Uncorking Quantitative and Qualitative Seminal Traits in French-Alpine Bucks via Carbetocin Stimulation to Enhance Goat Production in Semi-Arid Environments.

Abstract

Optimizing semen collection is critical for maximizing genetic advancement and reproductive efficiency in livestock. While exogenous hormones can enhance ejaculate quantity and quality, short windows of biological activity often limit their efficacy. This study was conducted in northern-arid Mexico (25° N, 103 W) to evaluate the comparative effects of oxytocin (OXYT) and carbetocin (CARB) administration on semen quality in French-Alpine bucks. Males (n = 12) were allocated into three groups and received intravenous treatments 10 min prior to artificial vagina collection: (1) OXYT (10 UI oxytocin buck^-1), (2) CARB (0.2 mg 100 kg^-1 LW^-1), and (3) CONT (1 mL saline buck^-1). The same bucks received all three treatments separately. CARB outperformed both groups (p ≤ 0.05), improving all evaluated parameters (p ≤ 0.05): ejaculated volume (i.e., increased by 103%), sperm concentration, mass and progressive motility, total sperm count, viability, normal morphology, plasma membrane functionality, acrosome integrity, and chromatin dispersion. Crucially, CARB doubled (p ≤ 0.05) the available projected or theoretical number of doses for intravaginal artificial insemination (POTNDIAI), followed by the OXYT and CONT groups, with 11.14 POTNDIAI each. Therefore, CARB emerges as a highly effective, accessible pharmacological strategy for semen collection protocols, substantially enhancing sperm yield and structural quality in breeding bucks. Ultimately, by bridging advanced reproductive physiology with practical smallholder farming, this methodological optimization provides a viable strategy to enhance reproductive efficiency and long-term sustainability in small ruminant production systems within arid environments.