Pedro Antonio Robles-Trillo

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.

Attempting to detect and improve the management of Ketosis, the objective of this study was to determine and confirm the relationship between hours of activity, rumination time, conductivity, and milk production with the presence of ketosis in cows during the transition period in dairy cows in the Comarca Lagunera region, the heart of the dairy cattle production in Mexico. Data were collected in a large scale dairy cattle study. High-precision electronic collar sensors, high-precision electronic scales, and online electronic weighing sensors were employed to determine activity and ruminating time, milk electrical conductivity, and milk yield, respectively. All data were collected and integrated using an electronic peripheral management and control software. Using urinary ketone bodies measured by qualitative strips as the biomarker for ketosis, 10.50% of the cows were found to be positive for ketosis, while the remaining 89.50% were negative. The mean and standard error for activity time (AT), ruminating time (RT), milk electrical conductivity (CE) and milk yield (MY) in normal (N) vs ketotic (P) cows were: AT N 61.38, ± 0.39, AT P 39.08 ± 0.49; RT N 530.85 ± 2.94, RT P 295.24 ± 10.69; CE N 5.68 ± 0.03, CE P 9.13 ± 0.11; and MY N 38.87 ± 0.29, MY P 20.34 ± 0.54. Exploratory Factor Analysis (EFA) was conducted for the purpose of uncovering the underlying structure of the data by identifying latent constructs that influence the observed variables. The EFA estimated two factors which explained 62% of the variation observed. The Factor 1 (MR1) comprising the variables MY and EC, and Factor 2 (MR2), which consists the variables AT and RT. High-precision measurement sensors along multivariable analyses could facilitate the establishment of a correlation between ketosis and variables associated with the physiology, well-being, and productivity of bovines in the transition period. It further open the possibility of early detection of metabolic diseases such as ketosis.

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.

Background: The present study was designed to evaluate the correlation of limb torsion and distal asymmetry (LTDA) with respect to zoometric, productive and reproductive variables in Holstein cows. Methods: A total of 120 cows diagnosed with LTDA in a previous experiment (60 positive and 60 negative) with one or more lactations were randomly selected for measurement. The height at withers (cm), neck length (cm) and head length (cm) of all cows were measured. Records were obtained for the year of the study regarding lactation order, days in milk, mean of milk production in 24 h (kg), number of inseminations per conception, days open and body condition (scale 1-5). The association between LTDA and zoometric measures along with productive and reproductive variables was evaluated by multiple logistic regression. Result: A statistically significant correlation (p less than 0.05) was observed between the zoometric variable’s height at withers and neck length, while no association was found between LTDA and head length (p greater than 0.05). The study revealed no effect of LTDA on productive variables (p = 0.38), however an effect of LTDA on reproductive variables was significant (p = 0.01), primarily on body condition. However, the findings indicate that body condition exerts an influence on the occurrence of LTDA in Holstein cows stabled under intensive systems in other words LTDA can impact certain variables, particularly reproductive ones.

The objective of this study was to estimate the seroprevalence of Ehrlichia canis in clinically suspect dogs in the Laguna Region of Coahuila, Mexico, and to analyse its association with several clinical, haematological, and social variables. The present study focuses on the veterinary care provided to a total of 249 dogs during the period from August 2023 to November 2024. The implementation of an immunochromatographic test was undertaken for the purpose of antibody detection. The observed seroprevalence was 63.9% (n = 156). Firstly, statistically significant associations were identified with clinical haemorrhagic signs (77.33%; OR = 5.03; p < 0.001), anaemia (81.25%; OR = 4.17; p < 0.001), and thrombocytopenia (96.26%; OR = 43.24; p < 0.001). Secondly, rural dogs exhibited a higher prevalence (70.54%) compared to urban dogs (54.17%), which was found to be statistically significant (p < 0.01). Multivariate analysis and logistic regression identified thrombocytopenia as the most robust predictor. The findings emphasise the substantial circulation of Ehrlichia canis in the region, thereby reinforcing the clinical significance of haemorrhagic manifestations and haematological parameters as diagnostic tools in low-resource settings. The implementation of epidemiological surveillance, vector control, and community education programmes is recommended in order to reduce the impact of this disease on animal and public health.

