Oestrous behaviour in Bunaji (White Fulani) heifers

Abstract

SUMMARYContinuous observations were maintained on a group of 32 White Fulani (Bunaji) heifers at three periods daily, 06.00–12.00 h, 14.00–18.00 h and 18.00–22.00 h, for 112 days, during which time all heifers were recorded for incidence of standing for mounts for a while by a vasectomized bull but for the whole period by other heifers in the group as well as soliciting for mounts. Thirty heifers were judged as showing oestrus. Of the 62 oestrous cycles recorded, 82·2% had mean length (±S.E.) of 22·4 ± 0·7 days. Average duration of oestrus (±S. E.) in 30 heifers was 3·1±0·2 h. There were no significant differences between the three observation periods for the time spent in mounting activities, the duration cf oestrus commenced at the three periods and for the average oestrous periods.It would appear that closer observation for indicative oestrus between 06.00 and 18.00 h should be valuable for the purpose of oestrus detection in an artificial insemination scheme under the Guinea Savanna condition of Nigeria.