Mayela Rodríguez-González

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.

The striped mullet (Mugil cephalus) and white mullet (Mugil curema) support artisanal fishing at the mouth of the Soto La Marina River, Gulf of Mexico, an area of great ecological value within the Laguna Madre and Rio Bravo Delta Protected Natural Area, the Terrestrial Priority Region RTP-83, and the Marine Priority Region RMP-44. Given the absence of historical catch and effort time series—a typical constraint of data-limited fisheries—a length-based frequency approach was used to estimate growth parameters, mortality rates, and the exploitation rate (E = F/Z). During 2018–2019, 1134 specimens of M. cephalus and 339 of M. curema were sampled. Due to sexual dimorphism in M. cephalus, analyses were performed separately for females, males, and combined sexes, while M. curema was analyzed with sexes combined. Growth (L∞, k) and mortality (Z, M, F) parameters for combined sexes were: M. cephalus (562 mm, 0.14 year⁻¹; 3.72, 0.21, 3.51 year⁻¹) and M. curema (329 mm, 0.15 year⁻¹; 1.46, 0.25, 1.21 year⁻¹). Exploitation rates (E) substantially exceeded Gulland (E = 0.5) and Patterson (E = 0.4) reference points: M. cephalus females (0.891), males (0.915), combined sexes (0.944), and M. curema (0.828). It is concluded that both stocks show strong evidence of growth overfishing, with exploitation rates well above established reference points, revealing a disconnect between the area’s conservation designations and the actual condition of the resource.

The striped mullet (Mugil cephalus) and white mullet (Mugil curema) support artisanal fishing at the mouth of the Soto La Marina River, Gulf of Mexico, an area of great ecological value within the Laguna Madre and Rio Bravo Delta Protected Natural Area, the Terrestrial Priority Region RTP-83, and the Marine Priority Region RMP-44. Given the absence of historical catch and effort time series—a typical constraint of data limited fisheries—a length based frequency approach was used to estimate growth parameters, mortality rates, and the exploitation rate (E = F/Z). During 2018–2019, 1,134 specimens of M. cephalus and 339 of M. curema were sampled. Due to sexual dimorphism in M. cephalus, analyses were performed separately for females, males, and combined sexes, while M. curema was analyzed with sexes combined. Growth (L∞, k) and mortality (Z, M, F) parameters for combined sexes were: M. cephalus (562 mm, 0.14 year⁻¹; 3.72, 0.21, 3.51 year⁻¹); M. curema (329 mm, 0.15 year⁻¹; 1.46, 0.25, 1.21 year⁻¹). Exploitation rates (E) substantially exceeded Gulland (E = 0.5) and Patterson (E = 0.4) reference points: M. cephalus females (0.891), males (0.915), combined sexes (0.944); M. curema (0.828). It is concluded that both stocks are experiencing severe overexploitation, revealing a disconnect between the area's conservation designations and the actual condition of the resource.

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.

Introducción: Los estudios de expresión génica requieren protocolos de extracción que permitan la obtención de ARN de alta calidad, especialmente cuando se trabaja con tejidos ricos en polisacáridos, lípidos y polifenoles como el tejido embrionario de nuez pecanera (Carya illinoinensis [Wangenh.] K. Koch).Objetivo: Evaluar la eficiencia de ocho métodos de extracción de ARN total a partir de tejido embrionario de nuez pecanera. Materiales y métodos: Se evaluaron ocho protocolos de extracción de ARN total basados en el reactivo TRI Reagent®, buffer CTAB (bromuro de hexadeciltrimetilamonio) y un kit comercial. El rendimiento y calidad de ARN total se determinaron por espectrofotometría (UV/visible). La viabilidad e integridad del ARN se analizó mediante RT-PCR utilizando actina como gen de referencia. Resultados y discusión: Los protocolos de extracción basados en el reactivo TRI Reagent® permitieron la obtención de concentraciones altas de ARN total, pero con grado elevado de contaminación. Mediante el uso del kit comercial fue posible la extracción de ARN total, pero sin la pureza óptima esperada. Finalmente, los protocolos basados en el buffer CTAB consiguieron rendimientos de ARN total de calidad óptima. Conclusiones: La calidad del ARN total varía de acuerdo con la eficiencia del método utilizado. El protocolo CTAB 4 representa una alternativa eficaz para el aislamiento de ARN de tejidos embrionarios de C. illinoinensis.

Introducción: La viviparidad en nogal pecanero (Carya illinoinensis [Wangenh.] K. Koch) ha incrementado considerablemente. Este fenómeno genético-ambiental puede ser controlado con el manejo de humedad del suelo y otras variables de calidad. Objetivo: Determinar el efecto del contenido de humedad del suelo sobre el rendimiento, tamaño de nuez, porcentaje de almendra y nuez germinada en el árbol. Materiales y métodos: Árboles de nogal de 40 años fueron regados por 40 emisores con gasto de 3.2 L∙h-1. A partir de la etapa fenológica de endurecimiento de cáscara, el tiempo de riego fue de 4, 6 y 8 h, correspondientes a niveles de humedad de 0.257, 0.327 y 0.380 m3 de agua por m3 de suelo, a profundidad de 40 a 80 cm. El rendimiento por árbol, porcentaje de nuez germinada, tamaño de fruto y porcentaje de almendra se evaluaron durante los ciclos productivos 2016 y 2017. Resultados y discusión: Durante los dos ciclos de producción, cuando el nivel de humedad en el suelo aumentó de 0.257 a 0.380 m3 ∙m-3, la producción de nuez por árbol, la longitud y diámetro del fruto, y el porcentaje de almendra incrementaron en promedio 23.8 %, 25.3 y 10 %, y 1.8 %, respectivamente; sin embargo, la viviparidad incrementó 11.2 %, lo cual se vio reflejado en la disminución del porcentaje de nuez comercial. Los tratamientos 0.327 y 0.380 m3 ∙m-3 tuvieron un efecto similar (P > 0.05) en dichas variables. Conclusiones: El menor nivel de humedad (0.257 m3 ∙m-3), a partir del llenado de almendra, disminuyó la viviparidad y aumentó el porcentaje de nuez comercial.