The Region Lagunera, a region in northeast Mexico, is undergoing significant problems with the quality of its groundwater, which exceeds the permissible limits of contaminants and/or heavy metals stipulated in Mexican legislation. The present study evaluated chronic toxicity in male goats exposed to arsenic via one ex situ Group 1 (n = 5) and one in situ female goats Group 3 (n = 10). The treatment in Group 1 was carried out in the La Laguna experimental field of the Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP), located in Matamoros, Coahuila, Mexico. Sodium arsenite (2 mg/kg) was orally administered for 84 days to five male Creole goats, aged between four and five years old and weighing between 60 and 70 kg, in order to determine its effect on urine toxicity, libido, and physiological condition, an untreated group (n = 5) was included (Group 2). The experiment in group 3 was conducted on ten female Creole goats, aged between four and six years old and weighing between 40 and 49 kg, in both the contaminated sampling area in the rural community of El Venado and the control sampling area in the rural community of Nuevo Reynosa (Group 4 (n = 5)), in which the arsenic levels were measured in the urine of the exposed goats, as was their physiological condition. Significant differences (p < 0.01) between the groups were found in both the arsenic concentration in the urine and the physiological condition observed in both experimental groups.

The objective was to evaluate the effects of two (2×) vs three (3×) times per day milking on milk production and milk composition in dairy cows. Fourteen scientific papers, containing production data from 16 trials, where dairy cows were milked 2× or 3×, were analysed using meta-analysis with fixed and random-effects with the R statistical program. The degree of heterogeneity and publication bias were measured with the I2 statistic and Begg’s test, respectively. In addition, the meta-regression analysis explored other sources of heterogeneity for the response. The estimated effect size of 2× and 3× milkings was calculated for dry matter intake (DMI), milk production, and milk composition. Dry matter intake, milk production, and milk fat and protein yields showed substantial heterogeneity (I2>50%). Whereas milk fat-percentage had moderate heterogeneity (I2.05). Cows milked 2× produced less milk (2.23 kg/d), less milk fat (0.06kg/d), and less milk protein (0.05 kg/d). In contrast, the fat percentage was lower (0.07 units) in 3×, compared with 2× milking frequency. There was no effect of milking frequency on DMI and milk protein percentage. In conclusion, milk production and milk fat and protein yields improves as milking frequency increase from 2× to 3× daily, without affecting DMI. The implementation of 3× milking frequency must consider dairy cow management, labor, and milking parlour infrastructure, particular to each dairy farm.

Dairy products provide essential nutrients when consumed and they also create rural employment. A small dairy can help a family maintain their livelihood. The objective of this study was to evaluate the microbiological quality of raw goat milk obtained during the milking-storage process using Good Hygiene Practices. The study was carried in northern Mexico, which is characterized by a desert climate. The experiment was carried in four herds, six samplings per herd with a total of 302 goats. Samples of milk extracted directly from the udder, milk extracted from the milking bucket and milk extracted from the storage bucket were analyzed. In addition, samples were taken from the milker’s hands. The data were analyzed using ANOVA and the statistical difference with the Tuky test (p < 0.05). A significant difference (p < 0.05) was observed in Total Coliforms (TC) for milker’s hands, milk extracted directly from the udder, milk extracted from the milking vat and milk extracted from the storage vat. However, at the time when the Good Hygiene Milking Practices GHPM treatment was stopped (June-July), higher CFU/mL of TC were observed in all stages of the milking-storage process. The pathogenic microorganisms identified were Escherichia coli, Salmonella spp. and Shigella spp. raw goat milk can be easily contaminated during the milking-storage process, since the common practice is to milk in the pen among other animals, manure and soil. To improve quality and sustainability parameters, it is necessary to have an exclusive space for milking as well as the implementation of GHPM. Better business alliances and better ethics between suppliers and industrial producers are also necessary.

The aim of this study was to assess lactation traits, lactation curve shape and curve parameters in Katahdin sheep under a grazing-based feeding system. A total of 27 second-parity Katahdin ewes were evaluated. The animals were kept on a pasture composed of cool-season grasses and legumes. The variables recorded included litter size, lamb sex, daily milk yield per ewe, total milk yield per lactation, lactation length, prolificacy, and gestation duration. Statistical analysis was conducted using the GLM procedure. Ewes with twins and female lambs produced more milk per day (58 and 34%), respectively, and per lactation (23%) (p 0.05). The lactation length and milk yield did not differ (p 0.05) when considering litter size and lamb sex. Parameters “a” and “b” showed the highest standard error values with lower estimator values, while parameter "c" showed lower estimator and standard error values. It is concluded that Katahdin ewes under grazing conditions achieve adequate milk production, with positive effects associated with litter size and lamb sex. Additionally, the lactation curve displayed the characteristic shape, with peak production occurring at 3 and 4 weeks postpartum.