Aquaculture 495 (2018) 786–793 Contents lists available at ScienceDirect Aquaculture journal homepage: www.elsevier.com/locate/aquaculture Effects of corncob derived xylooligosaccharide on innate immune response, disease resistance, and growth performance in Nile tilapia (Oreochromis T niloticus) fingerlings Hien Van Doana, Seyed Hossein Hoseinifarb, Caterina Faggioc, Chanagun Chitmanatd, ⁎ Nguyen Thi Maie, Sanchai Jaturasithaa, Einar Ringøf, a Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai 50200, Thailand b Department of Fisheries Gorgan, University of Agricultural Sciences and Natural Resources, Gorgan, Iran c Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina Viale Ferdinando Stagno d'Alcontres, 31 98166, S. Agata, Messina, Italy d Faculty of Fisheries Technology and Aquatic Resources, Maejo University, Chiang Mai 50290, Thailand e Department of Aquaculture, Faculty of Fisheries, Vietnam National University of Agriculture, Hanoi, Viet Nam f Norwegian College of Fishery Science, Faculty of Bioscience, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway. ARTICLE INFO ABSTRACT Keywords: An-eight week experiment was conducted to test efficacy of corncob derived xylooligosaccharides (CDXOS) on Corncob mucosal and serum immune, disease resistance, and growth performance of Nile tilapia (Oreochromis niloticus). Xylooligosaccharide Three hundred and twenty tilapia fingerlings (20.72 ± 0.02 g) were fed the following diets; 0 (Diet 1- control), − Nile tilapia added 5 – (Diet 2), 10 – (Diet 3), and 20 g kg 1 CDXOS (Diet 4). After 4 and 8 weeks feeding were mucosal, Growth performance serum immune responses, and growth performance measured. A challenge test (15 days) against Streptococcus Mucosal immune parameters agalactiae was conducted after 8 weeks post-feeding. A significant (P < 0.05) stimulation of skin mucus lyso- Serum immunology zyme and peroxidase activities, as well as serum immune parameters (serum lysozyme, serum peroxidase, al- ternative complement activities, phagocytosis index, and respiratory burst activity) was noticed by feeding the fish CDXOS supplemented diets compared to the control group. Highest (P < 0.05) innate immune parameters − were observed by feeding the fish 10 g kg 1 CDXOS vs. the other treatments. With regard to the challenge test, relative percent survival (RSP) of Nile tilapia fingerlings fed Diet 2, Diet 3, and Diet 4 was 34.78%, 60.87%, and − 30.43%, respectively. Among the supplemented groups, dietary inclusion of 10 g kg 1 CDXOS revealed sig- nificant (P < 0.05) higher RPS and resistance towards S. agalactiae than the other groups. Regarding growth performance, final weight, weight gain, specific growth rate, and feed conversion ratio were remarkably − (P < 0.05) improved in the CDXOS groups; highest improvement was observed in the 10 g kg 1 CDXOS − treatment. In conclusion, inclusion of 10 g kg 1 CDXOS derived from corncob improved growth performance and health status of Nile tilapia fingerlings. 1. Introduction delivery methods, and side effects to human and the environment (Done et al., 2015; Murray and Peeler, 2005). Thus, it was necessary to Global aquaculture has dramatically expended during the last develop cost-effective alternatives to sustain environmentally friendly decade, and contributed for > 50% of the total fisheries production in aquaculture (Turcios and Papenbrock, 2014), and in this respect has 2014 (Makled et al., 2017). Expansion and intensification of tilapias, prebiotics received considerable attention as a promising alternative one of the most important farmed fish species in the world are nega- dietary feed additive (e.g Akhter et al., 2015; Carbone and Faggio, tively affected by stressful conditions and diseases, which cause serious 2016; Nawaz et al., 2018; Ringø et al., 2014; Song et al., 2014). economic losses (Dhar et al., 2014). Previously, were antibiotics and Prebiotics are indigestible substances that allow specific changes in chemotherapeutics used as treatment strategies towards traditional the composition and/or activity of gastrointestinal microbiota, which diseases. However, these treatments have showed several obstacles and has a positive effect on the nutrition and health status of the host (Ringø restrictions, which include regulatory constraints, inconvenient et al., 2014). Prebiotics play a paramount role in host health when by- ⁎ Corresponding author. E-mail address: [email protected] (E. Ringø). https://doi.org/10.1016/j.aquaculture.2018.06.068 Received 5 May 2018; Received in revised form 23 June 2018; Accepted 23 June 2018 Available online 25 June 2018 0044-8486/ © 2018 Elsevier B.V. All rights reserved. H. Van Doan et al. Aquaculture 495 (2018) 786–793 products in the intestine are fermented by the favorable gut microbiota Table 1 (Choque Delgado et al., 2011; Hoseinifar et al., 2015; Song et al., 