Effects of pelleting temperature of phytase supplemented broiler feed on tibia mineralization, calcium and phosphorus content of serum and performance

摘要

The present study was conducted to determine the effects of different pelleting temperature on tibia mineralization, calcium, phosphorus content of serum and growth performance of broilers fed phytase-supplemented diets. The basal experimental diet type was typical maize-soybean meal. The basal diet was supplemented with a microbial 6-phytase (Novo CT: coated thermostable granulate, from Novo Nordisk A/S,Denmark) at 500 Phytase Units (FTU) per kg of feed before pelleting. The diets were pelleted at 65, 75, or 85°C except the basal mash diet as the control. The experimental diets were used from 0 to 6 weeks of age of birds. Dry matter, crude ash, Ca, total P, Na, K and Mg, Zn, Fe, Mn, Cu contents of tibia were not affected by the pelleting temperature. No effects of pelleting temperatures on Ca content in the serum were found out. However, P content in the serum was increased by feeding the diet pelleted at 65°C as compared to the control and other treatments. Pelleting at 65 and 75°C had a significant positive effect on body weights and body weight gains of broilers. It was concluded that the best pelleting temperature was 65°C. It is to note that the temperature of 85°C damages enzymatic activity.