The aquatic environment receives many contaminants that can induce damages at the molecular, biochemical, cellular and physiological levels. Centropomus parallelus , an important food resource for local populations, is a predator fish that feeds on small fishes and benthic invertebrates, thus being vulnerable to the bioconcentration and biomagnification processes. This study aimed to evaluate cytogenotoxic responses in erythrocytes from C. parallelus juveniles collected in the Cananéia and São Vicente estuaries, both in winter and in summer. After anesthesia, blood samples were collected by caudal puncture. Blood smears were prepared on glass slides and stained with May-Grünwald-Giemsa dye. Two thousand cells were analyzed per slide (1000x), and nuclear abnormalities (NA) and micronuclei (MN) were scored. The São Vicente sample showed MN and NA frequencies (%/1000 cells) of 0.325 and 3.575, in winter, and of 0.125 and 2.935 in summer respectively; the Cananéia sample showed frequencies of 0.0325 and 0.03, in winter, and of 0.065 and 0.355 in summer, respectively. The rates found in São Vicente were significantly higher than those found in Cananéia, evidencing that the levels of pollution in that estuary were high enough to induce genetic damages.

Foram examinados exemplares de tainha, Mugil platanus, capturados mensalmente na região estuarino-lagunar de Cananéia, SP, entre julho de 1988 e junho de 1989, a fim de verificar a ocorrência de parasitos branquiais. Das 334 tainhas examinadas, apenas quatro não apresentaram nenhum parasito. Nas demais, foram encontrados os seguintes grupos: Trichodina sp., Monogenoidea, Copepoda e Hirudinea. Utilizando os valores de peso total (Wt) e de comprimento total (Lt) de todos os espécimes estudados calculou-se o fator de condição relativo (Kn). Constatou-se que os 118 espécimes infestados por monogenóideos encontravam-se, em média, com peso inferior ao esperado. Os 81 espécimes que tinham, concomitantemente nas brânquias, Trichodina sp., copépodos e monogenóideos apresentaram, em média, peso inferior ao esperado. Os demais espécimes parasitados, assim como os não parasitados, estavam com o peso igual ou acima do esperado. Foi possível constatar que o parasitismo das brânquias por monogenóideos afeta o peso das tainhas, Mugil platanus, da região estuarino-lagunar de Cananéia, SP, especialmente quando co-infestado com Trichodina sp. e copépodos.

This study involved 334 specimens of mullet, Mugil platanus, captured monthly in the estuarine region of Cananéia, São Paulo State, Brazil, from July 1988 to June 1989, and examined for the presence of gill parasites. Parasitological inspections revealed the occurrence of the following groups: Trichodina sp., Monogenoidea, Copepoda, and Hirudinea. Only four mullets were not parasitized. Total weight and total length of all 334 mullet specimens examined were used for adjusting the weight-length relationship curve and calculating the relative condition factor (Kn). The 118 specimens infested with monogenoideans on average had lower weights than expected (Kn < 1.0), and the 81 fish co-infested with Copepoda, Monogenoidea, and Trichodina sp. showed a Kn < 1.0. The other infested and non-infested mullets had a Kn > 1.0. It was possible to infer that gill infestation with monogenoideans alters mullet weight, especially in the presence of co-infestation with Trichodina sp. and copepods.

No período de agosto de 1996 a dezembro de 1997, foram capturados 293 exemplares de dourado, S. maxillosus (Valencienes, 1840), de vários tamanhos, no Rio Mogi-Guaçu, Cachoeira das Emas, para estudos hematológicos. De cada indivíduo foram tomados os dados de peso total (Wt - em gramas) e comprimento total (Lt - em cm). Com as amostras de sangue foram confeccionadas extensões utilizadas na identificação e contagem diferencial de leucócitos (linfócitos, neutrófilos, monócitos, eosinófilos, células granulocíticas especiais e células imaturas). As médias das porcentagens de leucócitos foram analisadas por sexo e por estádio de maturação gonadal (imaturo, em maturação, maduro, esgotado e repouso). Apenas para as células granulocíticas especiais foram encontradas diferenças significativas entre machos e fêmeas. Na análise por estádio de desenvolvimento gonadal somente as fêmeas apresentaram diferenças significativas entre as porcentagens médias dos linfócitos, neutrófilos, monócitos e eosinófilos.

From August, 1996 to December, 1997, 293 of ''dourado'' specimens, Salminus maxillosus (Valencienes, 1840), of various sizes, were caught in Mogi-Guaçu River, Emas Falls, for hematologic studies. Total weight (Wt in g) and length (Lt in cm) were taken for each individual animal. Smears were prepared from blood samples and utilized for differential leukocyte counts (lymphocytes, neutrophils, monocytes, eosinophils, special granulocytic cell and immature cells). The mean percentages of leukocytes were determined according to sex and stage of gonadal maturation (immature, in maturation, mature, spent and resting). Significant differences between male and female occurred only for the special granulocytic cell. In analyzing the leukocyte profile during gonadal development, only female showed significant differences in mean percentages of lymphocytes, neutrophils, monocytes and eosinophils.

The blood cells of fish Salminus maxillosus were studied by means of light microscopy and citochemistry techniques. For citochemistry analisis, we used specific methods for detection of 4 basic macromolecules types, that had different chemistry nature: carbohidrates, lipids, proteins enzimatics and structural. Cells that were differentiated were: erythrocytes, thrombocytes, monophils, lymphocytes, neutrophils type I and II and eosinophils. The thrombocytes, and neutrophils type I and II shows glicogen in the cytoplasm. The neutrophils type II revealed sudanophils and mieloperoxid positive granules and difuse weak reaction for proteins in the cytoplasm. The eosinophils shows strong reaction in cytoplasmic granules.

Las características morfológicas de sangre periférica del pez Salminus maxillosus fueron descritas usando microscopía de luz. Para demostrar el comportamiento citoquímico de las células sanguíneas del pez en estudio, fueron aplicados métodos específicos para la detección de cuatro tipos básicos de componentes macromoleculares, de naturaleza química diferente: carbohidratos, lípidos, proteínas enzimáticas y estructurales. Fueron observados 6 tipos de células: eritrocitos, trombocitos, monocitos, linfocitos, neutrófilos de los tipos I y II y eosinófilos. Los trombocitos y los neutrófilos de los tipos I y II presentaron glucógeno en el citoplasma. Los neutrófilos del tipo II presentan gránulos sudanófilos y mieloperoxidasa. Además presentan, reacción difusa intensa para proteínas en el citoplasma. Los eosinófilos muestran reacción intensa en sus gránulos.