Aquaculture news

Cawthron scientists are working with industry to breed virus resilient oysters
15 August 2013

Latest research delivers encouraging signs for oyster industry

A collaborative research programme to breed oysters resilient to a virus that three years ago devastated New Zealand's Pacific oyster industry is starting to deliver promising results.

Scientists at Cawthron Institute, together with industry partners, have been working towards breeding Pacific oysters resilient to the ostreid herpes (OsHV-1) virus that almost wiped out the country's Pacific oyster stocks in 2010.

"We have identified oyster families with a very high survival rate when exposed to the oyster virus, which decimated stocks in 2010," Cawthron Institute Chief Executive Charles Eason says. "These recent findings are most encouraging. They suggest that selective breeding has great potential to address the current crisis."

While the latest results are encouraging, there is still a lot more work to be done, he says.

"There are still further trials to go. These are very encouraging preliminary results for our long-term breeding programme, highlighting that through a combination of improved genetics and husbandry, promising outcomes may be achieved in a very short time frame."

Cawthron scientists have been researching the resilience of Pacific oysters to the virus since 2010 when it first hit New Zealand. The virus caused 90 percent losses in the wild caught spat the industry heavily relied on for its marine farm stocks. The crisis led to job losses, factory closures and saw an overall drop in production of 50 to 60 percent, with some individual farmers hit significantly harder.

When the virus hit, Cawthron Institute was already involved in a joint research project with industry partners into breeding of oyster spat.

"When the virus hit we all worked together to address this problem," says Cawthron Institute Cultured Shellfish Programme Leader Nick King. "We could not have got this far without the huge support we have received from our industry partners, in particular Pacific Marine Farms - a subsidiary of Aotearoa Fisheries Limited, and Te Matuku Bay Oysters, who managed the bulk of the on-farm trials. It is truly a joint effort."

The research and farm trials indicate that a combination of genetic improvement through breeding, and improved farm husbandry - such as by growing oysters to a larger size and age before exposure to the virus, makes a big difference in terms of oyster survivorship and a return to viable production.

"We're hoping these new breeding strategies will help us achieve genetic gains in a relatively short time frame," Cawthron Aquaculture Manager Dr Jacquie Reed says.

"We are fully aware that timing is critical in times of crisis, and the industry needs fast results to survive."

To find out more about this research please contact Nick King.