Gamitana or tambaqui, Colossoma macropomum. (Photo: Tino Strauss)
Amazonian farmed fish mortality intended to be reduced
Friday, November 30, 2012, 04:00 (GMT + 9)
Scientists of the National Research Institute of Amazonia (INPA) are studying how to help reduce the mortality rate of farmed fish of Amazonian waters.
Research is expected to identify disease-causing bacteria in specimens of paiche (arapiama), gamitana (tambaqui) and matrinxã.
Furthermore, the study is expected to serve as a basis to define preventive measures to reduce the mortality of these species bred in captivity.
The study is funded by the Foundation for Research Support of the State of Amazonas (Fapeam) and was developed in the last two years by the scientist Eliane Cardoso Carvalho under the project 'Phenotypic and molecular identification of pathogenic bacteria associated with Amazonian fish farming,' Globo.com reported.
The researcher explained that knowing the variety of bacterial species that cause disease in Amazonian fish of commercial interest is extremely important to ensure the reduction of economic losses for producers.
"Infections in fish are responsible for heavy losses in factory farms, which, many times, have a mortality rate that can approach 100 per cent," Cardoso Carvalho stated.
She stressed that the bacteria of the genera Aeromonas, Cytophaga, Mycobacterium and Pseudomonas are present in ponds, and also said that there are other factors that cause stress to the fish and can cause disease outbreaks.
To identify other bacteria, the group analysed 72 bacterial fish isolates.
"They were 28 paiche isolates, 17 gamitana aisolates and 26 matrinxã isolates, where 35 bacterial species were identified. Out of these, 11 had not been described before and for the others there are prophylactic measures," explained Cardoso Carvalho.
Currently, tambaqui is the species having major commercial importance for the fishing and fish farming activities in the Amazon region, with an annual output of 3,500 tonnes.
Meanwhile, about 6,000 tonnes of matrinxã are annually produced, which supply 74 per cent of the country and pirarucu production is estimated to be at 1,800 tonnes in three fishing regions: Amazônia Peruara, the Brazil-Peru-Colombia border, and Amazônia Central.
By Analia Murias