RESUMEN
BACKGROUND AND OBJECTIVES: Supplementing diets of dairy animals with phytase and xylanase can enhance phosphorus availability and fiber degradation in the rumen and positively affect animal's health and productivity. In vitro and in vivo trials have been conducted to define the optimal addition level of xylanase and phytase to lactating Baldi goat's rations and investigate effects of these enzymes on animal's nutrients digestibility, blood chemistry, milk production and milk composition. MATERIALS AND METHODS: In vitro batch culture technique was used to evaluate the effect of phytase and xylanase supplementation at different levels (0, 1, 2 and 3 g kg-1 DM) on rumen fermentation characteristics. Eighteen early lactating Baldi goats were randomly assigned into three groups and fed 4% dry matter according to their body weight. The first group was fed control ration (35% yellow corn, 20% corn stalks, 20% berseem hay, 12.5% soybean meal and 12.5% wheat bran), the second group fed control ration+Penizyme at 2 g kg-1 DM (R1), while the third group fed control ration+Phtase-Plus® at 1 g kg-1 DM (R2). RESULTS: Xylanase and phytase supplementation increased the in vitro DM and OM degradability and ruminal NH3-N and total volatile fatty acids (TVFA) concentrations, with no effect on total gas production (TGP) volume. All nutrients digestibility (except CP), blood serum glucose concentration, milk production and milk components yields were increased for enzymes supplemented goats than control. CONCLUSION: Inclusion of xylanase and phytase in lactating goat's rations improved their productive performance with no deleterious effects on their health.
Asunto(s)
6-Fitasa/uso terapéutico , Suplementos Dietéticos , Endo-1,4-beta Xilanasas/uso terapéutico , Cabras , Lactancia/efectos de los fármacos , Leche/química , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Peso Corporal , Ácidos Grasos/química , Femenino , Fermentación , RumiantesRESUMEN
The present study was carried out to evaluate the protective effects of xylanase on the intestinal mucosal barrier in broiler chickens challenged with Clostridium perfringens in a 21-day experiment. A total of 336 1-day-old male broiler chicks (Ross 308) were assigned to four treatment groups. A 2×2 factorial arrangement of treatments was used in a randomized complete block design to study the effects of enzyme addition (with or without xylanase 5500 U/kg wheat-based diet), pathogen challenge (with or without C. perfringens challenge), and their interactions. Most C. perfringens-challenged birds had a congested mucosa and focal haemorrhagic lesions in the jejunum. Xylanase addition tended to reduce (P=0.09) the intestinal lesion score in the challenged birds. C. perfringens challenge resulted in decreased villus height/crypt depth ratio in the jejunum and ileum (P<0.05). Xylanase supplementation significantly increased this ratio in the jejunum (P<0.05) and also had the tendency to decrease crypt depth (P=0.065) and increase this ratio in the ileum (P=0.087). Xylanase addition significantly decreased the plasma endotoxin levels of the birds challenged with C. perfringens (P<0.05). Occludin mRNA expression in the jejunum and ileum was significantly decreased by C. perfringens challenge (P<0.05), but xylanase addition significantly increased its expression in the ileum. Xylanase supplementation also significantly increased MUC2 mRNA expression in the ileum (P<0.05). C. perfringens challenge resulted in a significant increase in apoptotic index in all three intestinal segments (P<0.05), but xylanase supplementation obviously decreased apoptotic index in the ileum (P<0.05). In conclusion, xylanase supplementation could alleviate the impairment of intestinal mucosal barrier induced by C. perfringens challenge.