2014). The formulation and proximate composition of experimental diet (g kg-1). fi − In this sense, agricultural by-products, rich sources of dietary bre, Ingredients Diets (g kg 1) have been considered as functional food ingredients which can prevent diseases related to modulation of gut the microbiota (Buruiana et al., Diet 1 Diet 2 Diet 3 Diet 4 2017; Li and Komarek, 2017). Since by-products are not often used or Fish meal 270 270 270 270 they are burned, their use as industrial purpose may overcome the Corn meal 200 200 200 200 proper disposal of the wastes, provide value-added income to the Soybean meal 270 270 270 270 farmers, and generate employment (Chapla et al., 2012). Wheat flour 60 60 60 60 Maize is the staple crop with the largest production worldwide, with Rice bran 150 150 150 150 Cellulose 30 25 20 10 an estimate of 1.026 million tons (López-Castillo et al., 2018). Corn- CDXOSa 051020 cobs, which account for 27% to 30% of maize agro-wastes, are potential Soybean oil 2222 feedstuffs for animal feed and feed substrate (Kanengoni et al., 2015; Premixb 10 10 10 10 Melekwe et al., 2016; Wachirapakorn et al., 2016). They have been Vitamin Cc 8888 − used as substrate for growth of numerous bacteria and fungi, for Proximate composition of the experimental diets (g kg 1 dry matter basis) pharmaceutical production, as well as nutraceutically important en- Crude protein 319.36 319.36 319.35 319.33 zymes (Chapla et al., 2012). Xylooligosaccharides, xylitol, and xylose Crude lipid 71.75 71.75 71.75 71.75 Fibre 52.48 52.48 52.48 52.48 are the main components in the corncob waste (Aachary and Prapulla, Ash 106.68 106.97 107.27 107.88 2009; Sun et al., 2015). They are sugar oligomers made up of xylose Dry matter 817.80 817.40 816.90 816.10 units, and according to Chapla et al. (2013) and (Samanta et al., 2015a) GE (cal/g)d 4066 4065 4064 4061 they are considered as important prebiotics. Additionally, xylooligo- a saccharides (XOS) possess wide ranges of biological - and physiological CDXOS = Corn cob derived xylooligosaccharides. b −1 −1 activities, which include; antioxidant activity, blood and skin related Vitamin and trace mineral mix supplemented as follows (IU kg or g kg effects, antimicrobial, antiallergy, antiinfection, antiinflammatory diet): retinyl acetate 1,085,000 IU; cholecalciferol 217,000 IU; D, L-a-toco- properties, selective cytotoxic activity, and immunomodulatory activity pherol acetate 0.5 g; thiamin nitrate 0.5 g; pyridoxine hydrochloride 0.5 g; −1 (Akpinar et al., 2009; Moure et al., 2006; Parajó et al., 2004; Vazquez niacin 3 g; folic 0.05 g; cyanocobalamin 10 g; Ca pantothenate 1 g kg ; inositol 0.5 g; zinc 1 g; copper 0.25 g; manganese 1.32 g; iodine 0.05 g; sodium 7.85 g. et al., 2000). However, to our knowledge, no information is available c Vitamin C 98% 8 g. about the effects of CDXOS on Nile tilapia (Oreochromis niloticus). d GE = Gross energy. Therefore, the present study addressed to evaluate possible effects of CDXOS on skin mucus - and serum immune responses, Streptococcus use. agalactiae resistance, as well as growth performance of Nile tilapia fingerlings. 2.2. Diets preparation 2. Materials and methods The basal diet was formulated according to the known requirements 2.1. Xylooligosaccharide preparation of Nile tilapia (Tiengtam et al., 2015). Four diets were prepared by − incorporating CDXOS: 0 (Diet 1 - control), 5 g kg 1 CDXOS (Diet 2), 2.1.1. Preparation of raw materials − − 10 g kg 1 CDXOS (Diet 3), and 20 g kg 1 CDXOS for Diet 4 (Table 1). Corncob obtained from an experimental farm, Faculty of The selection of CDXOS levels was based on the study of Abdelmalek Agriculture, Chiang Mai University, Thailand. Upon arrival, was et al. (2015). For pellets preparation, fine ingredients were completely corncob dried in oven at 60 °C for 48 h, then ground by using hammer mixed together, and soybean-oil and water were added to produce stiff mill, and filtered with the use of 100-mesh size sieve, and stored at 4 °C dough. The dough was thereafter passed through pellet maker machine until further use. to form pellets, and the wet pellets were collected dried in an oven at 50 °C to obtain moisture content around 10% and stored in plastic bags 2.1.2. Isolation of xylan at 4 °C until further use. Isolation of xylan was carried out as described by Chapla et al. (2012) with some modifications. Briefly, 5 g of corncob powder were thoroughly mixed with 80 mL of 1.25 M NaOH. This mixture was in- 2.3. Fish preparation and experimental design cubated at 37 °C for 24 h in automated shaker (Orbital Shaker In- cubator) at a speed of 150 rpm. Then, it was centrifuged at 10.000 g for Tilapia fry were brought from Chiang Mai Patana Farm, Chiang Mai, 5 min, and the supernatant was gathered and acidified to pH 5.0 with Thailand stocked in a cage (5x5x2 m), and fed commercial diet (CP 37% HCl.