Xylanase, protease and superdosing phytase interactions in broiler performance, carcass yield and digesta transit time

作     者：Tiago T.dos Santos Helen V.Masey O'Neill Gemma González-Ortiz Daniel Camacho-Fernández Carlos López-Coello 

作者机构：AB Vista Facultad de Medicina Veteriaria y ZootecniaUniversidad Nacional Autónoma de México 

出 版 物：《Animal Nutrition》 (动物营养（英文版）)

年 卷 期：2017年第3卷第2期

页      面：121-126页

核心收录：

学科分类：0710[理学-生物学] 090502[农学-动物营养与饲料科学] 0905[农学-畜牧学] 09[农学] 0906[农学-兽医学] 

主　　题：Sorghum Tibia ash Sub-additivity Exogenous enzyme 

摘      要：The interaction of xylanase, protease and superdosing(1,500 FTU/kg) phytase in a 2×2×2 factorial arrangement was studied in broilers fed sorghum-based diets. A total of 2,800 one-day-old unsexed Ross308 chicks were housed in 56 pens with 50 birds per pen, with or without inclusion of xylanase, protease and phytase, totaling 8 treatments and 7 replicates per treatment. Body weight(BW) and feed intake(FI)were measured at 21 and 42 days of age, and mortality corrected feed conversion ratio(FCR) was calculated for each period and cumulatively. Tibia ash and carcass yield were determined in 2 birds per replicate at 21 and 42 days of age, respectively. Digesta transit time was determined at 21, 28, 35 and 42 days of age using 5 birds per replicate. Results showed that superdosing phytase increased BW and FI at42 days of age(P 0.05) and xylanase improved FCR(P 0.05). Xylanase and phytase also positively influenced carcass yield and breast weight, respectively. Overall, inclusion of superdosing phytase increased transit time when included in a diet containing xylanase, and no change with protease inclusion. In conclusion, the beneficial effects of xylanase, protease and superdosing phytase in broiler performance were not additive. This limitation is likely not related to the lack of efficacy of any one of the individual enzymes but to a limitation of the bird to respond additively to successive additions of enzymes.