Effects of breed, age of dam, birth year, birth season and sex on weaning weight of beef calves

Weaning weights of 442 beef calves (223 male and 219 female), born between 1997 and 2004 from cows of nine breeds (Hungarian Fleckvieh, Hereford, Aberdeen Angus, Red Angus, Lincoln Red, Charolais, Limousin, Blonde d' Aquitaine and Shaver) and maintained in the same conditions on peat-bog soil pasture at Keszthely, were evaluated. The effect of breed, age of dam, year/season of birth and sex of calf on the 205-day weaning weight was computed by analysis of variance (GLM). Overall mean of the 205-day weaning weight of all calves was 193 kg. The contribution to the total phenotypic variance of the 205-day weaning weight was: 18.60% by breed, 2.79% by age of dam, 43.23% by birth year, 3.95% by birth season and 31.43% by sex of calf. The evaluated factors had a significant (P < 0.05) effect on 205-day weight. Mean values by breeds were 198, 163, 206, 205, 182, 204, 181, 189 and 204 kg, respectively. According to the age of the dam, the weaning weight increased up to 5 years and after the maximum (205 kg) decreased. The minimum values were found in the group of 2- (178 kg) and 12-year-old (174 kg) cows. With respect to birth year, the highest weaning weight (238 kg) was observed in 2002 and the lowest (151 kg) in 1999. For birth season, winter, spring, summer and autumn, the 205-day weaning weight was 183, 196, 203 and 190 kg, respectively. Male calves reached 202 kg and female calves 185 kg mean value of the adjusted weaning weight.