Angeles De Santiago-Miramontes

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.

This study capitalizes on computer-assisted semen analysis (CASA) to evaluate a precision nutritional strategy integrating agro-industrial feed upcycling and functional phytogenic supplementation in rams. Black Belly rams (n = 15) sustained on an upcycled basal diet derived from dairy-cow feed rejections were assigned to a non-supplemented control group (CONT) or supplemented with Withania somnifera (WITH) or Lepidium meyenii (LEPI) at 400 mg kg⁻¹ LW d⁻¹. The 64-day trial was conducted from May to July in arid northern Mexico. Sexual drive, seminal quality, and high-resolution sperm kinematics were evaluated using CASA. Body and testicular measurements, ejaculate volume, and most categorical motility traits remained comparable among treatments (p > 0.05). However, phytogenic supplementation enhanced selected seminal and sexual-drive variables (p < 0.05). Crucially, longitudinal treatment × time interactions (p < 0.05) showed that while the CONT group experienced a seasonal decline in local mobility (LOCMOB), it increased from 1.47% to 2.01% in the WITH group, representing a 37% relative increase over time. Moreover, both WITH and LEPI increased LIN and STR by the end of the experimental period (p < 0.05), demonstrating more linear and efficient sperm trajectories. These findings highlight the productive value of upcycled dairy-cow feed rejections and demonstrate that strategic supplementation with W. somnifera or L. meyenii can refine sexual drive, seminal quality, and sperm kinematic efficiency. This integrated bio-circular strategy provides actionable insights for sustainable small-ruminant production under challenging arid summer conditions.

Nowadays, it is central to generate innovations that convert agricultural by-products and food waste into valuable animal products while promoting the long-term resilience and sustainability of vulnerable animal production systems. Nutraceuticals (i.e., ‘nutrition + pharmaceutical’) are derived from foods that offer health benefits. In animal production, nutraceutical supplementation with Withania somnifera and Lepidium meyenii has shown positive effects on the endocrine, cardiopulmonary, and central nervous systems. We aimed to evaluate the possible impact of nutraceutical supplementation on rams fed a diet based on surplus feed from a highly industrialized Holstein cow production system, on corporal (live weight [LW], kg; body condition score [BCS], units), metabolic (blood glucose [GLU], mg dL⁻¹; serum protein [PRO], g 100 mL⁻¹), and sexual–testicular variables [sexual odor (ODOR, units); scrotal circumference (SC, cm); testicular volumes (TVOL, cm³); and estimated daily sperm production (EDSP, millions)]. Black Belly rams (n = 12; LW = 70.36 ± 1.2 kg; BCS = 2.96 ± 0.03 units; age = 3.8 ± 0.2 years; 25° N) were divided into 3 experimental groups: (1) WITH, supplemented with Withania somnifera (400 mg kg⁻¹ LW d⁻¹); (2) LEPI, supplemented with Lepidium meyenii (400 mg kg⁻¹ LW d⁻¹); and (3) CONT, not supplemented. The variables LW, BCS, GLU, PRO, and SC, as well as some components of TVOL, did not differ (p > 0.05) among the main effects of treatment or time; only ODOR, right transverse testicular diameter, and total testicular volume differed among treatments, generally favoring the WITH group. Furthermore, the TRT × T interaction demonstrated superior performance (p < 0.05) in the WITH group, with the largest values for LW, GLU, PRO, ODOR, SC, width of the right testicle, volume of the right testicle, total testicular volume, and EDSP. From a productive–reproductive perspective, the Robin Hood Effect—through the use of rejected dairy cattle rations as the base diet for rams—and supplemented with nutraceuticals (WITH and LEPI), emerges as a viable alternative to improve not only the productive–reproductive performance of Black Belly rams, but also other productive and socioeconomic outcomes; the latter contributing to the strengthening of producer and family well-being.

Aim: To estimate the seroprevalence of bovine brucellosis (bBR) and identify risk factors associated with seropositivity to this disease. An additional aim was to evaluate heifer-related risk factors for abortion. Methods: A total of 3,848 Holstein heifers with a single lactation from a large commercial dairy herd in northern Mexico (25°N) participated in this study. Multiple regression models were employed to analyze risk factors for brucellosis seropositivity rate and to calculate odds ratios, quantifying the strength of the risks. Results: The seroprevalence of bBR was 30% (95% CI=29–32%) for lactating heifers (card test). Heifers weighing more than 680 kg at calving had half the risk of testing positive for bBR compared to those weighing less than 680 kg (22.7% vs. 36.1%). The risk of being seropositive for bBR increased in heifers with retained placenta compared to those without this reproductive disorder (OR=2.46; 47.5% vs. 26.3%). Heifers vaccinated with two doses of a commercial brucellosis vaccine had 2.2 times higher odds of being seropositive for bBR compared with those vaccinated only once (P<0.01). Seropositive heifers for bBR were 3.1 times more likely to abort than seronegative heifers (38.5% vs. 16.2%; P<0.01). Heifers with a body condition score (BCS) of 3.5 or higher at calving were less likely to abort than heifers with BCS<3.5. Conclusions: Brucellosis control programs should prioritize age at first calving, placenta retention, and the number of RB51 vaccinations administered to Holstein heifers.

