Early mortality syndrome (EMS) continues to take its toll on the shrimp farming industry, but advanced knowledge is leading to improved practices and better control of the disease.
That’s according to The Global Aquaculture Alliance (GAA), whose president, George Chamberlain, made a presentation to the National Fisheries Institute in late May, two months after the GAA launched a case study to identify key shrimp-farming practices that can prevent the disease.
Mr Chamberlain shared a number of observations during the presentation made by the expert GMS committee formed by the GAA.
He said that the disease is still difficult to quantify because although test methods are improving, EMS losses continue to be confused with those caused by viral disease such as white spot and Taura syndrome.
The disease is thought to be transmitted vertically on the outside of eggs from broodstock to postlarvae and can also transfer to shrimp via contagens in water.
The trouble is that once the disease is established it’s difficult to control. In China, antibiotics have been found to be ineffective against the disease because the bacteria responsible are resistant.
But the GAA has a number of recommendations to help control the disease including only breeding from EMS free broodstock, improving farming practices – which includes carefully monitoring water and bottom quality, and employing a nursery phase to confirm postlarvae are free from EMS before they are released.
The organisation is launching a new online survey to further tackle the issue. It aims to collect additional information on the EMS status of farms in affected areas along with measures employed to tackle the issue.
