Abstract
The objectives of the study were to determine the chemical constituents of rainbow trout during the first 14 months of life, to study the effects of starvation on the body composition of trout, and to measure organ wts during the first 14 months o life. Body fat and protein content as a percentage of body wt increased with age, the water content declined and the ash content remained constant during the first 14 months of life. There were no significant differences in body composition between immature male and female rainbow trout. Total body ions as a proportion of ash content decreased until the 10th moth and their began to increase. During starvation, fat was used as the primary source of energy while water and ash content increased and protein content remained constant as a percentage of body wt. The gall bladder, liver, and air bladder remained relatively constant as a percentage of body wt during the 1st yr of life. As body wt increased, the relative wt of brain, heart, and digestive system decreased while the gonad and spleen wt increased.