Vol. 10, Special Issue 9 (2021)

Author(s):
US Khinda, SS Dhindsa, M Honparkhe, VS Malik and Prahlad Singh

Abstract:
Sahiwal is considered as best indigenous milch breeding the country. The present study was conducted on non-pregnant, clinically healthy Sahiwal cows (n=40, >45 days in milk) weighing between 350 to 500 kg having apparently normal estrous cycle and genitalia. All cows were divided into 3 groups on the basis of treatment used or not viz. Group I (Modified Presynch-Ovsynch, n=15), II (Modified Presynch-Heatsynch, n=15) and III (Spontaneous estrus, n=10). In treatment groups, considerable number of cows (66.67-93.33%) showed main signs of behavioural estrus at the time of insemination. On the other hand, only 50-70 percent animals that were inseminated at spontaneous estrus exhibited major estrus signs. Further, all cows that became pregnant later following hormonal treatment showed bellowing, frequent urination, vulvar swelling and CVM. In treatment groups, moderate and high uterine tones were observed in 33.33 to 37.50 and 62.50 to 66.66 percent subsequently pregnant animals, respectively. In conclusion, a positive relationship between estrus expression and subsequent pregnancy rate was observed in the study. Hence, positive conception may be projected if an animal displays main heat signs at the time of insemination like swelling of vulva, bellowing, tonicity of genitalia and vaginal discharge.