Purpose The purpose of this study was to assess clinical characteristics and risk factors for mortality of patients with coronavirus disease 2019 (COVID-19) from Mexico, given that it currently is in active community transmission. Methods Multivariate logistic regression model and Kaplan–Meier survival curves were fitted to study odds of death of characteristics and comorbidities in patients with COVID-19 in Mexico. Results Age, sex, and the most frequent comorbidities diabetes, obesity, and hypertension were significantly associated to the risk of death by COVID-19 ( P < .0001). Smoking habit was not identified as a risk factor for death. Less-frequent comorbidities such as chronic obstructive pulmonary disease, chronic kidney disease, and patients with immunosuppressed conditions also showed a significant risk for death ( P < .0001). Hospitalized patients and those with pneumonia had serious risks for mortality ( P < .0001), and more attention to specific conditions might be considered during clinical admission. Conclusions A more vulnerable positive patient is depicted by a male patient, older than 41 years, which increases their risk with more prevalent comorbidities such as diabetes, hypertension, and obesity. Some implications on outcomes are discussed.

Cattle temperament is a complex trait, and molecular studies aimed at defining this trait are scarce. We used an interaction networks approach to identify new genes (interacting genes) and to estimate their effects and those of 19 dopamine- and serotonin-related genes on the temperament traits of Charolais cattle. The genes proopiomelanocortin (POMC), neuropeptide Y (NPY), solute carrier family 18, member 2 (SLC18A2) and FBJ murine osteosarcoma viral oncogene homologue (FOSFBJ) were identified as new candidates. Their potential to be associated with temperament was estimated according to their reported biological activities, which included interactions with neural activity, receptor function, targeting or synthesis of neurotransmitters and association with behaviour. Pen score (PS) and exit velocity (EV) measures were determined from 412 Charolais cows to calculate their temperament score (TS). Based on the TS, calm (n = 55; TS, 1.09 ± 0.33) and temperamental (n = 58; TS, 2.27 ± 0.639) cows were selected and genotyped using a 248 single-nucleotide variation (SNV) panel. Of the 248 variations in the panel, only 151 were confirmed to be polymorphic (single-nucleotide polymorphisms; SNPs) in the tested population. Single-marker association analyses between genotypes and temperament measures (EV, PS and/or TS) indicated significant associations of six SNPs from four candidate genes. The markers rs109576799 and rs43696138, located in the DRD3 and HTR2A genes, respectively, were significantly associated with both EV and TS traits. Four markers, rs110365063 and rs137756569 from the POMC gene and rs110365063 and rs135155082 located in SLC18A2 and DRD2, respectively, were associated with PS. The variant rs110365063 located in bovine SLC18A2 causes a change in the amino acid sequence from Ala to Thr. Further studies are needed to confirm the association of genetic profile with cattle temperament; however, our study represents important progress in understanding the regulation of cattle temperament by different genes with divergent functions.

The objective of this study was to perform a genomewide association study (GWAS) for growth traits in Charolais beef cattle and to identify SNP markers and genes associated with these traits. Our study included 855 animals genotyped using 76,883 SNP from the GeneSeek Genomic Profiler Bovine HD panel. The examined phenotypic data included birth, weaning, and yearling weights as well as pre- and postweaning ADG. After quality control, 68,337 SNP and 823 animals were retained in the analysis. The association analysis was performed using the principal components method via the egscore function of the GenABEL version 1.8-0 package in the R environment. Eighteen SNP located in 13 BTA were associated with growth traits ( < 5 × 10). The most important genes in these genomic regions were (), (), (), (), and ( [angiotensinase C]), due to their relationships with perinatal and postnatal survival, bone growth, cell adhesion, regulation of adipogenesis, and appetite. In conclusion, this study is the first to describe a GWAS conducted in beef cattle in Mexico and represents a basis for further and future research. This study detected new QTL associated with growth traits and identified 5 positional and functional candidate genes that are potentially involved in variations of the analyzed traits. Future analyses of these regions could help to identify useful markers for marker-assisted selection and will contribute to the knowledge of the genetic basis of growth in cattle and be a foundation for genomic predictions in Mexican Charolais cattle.

Pre-weaning is an important stage in sheep production systems focussed on meat production. In this stage, maternal ability has a key role in lamb development and productivity. The objective of this study was to evaluate the effect of breed and litter size at birth on the ewe and lamb pre-weaning performance under tropical conditions. The lambs and their dams were managed in a feedlot system during 56 days in individual pens. Milk production was estimated weekly by the weight-suck-weight method. Daily milk production (DMY), total milk production (TMY), body weight change during the lactation (BWC), litter weaning weight (LWW) and ewe weaning efficiency (EE) were estimated as ewe pre-weaning performance; and, birth weight, weaning weight at 56 days and average daily gain were estimated as lamb pre-weaning performance. Katahdin ewes produced more TMY than Pelibuey ewes (p < .001) but ewes from both breeds had similar overall LWW and EE. Pelibuey ewes had a more negative BWC than Kathadin ewes (p < .05). Katahdin lambs had greater birth weights (p < .05), but similar preweaning growth and live weight at weaning compared with Pelibuey lambs. Litter size effect was significant for all the traits except for BWC in both breeds. Compared to Katahdin twin-born lambs, Pelibuey twin-born lambs were lighter at birth but of similar weight at weaning. Litter size is an important factor conditioning pre-weaning performance of ewes and lambs of Pelibuey and Katahdin breeds under humid tropical conditions. HIGHLIGHTS Some indicators of ewe and lamb pre-weaning performance of Pelibuey and Katahdin hair sheep under tropical conditions were evaluated. The Katahdin ewes produced more milk than Pelibuey ewes, yet ewes from both breeds had similar litter weaning weight. Litter size is an important factor determining pre-weaning performance in Pelibuey and Katahdin hair sheep breeds under humid tropical conditions. ARTICLE HISTORY

ABSTRACT. We examined allele and genotype frequencies for the molecular markers CAPN1 316, CAPN1 4751 and TG5, and determined whether they are associated with beef quality traits in Mexican cattle. One hundred and twenty-four longissimus dorsi muscle samples were collected from cattle from north, central and southern Mexico. CAPN1 316 and CAPN1 4751 frequencies were determined using the allelic discrimination assay and the TG5 marker was typed by PCR-RFLP. Meat quality traits included intramuscular fat content (IMF) and tenderness determined by Warner-Bratzler shear force (WBSF) at 24 h postmortem. The association test was made using a mixed model, including genotypes, genetic group, and sampling location as fixed effects. Least squares means and significant interactions were compared using least significant differences based on the mixed procedure. CAPN1 316 CC was found at a low frequency (0.03) and has been reported as a favorable genotype associated with tenderness meat. Genotype frequencies for CAPN1 4751 were similar in favorable (CC) and unfavorable (TT) genotypes (0.26 and 0.28, respectively). The TG5 CC genotype had a frequency of 0.73, while the TT genotype frequency was 0.01. The means for WBSF and IMF were 4.08 ± 1.35 kg and 5.23 ± 2.14%, respectively. Sampling site and the CAPN1 316 genotypes significantly affected WBSF (P < 0.05). Samples collected from Hermosillo, Sonora, had the lowest WBSF (P < 0.05), while those collected in Veracruz were toughest (WBSF = 5.267 kg). The effect of GG and TG5 genotypes on IMF was significant (P < 0.05). CAPN1 316 and TG5 markers were found to be significantly associated with beef quality traits and thus will be useful for Mexican beef characterization.