Comparative efficacy of single-dose versus multi-dose FSH regimens in dromedary camels: Assessment of ovarian response, embryo yield, endocrine profiles, and molecular signatures

This study aimed to compare two donor superovulation protocols (SOP) and embryo transfer (MOET) technology in dromedary camels by analyzing the mRNA gene expression of osteopontin (OPN) and vascular endothelial growth factor (VEGFA), in conjunction with follicular activity, embryonic development, and hormonal profiles. Ten healthy female camels were assigned to two treatment groups to evaluate different superovulation regimens: a conventional 5-day protocol (5dSOP) and a simplified single-dose protocol combined with hyaluronic acid (1dSOP), both utilizing a mixture of 500 μg porcine follitropin and 100 μg porcine lutetropin. The 1dSOP treatment consistently yielded significantly higher mean follicular counts (27.2 ± 0.74 vs. 22.6 ± 0.76; P < 0.05), larger follicular diameters (1.82 ± 0.04 vs. 1.68 ± 0.05 cm), and a superior embryo recovery rate (19.29 ± 0.39 vs. 13.21 ± 0.43) compared to the 5dSOP. Furthermore, the 1dSOP resulted in significantly shorter response times (7.75 ± 0.23 days) than the 5dSOP (8.88 ± 0.27 days). A highly significant interaction between protocol and time was observed, with the 1dSOP group reaching peak follicular values at 144 and 192 hours. While no significant differences were found in OPN expression, VEGFA expression was notably elevated in the 5dSOP group, suggesting potential benefits for endometrial receptivity. In conclusion, the 1dSOP is a highly successful, simplified method that demonstrates superior follicular growth and embryo yield while enhancing animal welfare through decreased intervention and improved follicular harmonization.