PREVALENCE OF REPEAT BREEDING AND ITS EFFECTIVE TREATMENT IN COWS AT SELECTED AREAS OF BANGLADESH

Abstract

The objectives of the study were to determine the prevalence of repeat breeding and its associated risk factors in cows at selected areas of Bangladesh followed by determination of an effective treatment regime for those cows. Data were collected by interviewing the owner of the cows from 172 farms having 1524 breedable cows located at one Upazila of Mymensingh, Chittagong, Khulna, Satkhira, Bogra and Dhaka districts. A total of 122 repeat breeding cows were treated and randomly distributed into 5 experimental groups for different treatment regimes. The treatment regimes were (i) single AI with injection of 500 µg of gonadorelin, (ii) intra uterine infusion of 4.0 million i.u. penicillin daily for 3 days followed by single AI at next estrus, (iii) same time AI with double doses of semen, (iv) two times AI at 8 hours interval and (v) single AI without any intervention (used as control group). Information was collected for all treated cows for returning to estrus at 20-22 days post-AI. If the cow did not return to estrus at 20-22 days post-AI, the cows were examined for pregnancy by per rectal palpation of genital tract at 60-90 days post-AI. The pregnancy of the treated cows was used as the indicator of success of each treatment regime. The overall prevalence of repeat breeding in cows was 11.5%. The breed of cows, herd BCS and farm size influenced the prevalence of repeat breeding in cows. The age, parity, BCS and milk yield influenced the occurrence of repeat breeding in individual cows. The significantly higher proportion of cows recovered when AI was done using double doses of semen (52.8%) or single AI was done with GnRH administration (51.9%) than no intervention control (30.4%). In conclusion, repeat breeding cows may be inseminated with double doses of semen or with single AI with GnRH administration for improvement of conception.