RESUMO
One hundred and thirteen inseminations were performed for which rectal temperatures were taken at the time of inseminations. Climatological factors were also recorded daily. Pregnancy diagnosis by rectal palpation was carried out 3 months post-insemination. Pregnancy rates for all services were related to selected climatological measurements and rectal temperatures. The results obtained indicate that elevated rectal temperature, mean maximum and mean minimum temperatures and relative humidity were detrimental to conception. The effect of the climatological factor on conception is compounded by feed scarcity during the dry periods of the year.
RESUMO
A seasonal effect was demonstrated on the occurrence of oestrus and on the length of oestrous cycles in Bunaji and Bokoloji cows. There was a gradual lengthening of oestrous cycle which resulted in fewer cycles occurring in the dry and pre-rainy seasons. Oestrous cycle length was the same for Bunaji (22.89 +/-0.70 days) and Bokoloji (23.76 +/- 0.65 days) cows (P less than 0.05). Season had an equally depressing effect on the duration and intensity of oestrus in both breeds of cows. During the dry and pre-rainy seasons the behavioural signs of oestrus were poorly manifested and lasted for only a short period. During the rainy and pre-dry seasons, the duration of oestrus and behavioural signs were much more pronounced.
