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The effects of supplementation with cellulase, xylanase, pectinase, hemicellulase, glucanase, phytase and protease of microbial origin on digestibility of crude protein (CP) and dry matter (DM) of soybean meal in vitro were examined in the present study. Changes in viscosity during in vitro digestion were also examined as an index of carbohydrate digestibility. Hemicellulase and all enzyme combinations without protease showed significant improvement of CP digestibility. Cellulase, xylanase, phytase and glucanase tended to improve CP digestibility. Dry matter digestibility was improved significantly by pectinase and all enzyme combinations. Cellulase and phytase tended to improve DM digestibility. Crude protein and DM digestibilities were the highest when all the enzymes except protease were added. Protease, cellulase, pectinase, xylanase, glucanase and hemicellulase significantly reduced viscosity, while phytase had no effect on viscosity. Viscosity was increased unexpectedly when all the enzymes were added. These results strongly suggest that a combination of carbohydrases improves the CP and DM digestibility of soybean meal while protease inhibits the actions of these enzymes. The present study also suggests that viscosity is not always a good index of digestibility. Moreover, excluding the protease from commercial crude enzyme preparations may improve digestibility.  相似文献   
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This study was conducted to show that dietary supplementation of a fungus, Aspergillus awamori called Koji in Japan, reduces skeletal muscle protein breakdown and stimulates growth in broiler chickens. A total of 30 chicks at 15 days of age was divided into control and two treatment groups (10 birds per treatment). Control group was fed basal diet and treatment groups were fed the basal diets supplemented with A. awamori at levels of 0.05% and 0.2%. The birds were raised for 12 days from 15 to 27 days of age and then the effect on growth, organ weights and plasma 3‐methylhistidine concentration and digestibilities of protein and energy was evaluated. The messenger RNAs (mRNAs) of atrogin‐1, ubiquitin, proteasome, m‐calpain, µ‐calpain, β‐actin, myosin and pax‐7 in the breast muscle were also measured. Body weight gain and breast muscle weight were increased, although feed intake was decreased by the fungus and thus feed efficiency was increased. Protein and energy digestibilities were increased. Furthermore, plasma 3‐methylhistidine concentration was decreased by the fungus. The mRNAs of atrogin‐1, ubiquitin, proteasome, m‐calpain and µ‐calpain were all decreased. The mRNA of β‐actin but not myosin and pax‐7 was slightly increased by the fungus. In conclusion, feeding A. awamori improves growth performance because skeletal muscle proteolytic activity is reduced and digestibilities of energy and protein are increased.  相似文献   
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The effects of purified cellulase and a commercial feed enzyme (FE) containing cellulase, hemicellulase, pectinase and so on, on the performance, abdominal fat content, digestibility of ileal contents and metabolizable energy of broilers were examined. Male broiler chicks (Cobb strain) were divided into three groups: control, cellulase (1 U/g feed) and FE (0.6 mg/g feed) with seven replicates. Chicks were raised under a temperature condition of 25°C in wire bottom cages for 12 days from 15 days of age. Feed (corn–soybean meal diet: crude protein, 21%; metabolizable energy, 3000 kcal/kg) and water were offered ad libitum. Dietary cellulase had a negative effect on the bodyweight gain and feed conversion ratio. The FE had no effect on bodyweight gain, but tended to improve the feed conversion ratio. The ileal crude protein and ash digestibilities were improved by the FE, but not by the cellulase. Furthermore, cellulase decreased the abdominal fat content and the FE increased metabolizable energy. In conclusion, digestion is enhanced and an improvement in performance is brought about by FE and, interestingly, fat metabolism is affected by cellulase by an unknown mechanism.  相似文献   
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In the present study, the synergistic effect of dietary cellulase and hemicellulase on the nutrient utilization, performance and digesta (content of jejunum) viscosity in broilers fed a corn–soybean meal diet were studied. The treatment groups included a control, cellulase (0.33 U/g feed), hemicellulase (2 U/g feed) and mixed enzyme (cellulase (0.33 U/g feed) + hemicellulase (2 U/g feed)) group. The enzymes were mixed with the basal diet (21.1% crude protein, 3000 kcal/kg metabolizable energy) and fed to male broiler chickens (Cobb strain) for 12 days from 15 days of age. Feed and water were offered ad libitum. Chicks were raised under 25°C in wire‐bottomed cages during the entire experimental period. We found that broilers given enzymes grew faster, and that the mixed enzyme was most effective. Feed intake remained the same for all of the treatment groups. Carcass weight was increased by mixed enzyme significantly, but not by cellulase and hemicellulase. The enzymes, but not mixed enzyme, decreased abdominal fat and were significant in the case of cellulase. Enzymes did not affect muscle weight and nitrogen‐retention, but metabolizable energy content of the diet was improved by the mixed enzyme. Ash‐retention was increased by hemicellulase and mixed enzyme. Digesta viscosity was significantly decreased by cellulase, but not by hemicellulase and the mixed enzyme. The results indicate that the combination of cellulase and hemicellulase has a synergistic effect on the performance of broilers fed a corn–soybean meal diet.  相似文献   
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The traditional method of processing fish waste is costly and usually overheats the waste, making it less digestible. In the present study, a fermentation technique using Aspergillus awamori was used to dry minced sardine fish to find a new model for processing fish waste and to evaluate its digestibility. Wheat bran (700 g), minced fresh sardines (2638 g) and A. awamori spores (0.7 g) were mixed together and kept in a ventilated incubator for 5 days at 40°C. At the end of the fermentation, a sample of fishmeal was taken to measure the nutrient content, enzyme activity and digestibility of crude protein (CP) and dry matter (DM) using an in vitro method. Furthermore, the effect of enzymes produced during the fermentation of DM and CP digestibilities of corn–soybean mixture in vitro were also examined. The percentage of moisture, CP, crude fat and nitrogen‐free extract in the fermented fish waste were 11, 39, 23 and 25%, respectively. The in vitro digestibilities of DM (69%) and CP (84%) of the fishmeal were almost the same as those of the heat‐dried sardine powder. During the fermentation, glucoamylase, α‐glucosidase, α‐amylase and acidic protease were produced, which may improve the DM digestibility of the diet. In conclusion, fish waste can be dried successfully using the fermentation technique described in the present study. Furthermore, the DM digestibility of the corn–soybean meal mixture is improved by the enzymes produced during the fermentation.  相似文献   
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