Abstract
The Kalahari red goat (KRG) was introduced into Nigeria in September 2011 with the aim of improving the growth rate, body weight and milk production of the indigenous breeds. Evaluation of some reproductive parameters of the breed will enhance the selection and breeding of the goats. This study investigated the estrus response of thirty, 2-3 year old female KRG following administration of double injection of PGF2α with the aid of aproned bucks. Changes in vulva biometry, vaginal cytological pattern and changes in some reproductive hormones of female KRG administered-PGF2α were also investigated with the aim of using such as a predictor of estrus. Data was analyzed ,using one way analysis of variance (ANOVA) and Duncan multiple comparison test of the statistical package for social science (SPSS 20). Significant difference (P<0.05) was observed between superficial cells in proestrus, estrus and diestrus (13.14±7.60, 49.73±7.64, 5.38±6.05). The difference in the mean titre for progesterone during Proestrus (5.33±2.75), estrus (3.83±0.76) and diestrus (24.50±11.03) was also statistically significant (P<0.05) while the differences in luteinizing hormone and estradiol during the three stages of the estrous cycle was not significant (P<0.05). The mean value of both vertical and horizontal diameters of the vulva was highest at estrus, followed by proestrus and lowest at diestrus. Onset of estrus in the KRG was found to be between 72 and 96 hours after administration of second dose of PGF2α. Duration of estrus in the KRG was found to be between 36 to 48 hours. The results suggest that administration of two injections of PGF2α (5mg) at 10days interval is effective for synchronization of estrus in KRG and vaginal cytological pattern can be used to determine estrus in the KRG.

Key words: Kalahari, ProstaglandinF2α, Estrus, Vulva biometry.