Bovinos da raça canchin submetidos a duas estações de monta: Estudo comparativo dos resultados ponderais

Canchim breed calves, born at the Estacao Experimental de Sao Carlos, State of Sao Paulo, Brazil, were weighted every month, from birth until 720 days of age. A total of 385 calves, being 190 males and 195 females, born in two differents breeding seasons, wet (October-January) and dry (April-July), in three consecutive years, had its weight compared according to bull, season and year effects. Year effect based on the breeding season from 1971 to 1973 was significant (P ≤ 0.01) for weights at 4, 12 and 24 months of age and (P ≤ 0.05) for body weights at 7 and 18 months of age. Although some confounding was found with sire and year-breeding season there was a significant effect of sire at 7, 18 and 24 months of age (P ≤ 0.01) and at 4 months of age (P ≤ 0.05). Males were heavier than females at birth (P ≤ 0.01) and at 4 months of age (P ≤ 0.05). The breedmg seasons effects studied were significant (P 0.05) for weight at 4 months of age and (P ≤ 0.01) for weights at 7, 18 and 24 months of age. From birth to seven months of age the from weat season weighted 20.2 kg more than those from the dry season. At 12 months of age all females showed similar weights, however, at 24 months of age females from dry season weighted 35.3 kg more than those from weat season.