May 10, 2016

 

Licking or living with EMS

 

By Rick Alberto

Seven years ago, EMS, which is short for early mortality syndrome, a shrimp disease, first appeared in China, spreading to other Asian countries, which produces 75% of the world's farmed shrimp.

 

The disease, also known as AHPNS (acute hepatopancreatic necrosis syndrome) or AHPND (acute hepatopancreatic necrosis disease), has been controlled but so far has not been totally eliminated in the major shrimp-producing countries such as Thailand, Vietnam and Malaysia.

 

The savageness of the disease, whose mortality rate is as high as 70%, can be gleaned from how it almost emaciated the shrimp farms in Thailand, which used to be the world's second-largest shrimp producer. EMS first hit Thailand's eastern provinces of Rayong, Chantaburi, Trad and Chachoengsao in 2012 and later surfaced in the country's southern aquaculture belt. During a survey conducted in February-May 2013 by the Thai Department of Fisheries, at least 25 provinces have been hit by EMS.

 

As early as 2013 farmed shrimp production in Thailand dropped by nearly 60% to 250,000 tonnes from what it used to produce—600,000 tonnes. Exports plummeted as many processing plants were forced to shut down due to shortage of raw material. Shrimp processor and exporter CP Foods laid off 1,200 workers and set up a processing facility in Vietnam, a move seen as a shift by the industry away from exports of raw frozen shrimp to value-added exports. 

According to the Global Aquaculture Alliance, the EMS was causing annual losses of more than US$1 billion.

 

Can EMS be wiped out?

 

The question is, can the disease be wiped out? The answer, it seems, is no, at least for now. Otherwise, "you'll have to set up a farm in the moon, and there's not enough water there", Peter Coutteau, Nutriad business unit manager, said in jest during an interview with eFeedLink at the sidelines of the Asia-Pacific Aquaculture 2016 in Surabaya, Indonesia, on April 28.

 

"EMS is something we will have to live with like many other diseases. It is very difficult to eradicate from the environment", Coutteau said, adding that it can be managed or controlled and probably avoid it.

 

According to Coutteau, disease management is a combination of managing the farm and its microbial ecology (such as improvement of hatchery sanitation, broodstock management and quality of postlarvae). "We also believe", he added, "that the feed additives, which can manipulate the microflora (microorganisms) through the feed, have a role to play".  Probiotics can also manipulate the environment, in this case the water column in the pond.

 

The Nutriad executive described the Asian shrimp industry as "a bit on standby" mode. "Nobody really knows how the situation is going to be" although "there's a bit of optimism in Thailand that for the first time since the outbreak of EMS they're going to go back up in production".

 

While the shrimp industry is now "out of the bottom", Coutteau warned that the recovery is going to be a slow process.