Tropicultura (Jan 2007)
Non-genetic Factors Affecting Gestation Lenght and Postpartum Intervals in Gudali Zebu Cattle of the Adamawa Highlands of Cameroon
Abstract
The effects of non-genetic factors (sex of calf, calf birth weight, age of cow, season of calving) affecting gestation length (GL) and open days period (OP) in the Ngaoundere Gudali cattle of the Adamawa (Cameroon) was investigated. Mean GL was 293.4 ± 0.4 d. Sex of the calf significantly (P< 0.05) affected GL, with male calves being carried in utero approximately 3 days longer than the females (294.1 ± 1.2 vs 291.1 ± 1.2 d). Calf birth weight tended to increase as gestation lengthened. Parity and age of the cow had no significant (P> 0.05) effect on GL. The mean duration of the OP (from calving to conception) was 267.7 ± 7.4 d. Approximately 23.2% of the cows conceived within 90 days of calving and a total of 55.6% had conceived by 360 days. The distribution of the OP was bimodal, and could have been influenced by seasonal availability of feed, or long (6 months) mating season allowing cows to calve during the following mating season. Calving to conception interval was significantly (P< 0.001) affected by month of calving and parity. Sex of the calf did not affect significantly the duration of the postpartum period, although this period was 5 days longer following the birth of a male calf.
