Dr Loc Huu Tran, Founder-Director, Minh Phu Aquamekong ShrimpVet Laboratory, Assistant Professor, Faculty of Fisheries, Nong Lam University, Vietnam
Vietnam has been moving a long way from a very natural based farming system with less biosecurity and antibiotics-based farming protocols to more controlled farming methods since the outbreak of early mortality syndrome (EMS) or Acute Hepatopancreatic Necrosis Disease (AHPND) in 2010 and Enterocytozoon hepatopenaei (EHP) in 2014. Several new practices have been applied including: screening for diseases (EMS/AHPND, EHP, white spot syndrome virus-WSSV) throughout the farming cycle, better pond preparation with good probiotics before stocking, plastic-lined pond farming protocol, nursery phase at the farm level, routine/daily application of bioremediation, daily shrimp pond waste removal, probiotics top-coating in feed, and use of functional feeds.
The presentation will discuss some recent developments in Vietnam’s shrimp farming industry (such as differences in farming models between north and south Vietnam taking into account the environment) and to achieve better productivity, how farmers are using science and innovations at the hatchery, nursery and grow-out phases. With better adaptation to new farming protocols, it appears that shrimp farming in Vietnam has become more predictable, which explains the fast growth in shrimp production in recent years.
As the pathogens for early mortality syndrome (EMS) or Acute Hepatopancreatic Necrosis Disease (AHPND) were characterized and determined in 2013, farms are aware on measures to reduce the impact of AHPND in productions. These include better hatchery, nursery, and grow-out protocols. With regards to hatchery protocols, several improved practices have been applied including: PCR screening for all material (broodstock, live feed, nauplii, and post larvae before harvest), better sanitation, better bio-remediation with focus on Vibrio reduction. The same sanitation, probiotics, and bio-remediation approaches have been applied in nursery and grow-out practices. At ShrimpVet’s facilities, several trials using functional feeds with feed additives added in feed ingredients before extrusion showed positive result in both disease prevention and growth performance. An overall antibiotic-free farming protocol is achievable.
Affecting productivity is also white feces disease (WFD) and working on transmission models, we focus on bacterial etiology. Based on initial result of these studies, several management strategies have been applied, including: algal bloom control, better feed management, probiotics application, better bio-remediation strategies, and functional diets. Those studies have proven to reduce WFD both in laboratory and grow out in pond conditions.
*Co-authors: Vy Van Nguyen, Phuc Hoang, and Trang Nguye, Department of Aquaculture Pathology, College of Fisheries, Nong Lam University