Breeding tilapia with shrimp helps prevent the shellfish from catching the white spot virus. (Photo: Stock File/FIS)
Tilapia helps prevent deadly virus against shrimp
Thursday, March 31, 2011, 16:20 (GMT + 9)
Researchers at the Federal University of Santa Catarina (UFSC) have found that raising white shrimp (Litopenaeus vannamei) and tilapia (Oreochromis niloticus) in the same pond promotes an ecological balance and a healthy development of both species, as well as preventing the death of crustaceans by the white spot virus.
This initiative, by the aquaculture engineer Frederico Santos da Costa, consists of a polyculture system which originally had another purpose: that small farmers in Santa Catarina have an alternative income from tilapia farming if their shrimp production was lost due to white spot, reports Ciência Hoje.
This disease severely affected shrimp from the coast of Santa Catarina in 2004 and led to losses of BRL 6 million (USD 3.6 million) for producers.
"The coexistence of animals creates a balance that prevents the death of shrimp from white spot," said Santos da Costa.
The experiments began in 2007 through a partnership between UFSC and the municipality of Barra do Sul.
While the white spot virus is not harmful to human health, it harm the marketing of shrimp because the virus carriers die before being harvested.
"In two days, the shrimp is already in a state of decomposition, making it unfeasible for consumption," said the expert.
During tests, Santos da Costa found that shrimp would go down to the bottom of the tank while tilapia remained on the surface of the water, where they feed on various types of microorganisms that are harmful to the shellfish.
That is, the tilapia act as 'environmental disinfectants', preventing the shrimp from becoming infected.
Santos da Costa is now conducting tests to introduce a third species in to the same pond, the native oyster (Crassostrea brasiliana), a mollusk that acts as a filter in the marine ecosystem and also has good commercial value.
By Analia Murias