An experiment was conducted to determine the activities of aspartate aminotransferase and alanine aminotransferase and the liver biometry of laying quails (Coturnix coturnix japonica) from one to 25 days of age. Ninety, day-old, quails were used. A randomized complete experimental design was used with six ages, five replicates and one animal per experimental unit. At 1, 5, 10, 15, 20 and 25 days of age five animals were sacrificed, the liver removed, weighed, frozen with liquid nitrogen and stored at -20 ºC. Liver samples were collected, homogenized and centrifuged to determine the homogenate aspartate aminotransferase and alanine aminotransferase activities. Liver weight developed linearly with age but differently from the body weight. Total aspartate aminotransferase and alanine aminotransferase activities showed a linear increase with age. Total aspartate aminotransferase showed higher activities than alanine aminotransferase. At one day old, quail liver aspartate aminotransferase and alanine aminotransferase had specific activities higher than those observed at other ages. Aspartate aminotransferase activity per g of liver was higher than aspartate aminotransferase at all ages studied. Alanine aminotransferase activity per g of body weight showed a linear reduction with age. The data observed will allow better adjustment of the level of protein in quail feed.
enzymatic profile; metabolism; transaminases
