Asia's shrimp industry facing long road to recovery : May 3, 2013
John Fiorillo , Rachel Mutter , Elisabeth Fischer : IntraFish
The shrimp industry welcomes the news EMS is caused by a bacteria, but how quick will the turnaround to pre-disease production levels be?
The news that the cause of the early mortality syndrome (EMS) has been identified should be a welcome change to the struggling Asian vannamei industry.
A team of researchers at the University of Arizona found the disease is caused by a bacterial agent, which is transmitted orally, colonizes the shrimp gastrointestinal tract and produces a toxin that causes tissue destruction and dysfunction of the shrimp digestive organ known as the hepatopancreas.
It is good news for producers, suppliers — and buyers. However, chances are a rehabilitation of production back to pre-EMS levels could take a while.
“If it is [caused by] bacteria, normally the prevention is antibiotics,” Arianto Yohan, head of production and sales at Indonesian producer CP Prima — who has so far been unscathed by EMS — told IntraFish. “But as we know, antibiotics are not allowed.”
It will be interesting to see what the recommended farming procedures will be to prevent it, he said.
Jim Gulkin, managing director at Siam Canadian, welcomed the news, but pointed out everything depends on “how quick the turnaround is going to be.”
He expects the sector to be “out of the woods” within the next year.
“I’m thrilled they found the source of EMS,” also said Ernie Wayland, executive vice president of US importer International Marketing Specialists (IMS), “but how long will it take to develop and antibiotics and put it through the rigorous testing required?”
Wayland told IntraFish any positive results stemming from the discovery of the bacteria responsible for EMS will likely take a while. “It’s probably going to take longer than folks realize.”
Improvements need to start at brood stock level
George Chamberlain, president of the Global Aquaculture Alliance (GAA) and the Responsible Aquaculture Foundation, said confirmation of the EMS pathogen as a bacterium “provides immediate clues toward improved hatchery and pond management.”
“For example, techniques such as proper sanitation, disinfection, and competitive exclusion through use of probiotics are expected to be helpful,” he told IntraFish in an email.
Isolation of the EMS pathogen also provides a means to conduct laboratory challenge trials to determine which genetic lines, which probiotics, which immunostimulants, and so on, are most effective, he said.
In addition, the “imminent development of sensitive molecular diagnostic tests will enable breeding programs and hatcheries to assure their brood stock and post larvae are clean.”
Pond management will be difficult in environments where EMS is already established, Chamberlain said, but sensitive diagnostic tests will reveal which protocols are more effective.
“It is unlikely that EMS will be eliminated from the environment in the near term, but continual development of improved management tools will progressively increase yields to pre-EMS levels,” he told IntraFish.
Gulkin concurs with Chamberlain, saying the first steps of improvement need to be taken at a brood stock level.
“The next step is really at the brood stock level, the producers in Hawaii and Florida and anywhere else in the world where they are producing brood stock — I think that’s where it starts,” he said.
Lack in research funding
However, the speed of technology development depends on research budgets.
“Sadly, research funding lagged nearly three years behind the initial detection of EMS,” Chamberlain said. “With proper funding, diagnostic tools and challenge trials can be developed and widely implemented in six to 12 months.”
This will quickly lead to improved health status of post larvae, he said.
“Access to sensitive diagnostic tests will lead to improved pond management techniques within one to two years. Breeding for EMS resistance is a longer term process which is likely to require three to five years.”
Keep stocking densities low
Yohan was keen to emphasize that even if a “cure” is found for EMS, there are many other shrimp diseases — and if anything, EMS has continued to remind CP Prima not to push its stocking densities too high.
“I do hope other producers will restrain themselves even if a cure is found,” he said.
On recovery of volumes, Yohan said “from our experience, volumes will only start to pick up again when farmers have confidence in the farming system.”
Considering this confidence probably only comes from reduced stocking densities, supplies will not get back to previous volumes in the short term, he said.
However, Gulkin said, farmers in Thailand have already gained confidence, and are re-seeding their farms.
“Here in Thailand it looks like some improvement already,” he told IntraFish. “We’re seeing the ponds in eastern Thailand, which represent 30 to 35 percent of the output of the country, mostly re-seeded already and we’re waiting to see what type of production is going to come out there.
“The south of Thailand has been much slower, the farmers have been much more cautious and conservative,” he said.