Document Type : Research Paper

Authors

1 PhD student, Department of Animal and Poultry Nutrition, Faculty of Animal Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran

2 Professor, Department of Animal and Poultry Nutrition, Faculty of Animal Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran

3 َAsscociate Professor, Department of Animal Science, Varamin-Pishva Branch, Islamic Azad University, Varamin, Iran

4 Assistant Professor, Department of Animal and Poultry Nutrition, Faculty of Animal Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran

5 Professor, Animal Science Research Institute of Iran, Agricultural Research, Education and Extension Organization, Karaj, Iran

6 MSc Gradate, Young Researchers and Elite Club, Tehran Science and Research Branch, Islamic Azad University, Tehran, Iran Karaj, Iran

Abstract

A total of 1440 Ross 308 male broilers was used in a randomized complete block design with eight treatments in six blocks from 1 to 42 d. Experimental diets were: soybean meal (control treatment), raw soybeans, full-fat soybeans extruded (15%) at 90 and 150 °C, with (0.02%) or without protease enzyme supplementation. The use of raw soybeans compared to soybean meal or extruded full-fat soybean significantly reduced feed intake, body weight and relative carcass weight, as well as increased feed conversion ratio and pancreatic weight (P <0.01). weight gain was improved in diets supplemented by protease enzyme compared to diets containing raw soybeans (P <0.01). Feed conversion ratio was improved in diets containing raw soybean and soy bean meal by dietary protease supplementation (P <0.01). Extrusion temperature did not affect the growth performance of experimental birds. Diet containing raw soybean without enzyme increased blood cholesterol levels (P <0.05). According to the findings of this study, the use of protease enzyme in diets containing soybean meal or raw soybean can improve the performance of broilers However, such an effect is less pronounced in diets containing extruded full-fat soybean meal.

Keywords