Dietary supplementation with xylanase-expressing B. amyloliquefaciens R8 improves growth performance and enhances immunity against Aeromonas hydrophila in Nile tilapia (Oreochromis niloticus).
Bacillus amyloliquefaciens has attracted attention as a probiotic in aquaculture due to its immunostimulatory activity against pathogenic infection. Xylanases are extensively used in animal feed to degrade plant ingredients, enhancing nutrient utilization and increasing the growth rate of various animals. In the present study, the effects of dietary supplementation with B. amyloliquefaciens and xylanase-expressing B. amyloliquefaciens R8 on the growth of Nile tilapia (Oreochromis niloticus) and immunity against Aeromonas hydrophila were evaluated. The results showed that the xylanase activity in the intestine, weight gain (WG), feed efficiency (FE) and condition factor (CF) of Nile tilapia fed B. amyloliquefaciens R8 for 2 months were significantly increased compared with those of the fish fed the control diet and B. amyloliquefaciens. Moreover, the mRNA expression of growth- and metabolism-related genes, such as insulin-like growth factor-1 (igf-1), glucokinase (GK), glucose-6-phosphate 1-dehydrogenase (G6PD), and glucose-6-phosphatase (G6Pase), was significantly induced in Nile tilapia fed administered B. amyloliquefaciens R8, and this group also exhibited a higher survival rate than the control fish following a challenge with A. hydrophila. The phagocytic activity and respiratory burst activity of head kidney leukocytes as well as the serum lysozyme activity of B. amyloliquefaciens R8-fed Nile tilapia were significantly higher than those of fish fed the control diet for 2 months. Superoxide dismutase (SOD) levels in the head kidney leukocytes of Nile tilapia fed B. amyloliquefaciens R8 differed from those of fish fed the control diet, but this was not significant. These results indicate that dietary supplementation with xylanase-expressing B. amyloliquefaciens R8 improves growth performance and enhances immunity and disease resistance against A. hydrophila in Nile tilapia.
Department of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan; Department of Aquaculture, Faculty of Fisheries and Marine Science, University of Brawijaya, Indonesia.
Febriyansyah
F
Saputra
Department of Aquaculture, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan.
Ya-Li
YL
Shiu
Department of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan.
Yo-Chia
YC
Chen
Department of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan; Department of Aquaculture, Faculty of Fisheries and Marine Science, University of Brawijaya, Indonesia.
Asthervina Widyastami
AW
Puspitasari
Department of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan; Department of Aquaculture, Faculty of Fisheries and Marine Science, University of Brawijaya, Indonesia.
Ridha Handriany
RH
Danata
Department of Aquaculture, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan.
Chun-Hung
CH
Liu
Department of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan. Electronic address: syhu@mail.npust.edu.tw.
Shao-Yang
SY
Hu
D016980:Aeromonas hydrophila / Q000502:physiology*; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D023681:Cichlids / Q000254:growth & development; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements; D060467:Disease Resistance; D043364:Endo-1,4-beta Xylanases / Q000378:metabolism; D005393:Fish Diseases / Q000276:immunology* / Q000382:microbiology; D016905:Gram-Negative Bacterial Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D019936:Probiotics
D043364:Endo-1,4-beta Xylanases
Bacillus amyloliquefaciens; Growth; Innate immunity; Oreochromis niloticus; Xylanase