Colostrum is the first mammary secretion and is the only way in which calves can obtain passive immunity. This study aimed to correlate the quality of colostrum from high-yielding dairy cows using either a colostrometer or Brix digital refractometry (°Bx). Samples (N=340) of colostrum were taken from cows and analyzed with a colostrometer and Brix refractometry. A linear regression was performed, the coefficient of determination (R2) was calculated. All statistical analyzes were done with the SPSS 25.0 statistical package. Means with colostrometer were 87.94±110, while with Brix refractometer they were 26.19±18, with R2 0.706 and a P<0.0001. In conclusion, the refractometer and the colostrometer are effective methods to determine immunoglobulins. Brix refractometer had an acceptable correlation, which could be a useful tool for verifying the colostrum’s quality next to the cow. http://dx.doi.org/10.21929/abavet2024.5 e2021-82 https://www.youtube.com/watch?v=Lw5YXZU0af8 El calostro es la primera secreción mamaria y es la única forma en la cual las becerras adquieren inmunidad pasiva. El objetivo de este estudio es determinar la correlación de la calidad del calostro de vacas lecheras de alta producción medido con calostrómetro y refractometría digital de grados Brix (°Bx). Se tomaron 340 muestras de calostro del mismo número de vacas y fueron analizadas mediante el calostrómetro y refractometría de °Bx. Se realizó una regresión lineal simple y se determinó el coeficiente de determinación (R²). Todo a través del paquete estadístico SPSS 25.0. La media de con calostrómetro fue de 87.94±110, mientras con refractometría Brix fueron de 26.19±18, con una R2 0.706 con un valor de P<0.0001. En conclusión, las lecturas de refractometría y el calostrómetro, son métodos efectivos en determinar las inmunoglobulinas. El refractómetro Brix tuvo una correlación aceptable, lo cual puede ser una herramienta fácil de verificación de calidad de calostro al pie de la vaca. http://dx.doi.org/10.21929/abavet2024.5 e2021-82 https://www.youtube.com/watch?v=Lw5YXZU0af8 http://dx.doi.org/10.21929/abavet2024.5 e2021-82 https://www.youtube.com/watch?v=Lw5YXZU0af8

The possible effect of heat stress (HS), measured with the temperature–humidity index (THI) across seasons of the year (SY) upon milk production (MP), feed-to-milk efficiency (FME), and cow comfort (CC) was assessed in Holstein–Friesian cows in northern-arid Mexico. Data from 2467 cows (2146 milking and 321 dry) were recorded across SY [spring (SP), summer (SM), autumn (AT), and winter (WN)] between 2016 and 2019 in an intensive dairy farm located in the Comarca Lagunera (25° NL) with large fluctuations regarding ambient temperature and solar radiation. The THI was stratified into four classes: non-HS, p < 0.05) as HS increased; the largest values (i.e., 77,886 L and 35.9 L) occurred at lower THIs (i.e., p < 0.05) occurred from a THI of 68–71 onwards. Furthermore, the LT declined as the THI augmented, from 10.6 h at p < 0.05) also arose across seasons; TotMP, cowMP, DMI, FCE, and ECM revealed their largest (p < 0.05) values in WN and SP, halfway ones in AT, with the lowermost figures in SM. In the same way, cow comfort differed (p < 0.05) among seasons, with diverse lying times (h); WT, 10.5; AT, 10.20; SP, 9.3 h; and 8.8 in SM. Finally, the potential economic burden that HS caused at the producer (USD 233.2 million) and industry-market levels (USD 311.1 M), as well as its impact upon nutrient and alimentary security at the society level (i.e., 311 M milk liters and 195,415.82 Gcal), were also quantified.

This study characterized the environmental–climatic trends occurring in the largest dairy cattle intensive production cluster under arid land conditions in northern Mexico. The study was based on the Temperature Humidity Index (THI); it aimed to identify the number of days with THI values ≥68 as a bio-marker of heat stress (HS) and evaluate the possible HS effect upon the milk production of dairy cows. Climate data were obtained every 10 min in five farms across years (i.e., 2015–2020). THI was divided into four HS subclasses, 68–71, 72–76, 77–79, and ≥80, according to the circadian HS occurrence (i.e., 1, 4, 8, 12, 16, 20, 24 h), and analyzed across seasons–years. Thus, a total of 1,475,319 THI across different time-scale subclasses was analyzed. The observed results supported our working hypothesis in that yearling-average periods with more than 300 d, HS was confirmed. A yearly average of 31.2 d with THI ≥ 80 with similar (p > 0.05) trends across dairy farms and a slight annual variation (p < 0.05) were also witnessed. Moreover, the highest days with THI levels ≥68 occurred in summer and autumn (p < 0.05), while the in the subclasses 68–71, 72–76, and 77–79, THI occurred in any hour-scale subclass (i.e., 1, 4, 8, and 12 h). Furthermore, a trend to observe THI-HS increases either among years or within an hour-scale basis were also observed. On average, HS engendered a reduction of up to 11.8% in milk production. These research outcomes highlight the need to identify and quantify the negative impacts that HS may generate at a productive and reproductive level in order to delineate mitigation strategies that may lessen the environmental impact upon the dairy cattle industry.

Two experiments were carried out to determinate the effects of peNDF and forage level on DMI, ruminal pH and milk production and composition in goats. In experiment 1, 4 non lactating goats were used; and in experiment 2, 8 goats in early lactation were used, they were assigned to a 4x4 latin square with 2x2 factorial design. The experimental diets were offered ad libitum and consisted of forages with long (4.04 cm) and short (3.43 cm) particles sizes in a 60:40 or 35:65 forage:concentrate ratio. No differences were observed in dry matter intake in goats fed with long or short forages particle size (P>0.05). Ruminal pH were affected by F:C ratio, the lower pH was observed in goats fed 35:65. No effect was observed on milk production. Milk fat was affected only for the F:C ratio and was higher in the 60:40 diets. This study shows that the concentrate ratio in the diet is more important to affect ruminal pH and milk fat than the forage particle size.