ASIA - Shrimp diseases such as white spot and AHPND have caused devastating losses for farmers across Asia in the last few years. Speaking at Aquaculture Europe 2016, 20-23 September, in Edinburgh Scotland, Dr Andy Shinn, Fish Vet Group, attempts to work out the true economic losses to farmers.
Asia’s crustacean aquaculture is expected to exceed 5.08 million tons in 2016, an increase of 5.46 per cent. However, although there has been an increase in production, the level of growth has been erratic and disrupted by disease outbreaks that have caused huge national economic losses.
Over the last three years, many countries have reported acute hepatopancreatic necrosis disease (AHPND), Enterocytozoon hepatopenaei (EHP) and white spot on their shrimp farms.
Looking at Thailand, the country has clear drops in the production of whiteleg shrimp due to outbreaks of AHPND. Shrimp production dropped from 10.6 tons per hectare in 2010 to 4.13 tons in 2013.
As well as the economic losses, it is thought that the disease has also led to the loss of 100,000 jobs.
Through looking at current production and future estimates, Dr Shinn estimates that the economic losses for Thailand due to AHPND from 2011 to now is roughly US$7.38 billion.
In VietNam’s Mekong Delta, AHPND in 2015 caused losses of US$8.9 million in whiteleg shrimp and US$1.8 million in tiger shrimp.
As well as this, white spot caused losses in whiteleg shrimp production of US$5.6 million and $2.3 million in tiger shrimp.
EHP, a microsporidian parasite, was first described in shrimp in 2009. Confined to the heptopancreas, this disease does not tend to cause excessive mortality but it does stunt growth.
The value of shrimp therefore drops as farmers have to sell them at a much smaller size.
In Thailand, losses from EHP are predicted to be around US$76.4 million, although Dr Shinn notes that there is currently little data available. This figure may therefore change as more data becomes available.
In order to prevent disease on your farm, Dr Shinn recommends farmers to practice strict biosecurity.
“Make sure you check broodstock health and only buy quality seed and feed,” advised Dr Shinn.
It is also important to check your water quality regularly and keep the pond bottom clean, he concluded.