The utility of a next generation biosynthetic bacterial 6-phytase(PhyG)in restoring bone ash,bone phosphorus(P)content and performance in piglets depleted in P was evaluated.A total of 9 treatments were tested as foll...The utility of a next generation biosynthetic bacterial 6-phytase(PhyG)in restoring bone ash,bone phosphorus(P)content and performance in piglets depleted in P was evaluated.A total of 9 treatments were tested as follows.Treatment 1,a negative control(NC)diet;treatments 2,3,4,NC supplemented with 250,500 or 1,000 FTU/kg of PhyG;treatments 5,6,NC supplemented with 500 or 1,000 FTU/kg of a commercial Buttiauxella sp phytase(PhyB);treatments 7,8,9,NC supplemented with monocalcium phosphate(MCP)to provide 0.7,1.4 and 1.8 g/kg digestible P,equating to a digestible P content of 1.8,2.5 and 2.9 g/kg.The latter constituting the positive control(PC)diet with adequate P and calcium(Ca).The NC was formulated without inorganic P(1.1 g digestible P/kg)and reduced in Ca(5.0 g/kg).Additional limestone was added to treatments 7 to 9 to maintain Ca-to-P ratio between 1.2 and 1.3.A total of 162 crossed Pietrain x(Large White×Landrace)21-d-old piglets(50%males and 50%females)were fed adaptation diets until 42 d old and then assigned to pens with 2 pigs/pen and 9 pens/treatment in a completely randomized block design.Piglets were fed mash diets based on corn and soybean meal ad libitum for 28 d.At the end of the study,one piglet perpen was euthanized and the right feet collected for determination of bone strength,bone ash and mineral content.Compared with the PC,the NC group had reduced average daily gain(ADG)and increased feed conversion ratio(FCR)during all growth phases and overall,and at d 28(70 d old)NC pigs had bones with reduced ash,Ca and P content(P<0.05).The PhyG at 250 FTU/kg improved bone ash vs.NC.Increasing PhyG dose linearly or quadratically improved bone ash,ADG and FCR(P<0.05).At>500 FTU/kg,both PhyG and PhyB maintained ADG and FCR equivalent to PC.Linear regression analysis was done to compare the measured response parameters to increasing digestible P from MCP.Based on this analysis it was shown that PhyG and PhyB at 1,000 FTU/kg could replace 1,83 and 1.66 g/kg digestible P from MCP in the diet,respectively,on average across metacarpi bone ash,ADG or FCR.These findings suggest that the biosynthetic phytase is highly effective in the tested dietary setting.展开更多
The experiment was conducted to evaluate the low phosphorus diets supplemented with different sources of phytase in low metabolizable energy （ME） and crude protein （CP） diets in broilers. Four levels of non-phytat...The experiment was conducted to evaluate the low phosphorus diets supplemented with different sources of phytase in low metabolizable energy （ME） and crude protein （CP） diets in broilers. Four levels of non-phytate phosphorus （NPP） （0.33%, 0.36%, 0.39% and 0.42% of the diet） were employed in six dietary treatments in such a way that the least level of NPP （0.33%） was supplemented with two phytase enzymes namely 6-phytase （Natuphos-5,000） and 3-phytase （Sunphase） along with low nutrient composition viz. 2750 kcal ME/kg and CP 18% in growing phase （21 d-42 d）. A total of 1,400 birds were exposed to six treatments in three replicates except for the phytase supplemented diets which were replicated four times each. Non-significant results are obtained from all performance parameters （body weight gain, feed intake and feed gain） and serum minerals （calcium and phosphorus） between 21 days to 42 days. Non-significant results are seen among all treatments; even supplementation of both types of enzymes did not affect the overall results. The results of the present study demonstrate 0.33% P level without phytase are sufficient in low ME and CP diets.展开更多
文摘The utility of a next generation biosynthetic bacterial 6-phytase(PhyG)in restoring bone ash,bone phosphorus(P)content and performance in piglets depleted in P was evaluated.A total of 9 treatments were tested as follows.Treatment 1,a negative control(NC)diet;treatments 2,3,4,NC supplemented with 250,500 or 1,000 FTU/kg of PhyG;treatments 5,6,NC supplemented with 500 or 1,000 FTU/kg of a commercial Buttiauxella sp phytase(PhyB);treatments 7,8,9,NC supplemented with monocalcium phosphate(MCP)to provide 0.7,1.4 and 1.8 g/kg digestible P,equating to a digestible P content of 1.8,2.5 and 2.9 g/kg.The latter constituting the positive control(PC)diet with adequate P and calcium(Ca).The NC was formulated without inorganic P(1.1 g digestible P/kg)and reduced in Ca(5.0 g/kg).Additional limestone was added to treatments 7 to 9 to maintain Ca-to-P ratio between 1.2 and 1.3.A total of 162 crossed Pietrain x(Large White×Landrace)21-d-old piglets(50%males and 50%females)were fed adaptation diets until 42 d old and then assigned to pens with 2 pigs/pen and 9 pens/treatment in a completely randomized block design.Piglets were fed mash diets based on corn and soybean meal ad libitum for 28 d.At the end of the study,one piglet perpen was euthanized and the right feet collected for determination of bone strength,bone ash and mineral content.Compared with the PC,the NC group had reduced average daily gain(ADG)and increased feed conversion ratio(FCR)during all growth phases and overall,and at d 28(70 d old)NC pigs had bones with reduced ash,Ca and P content(P<0.05).The PhyG at 250 FTU/kg improved bone ash vs.NC.Increasing PhyG dose linearly or quadratically improved bone ash,ADG and FCR(P<0.05).At>500 FTU/kg,both PhyG and PhyB maintained ADG and FCR equivalent to PC.Linear regression analysis was done to compare the measured response parameters to increasing digestible P from MCP.Based on this analysis it was shown that PhyG and PhyB at 1,000 FTU/kg could replace 1,83 and 1.66 g/kg digestible P from MCP in the diet,respectively,on average across metacarpi bone ash,ADG or FCR.These findings suggest that the biosynthetic phytase is highly effective in the tested dietary setting.
文摘The experiment was conducted to evaluate the low phosphorus diets supplemented with different sources of phytase in low metabolizable energy （ME） and crude protein （CP） diets in broilers. Four levels of non-phytate phosphorus （NPP） （0.33%, 0.36%, 0.39% and 0.42% of the diet） were employed in six dietary treatments in such a way that the least level of NPP （0.33%） was supplemented with two phytase enzymes namely 6-phytase （Natuphos-5,000） and 3-phytase （Sunphase） along with low nutrient composition viz. 2750 kcal ME/kg and CP 18% in growing phase （21 d-42 d）. A total of 1,400 birds were exposed to six treatments in three replicates except for the phytase supplemented diets which were replicated four times each. Non-significant results are obtained from all performance parameters （body weight gain, feed intake and feed gain） and serum minerals （calcium and phosphorus） between 21 days to 42 days. Non-significant results are seen among all treatments; even supplementation of both types of enzymes did not affect the overall results. The results of the present study demonstrate 0.33% P level without phytase are sufficient in low ME and CP diets.
