Performance and histological responses of internal organs of broiler chickens fed raw, dehulled, and aqueous and dry-heated kidney bean meals

The objective of the present study was to investigate the effect of raw and differently processed [aqueous heating, dehulled, and dry heating (toasted)] kidney bean meals on the performance, weights, and histology of internal organs of broiler chicken. The feeding trial lasted for 56 d. Two hundred twenty-five 1-d-old broiler chicks (Anak strain) were used for the study. There were 5 treatment groups of 3 replicates with 15 birds per replicate. Raw and processed kidney bean meals were used to replace 50% protein supplied by soybean in the control diet. Data collected were used to evaluate feed intake, weight gain, and efficiency of feed utilization. The weights of liver, pancreas, kidney, heart, and lungs were also recorded and tissue samples of each collected for histological examination. Average daily food intake, average daily gain, and efficiency of feed utilization were influenced by the dietary treatments. Average daily food intake and average daily gain in birds fed the control diet and heat-treated kidney bean meals were similar and significantly (P < 0.05) higher than those fed raw or dehulled meals. Feed conversion ratio was significantly (P < 0.05) higher in birds fed raw or dehulled meals compared with those fed the control diet. The relative weight of the pancreas was significantly (P < 0.05) increased as a result of acinar hypertrophy. The kidney had severe congestion of glomeruli and distention of the capillary vessels with numerous thrombi in birds fed raw and dehulled kidney bean meals. The weight of the liver was significantly (P < 0.05) reduced in birds fed raw and dehulled meals, and the liver was characterized by marked coagulative necrosis and degeneration of the hepatocytes. The structural alterations were attributed to intake of trypsin inhibitors and haemagglutinins in the processed seeds. In conclusion, aqueous heated kidney bean meal can be used to replace 50% protein supplied by soybean meal in broiler starter and finisher diets without any adverse effect on the performance and the internal organs.