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1.
Br Poult Sci ; 49(2): 164-75, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18409090

RESUMEN

1. Three experiments of 39 d were simultaneously conducted to assess the efficacy of three carbohydrase combinations on performance, apparent nutrient digestibility, intestinal morphology and digestive organ relative weights of chickens fed on a wheat-based diet. 2. Experiment 1 was performed under laboratory conditions, with the birds housed in cages. In experiment 2, the birds were placed in floor pens built in a commercial farm, and raised with their contemporaries at the farm. In experiment 3, broilers were reared under industrial management circumstances in commercial farms. A two-phase feeding programme was used: starter from 1 to 21 d of age and finisher from 22 to 39 d. The basal diet without supplementation (BD) and three enzyme preparations (BDF, BDP and BDR) were evaluated. 3. No differences in growth traits were observed among treatments in experiments 1 and 2. 4. When overall growing period was evaluated, all enzyme combinations improved apparent DM ileal digestibility of feed in the three experiments, but significant differences were only found in experiments 2 and 3. For this same period, an increase in apparent CP ileal digestibility of broiler chickens fed supplemented diets against the control group was found in experiment 3. Moreover, a significant greater apparent ileal fat digestibility in the enzyme treatments compared with the control group was shown when broilers were raised under industrial conditions (experiment 3). 5. Enzyme combinations had no effect on villus heights and crypt depths of broilers in experiment 1, whereas, in experiment 2, a greater villus height was found in BDF and BDP treatments than in control birds. 6. There were no differences in digestive organ relative weights among dietary treatments except for pancreas in experiment 1.


Asunto(s)
Pollos/crecimiento & desarrollo , Dieta , Digestión/efectos de los fármacos , Glicósido Hidrolasas/administración & dosificación , Triticum , Animales , Pollos/anatomía & histología , Suplementos Dietéticos , Sistema Digestivo/anatomía & histología , Endo-1,4-beta Xilanasas/administración & dosificación , Femenino , Glucano Endo-1,3-beta-D-Glucosidasa/administración & dosificación , Mucosa Intestinal/metabolismo , Intestinos/anatomía & histología , Masculino , Tamaño de los Órganos
2.
Poult Sci ; 81(7): 987-94, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12162360

RESUMEN

Wheat contains 5 to 8% nonstarch polysaccharides (NSP). The NSP complex forms a viscous mass when fully hydrated, which impedes the absorption of nutrients from chyme and causes reduced growth performance and osmotic diarrhea and associated wet litter. These adverse effects can be alleviated by appropriate enzyme supplementation. The objective of this experiment was to evaluate the efficacy of endoxylanase and beta-glucanase enzyme mixtures supplemented to wheat-based diets on growth performance characteristics of turkeys. Seven-day-old Large White male turkeys were randomly assigned to 40 litter floor pens of 12 poults each as a completely randomized block design arrangement of four experimental treatments and were raised to 140 d. The dietary treatment consisted of a control treatment (no supplemental enzyme) and three dietary enzyme treatments: 1) Lyxasan forte, 2) Natugrain Blend, and 3) Natugrain. Body weight, feed consumption, and mortality were recorded weekly. Feather condition was evaluated at 98 d of age. Natugrain Blend improved BW at 84 d (P < 0.075) and 112 d (P < 0.01) in comparison to the unsupplemented control diet. Lyxasan forte had the best feed/gain ratio throughout the experiment. Subjective feather condition score was significantly improved (P < 0.05) by all the three enzyme treatments and corresponded with reduced incidence of neck and back picking behavior. The enzyme treatment groups had lower mortality than the control group with the Natugrain blend treatment having the lowest mortality rate through the experiment. The results of this experiment demonstrate marginal improvement in growth performance of turkeys depending upon enzyme formulation.


Asunto(s)
Glucano Endo-1,3-beta-D-Glucosidasa/administración & dosificación , Triticum , Pavos/fisiología , Xilosidasas/administración & dosificación , Animales , Conducta Animal , Suplementos Dietéticos , Ingestión de Alimentos , Endo-1,4-beta Xilanasas , Plumas , Masculino , Pavos/crecimiento & desarrollo
3.
J Dairy Sci ; 83(3): 543-53, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10750113

