Mentol como anestésico para dourado (Salminus brasiliensis)

Different levels of menthol as an anesthetic for dourado (Salminus brasiliensis) were evaluated in this study. Fish (n=32) with average weight of 194.13 +/- 9.06 g and total mean length of 25.30 +/- 0.90 cm were separated in four groups composed of 8 individuals. Each group was submitted to different menthol concentrations: 60, 90, 120 and 150 mg L(-1). Total induction time was analyzed by polynomial regression and other parameters by Tukey's test. All experimental fish exposed to different concentrations of menthol reached deep anesthesia stage without mortality. It was observed a negative linear effect (P<0.05) for total induction time. The longest recovery time (172.60 s) was observed for dourado treated with 120 mg. L(-1), which differed (P<0.05) from the 90 mg.L(-1) treatment (122.03 s). All levels evaluated in this study were safe and effective. A concentration of 60 mg L(-1) for dourado is suggested based on lower cost and adequate induction and recovery time responses.

Trichodina heterodentata (Ciliophora: Trichodinidae): a new parasite for Piaractus mesopotamicus (Pisces: Characidae)

Trichodinids are mobile peritrichous ciliated protozoa, and widely known as ectocommensals and/or parasites of fish and other aquatic organisms. Little is known about the trichodinid fauna in Brazilian fish. This study reports Trichodina heterodentata Duncan, 1977 as a new parasite for freshwater fish Piaractus mesopotamicus Holmberg, 1887. This is the first record of this trichodinid in southeastern Brazil. Fifty specimens impregnated with 2% silver nitrate and another fifty stained with Giemsa were used for morphometry on the taxonomic characteristics. T. heterodentata in this study is medium size, with a disc-shaped body measuring 49.0 to 61.0 mu m, parasitizing the skin, fins and gills of pacu. Measurement comparisons between the present material and other records from different countries are presented.

Metacromasia para identificação de basófilos sanguíneos em surubim híbrido: contribuição metodológica

Padua S.B. & Ishikawa M.M. [Metachromasia for blood basophils identification in hybrid surubim catfish: methodological contribution]. Metacromasia para identificacao de basofilos sanguineos em surubim hibrido: contribuicao metodologica. Revista Brasileira de Medicina Veterinaria, 33(3):147-150, 2011. Centro de Aquicultura da Unesp/Jaboticabal Rod. Paulo Donato Castellane, s/n Bairro Rural, Jaboticabal, 14884-900, SP. Brasil. E-mail: santiagopadua@live.comDifferent protocols of fixation and hydrolysis of blood smears of hybrid surubim catfish for metachromasia to marking blood basophils were evaluated. For this reason, methanol, acid-alcohol and formalin vapor were tested as fixatives. For hydrolysis of blood smears, HCl, citric acid and 2-Mercaptoethanol + Urea + NaCl solutions was evaluated. After procedures, the blood smears was stained with toluidine blue (0.025%) diluted in McIlvaine buffer (pH 4). The different protocols for fixation and hydrolysis of blood smears for metachromasia influenced the quality of the reaction. Hydrolysis with 2-Mercaptoethanol + Urea + NaCl solutions provided negative results when using methanol and acid-alcohol as fixatives. The fixation with acid-alcohol associated with citric acid hydrolysis provides highest quality reason.

Identificação morfológica de organismos semelhantes à anaplasmataceae em monócitos de surubim híbrido (Pseudoplatystoma reticulatum x P. corruscans) – relato de caso

The aim of this study was to report the occurrence of Anaplasmataceae-like organisms in monocytes from the hybrid surubim catfish. During the hematological evaluation of fish infected by Pseudomonas sp. in a fish farm located in the State of Mato Grosso do Sul we observed into the monocytes the presence of numerous pleomorphic inclusions of various sizes, rough in appearance which presented basophilic staining. These inclusions were similar to elementary bodies, initial bodies and morule of the bacteria from Anaplasmataceae family, often diagnosed in domestic mammals. This is the first report of its occurrence possibly belonging to the family of Anaplasmataceae in cultured fish in Brazil. Additional studies are necessary for molecular characterization of this bacteria, pathogenic potential, life cycle and impact on the intensive production of fish.