Revista Estratégica vol.10 - Faap

The tanks were randomly populated with specimens of tambaqui (Colossoma macropomum)
and pirarucu (Arapaima gigas). The tambaqui fingerlings had an average
length of 5 cm and an average weight of 100 grams, while the fingerlings of pirarucu
had an average length of 15 cm and an average weight of 300 grams. During the 12
months of experiment, the animals were fed with commercial extruded type food. The
amount of food provided was adjusted by means of biometry performed in 10% of
the population of each tank. Maintenance, transparency, and adjustment of fertilization
were performed using the Secchi disk to 35 cm.
Every 30 days a Biometry was performed to monitor the development of the fish
and to check the weight gain. The program of biometrics and food supply is shown in
Appendix (Table 5).
In relation to food, practically all organisms in the pond contribute with the feeding
of the fish. The greater or lesser number of these organisms influences the production
of fish increasing or decreasing the productive capacity respectively.
Because it is a semi-intensive system, artificial food was administered periodically
and the food used was extruded or floating types. After a year of settlement and with
the weight of 2.0 kg for tambaqui and two years for pirarucu with 20 kg in average, the
removal of the fish was performed with the usage of trawl net, with 25 mm mesh, wire
multifilament nylon No. 18. The Table 1 sets out the costs of deployment for the recovery
of 5.5 ha of degraded area by clay mining by Santa Maria Ceramics.
In Table 2, it is represented the cost of producing a 12-month cycle for the Tambaqui
species and 24 months for Pirarucu species in an area of 5.5 ha of clay extraction.
Results achieved in production
As Table 3 shows, it can be seen that the final biomass gain for the tambaqui species
was 22,400 kg, and for the pirarucu species it was 24,600 kilograms on average. Regarding
the mortality rate, it was 11% for tambaqui species and 18% for the pirarucu species,
thus resulting in a survival of 89% and 82% for Tambaqui and Pirarucu respectively.
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Estratégica, vol.10(02), dezembro.2010