Chemical composition, digestibility and digestion kinetics of steam explosion-treated crop residues [Composición química, digestibilidad y cinética ruminal de la digestión de residuos agrícolas tratados con explosión de vapor]
Gutierrez R.B.,National Research Center Disciplinaria en Fisiologia Animal |
Vega S.M.,Autonomous University of Queretaro |
Rodriguez E.R.,National Research Center Disciplinaria en Fisiologia Animal |
Becerra J.B.,National Research Center Disciplinaria en Fisiologia Animal
Revista Mexicana De Ciencias Pecuarias | Year: 2012
Two experiments were conducted to determine the effects of steam explosion (STE) on chemical composition and digestibility of the following forages (F): sorghum stover (SOS), corn stover (COS) and sugarcane bagasse (SUB). The Exp 1 was conducted to determine the effects of STE on pH, fiber fractions (FF) and in vitro digestibility (IVDMD). Fifty four samples were generated using a RCB design with a 3*3*3 factorial treatment arrangement, where the factors were: pressure (P: 10.3, 13.8 and 17.2 kg/cm2), time (T: 5, 10 and 15 min) and F (SOS, COS and SUB). In Exp 2, changes in the digestion kinetics were determined when using the combinations of P and T that maximized IVDMD; thus, SOS and COS were treated at 13.8 kg/cm2 for 10 min, and SUB at 17.2 kg/ cm2 for 15 min. The treated and non-treated samples were incubated in rumen for up to 120 h. Data were fitted to a nonlinear model. No significant interactions T*P or F*P*T were detected on pH or FF; however, as P or T increased, pH, NDF and hemicellulose decreased. Lignin or ADF were not affected by P or T. As for IVDMD concerns, P*F and F*T interactions were significant. STE increased soluble fraction and degree of F digestion. Only lag time of SUB was reduced by STE. The potential digestible fraction was reduced in SOS and COS. It was concluded that the changes in chemical composition and digestion kinetics are related mainly to cell wall solubilization by stem explosion.
Bertol T.M.,Urbana University |
Bertol T.M.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuária |
Brana D.V.,Urbana University |
Brana D.V.,Instituto Nacional de Investigaciones Nucleares |
And 7 more authors.
Journal of Animal Science | Year: 2011
The effects of dietary energy source and feed withdrawal on muscle glycolytic potential (GP) and blood acid-base responses to handling were investigated in slaughter-weight pigs (initial BW 94.7 ± 1.01 kg). Crossbred pigs (n = 96; 48 barrows, 48 gilts) were used in a randomized complete block design with a 4 × 2 × 2 factorial arrangement of treatments: l) diet [control, high fat (10% supplemental fat), lowdigestible carbohydrate (20% total starch), and highfat/ low-digestible carbohydrate (10% supplemental fat and 20% total starch)]; 2) feed withdrawal (0 and 36 h); and 3) sex (barrow and gilt). Diets were fed for 28 d before the feed withdrawal treatment was applied, at the end of which all pigs were individually moved through a 12.20-m-long × 0.91-m-wide passageway for 16 laps (195 m total distance), with the assistance of an electric goad (2 times per lap). Longissimus muscle biopsies were collected at the beginning of the feeding and feed withdrawal periods and immediately after and 4 h after the handling procedure. Venous blood was collected 2 h before and immediately after the handling procedure to measure acid-base responses. At the end of the feeding period, pigs fed the control and high-fat diets were heavier (P < 0.001) than those on the lowdigestible carbohydrate and the high-fat/low-digestible carbohydrate diets (129.8, 130.9, 114.0, and 122.1 kg, respectively; SEM 1.91). Diet, feed withdrawal, and sex did not affect (P > 0.05) blood acid-base responses to handling. Muscle GP at the end of the feeding period and 4 h posthandling was least (P < 0.05) for pigs fed the high-fat diet and similar for the other 3 diet treatments. Pigs subjected to 36 h compared with 0 h of feed withdrawal had less GP (P < 0.05) immediately after and 4 h after the handling procedure. There was an interaction between diet and feed withdrawal treatments for changes in GP from the start of feed withdrawal to 4 h posthandling. The reduction in GP was greater (P < 0.05) for fasted than for fed pigs receiving the control and high-fat diets, but was similar (P > 0.05) for fasted and fed pigs receiving the 2 low-digestible carbohydrate diets. In conclusion, neither dietary energy source nor fasting affected blood acid-base responses to handling; however, fasting-induced changes in LM GP were diet dependent © 2011 American Society of Animal Science. All rights reserved.
Quichimbo C.,National Autonomous University of Mexico |
Quintana J.,National Autonomous University of Mexico |
Rodriguez-Saldana D.,Balanceados El Granjero |
Lopez-Coello C.,National Autonomous University of Mexico |
And 2 more authors.
International Journal of Poultry Science | Year: 2013
The effect of two nipple drinker heights on productive parameters and mortality of broilers up to day 42 was assessed. Birds were subjected to two treatments: 1) low height (the bird stretches the neck and drinks on the side of the beak); and 2) at a high level (the bird stretches the neck, pushing its chest upward and drinks with the point of the beak). Height was adjusted twice per week by visual observation of the birds at drinking time and observation of bedding level homogeneity in each experimental unit. Each treatment had 5 repetitions with 7 birds each one, handling and lodging followed broiler rearing recommendations, photoperiod was natural and water temperature was maintained at the recommended range (17 and 20 ̇C). Variables that were recorded each week were: feed consumption, body weight, feed conversion and mortality. The data analysis showed only numeric differences for the productive parameters, although accumulated mortality was 11.4% for the lower treatment and 25.7% for the higher one (P<0.10 Also, accumulated water consumption average per treatment per bird was 10,32 L for the low treatment and 9.621 L for the high treatment. Results suggest that the height of the nipple does not affect productive parameters, nevertheless it is an important factor to guarantee the amount and quality of water that is taken in to achieve maximum yield of poultry. © Asian Network for Scientific Information, 2013.
Becerra J.B.,National Research Center Disciplinaria en Fisiologia Animal |
Gutierrez R.B.,National Research Center Disciplinaria en Fisiologia Animal |
Martinez A.E.,Centro Investigaciones Avanzadas Del Estado Of Queretaro |
Rodriguez E.R.,National Research Center Disciplinaria en Fisiologia Animal
Tecnica Pecuaria en Mexico | Year: 2012
In the present study, rainfed cropping systems for maize and beans were evaluated in "W" type micro-watersheds. In a fluvisol soil, micro-watersheds with zero slopes were built at 1.6 m distance and 0.4 m high. Treatments were: conventional planting in furrows at 0.80 m (CP), planting in micro-watersheds (MW), with a row at one end and another at the edge, MW with a topological arrangement (MWT), with maize at the end and beans at the edge and MW planting maize in each slope (MWP). A completely randomized block experimental design with four replications was used. Rainfall at the experimental site was 398, 676 and 397 mm between July and September in 2006, 2007 and 2008, respectively. In 2006 MW output was greater than CP (P<0.05) for maize (29 and 39% grain and forage, respectively) and beans (40%). In 2007 and 2008 MW yield was similar to CP (P>0.05) and MWT maize yield improved on CP by 38 and 46% in 2007 and by 34 and 39% in 2008, in grain and forage, respectively, while MWP produced more maize forage (18%) and grain (27%) than CP (P<0.05). In the three research periods, lodging was observed in MW maize. MWT and MWP planting increases both maize and beans yield, improving water use efficiency in both grain and forage output.