전복용 배합사료의 어분 대체 단백질원 및 사료첨가제 효과

Abstract

Abstract

Substitution-effect of animal and plant protein sources for fishmeal in diet for juvenile abalone (Haliotis discus hannai), and effect of dietary additive on growth and tolerance of abalone against the stresses were determined in the 16-week feeding trials in the experiments Ⅰ and Ⅱ, respectively. In the experiment Ⅰ, fifty juvenile (an initial body weight of 10.0 g) abalone per container were randomly distributed into 27, 50 L plastic rectangular containers. Nine experimental diets with triplicates were prepared. Fishmeal was used as sole protein source (Con). Animal protein sources [poultry meal (PM), meat and bone meal (MB), Silkworm pupae meal (SPM)] and plant protein sources [soybean meal (SM) and corn gluten meal (CM)] were substituted fishmeal in the diet. Besides, their combined substitution of animal and/or plant protein sources [soybean meal and corn gluten meal (SM+CM), soybean meal and silkworm pupae meal (SM+SPM) and corn gluten meal and silkworm pupae meal (CM+SPM)]. Survival of abalone fed the SM and SM+SPM diets was significantly (P<0.05) higher than that of abalone fed the CM, SPM, MB and CM+SPM diets, but not significantly (P>0.05) different from that of fish fed the Con diet. Weight gain of abalone fed the SM+SPM and SM+CM diets was significantly (P<0.05) higher than that of abalone fed the Con diet. Shell length of abalone fed the SM+CM and SM+SPM diets was significantly (P<0.05) higher than that of abalone fed the Con diet. The rate of carcass weight to total weight of abalone fed the SM+CM diet was significantly (P<0.05) higher than that of abalone fed the Con diet. Chemical composition of carcass of abalone except for ash was significantly (P<0.05) affected by the experimental diet. In the experiment Ⅱ, seventy juvenile (an initial body weight of 4.2 g) abalone per container were randomly distributed into 21, 50 L plastic rectangular containers each. The various sources of additives were included into the experimental diets

control diet (Con) with no additive, by-product of green tea (BPG), extract of figs (EF), extract of green tea (EG), commercially available product of Hearok (PH), and Haematococcus (HC). Finally, dry sea tangle (ST) was prepared to compare the efficiency of the experimental diets. Fishmeal, soybean meal and shrimp head meal were used as the protein source, and dextrin, sea tangle powder and wheat flour, and soybean oil and fish oil were used as the carbohydrate and lipid sources, respectively in the experimental diets. At the end of the 16-week feeding trial, abalone was exposed to the different types of stresses (air exposure, and sudden changes of temperature and salinity) and the accumulated mortality of abalone was monitored as the scheduled intervals. Survival of abalone fed the ST was highest. However, weight gain of abalone fed the EF, EG and PH diets was significantly (P<0.05) higher than that of abalone fed the BPG diet or ST. Shell length of abalone fed the all experimental diets was significantly (P<0.05) higher than that of abalone fed the ST. Accumulated mortality of abalone fed the ST was low when exposed to the different types of stresses. Also, relatively low mortality was achieved in abalone fed the HC and EF diets. In considering these results, it can be concluded that a combination of soybean meal and corn gluten meal (SM+CM) or combination of soybean meal and silkworm pupae meal (SM+SPM) could be considered the most proper substitution protein source for fish meal in the diet for abalone. In addition, dietary inclusion of Haematococcus (HC) and extract of figs (EF) seemed to be effective to lower mortality of abalone when exposed to air or sudden changes in salinity among additives tested in this study.