Selenium + Vitamin E Supplementation in Anestrus Goats: A Strategy to Enhance Reproductive Outcomes Under a Semi-Arid Production System

Goats are primarily raised in marginal, arid, and semi-arid production systems and exhibit a seasonal reproductive pattern. Extending their reproductive season would enhance food security and improve the economic viability of goat production. Therefore, the objective of this study was to assess the effects of SeVE supplementation during the anestrus season on ovarian activity in anestrous goats subjected to an estrus synchronization protocol. The response variables included estrus induction (EI), ovulatory rate (OR), corpus luteum diameter (CLD), left and right ovary diameters (LOD and ROD), embryo implantation (EMBRYO), and pregnancy rates (PREG). Adult, anestrous, crossbred dairy goats (<i>n</i> = 32) from northern semi-arid Mexico (i.e., Comarca Lagunera, 26° N) were randomly assigned to two homogeneous groups based on age, live weight (LW), and body condition score (BCS): (1) the supplemented group (SeVE; <i>n</i> = 16), received 5 mg selenium plus 350 IU vitamin E, and (2) the control group (CONT; <i>n</i> = 16), received physiological saline. Estrus was induced using a combination of progesterone (P4, 20 mg), equine chorionic gonadotropin (eCG, 400 IU), and exposure to the male effect. While no differences (<i>p</i> > 0.05) were observed between the groups for LW and BCS, the variables EI, OR, EMBRYO, and PREG rates were higher (<i>p</i> < 0.05) in the SeVE group than the CONT group. No differences (<i>p</i> > 0.05) were observed between the groups for CLD, LOD, or ROD. Thus, SeVE-targeted supplementation improved reproductive outcomes without affecting ovarian structure size (i.e., a non-dimensional ovarian SeVE action), suggesting that this precision supplementation strategy certainly enhances reproductive efficiency. This was possibly related to selenium-induced increases in P4 synthesis, and the antioxidant effects on follicular development correlate with improved endometrial development, conceptus survival, embryo growth, and pregnancy maintenance. Such improvements could contribute to the sustainability of marginal production systems in the semi-arid regions of northern Mexico, supporting food security and increasing economic returns for goat producers and their families.