Croatian Journal of Fisheries (Sep 2001)
A STUDY ON THE GROWTH POTENTIAL OF GILTHEAD SEA BREAM HELD IN A COMMERCIAL RECIRCULATION SYSTEM AND TREATED WITH A BY-PRODUCT FROM THE INDUSTRIAL PRODUCTION OF BOVINE GROWTH HORMONE
Abstract
Gilthead sea bream, maintained in a commercial scale recirculation system, were subjected to three injections (0,5 and 10 µg -1 body weight) with a by-product from the industrial production of recombinant bovine growth hormone (rbGH). Injections were provided at experiment start and at 3 and 6 weeks. Growth performance of animals was evaluated over a period of 8 weeks (n = 171 per treatment). At trial end fish were examined for proximate composition, fillet yield and visceral indices. No differences were recorded in individual growth performance between the three treatment groups (P > 0.05). Examination of protein productive value and protein efficiency ratio indicated approximately 20% of dietary protein was incorporated into animals irrespective of treatment. However incorporation of dietary lipid decreased with increasing dose of rbGH. High dose GH decreased liver weight (P < 0.05) when compared to control fish, with a concomitant reduction in hepatosomatic index (P < 0.05). Fillet weight and yield was higher in animals treated with 10 µg -1 body weight dose when compared to low dose rbGH injected fish (P < 0.05).
