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Objetive . Evaluation of hematological and biochemical parameters of culture channel catfish (Ictalurus punctatus) under acute stress by management and capture practice. Materials and methods . Fish (200 g mean) were maintained in culture tanks and divided in two treatments, in duplicate, (n=15x2x2=60 fishes). Thirty catfish were exposed for 5 min to acute stress (TE) by management and capture practice, while other group not (control group, TnE). 10 fish for treatment were collected at 0, 6, and 24 h post-stress for blood collection, where TnE fishes were anesthetized along work. Complete blood count (manual method) and blood biochemical (spectrophotometry) of fish samples were evaluated and their results were analyzed using a Student's t-distribution. Results . The erythrocytes, hematocrit, hemoglobin and glucose level of TE animals was significantly higher (p<0.05) at 6 h post-stress, in comparison of TnE. Immune cells in fish TE decreased at 6 and 24 h post-stress, where leukocytes and lymphocytes were significantly lower that TnE (p<0.05) at 24 h post-stress. Other evaluated parameters did not show significant differences along this study. Conclusions . Those results suggest that several hematological and blood biochemical parameters in fish changed by acute stress generated by management and capture practice., RESUMEN Objetivo . Evaluar los efectos del estrés agudo debido al manejo y captura sobre los parámetros hematológicos y bioquímicos en bagre de canal (Ictalurus punctatus) bajo cultivo. Materiales y métodos . Los peces (200 g promedio) fueron mantenidos en tanques de cultivo y divididos en dos tratamientos, por duplicado, (n= 15 x 2 x 2 = 60 peces). Treinta bagres fueron expuestos por 5 min a estrés agudo (TE) por manejo y captura, mientras que otro grupo no (grupo control, TnE). Diez peces de cada tratamiento fueron colectados a las 0, 6, y 24 h post-estrés para la extracción de sangre, los bagres del TnE fueron anestesiados durante su manejo y captura. Se evaluó el hemograma (método manual) y bioquímica sanguínea (espectrofotometría). Los resultados fueron analizados mediante la prueba de t student. Resultados . El contenido de eritrocitos, hematocrito, hemoglobina y glucosa de los animales TE fue significativamente mayor (p<0.05) a las 6 h post-estrés en comparación de TnE. Las células inmune en peces TE disminuyeron a las 6 y 24 h post-estrés, siendo leucocitos y linfocitos significativamente menores en el TnE (p<0.05) a las 24 h post-estrés. Otros parámetros evaluados no presentaron diferencias significativas en lo largo del estudio. Conclusiones . Los resultados sugieren que varios indicadores hematológicos y bioquímica sanguínea en los peces son alterados por el estrés agudo ocasionado por manejo y captura.

The presence of diseases caused by virus and bacteria pose a threat to the capture and commercialization of shrimp, and may cause significant economic damage. Nocturnal monthly sampling were conducted to detect the presence of IHHNV, WSSV, and NHP in San Andres Lagoon in Tamaulipas, Mexico, an important coastal ecosystem due to its shrimp fishery and the existence of shrimp farms in the area. Polymerase chain reaction (PCR) analysis in the shrimp tissue did not detect the presence of IHHNV, however, WSSV was detected, as well as NHP during July and August, when low salinities and high temperatures were recorded.

Copepods are a common component of the ectoparasitic assemblages of all kinds of fish, from all environments and ecosystems (Boxshall & Halsey, 2004). The family Ergasilidae comprises the most common parasites of freshwater fish and the highest diversity is found in the genus Ergasilus Von Nordmann, 1832, with more than 180 nominal species (El-Rashidy & Boxshall, 2001; Montú & Boxshall, 2002; Boxshall & Halsey, 2004). Ergasilus has a worldwide distribution except in Antarctica (Boxshall & Defaye, 2008; Thatcher & Brasil-Sato, 2008), inhabiting estuarine and freshwater ecosystems. Only the females are found on their fish hosts, whereas the males are free-living in the zooplankton (Amado et al., 1995; Suárez-Morales & Santana-Piñeros, 2008; Thatcher & Brasil-Sato, 2008).