Genetic Mapping Helps Fingerling Producers

Lucy Towers
29 October 2012, at 12:00am

BRAZIL - Embrapa Aquaculture and Fisheries, under the Ministry of Agriculture, Livestock and Supply (MAPA), was at the forefront of technical training in genetics and management of breeding native fish, on 20 October at Fazenda So Paulo fingerlings in Brejinho of Nazareth, Tocantins. Around 40 fingerling producers in the states of Gois, Maranho, Par, Rondnia and Tocantins were present.

According to Embrapa Fisheries and Aquaculture researcher, Anderson Alves, the first step is to control production to identify each animal. When purchasing cattle, for example, the farmer has access to the animals genetic and performance history of their previous generations. This allows control of the quality, something which fish farmers usually do not have control of.

Fish identification must be made by devices that can be permanently fixed in animals. One of the more reliable are tags which are small capsules electronically injected via a syringe into the muscle of the animal.

Each tag has a unique serial number that is read by a scanner which is passed over the skin of the fish. "This system is equivalent to numerical earrings that are placed in cattle," said the Embrapa researcher.

"After identification, we need to draw the animal's genetic profile number." This occurs through DNA analysis performed on tissue removed from the fish.

Knowledge of the genetic profile allows the choice of the best crosses, avoiding cross with fish very close kinship. "The inbreeding increases the chance of obtaining offspring with genetic problems such as disease susceptibility and low productivity," said the expert.

Moreover, the genetic mapping of fish also allows greater quality control, identification of the best players in addition to maintaining and improving the lots sold, which translates into increased productivity and profits.

Mr Alves announced that Embrapa is initiating a programme of genetic variability of fish which will give an overview of the main genetic Brazilian native species. The archive will enable the collection of information as the proportion found among pure and hybrid specimens and genetic similarities and differences found in animal and fish farms in the major river basins in Brazil.