Toxicity in Goats Exposed to Arsenic in the Region Lagunera, Northern Mexico.

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.

Physicochemical characterization of goat milk produced in the Comarca Lagunera, Mexico.

The purpose of this study was to determine goat milk physicochemical parameters during the feed scarcity season. An evaluation was made for 398 milk samples from 80 multiparous goats belonging to three different production systems: (S1) mechanized milking grazing pasture and harvested residue (alfalfa) and grain supplemented; (S2) system grazing native pasture; and (S3) system grazing native pasture and grain supplemented. The general averages were: fat (FT) 4.0 ± 0.20%, protein (PR) 3.3 ± 0.05%, lactose (LC) 4.9 ± 0.09%, nonfat solids (NFS) 8.9 ± 0.13%, total solids (TS) 14.5 ± 0.20%, temperature (TM) 24.6 ± 1.06°C, and acidity (pH) 6.7 ± 0.049. Most of the physicochemical components of milk were affected (p < 0.0001) by the production system × month interaction and production system × group × month interaction. The FT content was higher (p < 0.05) in S2 (4.56 ± 0.18) than in S1 (3.64 ± 0.20) and S3 (3.50 ± 0.20). LC differed (p < 0.05) in S2 (5.07 ± 0.08) than in S1 (4.77 ± 0.09) and S3 (4.70 ± 0.09). No differences were observed for the rest of the variables (p < 0.05) among the production systems. The study unveiled a higher content of FT, LC, NFS, PR, and TS for S2 than for S1 and S3. This higher content may be explained because S2 only grazed on herbs and shrubs, in contrast to S1 and S3 which were additionally supplemented with grain concentrates.

Long-term betacarotene-supplementation enhances serum insulin concentrations without effect on the onset of puberty in the female goat.

The effect of betacarotene (BC) supplementation on the onset of puberty and serum insulin levels in goats was evaluated in the study. In June, prepuberal goats (n=17; 3 months old; 7/8 Saanen-Alpine; 26° NL) were randomly assigned to one of two groups: 1/ betacarotene group supplemented daily with 50 mg of BC (n=9; live weight [LW]: 17.3±1.0 kg; body condition score [BCS]: 3.34±0.12) or 2/ control group (CONT; n=8; LW:16.1±1.0 kg; BCS=3.17±0.12). From June to November, an intermittent blood sampling was performed twice per week in both groups to evaluate serum progesterone (P(4)), while monthly samples were intended for insulin (INS) determination. Initial mean LW (16.7±1.0 kg) and BCS (3.31±0.12) were similar (p>0.05) in both groups. Mean serum insulin (1.37 vs. 1.18±0.09 ng/ml), age of puberty (215.7 vs. 226.5±6.6 days) and the percentage of goats reaching puberty (44.4 vs. 25.0±17.0%) did not differ (p>0.05) between BC and CONT group, respectively. However, increase in serum insulin during the second half of the experiment was observed in BC group (p<0.05) which was positively correlated with LW (r=0.95; p<0.05). In addition, as LW (r=-0.89) and serum insulin (r=-0.76) levels increased, the natural photoperiod decreased, revealing negative correlations (p<0.05) between the respective variables. In this study, BC supplementation did not promote precocious puberty and did not affect the percentage of goats reaching activation of the hypothalamic-hypophyseal-gonadal axis during the establishment of puberty. Nonetheless, BC supplementation positively affected the release pattern of insulin suggesting a potential role of BC as pancreas-activating molecule.