文献类型：期刊文献

英文题名：Effects of dietary chitosan and Bacillus subtilis on the growth performance, non-specific immunity and disease resistance of cobia, Rachycentron canadum

作者：Geng X.; Dong X.-H.; Tan B.-P.; Yang Q.-H.; Chi S.-Y.; Liu H.-Y.; Liu X.-Q.

机构：[1]Laboratory of Aquatic Animal Nutrition and Feed, College of Fisheries, Guangdong Ocean University, Zhanjiang, Guangdong 524025, 40 Jiefang Road, China

年份：2011

卷号：31

期号：3

起止页码：400

外文期刊名：Fish and Shellfish Immunology

收录：Scopus(收录号：2-s2.0-79960639202)

语种：英文

外文关键词：Bacillus subtilis; Chitosan; Growth; Immunity; Rachycentron canadum; Vibrio harveyi

外文摘要：The present study was performed to investigate the effects of various levels of dietary Bacillus subtilis and chitosan on the growth performance, non-specific immunity and protection against Vibrio harveyi infection in cobia, Rachycentron canadum. Fish were fed with the control diet and six different experimental diets containing three graded levels of B. subtilis at 2 × 1010 CFU g-1 (0.0, 1.0, 2.0 g kg-1 diet) for each of two levels of chitosan (3.0 and 6.0 g kg-1 diet). The results of 8 weeks feeding trial showed that the survival rate ranged from 81.3% to 84.0% with no significant difference (P > 0.05). The SGR (%) in the fish fed with dietary treatments was significantly higher than that of the control fish except diet 6 group with 2.0 g kg-1 B. subtilis and 3.0 g kg-1 chitosan. The serum lysozyme activities were significantly higher in 6.0 g kg-1 chitosan groups and no significant differences were observed among B. subtilis levels. The serum ACP activities were significantly higher in 3.0 g kg-1 chitosan groups at 0.0 and 1.0 g kg-1 B. subtilis levels; at low chitosan level, the cobia fed diets with 1.0 g kg-1 B. subtilis had significantly higher serum ACP activity, but at high chitosan level, the cobia fed diets with 2.0 g kg-1 B. subtilis had significantly higher serum ACP activity. The phagocytosis and respiratory burst activity in the fish fed with dietary treatments was significantly higher than that of the control fish except diet 3 group with 6.0 g kg-1 chitosan. Moreover, fish fed the diet containing 2.0 g kg-1 B. subtilis and 6.0 g kg-1 chitosan had significantly higher post-challenge survival on the 7th day following V. harveyi infection and post-challenge survival showed clearly the synergistic effect of chitosan and B. subtilis. Based on these results, the combination of 1.0 g kg-1 B. subtilis and 6.0 g kg-1 chitosan is optimal for the growth, innate immunity and disease resistance of cobia with an 8-week oral administration. ? 2011 Elsevier Ltd.