The new vaccine developed by Merck protects tilapia from one of the dearest diseases affecting its farming. (Photo: Merck/FIS)
Tuesday, August 19, 2014, 03:50 (GMT + 9)
MSD Animal Health (known as Merck Animal Health in the US and Canada) launched a new fish vaccine as a promising measure to help protect tilapia and other fish against the biotype 1 strain of Streptococcus agalactiae.
This disease is the biotype specific to Thailand and other key tilapia-producing regions in Asia, including Malaysia.
“We are pleased to introduce a new fish vaccine to help producers protect their fish from one of the most costly diseases affecting the species,” said Norman Lim, Regional Technical Manager for aquaculture in Asia, MSD Animal Health.
“The vaccine is backed by MSD Animal Health’s ‘Strep Control: Your Tilapia Health’ program, which provides producers with the support they need to implement an effective vaccination and control program,” Lim added.
Animal health specialised firm conducted extensive sampling of farms in the world’s most important tilapia-producing regions and found that Streptococcus accounted for 70 per cent of all pathogens collected, making it the most prevalent disease affecting tilapia. Of the two Streptococcus strains that have been identified, S. agalactiae is the most economically damaging, causing widespread mortality and morbidity in larger fish.
In a laboratory test, fish experienced full onset of immunity one week after vaccination with this vaccine and protection was demonstrated to last for at least 12 weeks. In a large-scale field trial in an environment challenged by S. agalactiaebiotype 1, the fish vaccine increased survival by 17 per cent, increased biomass by 11.2 per cent, and improved feed conversion efficiency by nine per cent. Protection was demonstrated for the entire grow-out period.
The fish vaccine provides specific protection against the biotype 1 strain of S. agalactiae, the main cause of Streptococcosis in tilapia in Thailand. Fish vaccinated with the vaccine are safe for human consumption.
As part of the ‘Strep Control: Your Tilapia Health’ program, MSD Animal Health can help producers confirm the strain and biotype present on their farm, implement a surveillance and vaccination program, and train staff on appropriate control strategies.