Evaluating the Efficiency of Artificial Insemination Following Estrus Synchronization of Dairy Cattle in Southern Region, Ethiopia: The Case of Dale District

Abstract

The aim of this study was to determine the success rate of artificial insemination following oestrus synchronization and determining associated factors on pregnancy rate of cows/heifers in Southern Ethiopia. A sum of 171 cows/heifers was synchronized with PGF2α.and as a result 97.7% synchronization rate was obtained. All sampled cows inseminated at standing estrus using frozen semen of Holstein Frisian. Pregnancy diagnosis was carried out at day 90 post AI by rectal palpation and a pregnancy rate of 60.4% was obtained. The average number of services per conception was 1.75. The optimum conception observed among the cows inseminating between 9 to 14 hours (71.6%) after the onset of estrus. Cows/heifers with body condition score (BCS) 6 showed higher (P<0.05) pregnancy rate when compared to BCS of 5.5 and 5. Similarly, cows/heifers with BCS of 4.5 had lower conception rate. Cows aged 5 to 7 and 3 to 4 had comparable high pregnancy rate while, cows aged 8 to 9 had significantly lower pregnancy rate. The rate of conception was varied (P<0.05) across the bulls from 53.9% to 69.9% among the bulls. In conclusion, factors such as time of insemination, body condition score, age, genotype and bull ID have significant effect on pregnancy.

Keywords: artificial insemination, body condition, pregnancy rate, synchronization, time of insemination, Dale