Dietary Supplementation of humic acid in the Feed of juvenile asian seabass, Lates calcarifer to counteract possible negative effects of Cadmium Accumulation on Growth and Fish Well-being when Green Mussel (Perna viridis) is used as a Feed ingredient.

摘要

The present study purposed to determine the dietary humic acid supplementation in the feed juvenile Asian seabass, Lates calcarifer, to counteract possible negative effects of cadmium (Cd) accumulation on growth and fish well-being when green mussel (Perna viridis) is used as a feed ingredient. The experiment design used completely random design (CRD) with four treatments: humic acid supplementation difference in diets (0, 800, 1600 or 2400 mg kg(-1)), with three replications. The Asian seabass juveniles (initial weight of 4.19 +/- 0.60 g) were stocked in aquariums (80 x 35 x 28 cm), with each initially 25 fish. The fish were fed the experimental diets containing isoprotein and Cd of 0.12 mg kg(-1) for 70 days of cultivation. The result showed that the diet's humic acid supplementation could prevent the Cd in fish liver, kidney and meat and improve growth compared with a fish-fed diet without humic acid. Supplementation of humic acid starting at 800 mg kg(-1) to the diet, Cd accumulation in fish meat not detected (<0.005 mg kg(-1)). The growth responses were highest in the fish fed the diet supplemented humic acid at 1600 mg kg(-1). In concomitant with growth pattern, dietary treatments improved the feed digestibility, metabolic enzyme, blood chemistry and bone calcium. Thus, the present study concludes that dietary humic acid supplementation could counteract Cd accumulation's harmful effects on fish growth. Humic acid at 1600 mg kg(-1) feed was the optimum dosage to increase Asian seabass growth on a feed from the green mussel as a feed ingredient.