Improved Estrus Synchronization and Pregnancy Rate by Natural Mating in Murcia-Granada Goats under Extremely Hot Climate of Southern Iran

Despite the seasonal nature of reproduction in goats, creating a capacity that enables getting goats pregnant throughout the year is of economical importance in commercial settings. The objective was to compare natural and artificial (hormonal) methods of estrus synchronization on pregnancy rate of Murciano-Granadina goats under extremely hot climate of southern Iran. To synchronize estrus, experimental goats received one of three treatments. The first group (n = 123) was treated with CIDR (intravaginal progesterone release) on day-0 and which was later removed on day-19 plus PMSG injection followed by introduction to bucks on day-21. The second group (n = 157) was treated with CIDR on day-0 and with PMSG injection on day-17, then CIDR removed on day-19 followed by introduction to bucks on day-21. The third group (n = 257) did not receive any hormonal treatments and were only synchronized naturally via introduction to bucks (natural mating). Findings revealed that natural synchronization (male effect) resulted in significantly greater pregnancy rates compared to the second group (69 vs. 53%, P < 0.05). The first group tended to have greater pregnancy than did the first group (63 vs. 53%, P < 0.10). Improved reproductive performance of dairy goats under hot stressful climate signifies the economical importance and practicality of natural mating as an effective method of estrus synchronization in commercial goat production.

Keywords:

Estrus synchronization , Murciano-Granadina Goat , Pregnancy , Hot climate