STUDIES ON THE MORPHOLOGY,FEEDING HABIT AND GROWTH OF CATLA CATLA

This paper describes the morphology and changes in the major measurable characters and their ratios in 1—3 year-old Catla carla.1—3 year-old fish feed chiefly on artificial food,they also eat a large part of plankton.The taxes and ratios of plankton have been analysed.There existed a linear correlation between intestine length(Y)and body length(X): Y=6.38X-89.95. Relative growth rates and growth index in body length and body weight decreased gradually with increases in age over the range of 1—4 years.The relationship between body length(L)and body weight(W)was:W=0.00002261L3.0669.The characters of growth were analysed using Von.Bertalanffy growth equation.The estimated parameters were:L∞=821.2 mm;W∞=19616.6g;t0=0.6year;k=0.3.There was no turning point in the growth of body length.The growth rate decreased gradually with increased age.In the growth of body weight, a turning point was found at the age of 4.3 years,at which the weight growth rate reached the maximum.The fish exhibited rapid weight growth before the age of 4.3 years;afterwords, weight growth slowed down.