Enhancing growth and non-specific immunity of grass carp and Nile tilapia by incorporating Chinese herbs (Astragalus membranaceus and Lycium barbarum) into food waste based pellets. (December 2016)

• Record Type: Journal Article
• Authors: Mo, Wing Yin; Lun, Clare Hau In; Choi, Wai Ming; Man, Yu Bon; Wong, Ming Hung
• Is Part Of: Environmental pollution. Volume 219(2016)
• Page Start: 475
• Page End: 482
• Publication Date: 2016-12
• Subjects: Antimicrobial agents -- Chinese medicinal herbs -- Food waste based pellets -- Growth promotors; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2016.05.055
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: The effects of Astragalus membranaceus and Lycium barbarum on the growth performance and non-specific immunity of grass carp and Nile tilapia were studied. Herb extracts of Chinese medicinal herbs (2 g kg −1 or 20 g kg −1 ) were incorporated into food waste based fish feed pellets. Fish growth and selected non-specific immune parameters of grass carp and Nile tilapia were studied in two separate feeding trials. Both grass carp and Nile tilapia fed diets of feed pellets containing 2 g kg −1 Lycium barbarum extract achieved the best relative weight gain, feed conversion ratio, specific growth rate and protein efficiency ratio among all experimental diets. Fish fed with diets containing 2 g kg −1 Lycium barbarum also resulted in significantly higher total immunoglobin, bactericidal activity and anti-protease activity; and also a lower mortality when challenged with pathogenic bacteria. On the other hand, both fish species fed with diets containing 20 g kg −1 of Astragalus membranaceus and 20 g kg −1 Lycium barbarum, resulted in significantly impaired weight gain. In addition, incorporation of 2 g kg −1 Lycium barbarum extract would be a more suitable dose for both fish species, in terms of achieving better feed conversion ratio, specific growth rate, protein digestibility, and improved non-specific immune parameters. Based on this study, it can be concluded that waste based feed pellets incorporated with Chinese medicinal herb extracts have the ability to enhance growth and immunity of fish. Therefore, the use of Chinese medicinal herbs in aquaculture should be encouraged, in order to replace certain antibiotics known to impose environmental and health effects through the discharge of aquaculture effluents. Highlights: Extract of the Chinese herbs studied could enhance fish non-specific immunity. 2 g kg −1 Lycium barbarum extract could also enhance fish growth. Fish fed with diets with 2 g kg −1 extract are more resistant to bacterial challenge. Abstract : Incorporating extracts of Chinese herb into fish feed pellets as a potential alternative to antibiotics for enhancing fish growth and/or non-specific immunity.