Factors affecting reproductive performance in dromedary camel herds in Saudi Arabia.

A survey of 7122 dromedary camels in 115 herds in Saudi Arabia was used to estimate the effects of herd size (HZ;  100 camels), herder/camels ratio (H/C; 1: 50), manager experience (ME;  10 years), male/females ratio (M/F), housing system (HS; free vs. closed vs. mixed), length of the breeding season (winter vs. winter and spring vs. fall, winter and spring), age at first mating (3 vs. > 3 years), and time of mating after parturition (≤ 3 vs. > 3 months) and their interactions on the overall pregnancy rate. Barren females of these herds (n = 886) were examined for the causes of infertility. Results showed that herds with H/C of 1: 50 (72.79%) (p = 0.003). Herds having ME of > 10 years revealed greater overall pregnancy rate (94.89%) than herds with ME of 5-10 years (80.54%) and those with ME of < 5 years (72.5%) (p = 0.001). There were significant interactions between H/C × HZ (p = 0.003), H/C × HS (p = 0.006), and ME × HS (p = 0.02). The overall pregnancy rate did not significantly differ between herds bred females by age of 3 years and those bred females by age > 3 years and in females bred within 3 months after parturition and in those bred after 3 months. The mean calving interval was shorter (p = 0.008) in camels mated within 3 months of parturition (15.25 ± 2.8 months) than in those mated after that time (24.33 ± 6.5 months). Clinical endometritis, ovarian hydrobursitis, and vaginal adhesions were the common clinical findings in barren females. Thus, efforts to reduce the age at first mating and the interval after calving, increase the number of herders/camels, and control reproductive disorders could improve the reproductive performance and quality of camel herds in Saudi Arabia.