A variety of statistical techniques were assessed for their usefulness for analysing the pattern of geographical and temporal changes in groundwater levels in order to diagnose the water supply in Meoqui, Chihuahua, which is situated in dry North-Central Mexico. These included Facebook Prophet, Lasso, generalized linear regularized models (GLMNET), autoregressive-integrated moving average (ARIMA), and a hybrid approach that merged Prophet and XGBoost. This was conducted on the assumption that the levels varied during the year and that it was possible to perform statistical analyses that derived a model explaining the changes and allowing for spatiotemporal prediction. The data set encompassed the period between 2020 and 2025 and was obtained from the Junta Municipal de Aguas y Saneamiento (JMAS) in Meoqui. The data set consisted of eight wells from which water was extracted for human consumption. The ARIMA model was identified as the optimal method for generating predictions on a monthly and annual basis. Furthermore, an inverse distance weighted (IDW) interpolation approach was utilised to conduct a spatial analysis. This enabled the visualisation of the predicted spatiotemporal changes in groundwater levels. The mean overall level was determined to be 26 m ± 16, with a minimum of 3 m and a lower level of 64 m. Models were estimated, comprising a general model and models specific to each well type. The best model for general level was Facebook Prophet (MAE 6.31, MAPE 16.28, MASE 1.23, SMAPE 16.79, RMSE 7.25, R-sq 0.29). The Sen’s slope of the historic level was found to be 0.38 (p < 0.001), thus indicating a decline in the groundwater level. The spatiotemporal analysis indicated a monthly decline in water levels from February to August, followed by an improvement in levels until November, which were then maintained until January. The lowest levels were observed in the area associated with Well 5. The findings of this study offer valuable insights into the spatiotemporal patterns of groundwater in the region, which could inform the development of sustainable groundwater management policies.

The objective of this research was to evaluate the effect of two doses of hCG (100 and 300 IU) administered at two different times after fixed-time artificial insemination (FTAI) on some response variables related to early fetal loss and total litter weight in goats during the reproductive transition period. Crossbred multiparous goats (n = 40) were subjected to an estrus induction protocol, subsequently inseminated, and randomly distributed into five experimental groups (n = 8): (1). G100-7, 100 IU hCG, 7 d post FTAI; (2). G100-14, 100 IU hCG, 14 days post FTAI; (3). G300-7, 300 IU hCG, 7 d post FTAI; (4). G300-14, 300 IU hCG, 14 days post FTAI; and (5). CONT, 0.5 mL of saline solution, 7 and 14 days post FTAI. The variables of corpus luteum area, embryonic implantation rate, embryonic efficiency index 1 and 2, conception rate, fertility rate, fecundity rate, fetal losses at days 30 and 45, total fetal losses, and the total weight of the litter favored G300-14. The use of hCG (300 IU) in the reproductive transition period is an effective reproductive strategy, reducing early fetal losses, improving embryonic efficiency, and increasing total litter weight, all of which are fundamental to the reproductive success of marginal goat production systems.

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 (n = 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; n = 16), received 5 mg selenium plus 350 IU vitamin E, and (2) the control group (CONT; n = 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 (p > 0.05) were observed between the groups for LW and BCS, the variables EI, OR, EMBRYO, and PREG rates were higher (p < 0.05) in the SeVE group than the CONT group. No differences (p > 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.

