Erythrocyte parameters and condition factor of Gymnotus spp. (Gymnotiformes: Gymnotidae) under culture conditions

Abstract

The aim of this study was to evaluate the erythrocyte variables and body conditions of tuvira, Gymnotus spp., under culture conditions. A total of 42 fish with an average weight of 42.9 ± 31.8 g and average length of 23.7 ± 3.3 cm from a commercial “bait house” were used. After fish anesthesia with clove oil, 1.5 mL of blood was withdrawn by caudal vein puncture for the determination of red blood cell count, hematocrit, hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and body condition (Kn). The number of erythrocytes varied from 0.880 to 3.940 x 106 μl-1, hematocrit varied from 20.0 to 51.5%, hemoglobin concentration varied from 4.4 to 14.9 g dl-1, MCV varied from 121.8 to 250.0 fL-1, MCHC varied from 15.0 to 35.6 dl g-1, and Kn was 1.00 ± 0.041. Erythrocyte values of Gymnotus spp. herein obtained were within the characteristics presented by other cultured fish species. The data evaluated in this work demonstrated that the tuvira kept in the “bait house” presented good body conditions and healthiness.