Abstract: Mugilogobius chulae is a small euryhaline or estuarine goby recently proposed as an ideal species for use in ocean environmental toxicology studies. However, the nutritional requirements of M. chulae remain unknown. Eight experimental diets at one of four protein levels (35%, 40%, 45%, or 50%) and two lipid levels (5% or 10%) were formulated to investigate the effects of differing dietary protein and lipid levels on the growth performance, body composition and liver morphological condition of M. chulae. Juvenile gobies (1760 individuals, 0.011±0.001 g fish-1) were randomly allotted to 32 tanks (four replicates of each of the eight treatments) and fed twice a day for 9 weeks. Weight gain (WG) and specific growth rate (SGR) increased significantly with increasing dietary protein from 35% to 45% (P< 0.05), and further increases, from 45% to 50%, caused a decline in both of these values. However, WG and SGR were not affected by dietary lipid concentration (P> 0.05). Whole-body crude lipid and linoleic acid (C18:2n-6) contents in juvenile M. chulae increased significantly with increasing dietary lipid content (P< 0.05). Although hepatosomatic index (HSI) and viscerosomatic index (VSI) did not increased significantly with increasing dietary lipid content (P>0.05), and no pathological changes were observed in the liver, lipase activity significantly decreased (P < 0.05). The dietary protein level driving optimal WG and SGR also led to the highest trypsase activity. Thus, 45% crude protein and 5% lipidis sufficient to ensure good growth performance in juvenile M. chulae, and this diet appears to have no substantial adverse effects.Abstract: Mugilogobius chulae is a small euryhaline or estuarine goby recently proposed as an ideal species for use in ocean environmental toxicology studies. However, the nutritional requirements of M. chulae remain unknown. Eight experimental diets at one of four protein levels (35%, 40%, 45%, or 50%) and two lipid levels (5% or 10%) were formulated to inv...Show More