RESUMEN

The objective of this study was to evaluate a commercial feed enzyme product (Natugrain 33-L; BASF Corporation, Ludwigshafen, Germany) used mainly in poultry diets for use in ruminant diets. The product contained mainly beta-glucanase, xylanase, and endocellulase activities. The study was conducted as a double 3 x 3 Latin square design with six lactating dairy cows (84 +/- 12 DIM) to measure intake, chewing activities, total tract digestion, and milk production. An additional three cows fitted with ruminal cannulae were used to measure dietary effects on ruminal fermentation and in sacco digestion characteristics. Cows received a diet consisting of 45% forage containing 0, 1.22, or 3.67 L of enzyme product/tonne of total mixed ration (DM basis). Using a low or high concentration of enzyme supplementation increased feed intake, but total tract digestibility only increased with the low concentration of enzyme. As a result, intake of digestible nutrients was increased to a greater extent for cows fed the low concentration than for cows fed the high concentration. Because the cows used in this experiment were in positive energy balance, increased intake of digestible energy due to enzyme supplementation did not increase milk yield or milk component yield. Further research is necessary to determine the mechanism by which adding a fibrolytic enzyme mixture enhanced intake, but only increased feed digestion when used at a low level.


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Bovinos/fisiología , Digestión , Glicósido Hidrolasas/administración & dosificación , Animales , Peso Corporal , Celulasa/administración & dosificación , Femenino , Fermentación , Glucano Endo-1,3-beta-D-Glucosidasa/administración & dosificación , Lactancia , Rumen/metabolismo , Xilano Endo-1,3-beta-Xilosidasa , Xilosidasas/administración & dosificación
4.
J Dairy Sci ; 81(5): 1353-7, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9621238

RESUMEN

A microbial and enzyme supplement fed at 21.2 g/d per cow to 46 Virginia dairy herds increased the milk yield of 31 herds (17 significantly) and decreased the milk yield of 15 herds (7 significantly). Effects of season were important but consistent with overall results. Herds began receiving the supplement, which contained dried fermentation products of Aspergillus oryzae, Bacillus subtilis, Lactobacillus acidophilus, and yeast culture, midway between the first and second monthly Dairy Herd Improvement tests and continued on the supplement through the 3rd mo. Entry of herds was staggered over 8 mo to reduce the influence of season. The trial involved 3417 cows with 5 test mo between 60 and 365 d in milk. Milk yield during mo 3 averaged 0.64 kg/d per cow more (+0.73 kg/d for first lactation cows and +0.56 kg/d for later lactation cows) than the mean milk yield during mo 1 and 5. Herds completing the study before summer responded similarly to all other herds, which included herds that were fed the product during summer and those that finished the study during summer. Fat and protein yields and protein percentage differed little with or without the supplement. Fat percentage decreased (0.10%). Twenty-one herds that were fed a yeast product prior to and during the study responded similarly to the 17 herds that were not fed a yeast product.


Asunto(s)
Bacterias , Bovinos/fisiología , Lactancia/fisiología , Probióticos , Saccharomyces cerevisiae , Animales , Aspergillus oryzae , Bacillus subtilis , Celulasa/administración & dosificación , Femenino , Fermentación , Glucano Endo-1,3-beta-D-Glucosidasa/administración & dosificación , Glicósido Hidrolasas/administración & dosificación , Lactobacillus acidophilus , alfa-Amilasas/administración & dosificación
5.
Br Poult Sci ; 36(4): 599-603, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8590092

RESUMEN

1. Three groups of birds were fed for up to 35 days on diets containing 500 g barley (cv. Condor)/kg diet, with or without exogenous beta-glucanase, either a commercial preparation or a recombinant endoglucanase. 2. Birds which received diets containing the exogenous enzymes grew faster for the first 3 weeks but after that there was no apparent difference in rate of growth. 3. beta-Glucanase activities in the crop and small intestine of birds given exogenous enzymes were generally higher than those of birds given only the basal diet. 4. Viscosity of intestinal fluid in birds given only the basal diet decreased with age but there was no corresponding increase in beta-glucanase activity. This discounts bacterial beta-glucanase as a contributory factor in the adaptation to beta-glucanase apparent in older birds.


Asunto(s)
Celulasa/metabolismo , Pollos/crecimiento & desarrollo , Pollos/metabolismo , Dieta/veterinaria , Glucano Endo-1,3-beta-D-Glucosidasa/metabolismo , Hordeum/normas , Secreciones Intestinales/enzimología , Intestino Delgado/enzimología , Animales , Celulasa/administración & dosificación , Clostridium/enzimología , Dieta/efectos adversos , Escherichia coli/enzimología , Glucano Endo-1,3-beta-D-Glucosidasa/administración & dosificación , Glucanos/administración & dosificación , Glucanos/efectos adversos , Secreciones Intestinales/fisiología , Distribución Aleatoria , Proteínas Recombinantes/farmacología , Viscosidad , Aumento de Peso
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