Pacific Oyster Mortality Syndrome (POMS) is a disease caused by a virus. POMS is harmless to humans but lethal to oysters, causing up to 90 per cent mortality in a crop of millions within days. It weakens the oyster, causing the shells to open and die.

The first POMS outbreak was observed in 2007 in France, which nearly wiped out the oyster industry, and in 2010, New Zealand's Pacific Oysters succumbed to the virus that causes POMS, OsHV-1. Eight months later, POMS entered Botany Bay's Georges River in Australia. Again, huge losses were seen at Pacific Oyster farms.

 

By 2013, POMS had spread to a second New South Wales estuary, the Hawkesbury River, which is known for its large oyster production in NSW. The disease killed more than 10 million oysters over three days. Then, in January 2016, POMS made its way to Southern Tasmanian waters. It had previously been considered an unlikely destination for POMS in Australia as the disease preference for water temperatures above 21-22°C. The Tasmanian industry lost 50 employees and 60% of the state's growing areas were affected by it.

 

The Australian oyster industry's survival lay in the hands of a genetic program set up by the industry's breeding program, Australian Seafood Industries (ASI). Prior to POMS reaching New Zealand, ASI had been working closely with CSIRO and the NSW Department of Primary Industries (DPI) on the genetic improvement of Pacific Oysters through selective breeding. Its research focused on creating larger and more robust Pacific Oysters, but the direction quickly changed once POMS attacked.

 

After the POMS breakout in Georges River, oysters from ASI's 80 distinct family 'lines' were relocated from clean locations to the 'diseased' estuary to test the genetic difference in POMS survival. NSW DPI ran field trials and CSIRO analysed survival data for the different genetic lines. CSIRO found that there was a strong genetic basis for POMS survival.

 

After several years of breeding with the primary goal of POMS resistance, the Tasmanian industry feels comfortable with the level of POMS resistance ASI has currently bred into our family lines. We are now following the industry's direction, focusing heavily on incorporating strong commercial traits into these highly resistant POMS families. Furthermore, it is a focus to breed resilience into our family lines to thrive in harsh conditions like the west coast of the Eyre Peninsula in South Australia.

 

With the help of the FRDC, we have recently finished a project that focuses on South Australian survivability. We found that the genetic trends of oysters that survived in high numbers in South Australia were highly heritable, and we are now incorporating this trait into our program to ensure increased profitability in the Australian oyster industry. ASI breeds up to 120 family lines annually with a multi-trait focus. We aim to mirror industry and be a direct line between commercial farms and research and development.

 

Moving forward, with the FRDC's help, we have just commenced a project to implement genomic selection into our breeding program. We have developed a genotyping chip with our colleagues at the Centre for Aquaculture Technology in San Diego. Genomics will allow our program to drive gains 40% faster than we were under family production. We are also encouraging industry to genotype their broodstock to further drive growth and profitability in our industry.