Innovative microbial-based solutions for sustainable shrimp farming
At the Lallemand booth, from left, Khurshid Anwar (Bangladesh), Dhanunjaya Goud (India), Stephane Ralite (France) and visitors, Thomas Levallois and Teddy Njoto, Maqpro, Indonesia.
Lallemand Animal Nutrition, shared the results of new studies conducted in partnership with ShrimpVet Laboratory at Nong Lam University. These studies encompass the development and evaluation of functional feed ingredients to help address important shrimp health issues such as Enterocytozoon hepatopenaei (EHP) challenge, or white faeces syndrome (WFS), as well as the development of integrated bioremediation strategies for pond water management. They suggest different approaches to answer important issues of shrimp health, nutrition and management in a sustainable way.
New perspectives on microbialbased functional ingredients EHP is an intracellular parasite that targets the shrimp hepatopancreas and gut epithelial lining, causing stunted growth. It generates severe losses across Asia, either directly or in association with other pathogens. The trial results were presented by Eric Leclercq, Ph.D., Aquaculture R&D and Technical Support Manager with Lallemand Animal Nutrition. The trial was conducted at ShrimpVet Laboratory in Ho Chi Minh City, Vietnam, on EHP-challenged juvenile whiteleg shrimp. It evaluated a multistrain yeast-based additive (YANG) developed by Lallemand Animal Nutrition with enhanced immune-modulating properties and binding activities against undesirable bacteria. The additive was fed for 14-days prior to the disease challenge and during the challenge period. “With YANG, the pathogen load in the hepatopancreas, measured by qPCR, was reduced at all time points and by up to 64% at the peak of infection. As a result, the body weight of challenged shrimp was 7.9 % higher, thanks to, interestingly, a much reduced prevalence of severely compromised animals,” Leclercq explained. “YANG, applied preventively and over an EHP challenge period, can thus help contribute to reducing the severity of the EHP outbreak and related loss of growth. Importantly, ‘runt’ shrimp typically act as disease reservoir, so reducing their prevalence can help safeguard the crop to harvest.” As with EHP, WFS is a pathology that not only strongly affects shrimp growth and FCR, but also survival. The infectious nature of the syndrome, and development of a challenge model, were only recently described by Dr Loc Tran from ShrimpVet Laboratory. The trial presented at the conference assessed the potential of YANG to help mitigate the severity and impact of the syndrome, using the recently available WFS challenge model. Results indicated a lower prevalence of gross symptoms at the peak of
infection, a lower loss of body-weight and a clear trend towards a higher survival. This highlights for the first time, YANG's unique properties, the potential of a microbial-based solution as part of an integrated management program to support good health and performance under these conditions.
Bioremediation approach Bioremediation is defined as: “The treatment of pollutants or waste by the use of microorganisms (such as bacteria) that breakdown undesirable substances.” The concept has been applied to aquaculture for decades with the goal of managing organic matter accumulation and nitrogen compounds in ponds. Bioremediation can be powerful but is also a complex technology requiring informed management attuned to local conditions and targets. Based on in vitro, pilot-scale and field trials, Leclercq discussed some key success factors in the selection and deployment of an effective bioremediation strategy for shrimp farming. Distinct microbial solutions are available, each addressing specific aspects of the pond system. When properly applied and combined, bioremediation solutions can become powerful tools to secure and increase the capacity of the pond to carry a healthy crop to harvest. (www.lallemandanimalnutrition.com).
Presentations at Asian-Pacific Aquaculture 2018 conference, April 22-26 2018, Taipei, Taiwan. Eric Leclercq, Stéphane Ralite, Phuc Hoang, Loc Tran, and Mathieu Castex. Effect of a multi-strain yeast-based functional additive on EHP-challenged juvenile white shrimp. Eric Leclercq, Stéphane Ralite, Diên Nguyễn, Loc Tran, and Mathieu Castex. Effect of selected functional health feed on white shrimp Litopenaeus vannamei challenged with a novel infection model for white faeces syndrome. Eric Leclercq, Stéphane Ralite, and Mathieu Castex. Some critical steps to the successful development and deployment of an integrated bioremediation strategy in pond aquaculture.
July/August 2018 AQUA Culture Asia Pacific Magazine
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