Sunflower silage (SS) is being promoted as an efficient forage for feeding dairy cattle in the face of shortages of irrigation and erratic rainfall. The objective was to compare, through the in vitro gas production technique, the kinetics of ruminal fermentation of SS and its mixtures with maize silage (MzS) to know its nutritional characteristics before its inclusion in feeding strategies. Five combinations of SS with MzS were assessed (MzS%: SS%); T1) 100:0, T2) 75:25, T3) 50:50, T4) 25:75 y T5) 0:100. Combining MzS with 25% SS decreased neutral detergent fiber and acid detergent fiber contents (P<0.05), which resulted in a digestibility of dry mather, organic matter, neutral detergent fiber and metabolizable energy similar to MzS (P>0.05), and with a CP content not statistically higher than MzS. The MzS had the highest total gas production (GP) but at a lower fermentation rate (P<0.05) when compared to T2 that had a better fermentation rate of 0.0530 %/h, with Lag time of 3.4 h. Before ensiling, sunflower supplies 31.8 % more CP, 11.8 % less metabolizable energy and 11.9 % less in vitro digestibility of organic matter than maize plant. Compared to T1, the T2 supplied 1.6 % more crude protein, 2 % less metabolizable energy and 4.4 % less of in vitro digestibility of organic matter. Therefore it is concluded that sunflower silage could be an alternative to substitute up to 25 % of maize silage as the crude protein and metabolizable energy supply are similar to maize silage.

This paper has two objectives, the first is to determine the chemical composition, gas production parameters and the gas release kinetics, at different stages of maturity, of three grasses and a legume commonly found in long established pastures in (July, September and November 2003) and analysed using an in vitro gas production (GP) technique. The accumulated GP was fitted to the model described in PALMER et al. (2005)

Se evaluó el comportamiento productivo de bovinos doble propósito en un sistema silvopastoril intensivo (SSPi) en Apatzingán, Michoacán. La actividad se llevó a cabo mediante seguimiento técnico-económico. Asimismo, se monitorearon variables productivas y económicas (consumo de forraje, producción de leche, peso, ingresos y egresos) de 60 vacas de la raza Gyr analizadas mediante estadística descriptiva y presupuestos por actividad. La carga animal empleada fue de 2.06 UA ha-1 y la producción de leche obtenida fue 9.15 kg vaca-1 día-1. El manejo de vacas Gyr en un SSPi favorece la producción de leche y carne y el ingreso económico a la unidad de producción (UP).

Objective: Demonstrate the need to use locally generated data in the calibration of a near-infrared spectrometer (NIRS) in order to predict the chemical characteristics of fodder; instead of using data bases from other geographic regions, as is commonly done in Mexico. Design/Methodology/Approach: Two groups of samples collected in prairies of the central highlands of Mexico, the first group was used to calibrate the equipment; the equations generated were validated with a second group, collected in prairies that were different from the ones of the calibration group, but in the same geographic zone. Results: The best regression coefficients of the NIRS predictions, compared to traditional laboratory analyses were for crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), dry matter (DM) and organic matter (OM) (0.93, 0.87, 0.87, 0.56, 0.72 y 0.68 respectively). The lowest predictive value was observed in ashes (0.27). Limitations of the study/implications: The results show the need to use local materials in the calibration process. Conclusions: NIRS will make predictions of their chemical composition, since this is influenced by geographic origin of the sample and its botanical composition

Objective: Evaluate the physical-chemical properties and characterize the microstructure of four varieties of traditional Mexican chili (Capsicum annuum L.) powders: “Arbol”, “Guajillo”, “Piquin” and “Mole ranchero” (Ancho chili). Design/methodology/approach: Physical-chemical properties of chili powders were evaluated by means of moisture content, particle size, aerated and tapped bulk density, Carr index, Hausner ratio, angle of repose (flow properties), capsaicin, and carotenoids content. Microstructure of samples was characterized by Confocal Laser Scanning Microscopy and Scanning Electron Microscopy. ANOVA analysis and Tukey test were performed to evaluate the significant statistical difference between samples at 95% of confidence level. Results: “Arbol”, “Guajillo”, “Piquin” and “Mole Ranchero” chili powders presented a cohesive behavior respect to its flow properties related to aerated and tapped bulk density, angle of repose, Carr Index, and Hausner ratio values under moisture content between 6.59-14.48 gH2O/100g d.s. “Arbol” and “Piquin” chili powders presented the higher capsaicin content, while “Guajillo” and “Mole ranchero” showed the higher carotenoids content. FTIR spectra confirmed the presence of secondary amide, phenolic groups, alkanes, and aliphatic chains that belong to capsaicin structure at specific absorption bands. Microstructure of chili powders presented particles with surface imperfections as cracks and dents, and smooth surface that influence physical-chemical and flowability properties. Limitations on study/implications: Hight moisture content affect the physical-chemical properties, flowability and microstructure of traditional Mexican chili powders. Findings/conclusions: Moisture content between 6.59 and 14.48 gH2O/100g d.s. influences the physical-chemical properties, flowability and microstructure of traditional Mexican chili powders. To improve physical-chemical properties and flowability behavior of chili powders is required that moisture content be lower than 6.59 H2O/100g d.s.