THE CORRELATIONS BETWEEN STANDARD METABOLIC RATE AND GROWTH PERFORMANCE IN JUVENILE GOLD FISH

The current study investigated the relationship between standard metabolic rate (SMR) and growth performance using 30 gold fish (Carassius auratus) under the laboratory conditions at (25.00.5). All individuals were raised in a man-made laboratory experimental tank for the whole experiment with a 2 weeks feeding and followed by 2 weeks fasting. During feeding stage, each fish was fed twice daily (9:00 and 15:00) and food cunsumption by fish was recorded. Two week feeding greatly increased the body mass, body length and SMR, whereas starvation decreased the body mass and SMR without impacting body length (P0.05). This fish species had similar and stable SMR in feeding period and starvation period (both P0.05). The SMR1 (at the beginning of feeding experiment) was not correlated with the feeding rate (FR), feeding efficiency (FE) and specific growth rate (SGRBM) of the body mass (P0.05). SMR2 at the end of feeding experiment was associated with the FR but not FE and SGRBM. Feeding increased body mass and fasting decreased the body mass. The theoretic rate of daily increased body mass during the feeding period was not significantly differ from that of daily decreased body mass during the starvation period (P0.05) based on the analysis of covariance. The specific growth rate in SMR (SGRSMR) during the feeding experiment, not SGRBM, was correlated negatively with that of the starvation experiment. These results suggest the stable SMR and absolute growth rate of individuals of the juvenile gold fish under the laboratory conditions, but, the SMR of this fish species acclimated at the laboratory surrounding could not predict the adaptive characteristics of growth performance and hence their fitness.