Echinorhynchus gomesi Machado Filho, 1948 infecting the Patinga hybrid (♀ Piaractus mesopotamicus × ♂ Piaractus brachypomus ) in fish farms in Mato Grosso do Sul, Brazil

Abstract

The fish farms state of Mato Grosso do Sul (Brazil) have been facing commercialization problems of the Patinga (Piaractus mesopotamicus (Holmberg, 1887) × Piaractus brachypomus (Cuvier, 1818)) due to hight acanthocephalans infection. The aim of this study was to identify the acanthocephalan species that infect this hybrid and assess the influence of management practices on the intensity of the parasite in fish farms. Samples were collected between October 2017 and June 2018. The transparency was the only water quality parameter that differed among the fish farms, and the values were below the limit established for fish production. Echinorhynchus gomesi was recorded in fish farms A, B and C. There was no significant correlation between the intensity of E. gomesi infections and the length of the intestine, and the standard length of the fish. The intensity of E. gomesi also did not affect the condition of the fish. The results of the study demonstrated that inappropriate management, such as cascading tanks, partial emptying of tanks and successive cultivations without time intervals, created conditions for the establishment of the population of E. gomesi in the evaluated fish farms.