Estrus detection in dairy cattle: Are vaginal detector probes species-specific to vaginal mucus?

Abstract

Two separate estrous detector probes, labelled for bovine and swine, were intuitively used to study changes in electrical resistivity of vaginal mucus (ERVm) in 48 Sokoto Gudali cattle (SGC) that were synchronized with double intramuscular injections of prostaglandin F 2 alpha (PGF). The cattle comprised of 32 heifers and 16 cows were randomly assigned into groups A (11-day) and B (12-day) PGF injection intervals, with equal number of heifers and cows. The ERVm was measured between first day (d 0) of PGF injection and d 15. Each injection contained 500 μg Estrumate®. Results showed that the difference in the mean values of ERVm between bovine (267.07±20.81) and swine (256.64±39.41) probes was not significant (p>0.05). Similarly, the differences in ERVm between the bovine and swine probes at 48 h post 1^st PGF in all cattle (239.20±5.09 and 231.60±13.53), as well as 48 h post 2nd PGF in 11-day (253.07±5.22 and 224.67±23.45) and 12-day (266.67±25.55 and 233.03±21.96) PGF injection groups were not significant (p>0.05), respectively. In all, 75% of cattle stood to mounting by pen mates and a 75:25 success to failure ratio for evaluating ERVm in cattle with the aid of a swine vaginal probe were obtained. The ERVm pattern also suggests that estrus occurred between 0-72 h post PGF with both probes. It can be concluded that there may be no difference in sensitivity to vaginal mucus between these two probes and that either may be used to evaluate ERVm in the SGC.