Changes in a-amylase activity of the pancreas, plasma, crop tissue and crop content related to age and sex were determined in chicks and the correlation among the pancreas, plasma, crop tissue and crop content were investigated. A total of 336 ISA- 5 broiler hybrid chicks were used as material. The chicks were separated into two groups: 224 males and 112 females. Pancreas, crop content, crop tissue and blood samples were taken from male chicks every 3 days. The same samples were taken from females every 3 days until the 12th day, and from the 12th day to the 42nd day samples were taken every 9 days. Some 16 chicks were used in each trial. The blood samples were centrifuged instantly and their plasma separated. Tissue and content samples were homogenized and centrifuged and their supernatants obtained. The a-amylase activity was determined in plasma and supernatant samples. In addition to changes in the a-amylase activity of the pancreas, plasma and crop content, an increase was determined related to age. When the total activities were measured, the increase in a-amylase activity was observed clearly. Low levels of a-amylase activity were determined in crop tissue. A high correlation was found between a-amylase activities of the pancreas and plasma. Although there was no difference in a-amylase activity between males and females, the total pancreatic a-amylase activity of males on days 12, 21 and 39 was found to be significantly higher than that of the females. It was considered that, like in mammalians, most a-amylase in the digestive tract originates from the pancreas in chicks, the activity of the crop is very important in starch digestion, and the activity of the content may originate from a source outside of the crop. Although sex does not affect the level of the enzyme, it was concluded that males can digest starch more efficiently than females because of the difference in pancreatic total a-amylase activity.

Changes in a-amylase activity of the pancreas, plasma, crop tissue and crop content related to age and sex were determined in chicks and the correlation among the pancreas, plasma, crop tissue and crop content were investigated. A total of 336 ISA- 5 broiler hybrid chicks were used as material. The chicks were separated into two groups: 224 males and 112 females. Pancreas, crop content, crop tissue and blood samples were taken from male chicks every 3 days. The same samples were taken from females every 3 days until the 12th day, and from the 12th day to the 42nd day samples were taken every 9 days. Some 16 chicks were used in each trial. The blood samples were centrifuged instantly and their plasma separated. Tissue and content samples were homogenized and centrifuged and their supernatants obtained. The a-amylase activity was determined in plasma and supernatant samples. In addition to changes in the a-amylase activity of the pancreas, plasma and crop content, an increase was determined related to age. When the total activities were measured, the increase in a-amylase activity was observed clearly. Low levels of a-amylase activity were determined in crop tissue. A high correlation was found between a-amylase activities of the pancreas and plasma. Although there was no difference in a-amylase activity between males and females, the total pancreatic a-amylase activity of males on days 12, 21 and 39 was found to be significantly higher than that of the females. It was considered that, like in mammalians, most a-amylase in the digestive tract originates from the pancreas in chicks, the activity of the crop is very important in starch digestion, and the activity of the content may originate from a source outside of the crop. Although sex does not affect the level of the enzyme, it was concluded that males can digest starch more efficiently than females because of the difference in pancreatic total a-amylase activity.