文献类型：期刊文献

英文题名：The efficiency of indigenous isolates Bacillus sp. RCS1 and Bacillus cereus RCS3 on growth performance, blood biochemical indices and resistance against Vibrio harveyi in cobia fish (Rachycentron canadum) juveniles

作者：Amenyogbe, Eric[1];Zhang, Jian-dong[1,2];Huang, Jian-sheng[1,2];Chen, Gang[1,2]

机构：[1]Guangdong Ocean Univ, Fishery Coll, Zhanjiang 524025, Peoples R China;[2]Guangdong Prov Key Lab Pathogen Biol & Epidemiol, Zhanjiang 524088, Peoples R China

年份：2022

卷号：25

外文期刊名：AQUACULTURE REPORTS

收录：SCI-EXPANDED(收录号：WOS:000862245300001)、、WOS

语种：英文

外文关键词：Rachycentron canadum; Indigenous strains; Digestive enzyme activity; Antioxidant enzyme activity

外文摘要：In this study, cobia (Rachycentron canadum) juveniles were utilised as an aquatic model to explore growth performance and immune indices after 70 days of feeding with supplementation of viable isolated microbes' concentrations of 1 x 10(10) and 1 x 10(12) CFU/mL indigenous isolates Bacillus sp. RCS1 and Bacillus cereus strain RCS3, respectively. Regarding growth performance, fish provided with the indigenous isolates exhibited a significant (P < 0.05) enhancement. The hematological indices such as red blood cells, white blood cells, corpuscular haemoglobin concentration, mean corpuscular volume, haemoglobin, and Mean corpuscular haemoglobin were all increased (P < 0.05) in the juvenile cobia fed with indigenous isolates Bacillus sp. RCS1 and B. cereus RCS3 as a nutritional supplement. This study also significantly differed in serum analysis (albumin, globulin, lysozyme, total protein) between all the treatments with the Bacillus sp. RCS1 1 x 10(10) proven to be the best. In the present study, the expression of myostatin and insulin-like growth factor 2 showed no significant change (P > 0.05) among the treatment and control groups tested; nonetheless, their mRNA expression exhibited variations in all trial groups. The present study showed significant differences (P < 0.05) among groups in the case of insulin-like growth factor 1, peroxisome proliferator-activated receptors. The improved antioxidant enzyme activities of catalase (CAT) and superoxide dismutase (SOD) digestive enzyme activities (amylase, trypsin, pepsin, lipase, and cellulose) may be linked to the enhanced resistance of fish against Vibrio harveyi infection. The enhanced activities of digestive enzymes in indigenous isolates treatments could be linked to the improved digestion and enhanced food absorption that ultimately helps enhance feed utilisation and growth performance. The results showed that indigenous isolates addition to a commercial diet, had the prospective to enhance cobia juveniles' growth and immune response regardless of their dosage.