Uso do boroscópio na identificação sexual do pirarucu / Use of boroscope in sexual identification of pirarucu

ABSTRACT

Pirarucu, Arapaima gigas, known as "Brazilian codfish", has promising zootechnical characteristics and great acceptance in the market. However, the shortage of knowledge about reproductive biology, the absence of external sexual dimorphism and a safe method for doing, become obstacles to the multiply of the species. What has encouraged the development of methods applied for this purpose at low cost and easy acquisition, such as boroscopy. In this work, the objective was to use the borescope to view the gonads and sexual identification of Arapaima gigas, in cultivation farms in the state of Maranhão. In the present study, 15 specimens from pirarucu breeding farms located in the cities of Alto Alegre do Pindaré and Santa Inês were used. These specimens had their abdomen inflated with saline solution 5% and the images obtained from the male specimens showed the peculiar gonad on the left side, smooth, elongated and with a relatively clear orange color, supported by muscle tissue, and in the females the oocytes were visualized in layers, or scaly-like tissue, in immature females, and with a rounded shape with a slightly whitish color in the celomic cavity. Boroscopy show to be useful for the sexual determination of specimens of pirarucu, with low cost, speed and formation of clear images.