Feeding marbled spinefoot rabbitfish (Siganus rivulatus) juveniles with β‐mannanase enzyme: An effective tool to enhance growth and immunity and induce low salinity tolerance. (1st September 2020)

• Record Type: Journal Article
• Authors: Sallam, Ahmed E.; Almisherfi, Hebatollah M.; El‐Feky, Mohamed M. M.; Abdel‐Ghany, Heba M.; Salem, Mohamed El‐S.
• Is Part Of: Aquaculture nutrition. Volume 26:Number 6(2020)
• Page Start: 1884
• Page End: 1894
• Publication Date: 2020-09-01
• Subjects: β‐mannanase -- growth -- intestinal morphology -- non‐specific immunity -- salinity stress -- Siganus rivulatus; Aquaculture -- Periodicals; Aquatic animals -- Feeding and feeds -- Periodicals; Fishes -- Feeding and feeds -- Periodicals; 639.3
• DOI: 10.1111/anu.13145
• Languages: English
• ISSNs: 1353-5773

Abstract

Abstract: This experiment was conducted to evaluate the effects of a commercial dietary β‐mannanase enzyme on growth performance, immunity, gut integrity and salinity tolerance of spinefoot rabbitfish ( Siganus rivulatus ) juveniles fed soybean‐based diets. A basal diet (protein, 400 g/kg; gross energy, 20 MJ/kg) was supplemented with 0.0 (control), 0.2, 0.5 or 0.8 g β‐mannanase/kg to formulate four experimental diets. Each treatment contained three net cages with 50 fish per net. The experiment lasted for 8 weeks. The results revealed that all β‐mannanase levels have significantly improved the growth performance compared with the control. β‐mannanase addition at 0.5 g/kg diet showed the best results of the growth performance, survival rate and feed utilization efficiency. The results also indicated that β‐mannanase supplementation improved protease, lysozyme, esterase, immunoglobulin and alkaline phosphatase activities and decreased alanine aminotransferase and aspartate aminotransferase activities compared with the control. Moreover, the dietary β‐mannanase supplementation significantly improved intestinal morphology by increasing the muscle thickness and villi length. Salinity challenge showed that β‐mannanase supplementation at 0.2 and 0.5 g/kg diet significantly increased fish survival compared with 0.8 and 0.0 g/kg diet. In conclusion, β‐mannanase inclusion in S . rivulatus diets improved growth performance, feed utilization, non‐specific immunity, intestinal morphology and fish quality. The recommended level of mannanase inclusion in S. rivulatus diets is 0.5 g/kg diet.