Contents lists available at ScienceDirect Aquaculture journal homepage: www.elsevier.com/locate/aquaculture Tailoring shrimp aquafeed to tackle Acute Hepatopancreatic Necrosis Disease by inclusion of industry-friendly seaweed extracts Rafael Félix a,1 , Carina Félix a,1 , Adriana P. Januário a , Ana M. Carmona a , Teresa Baptista a , Rui A. Gonçalves b,2 , João Sendão c,3 , Sara C. Novais a , Marco F.L. Lemos a, ⁎ a MARE – Marine and Environmental Sciences Centre, ESTM, Instituto Politécnico de Leiria, Portugal b BIOMIN Holding GmbH, Erber Campus 1 3131, Getzersdorf, Austria c Biomin Vietnam Co., Ltd, Chăn Nuôi, Dương Xá, Gia Lâm, Hà Nội, Viet Nam ARTICLE INFO Keywords: AHPND Bioactive compounds Invasive seaweeds Shrimp feed Vibriosis ABSTRACT Shrimp farming has been severely affected by Vibrio infections in southeastern Asia, with severe economic impacts. Invasive seaweeds are an increasing threat that can be strategically valorized by biotechnology, pro- moting economic development while contributing to ecologic remediation. Asparagopsis armata and Sargassum muticum are two such species that have been frequently reported as excellent bioactive compounds producers, namely anti-bacterial and antioxidant. Thus, A. armata and S. muticum were extracted in an industry-focused approach, using low amounts of ethanol and short extraction times at room temperature. Yield, in vitro anti- oxidant capacity by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay, and in vitro antibacterial ac- tivity against Vibrio parahaemolyticus (microdilution) were optimized using Response Surface Methodology (RSM). Optimal extracts (one from each seaweed species) were incorporated in feed, and an in vivo trial using the whiteleg shrimp Penaeus vannamei was performed in industrial facilities using the supplemented feed (1.5, 3.5 and 7.5 g extract per kg feed). Feed quality (along an 8-week period under regular storage conditions) and shrimp performance (40-day trial) were studied, as well as post-challenge (infection by virulent Vibrio para- haemolyticus) mortality rate and hepatopancreas condition. The results from the RSM showed that lower ex- traction times and ethanol volumes maximized extracts' bioactive properties (A. armata – 20 min, 10 mL solvent per gram seaweed; S. muticum – 100 min, 10 mL.g -1 ). The seaweed extracts did not impact shrimp performance (no statistically significant differences in weight gain, feed conversion rate or survival). Asparagopsis armata selected extract at 7.5 g per kg feed was able to decrease feed contamination by fungi along time and reduce shrimp mortality by up to 50% upon challenge with V. parahaemolyticus. Despite lacking statistical significance, a difference in hepatopancreas condition after challenge could be identified in shrimp fed the supplemented feed. 1. Introduction In a world with a rapidly increasing population and relatively static capture fishery production, aquaculture has emerged as a solution for supplying seafood for human consumption. It provides an affordable source of high-quality animal protein, lipids and other nutrients (Vignesh et al., 2011), and global consumption is expected to increase continuously (Ranjan et al., 2017; Marc Antonyak et al., 2018). In Asia, shrimp farming has increased in the last 30–40 years, especially in Southeast Asia (Holmström et al., 2003), but the global rise of intensive aquaculture is a risk factor for disease outbreaks and consequent mor- tality of cultured stock (Vignesh et al., 2011; Ranjan et al., 2017). Among the most common diseases affecting shrimp farming in Asia is vibriosis, a bacterial infection caused by species of Vibrio (Toranzo et al., 2005). In Asia, pathogenic isolates of Vibrio parahaemolyticus is responsible for causing acute hepatopancreatic necrosis disease (AHPND), informally known as early mortality syndrome (EMS) by the farming community (Thitamadee et al., 2016), causing high mortality rates in shrimp cultures and consequent high economic losses (Shinn et al., 2018b). Along with the pathogen's proliferation, it has been https://doi.org/10.1016/j.aquaculture.2020.735661 Received 5 March 2020; Received in revised form 26 June 2020; Accepted 26 June 2020 ⁎ Corresponding author. E-mail address: marco.lemos@ipleiria.pt (M.F.L. Lemos). 1 Both authors contributed equally to this work. 2 Currently at Lucta S.A. Innovation Division – Feed Additives, UAB Research Park, Edifici Eureka, 08193 Bellaterra, Barcelona, Spain. 3 Currently at Skretting South Asia, Viet Nam. Aquaculture 529 (2020) 735661 Available online 05 July 2020 0044-8486/ © 2020 Elsevier B.V. All rights reserved. T