There are unknown interactions between supplements of exogenous fibrolytic enzymes (EFE) and the cell walls of feedstuff in ruminal conditions. The quantitative effects of using EFE in ruminant diets were evaluated using meta-analysis. Records (586) were extracted from 74 journal articles from a list of published papers (2000-2012). Statistical analyses were performed considering fixed [type of foragebased diet, forage-to-concentrate ratio (F:C ratio) and primarily enzyme activities in the EFE], and random effects [Experiment(Article)]. In dairy cows fed high-forage (F:C ≥50%), the supplementation of primarily mixtures of cellulases and xylanases (Cel:Xyl: 1:4-1:1) increased milk production and milk composition of legume-based diets, and primarily xylanases (Xyl) EFE improved those variables of grass-based diets. In F: C <50% grass-based diets, Cel:Xyl improved the average daily gain (ADG) and feed conversion [FC:DM intake (DMI)/ADG] of beef cattle. DMI of dairy cows was not affected by EFE supplementation, but EFE improved the DMI of beef cattle. EFE effects were inconsistent in sheep productive performance variables. Cellulases (Cel) and Xyl enhanced in vivo dry matter (DM) digestibility (DMD) in low-forage (F:C <50%) grass-based diets. In F:C ≥50% legume-based diets, EFE enhanced the in situ DM disappearance (ISDMD), and mainly Cel:Xyl improved the in situ neutral detergent fibre (NDF) disappearance (ISNDFD), but there were no effects in those variables in F:C ≥50% grass-based diets. Regardless of the type of ruminal liquid (RL) or forage, in F:C ≥50% diets, in vitro DM degradability (IVDMD) was improved mainly by Cel, but fibre degradability only was improved by Cel:Xyl when sheep RL was used for in vitro evaluations. Overall, EFE could improve the productive performance of dairy cows and beef cattle, but the response depends upon the proper mixture of Cel and Xyl according to the diet composition.

The aim of this research was to identify the factors that influence the efficiency in the adoption of innovations in protected agricultural systems. For the study of these factors, a hierarchical cluster analysis was performed in which three clusters were obtained that showed clearly differentiated behavior. To identify the differences between groups, a variance analysis and a chi-square test was performed. The results show that efficiency in the adoption of innovations is related to the producer’s schooling, his experience, and access to extension services. Derived from the above, it is important to promote greater articulation among producers, promote an integral extensionism capable of promoting collective development and interactions that are developed and evolved in the territories.

The objective was to review the potential effects of adding anthocyanin delphinidin-3-O-sambubioside (DOS) and cyanidin-3-O-sambubioside (COS) of HS in animal diets. One hundred and four scientific articles published before 2021 in clinics, pharmacology, nutrition, and animal production were included. The grains/concentrate, metabolic exigency, and caloric stress contribute to increasing the reactive oxygen species (ROS). COS and DOS have antioxidant, antibacterial, antiviral, and anthelmintic activities. In the rumen, anthocyanin might obtain interactions and/or synergisms with substrates, microorganisms, and enzymes which could affect the fiber degradability and decrease potential methane (CH4) emissions; since anthocyanin interferes with ruminal fatty acids biohydrogenation (BH), they can increase the n-3 and n-6 polyunsaturated fatty acids (PUFA), linoleic acid (LA), and conjugated linoleic acid (CLA) in milk and meat, as well as improving their quality. Anthocyanins reduce plasma oxidation and can be deposited in milk and meat, increasing antioxidant activities. Therefore, the reduction of the oxidation of fats and proteins improves shelf-life. Although studies in ruminants are required, COS and DOS act as inhibitors of the angiotensin-converting enzyme (ACEi) and rennin expression, regulating the homeostatic control and possibly the milk yield and body weight. By-products of HS contain polyphenols as calyces with positive effects on the average daily gain and fat meat quality.

El objetivo fue estimar la tasa de pérdida de colonias de abejas melíferas (Apis mellifera) durante el invierno de 2015-2016 en las regiones del altiplano y norte de México. Se encuestaron 196 apicultores (n = 41 907 colonias). La tasa promedio de pérdida de colonias en ambas regiones fue del 33.4%, no se presentaron diferencias sig-nicativas (p > 0.05) entre regiones. Los apicultores encuestados estiman que las principales causas de pérdida fueron: el mal tiempo, enfermedades, insecticidas, evasión y la enjambrazón. No hubo efecto del tamaño de las explotaciones apícolas respecto a la tasa de pérdida de colonias. El presente estudio representa la primer estimación en dos regiones de México sobre la tasa de pérdida de colonias en el periodo invernal y que ésta es similar a la de otros países. Se sugiere implementar técnicas de manejo que contribuyan a mitigar los efectos del mal clima, las enfermedades, plagas y la africanización.

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