Hassan Arab, Samad Mosaferi and Amir Ali Kaveh
Reproduction is one of the most important issues in the dairy farms. So, there are some standards to reach the ideal production. In this survey we aimed to evaluate the CIDR and CIDR+OvSynch treatment methods in the dairy anoestrus cows. One-Hundred and fifty anestrous cows that had same body condition were divided into 3 groups. Group1 received 5ml gonadorelin. Group2 received CIDR on day-0; CIDR was removed on day-7 and 24hours later 0.5ml estradiol benzoate. Group3 received CIDR on day-0 concomitant with 5ml gonadorelin, 7 days later, CIDR was removed and 3ml prostaglandin administrated at the same time and after 24 hours were received 0.5ml estradiol. Finally, cows were inseminated artificially. Conception and pregnancy rate were recorded and analyzed. Results showed that in group-1, after 14 days, 18 were estrous so that after insemination, 8 and 10 of them were pregnant and non-pregnant, respectively. So that, fertility rate was 44.44%. Also, in group-2, 42 cows showed estrous after 14 days and 30 days after insemination, sonographic findings indicated that 15 cows were pregnant and 27 were non-pregnant. So that, fertility rate was 35.7%. Finally, in group-3, 44 of them were inseminated after 14 days, and after 30 days, 18 of them were pregnant and 26 of them were non-pregnant. So that, fertility rate was 40.9%. Our results indicated that estrous rate in CIDR group is better than gonadorelin, but the fertility was not statistically different between groups. Thus, we can conclude that use of CIDR is better than gonadorelin.
