An overview on production, consumer perspectives and quality assurance schemes of beef in Mexico.

Mexico has a large beef production industry that has grown significantly in the last decade. The export market has increased, however, domestic beef consumption has declined. A knowledge of the factors affecting consumer perceptions and acceptance of beef might highlight critical points that could improve the whole industry, and lead to an increase of export and domestic consumption. The present paper is aimed to provide an overview on the dynamics of Mexican beef production systems, the current perceptions of the Mexican consumer for beef, and the current available beef quality assurance schemes, based on published and official information.

Caffeoyl and coumaroyl derivatives from Acacia cochliacantha exhibit ovicidal activity against Haemonchus contortus.

ETHNOPHARMACOLOGY RELEVANCE: Acacia cochliacantha is a small tree whose foliage is traditionally used in Mexico for treatment of kidney pain, gastrointestinal illnesses and to kill intestinal parasites. In recent decades, the study of vegetal extracts has offered other possible alternatives for the control of Haemonchus contortus. Considering that this nematode affects dramatically the health and productivity of small ruminants, the aim of this study was to identify the anthelmintic compounds from A. cochliacantha hydro-alcoholic extract (HA-E) through an ovicidal test. MATERIAL AND METHODS: In vitro egg hatch assay was conducted to determinate the anthelmintic effects of a HA-E (60g). Liquid-liquid ethyl acetate/water extraction gave two fractions (EtOAc-F, 1.92g; Aq-F; 58.1g). The less polar compounds from ethyl acetate fraction were extracted by addition of dichloromethane offering a precipitate phase (Mt-F, 1.25g) and a soluble mixture (DCMt-F 1.15g). All fractions were evaluated for ovicidal activity obtaining the egg hatching inhibition (EHI, 0.07-25mg/mL). Ivermectin (0.5mg/mL) was used as a reference drug (positive control), and distilled water, 2.5% DMSO and 2% methanol were used as negative controls. The isolated compounds from the most active fractions were subjected to spectroscopic (1H NMR) Spectrometric (MS) and UV HPLC analysis in order to identify the bioactive compounds. RESULTS: The less polar treatments (AcOEt-F, DCMt-F, DCMt-P) showed the highest ovicidal activities (98-100% EHI; at 0.62-1.56mg/mL) and the major compounds found in these fractions were identified as caffeoyl and coumaroyl derivatives, including caffeic acid (1), p-coumaric acid (2), ferulic acid (3), methyl caffeate (4), methyl-p-coumarate (5), methyl ferulate (6) and quercetin. In case of the less active fractions (Aq-F, Mt-F) were constituted principally by glycosylated flavonoids. CONCLUSION: These results show that caffeoyl and coumaroyl derivatives from Acacia cochliacantha leaves had promising anthelmintic activity against Haemonchus contortus. This leguminous may offer an alternative source for the control of gastrointestinal nematodes of small ruminants.

In vitro gas production of foliage from three browse tree species treated with different dose levels of exogenous fibrolytic enzymes.

The aim of this study was to evaluate the effect of different dose levels of exogenous fibrolytic enzymes (EFE) on in vitro ruminal fermentation kinetics and energy utilization of foliages from three browse trees (Pithecellobium dulce, Heliocarpus velutinus and Guazuma ulmifolia). Mixture of EFE product was added to the leaves of the three browse tree species at three dose levels: 0 (control), 3.5 and 7.0 mg/g of DM. Chemical composition of the foliages, including plant secondary metabolites such as total phenolics (TP), saponins (SAP) and aqueous fraction (AF), was determined. In addition, in vitro assaying of ruminal gas production kinetics was determined for the three browse three foliages treated with EFE. P. dulce had the highest crude protein content (p < 0.05), whereas G. ulmifolia had the highest content of neutral detergent fibre and SAP (p < 0.05) and H. velutinus had the lowest content of TP (p < 0.05). The interaction between tree species and dose level of EFE was significant (p < 0.05) for gas production (GP) at 24 h of incubation, parameters b and c of the accumulated GP curve, short-chain fatty acids (SCFA) and metabolizable energy (ME). The lowest (p < 0.01) extent of accumulated GP as well as the b and c values occurred in G. ulmifolia at 0 mg EFE/g DM. P. dulce had the highest (p < 0.05) values for ME and SCFA at the highest dose of EFE. Tree species and dose level had significant (p < 0.05) effects on all parameters describing in vitro ruminal fermentation kinetics and energy utilization. Addition of EFE improved the fermentation kinetics of the browse species considered in this study.