원문정보
초록
영어
A artificial insemination (AI) has been used in Uganda for over 60 years, but a small population of the total herd has been bred using this method and pregnancy rates among dairy farms is still low. This study was conducted to optimize the Ovsynch method for improving the productivity of dairy farms through AI services in Uganda. In total, 160 cows from 18 dairy farms were selected for timed-AI. Synchronization was performed according to Ovsynch protocol with low GnRH (0.15 mg) followed by AI using frozen semen from Korean Holstein (0.5 mL straws). The pregnancy rate in low GnRH group was compared with the previously reported results using normal GnRH (0.25 mg). The overall pregnancy rate in normal group was 28.2% (22 of 78), whereas that in low GnRH was 49.4% (79 of 160) (p<0.01). The previous report implied that low pregnancy rate in normal GnRH was caused by a high occurrence of abnormal estrus (54.5%, 30 of 55). Thus reducing the GnRH during Ovsynch could reduce a occurrence of abnormal estrus. Taken together, these results suggested that use of low GnRH during AI services could improve the productivity of dairy farms in Uganda.