DETERMINING THE POTENTIAL OF COMPENSATORY GROWTH OF NILE TILAPIA (OREOCHROMIS NILOTICUS, LINNAEUS, 1758) IN A RECIRCULATING AQUACULTURE SYSTEM

Catalina (Ciortan) Mirea, V. Cristea, Lorena Dediu, Mirela (Cretu) Mocanu, Desimira Maria (Stroe) Dicu, St.M. Petrea

Abstract
The effect of feed cycling on compensatory growth was examined in Nile tilapia (83 g), held individually at 28ºC. Fish were fasted for 2, 4, and 6 days and then refed the same period like they were fasting with the same daily quantity of food like the controls. In all the variants we had applied the same feed rate, 1.6% BW. The fed was administrated 2 times daily. After 25 days, fish fasted for 6 days at a time were not significantly smaller than controls, or fish experiencing 2 or 4 days of fasting. There were no significantly differences in visceral fat or hepatosomatic indices. Fish subjected to fasting displayed compensatory growth, and high growth rate during the recovery phase was achieved by hyperphagia, rather than improved feed conversion. There was a highly significant relationship between feed intake and weight gain, and feed conversion differ between fish subjected to the different treatments,with good result in the second treatment were the period of fasting was only for 2 days. The results indicate that Nile tilapia can be subjected to short periods of fasting without significant effects on growth, and for a good improvement in feed utilization during the refeeding period.

Key words: compensatory growth, Nile tilapia, refeeding period