We evaluated the possible effect of maternal social rank (SR) concerning different morpho-physiological maternal indicators such as live weight (LWM, kg), body condition score (BCS, units), thoracic diameter (TD, cm), thoracic perimeter (TP, cm), and serum glucose content (GLU, mg dL⁻¹), upon the kid’s live weights (LWGK, kg) during the birth-to-weaning period. To define the SR [either high (HSR) or low (LSR)], a behavioral study was conducted on pregnant goats managed under semi-extensive conditions in northern arid Mexico (25° N; Alpine–Saanen–Nubian × Criollo; n = 15, 2–3 y/old) 30 days before the expected kidding date. The behavioral study was conducted during feeding time (i.e., 08:00, 13:00, and 17:00; 60 min test⁻¹, 180 min d⁻¹). The HSR goats showed higher values (p < 0.05) regarding prepartum, parturition, postpartum weights, and zoometric values. However, no differences (p > 0.05) between HSR and LSR goats occurred concerning the maternal serum glucose values, litter size, individual kid weights, or litter weights at weaning.

This review aims to emphasize the important role that goats and dairy goats play for many small-scale rural families worldwide, as well as to introduce a proposal for categorizing the main dairy goat production systems (DGPSs), using a multifactorial approach but emphasizing rainfall and nutritional supplementation level, as the focal categorization factors. The main DGPSs were divided into two metasystems based on available resources, each consisting of three production subsystems. In the first metasystem, the three subsystems have limited water, biotic, and economic resources, whose main economic rationality is based on reducing risk rather than maximizing outputs. In contrast, the three subsystems of the second metasystem usually have increased biotic, economic, and water resources, whose main emphasis involves maximizing product yield rather than reducing risk. The first metasystem involves DGPSs with a very limited or null nutritional supplementation: (a) subsistence, (b) extensive, and (c) agro-silvopastoral. The second metasystem includes those DGPSs with different levels of nutritional supplementation: (d) semi-extensive, (e) semi-intensive, and (f) intensive. There are numerous significant global initiatives focused on scientific collaboration and sharing information regarding nutrition, reproductive, and genetic technologies related to the safety and nutraceutical quality of goat milk and products while contextualized in different DGPSs. Hence, such scenarios should create additional opportunities for researchers, producers, policymakers, and development workers to come together and align interests and needs and exchange knowledge on effective goat farmer support strategies, environmental management, and consumer education. Undoubtedly, it is essential to reevaluate the DGPSs in the world since millions of producers and their families—most of them poor and marginalized—need this species, society needs their products, most of the worldwide arid and semi-arid lands need their recovery, and all of us should encourage the fulfillment of the sustainable development goals.

Considering a circular economy perspective, this study evaluates the possible effect of targeted short-term supplementation with Withania somnifera L. (WS; Ashwagandha) on ram’s seminal quality, socio-sexual behaviors, and blood constituents. Black Belly rams (n = 20) received a basal diet comprising feed-leftovers from dairy cows in the north-arid Mexico (i.e., Comarca Lagunera CL). The experimental units, with proven libido and fertility, were homogeneous in terms of age (3.41 ± 0.21 yr.), live weight (LW; 53.8 ± 3.3 kg), body condition (BC; 2.96 ± 0.01 units), initial sperm concentration (2387 ± 804 × 10⁶), and viability (23.9 ± 15.6%). Rams were randomly assigned during the transition reproductive period (i.e., May to Jun; 25° NL) to three treatment groups: non-supplemented control group (CONT; n = 6), low WS-supplemented (LWS; i.e., 100 mg kg LW⁻¹ d⁻¹ × 40 d; n = 7), and high-WS-supplemented (HWS; i.e., 200 mg kg LW⁻¹ d⁻¹ × 40 d; n = 7). The basal leftover diet was offered twice daily (0700 and 1600 h); the experimental period (EP) lasted 47 d. No differences (p > 0.05) among treatments occurred regarding LW and BCS at the onset of the EP. Whereas the greater scrotal circumference (SCRC, cm) arose in the LWS and CONT rams, an increased ejaculated volume (VOLEJA, mL) occurred in the WS-rams. A total of 5/9 (i.e., 55%) appetitive and 3/3 (i.e., 100%) consummatory sexual behaviors favored (p < 0.05) the WS-rams, particularly the HWS rams, towards the final EP. The same was true (p < 0.05) regarding the hemogram variables white blood cell count (×10⁹ cells L⁻¹), hemoglobin concentration (g dL⁻¹), and medium corpuscular volume (fL). This study, based on a rethink–reuse–reduce enquiry approach, enabled connectedness between two noteworthy animal systems in the CL: dairy cows and meat sheep schemes. Certainly, the use of dairy cow feed-leftovers aligned with the short-term supplementation with WS promoted enhanced testicular function, augmented seminal volume, and an increased sexual behavior in Black Belly rams in northern Mexico. Finally, while our research outcomes should enhance not only the resilience and sustainability of sheep production and the well-being of sheep-producers and their families, it may also embrace clinical translational applications.