LW, large positive individual heterosis effects were found for Holstein Friesian x Ankole and Brown Swiss x Ankole crosses. For calving interval, the Holstein Friesian and Brown Swiss additive effects were significantly favourable. Individual heterosis for calving interval of Holstein Friesian x Ankole and Brown Swiss x Ankole was significant and reduces the calving interval. Low heritabilities were found for growth rate (0.07). The heritability estimate for calving interval was 0.26. Higher heritability estimates for depth of chest (0.31) and live weight (0.36) were observed. Medium estimates were found for wither height (0.19) and width of rump (0.29). The genetic correlations between milk yield and body measurements were: 0.63 for wither height, 0.57 for depth of chest, 0.61 for width of rump and 0.76 for live weight. The genetic correlations between body measurements were: 0.83 for WH and HR, 0.41 for WH and LW, 0.81 for HG and HR, 0.79 for HG and LW and 0.80 for HR and LW.