Desempenho zootécnico de tambaquis (Colossoma macropomum, Cuvier 1818) da primeira geração de seleção genética para ganho de peso

Abstract

Aimed to monitor the production performance, morphometric characteristics and analyze the growth pattern of tambaquis the first generation of genetic selection for weight gain. The study was conducted from September 2012 to May 2013, in Santo Antônio de Leverger - Mato Grosso, Brazil. Seven families from the breeding program and a control group (no improvement) were studied. All animals were individually microchipped. Were evaluated and measured the following characteristics: weight gain, total length, standard length, head size, height, width and perimeter of the body. The experiment followed a completely randomized design and data collected for nine monthly biometrics groups of genetically improved tambaqui and control (no improvement) were evaluated. To describe the production performance of tambaquis, comparisons between treatments (families and control) we used the Dunnett test with 5% significance and the growth behavior of tambaquis used the nonlinear mathematical model of Gompertz regression. Five out of seven families (A, B, D, E and G) had higher final weight, average daily gain and morphometric growth compared to the control (no improvement). Only the C family breeding program presented final weight, average daily gain and lower morphometric characteristics compared to the control (no improvement) and F family presented similar to the control (no improvement) results. Genetically improved animals showed different pattern of growth and higher compared to unimproved animals (control group), in the case, especially the asymptotic weight.