Open Access Volume 4 • Issue 5 • 1000188 J Aquac Res Development ISSN: 2155-9546 JARD, an open access journal Research Article Open Access Cuong et al., J Aquac Res Development 2013, 4:5 http://dx.doi.org/10.4172/2155-9546.1000188 Research Article Open Access Aquaculture Research & Development Keywords: Copra; Mannooligosaccharides; Prebiotics; Litopenaeus vannamei; Growth; Intestine bacteria; Disease resistance Introduction Whiteleg shrimp, Litopenaeus vannamei, is among high commercial value aquatic species being cultured recently worldwide [1]. However, because of the rapid development, coupled with unusual climate change, the shrimp farming has severely sufered signiicant economic losses due to viruses and vibriosis diseases [2-4]. Traditional uses of antibiotics for shrimp disease control have been criticized due to the potential development of multi-antibiotic resistance of pathogenic bacteria, reduction in the eicacy of antibiotic treatments, residue accumulation in tissues, and immunosuppression [5-9]. herefore, using probiotics, prebiotics, and medicinal plants as preventive, environment-friendly and economically eicient alternatives to antibiotic in shrimp farming has been received heightened attention in recent years [10-13]. "Prebiotics are deined as nondigestible food ingredients that beneicially afect the host by selectively stimulating the growth of and/ or activating the metabolism of one or a limited number of health- promoting bacteria in the intestinal tract, and thus improve host health" [14]. It have been reported that fructooligosaccharides, inulin, and isomaltooligosaccharides showed the prebiotic characteristic in whiteleg shrimp [15-18]. MOS is basically constituted by linear chains of mannose. Several commercial products of MOS were in trade with various purities and they difer in their molecular structure, depending on the source and processing conditions. he MOS recently used to cultivate shrimps was extracted from yeast cell-wall and it consists of the chain of mannose residues linked together via α-1, 6-glycosidic bond [12,19,20]. Another kind of MOS is β-1, 4-mannooligosaccharides (β-MOS) produced by enzymatic hydrolysis of plant mannans via β-mannanases [21]. his β-MOS is generally purer and shows excellent prebiotic eicacy on humans and terrestrial animals at low doses. However, as for aquatic animals, there is little known about the efectiveness of any β-mannooligosaccharides at present. he aim of this study was to evaluate the efects of copra MOS on growth, survival, intestinal microflora, and bacterial pathogen resistance of whiteleg shrimp. Materials and Methods Copra MOS and diet preparation he prebiotic used in this study, mannooligosaccharides, was produced by partial enzymatic hydrolysis of copra pulp residues obtained from coconut oil processing facilities using a recombinant β-mannanase (from Aspergillus niger BK01) [21]. he minimum level of mannooligosaccharides was 90% ww -1 . he copra MOS powder was free of antibiotics (tetracycline, chloramphenicol, and chlortetracycline), alatoxin B1 and bacterial pathogens (Vibrio cholera, Vibrio parahaemolyticus, Salmonella, E. coli). Five diets (control, MOS4, MOS6, MOS8 and MOS10) were formulated with supplementation of various amounts of copra MOS (0, 4, 6, 8, or 10 g) in 1 kg of dried feed. Copra MOS supplied in the powder form was diluted in an adhesive and feed attractant oil (squid liver oil, *Corresponding author: Dang Thi Thu, School of Biotechnology and Food Technology, Hanoi University of Science and Technology, 1 Dai Co Viet, Hanoi, Vietnam; E-mail: dangthudhbk@yahoo.com Received May 27, 2013; Accepted July 22, 2013; Published July 24, 2013 Citation: Cuong DB, Dung VK, Hien NTT, Thu DT (2013) Prebiotic Evaluation of Copra-Derived Mannooligosaccharides in White-Leg Shrimps. J Aquac Res Development 4: 188 doi:10.4172/2155-9546.1000188 Copyright: © 2013 Cuong DB, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract β-Mannooligosaccharides, produced by partial enzymatic hydrolysis of copra pulp residues using recombinant A. niger β-mannanase, were evaluated for its potential use as a prebiotic feed supplement for L. vannamei culture. Results observed in a 30-day feeding trial showed that dietary supplementation of copra-derived MOS, with doses varying from 4 to 10 g kg -1 of dried feed, increased the number of intestinal Lactobacilli and Biidobacteria in shrimps fed copra-MOS supplemented diets increased approximately from 150-300%. The number of intestinal presumptive Vibrio, Coliforms, Clostridia and Salmonella reduced to 39.6-54.1%, 56.9-65.9%, 71.8-86.1% and 100- 100%, respectively. In addition, copra-MOS supplement in the feed led to an enhancement of the weight gain, speciic growth rate, feed conversion ratio and feed intake of shrimps (P<0.05). After a 7-day challenging test with Vibrio harveyi pathogen (~10 6 CFU mL -1 ) by immersion, the cumulative mortality of the shrimps fed with the diet supplemented 10 g kg -1 copra-MOS was 3.5%, that obviously decreased compared to the control shrimps (29.5% mortality). Taking advantage of its intestinal microlora modulation towards increasing probiotic-like bacteria and Vibriosis resistance, this cheap oligosaccharide will be valuable in various aquatic animal farming. Prebiotic Evaluation of Copra-Derived Mannooligosaccharides in White- Leg Shrimps Do Bien Cuong 1 , Vu Kim Dung 2 , Nguyen Thi Thu Hien 3 and Dang Thi Thu 1 * 1 School of Biotechnology and Food Technology, Hanoi University of Science and Technology, 1 Dai Co Viet, Hanoi, Vietnam 2 Breeding and Biotechnology Center, Vietnam Forestry University, Hanoi, Vietnam 3 National Broodstock Center for Mariculture Species in Northern Vietnam. (NACMAN), Research Institute for Aquaculture No 1, Hai Thanh, Duong Kinh, Haiphong, Vietnam Defatted copra meal's carbohydrates is abundant agricultural waste which is discharged by coconut industries. Balasubrtamaniam [22] found that content of copra meal was 23% of mannans and 61% galactomannans. his material is very popular in Vietnam to produce MOS [21].