Understanding the genetic structure of Native American populations is important to clarify their diversity, demographic history, and to identify genetic factors relevant for biomedical traits. Here, we show a demographic history reconstruction from 12 Native American whole genomes belonging to six distinct ethnic groups representing the three main described genetic clusters of Mexico (Northern, Southern, and Maya). Effective population size estimates of all Native American groups remained below 2,000 individuals for up to 10,000 years ago. The proportion of missense variants predicted as damaging is higher for undescribed (~ 30%) than for previously reported variants (~ 15%). Several variants previously associated with biological traits are highly frequent in the Native American genomes. These findings suggest that the demographic and adaptive processes that occurred in these groups shaped their genetic architecture and could have implications in biological processes of the Native Americans and Mestizos of today.

Water buffaloes have morphological and behavioral characteristics for efficient thermoregulation. However, their health, welfare, and productive performance can be affected by GW. The objective of this review was to analyze the adverse effects of GW on the productive behavior and health of water buffaloes. The physiological, morphological, and behavioral characteristics of the species were discussed to understand the impact of climate change and extreme meteorological events on buffaloes’ thermoregulation. In addition, management strategies in buffalo farms, as well as the use of infrared thermography as a method to recognize heat stress in water buffaloes, were addressed. We concluded that heat stress causes a change in energy mobilization to restore animal homeostasis. Preventing hyperthermia limits the physiological, endocrine, and behavioral changes so that they return to thermoneutrality. The use of fans, sprinklers, foggers, and natural sources of water are appropriate additions to current buffalo facilities, and infrared thermography could be used to monitor the thermal states of water buffaloes.

The overall goal of this study was to estimate the prevalence of gastrointestinal (GI) parasites in dogs in the city of Villahermosa in Tabasco, Mexico. The study population consisted of 302 owned dogs that had limited access to public areas. A fecal sample was collected from each animal and examined for GI parasites by conventional macroscopic analysis and centrifugal flotation. Fecal samples from 80 (26.5%) dogs contained GI parasites. Of these, 58 (19.2%) were positive for helminths and 22 (7.3%) were positive for protozoan parasites. At least seven parasitic species were identified. The most common parasite was Ancylostoma caninum which was detected in 48 (15.9%) dogs. Other parasites detected on multiple occasions were Cystoisospora spp. (n = 19), Toxocara canis (n = 7) and Giardia spp. (n = 3). Three additional parasites, Dipylidium caninum, Trichuris vulpis and Uncinaria spp., were each detected in a single dog. No mixed parasitic infections were identified. In summary, we report a moderately high prevalence of GI parasites in owned dogs in Villahermosa, Tabasco. Several parasitic species identified in this study are recognized zoonotic pathogens which illustrates the important need to routinely monitor and treat dogs that live in close proximity to humans for parasitic infections.

The aim of this study was to develop and evaluate equations to predict body weight (BW) using heart girth (HG) in Pelibuey ewes. For model develop a data set composed by 366, 3-year-old, non-pregnant and non-lactating ewes; with a mean BW of 45.7±9.16 kg and HG of 87.55± 7.93 cm was used. A linear equation was fitted: BW= -47.97 (±2.01*) + 1.07 (±0.02**)×HG (R2 = 0.86, RMSE = 3.46, , y n = 366). A second data set composed by 67 animals, with similar characteristics (BW of 38.25± 8.62 kg and HG of 80.37± 7.03 cm) was used to evaluate the developed equations. For the evaluation, the relationship between observed and predicted values of BW by linear regression, the mean squared error of prediction (MSEP) and root MSEP (RMSEP), and concordance correlation coefficient analysis were used. The proposed equation was highly precise (r2 =0.913) and accurate (Cb=0.996) with a reproducibility index of 0.95. The MEF have indicates a higher efficiency of prediction with higher proportion of the total variance of the observed values been explained by the predicted data (0.91). The partition of the MSEP have indicated a very small mean bias (0.082). The systematic bias have shown that only 1.93% of the error of prediction was associated with the slope and most of the error was explained by the random component indicating small biases with the predictions. The proposed equation accurately and precisely estimated the BW of Pelibuey ewe using HG and therefore is recommended to be used.

The study aimed to evaluate the relationship between udder measurements and milk yield (MY) in dairy Pelibuey ewes. Udder measurements were taken twice a week for eight weeks before (initial) and after (final) milking, including udder depth (UD), udder circumference (UC), udder width (UW), teat length (TL) and teat diameter (TD) in 38 multiparous ewes. Additionally, udder volume (UV) and the difference (VDF) between initial UV (UVi) and final (UVf) was calculated as VDF = UVi − UVf. The MY varied from 0.10 kg/d to 1.04 kg/d, with a mean of 0.39 kg/d, ± 0.18 kg/d. Initial UC (UCi) ranged from 25.80 cm to 53.30 cm, and VDF varied from 1 cm³ to 2418 cm³. The TL and TD were not correlated with MY (p > 0.05), while UCi, UVi and VDF were positively correlated with MY (p < 0.0001; r = from 0.66 to 0.74). For the prediction of MY, the obtained equations had an r² ranging from 0.54 to 0.63. The UCi, UDf, UWi and UWf were included in these models (p < 0.05). It is concluded that there was an acceptable correlation (r = 0.60) between the measurements of the udder, the volume of the udder and the daily milk yield in Pelibuey sheep. When direct measurements of milk production cannot be performed in practice, the measurement of udders and their volume could be a viable alternative to estimate milk yield production as an indirect method.