The objective was to evaluate the effect of fodder tree species (FTS) with condensed tannin contents: Cordia elaeagnoides, Platymiscium lasiocarpum, Vitex mollis, and Haematoxylon brasiletto, on in vitro methane (CH4) production at 24 h post incubation. The analysis was performed using the in vitro gas production technique, with three levels of inclusion/species: 600, 800, and 1,000 mg and with 4 replicates/species/level of inclusion. The substrate was incubated at 39°C, and the gas and CH4 production were recorded at 4, 8, 12, and 24 h post incubation. The data collected was analyzed through Pearson correlation, polinomial regression and fixed effects models. There were negative correlations between FTS-total gas volume (r = −0.40; p<0.001); FTS-volume of CH4 produced (r = −0.40; p<0.001) and between the inclusion level-volume of CH4 produced (r = −0.20; p<0.001). As well as a positive correlation between hours post incubation-total gas volume (r = 0.42; p<0.001) and between hours post incubation-volume of CH4 produced (r = 0.48; p<0.001). The FTS: C. elaeagnoides, V. mollis, and H. brasiletto have potential, in the three inclusion levels analyzed, to reduce CH4 emission on in vitro trials (>32.7%), taking into account the total CH4 production at 24 h of the forage used as reference (Avena sativa). It’s suggested that C. elaeagnoides-according to its crude protein, neutral detergent fiber, and condensed tannins content- is the best alternative within the FTS analyzed, for feeding ruminants and for the control of CH4 emissions during the dry season.

Objective. Determine the best non-linear model to fit the growth curve of local turkeys managed under confinement in Michoacan, Mexico. Material and methods. Twenty-four and 43 female and male turkeys, reared under commercial conditions were given commercial feed. Birds were weighed weekly from hatch to 29 weeks of age. The Gompertz, Brody, Richards, von Bertalanffy and Logistic models were chosen to describe the age-weight relationship. Results. The best fitting model was selected based on the multiple determination coefficient (R2), the Akaike information criterion (AIC) and visual analysis of the observed and predicted curves. In both female and male, von Bertalanffy was the best model. The highest estimates of parameter A (mature weight) for both females and males were obtained with the von Bertalanffy model followed by the Gompertz and Logistic. The estimates of A were higher for males than for females. The highest estimates of parameter k (rate of maturity) for both females and males were, in decreasing order, for the Logistic, Gompertz, and von Bertalanffy models. k values for female turkeys was higher than for males. The age at the point of inflection (TI) and body weight at the age of point of inflection (WI) varied with the model used. The largest values of TI and WI corresponded to the Logistic model. Between sexes, the largest TI and WI values corresponded to males. Conclusions. The best models to describe turkey growth was the von Bertalanffy because it present the highest R2 and lowest AIC values.

Abstract:The aim of this study was to evaluate the use of melengestrol acetate (MGA) as a strategy to improve the production efficiency in ewes of rural areas in México. Twenty ewes of breeds (Dorper and Dorper with Pelibuey) non-pregnant and with ovarica activity were used. The treatment consisted of the administration of 0.22 mg MGA/ewe/d for 17 d. The MGA efficiency was measured once the treatment finalized, and the producer was responsible for the registration of the estrus presentation and prolificacy rate. 95% of the sheep presented estrus in a period of 14 d after stopping treatment. The prolificacy percentage was of 1.2 lambs born by ewe during a period of six months (including treatment and period of gestation). In conclusion, the use of MGA represents an alternative to improve the efficiency of sheep production in rural areas in México, since it can increase the number of lambs by 30% in a period of 12 months.

The production model intensive silvopastoral system must be evaluated from three perspectives of sustainable development: economic, social and environmental. The evaluation has been the most important economic aspect; while the environmental part has only been evaluated as justification to funding research and the social aspect was downplayed. The objective of this study was to know the social contribution through adoption intensive silvopastoral systems in Tierra Caliente, Michoacán. The information was provided by farmers through interviews. The data were diffusion source of the intensive silvopastoral system, year of diffusion the production model, production objective of intensive silvopastoral system, benefits perceived by the adoption of the production model and factors that influenced in implementing the intensive silvopastoral system. Since 2006, NGO have played an important role in the dissemination, implementation and adoption of these productions model. Intensive silvopastoral systems have been implemented with livestock objectives; farmers said they have received benefits by the adoption; the most influential factor in the implementation of the intensive silvopastoral system was the confidence generated from the experiences and previous results in other farmers. The adoption of intensive silvopastoral systems, increase the productivity and profitability of production units in addition to promoting environmental sustainability and social welfare. 

Abstract-In this paper a system for reducing contamination risks in the methodology of analysis and critical control points (HACCP) was applied. The job gets done in a municipal slaughterhouse in the state of Michoacán, Mé xico, through the HACCP methodology and under the official Mexican standards (NOM) for its acronym in Spanish. This hard work 180 days, an analysis at the beginning and after applying the HACCP prerequisites were applied, the five preliminary tasks and the seven principles of HACCP is performed. The results show that the trail has 20 years of operating and investment not received with the application of HACCP pollution was reduced during the process but this is not enough and that the part of provider deficiencies found.Index Terms-System contamination risk reduction, hazard analysis and critical control points, slaughterhouse.