Blood characteristics of Pirapitinga do sul, Brycon sp, under experimental conditions of intensive rearing

Abstract

This work, performed during March 84 to May86, was done uith specimens of "pirapitinga do sul", Brycon sp., from Estação de Aquicultura de Paraibuna owned by the Companhia Energética de São Paulo (CESP).Two groups of 400 fishes were put in tanks measuring10x20 m, respectively with 1.4 and 2.6 years old. Monthly, 10 specimens from each tank were captured and transported to the Instituto de Pesca-SP, when total length and weight were taken under anesthetics. The blood was withdrawn using a disposable syringes and needles, and utilized for total erythrocyte counts, (Er = 10⁴/mm³), hematocrit (Ht = %) and hemoglobin concentration (Hb = mg%). With these data the hematimetric absolute indexes were calculated: VCM = µm³, HCM = µµg e CHCM = %. Differences were found neither between male and female means nor between the gonadal maturation stages, but a discret increase of these means was observed with the advancement of the gonadal maturation. The mean values of the hematologic analyses were superior for the C ₁₄ tank when compared with those of the C ₁₃ tank. It was also found a significant correlation between the hematologic variables Er, Ht and Hb.