GOAL: Shrimp diseases continue to vex farmers in Vietnam
White spot virus, early mortality syndrome (EMS), Enterocytozoon hepatopenaei (EHS), and white feces disease continue to be of concern for Vietnamese shrimp farmers and their economic peace of mind.
According to Maple Hung, the vice president of global market for Sheng Long Bio-tech International Co., the current state of Vietnam’s shrimp aquaculture sector still sees white spot virus, EMS, and white feces disease causing economic loss. However, “the business is growing,” Hung said on 6 October at the Global Aquaculture Alliance’s GOAL 2017 conference in Dublin, Ireland.
Loc Tran, director of shrimp for Vet Laboratory in Vietnam, also listed diseases – alongside unpredictable weather as well as farmers’ lack of finances and technology – as persistent obstacles for the sector.
While exhibiting no overall major changes from years past, increased heavy rains and flooding have seemingly made white spot virus’ presence in the Mekong Delta more widespread, Tran said. Meanwhile, the instances of EHP are on the rise, added Tran, with many cases being detected in hatcheries and shrimp ponds in Vietnam, slowing growth.
Appearances of the newer white feces disease, which was first recorded in 2010 in Thailand, has also been on the upswing, said Hung. The ailment, which wrecks havoc on the digestive systems of shrimp, “is strongly associated with pollution and excess algae, which lead to blooms of bacteria on pond bottoms,” noted Tran.
Disease challenges aside, farmed shrimp growout technology has been advancing for Vietnam, improving pond results with “semi-biofloc and zero water exchange with probiotic culture,” explained Hung. Vannamei is also growing fast in the country, and several farms seem to be shifting to monodon in response to higher prices, Hung said.
Shrimp farming is currently expanding in Vietnam, added Tran, with "low salinity" farming protocols being adopted in particular areas.