El objetivo del presente estudio fue evaluar el efecto de la aplicación de meloxicam en cerdas de primer parto sobre el número de lechones nacidos vivos, y el número y el peso de los lechones al destete en una granja comercial en el trópico subhúmedo de México. Se usaron 540 cerdas (270 cerdas por tratamiento). El grupo tratado recibió meloxicam (Metacam® 20 mg/ml, 0.4 mg/kg de peso corporal. IM) durante el parto y el grupo control no fue tratado. No se encontraron diferencias significativas para las variables en estudio entre los dos grupos experimentales.

The aim of this study was to evaluate the effect of the application of meloxicam in first-parity sows on the number of piglets born alive, and the number and weight of piglets at weaning in a commercial farm in the sub-humid tropics of Mexico. For this, 540 sows (270 sows per treatment) were used. The treated group received meloxicam (Metacam® 20 mg/ml, 0.4 mg/kg of body weight. IM) during farrowing and the control group was not treated. There were no significant differences for the variables under study between the two experimental groups.

The aim of the present study was to evaluate the effect of weaning weight on the productive performance of fattening lambs in raised pens. Data from 932 lambs from one farm over a period of two years were analyzed. The statistical model included the fixed effects of weaning weight (<11, 12-14, 15-17, >18 kg), year (2012 and 2013), season of the year (rainy, dry and northern winds) and simple significant interactions of year × season and the residual error, NID (0, σ2e) on average daily weight gain (GDP, g/d), final weight (PF, kg) and fattening period (PE, days). Weaning weight affected all the response variables evaluated (p<0.05). The weaned lambs between 12-14, 15-17 and >18 kg had a similar GDP, and in turn obtained a higher GDP than the weaned lambs with lower weight (<11 kg; p<0.05). The PF was similar for lambs weaned at 15-17 and >18 kg but higher than that...

This study aimed to determine the effects of space allowed (SA), season of the year (SY) and year (YR), and simple interactions on productive traits of hair lambs housed in raised slatted floor cage (RFC). Data from initial weight (IW, kg), final weight (FW, kg), adjusted weight at 90 days (FWA, kg), daily weight gain (DWG, g) and finalization period (FP) of 982 lambs were evaluated. Data for FW, FWA and DWG was analysed using general linear models and FP using survival analysis. The model included fixed effects of SA (0.47-0.53, 0.56-0.60, 0.64-1.13 m2/animal), SY (dry, rainy, north) and year (2012, 2013), the simple interactions and IW as a covariate. Mean IW, FW, FWA, DWG were 14.29±3.52, 35.75±3.11, 40.50±5.91 kg, and 286± 50 g, respectively, with 72.15± 14.45 of FP. The SA affected FW, FWA and DWG, SY affected only FW and YR affected significantly all the study variables. Lambs...

The aim of this study was to evaluate the effect of Ley-Leygo and Triladyl® extenders and two equilibrium times on individual motility (IM), plasma membrane integrity (PMI), mitochondrial activity (MA) and intact acrosome (IA) in frozen-thawed boar semen. A rich fraction of a total of 20 ejaculates from five boars of a commercial line was used. All ejaculates had a minimum of 80% motility and 85% normal spermatozoa. Each ejaculate was divided into four aliquots: Ley-Leygo and Triladyl® extenders and two equilibrium times (0 and 1 h). The semen samples were thawed at 37 °C for 20 s. The results of the IM and the PMI did not have significant effects for the factors evaluated (p>0.05). There was a significant difference for MA (p<0.05) between the Ley-Leygo (43.57%) and Triladyl® (51.7%) diluents. The IA was 46% for Ley-Leygo and 25% for Triladyl® (p<0.05). The percentage of ...

The aim of this study was to compare the profitability of fattening lambs under two types of housing in the subhumid tropics of Mexico. Data on production parameters and production costs of 32 lambs, 16 housed in raised pens and 16 in pens at ground level, were analysed to determine the cost-benefit relationship and profitability. The cost-benefit ratio and the profitability of fattening lambs in raised pens were superior compared to fattening lambs in pens at ground.

The aim of this study was to identify the foremost model that depict the lactation curve of dual-purpose crossbred cows under a humid tropical environment. Six models were compared to describe the lactation curves of three breed groups using 1231 milk records of 160 cows. The breed groups were 0-25%, F1 (50%) and 62.5-75% Holstein x Gyr crosses. Parameters of the models and curves were estimated using non-linear procedures. The best model was determined by the Akaike information criterion. Wood, Sikka and Wilmink models provided a good fit to the lactation curves for the breed groups; however, the Wood model was applied to depict the lactation curves, the day at which lactation peak was reached and milk yield at the peak. The aspect of the curves differed according to the breed group. The low graded Holstein cows had typical standard curves, and the F1 and high graded cows had no lactati...