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| Tsuzuki,M.Y.; Ogawa,K.; Strüssmann,C.A.; Maita,M.; Takashima,F.; Melo,C.M.R.. |
| The role of cortisol on the osmoregulation of pejerrey Odontesthes bonariensis at different salinities was investigated in adult fish injected with 0.7mg hydrocortisone per 100g body weight of fish, and transferred to 0, 5 and 20ppt of NaCl. Blood cortisol was 566ng/ml at the beginning of the experiment (0h) but surged to 1250ng/ml within 3h in cortisol-injected fish. Cortisol levels were influenced not only by treatment but also by time, being higher at 3h compared to 24h. Salinity level, time of exposure and their interaction, but not cortisol treatment, significantly affected plasma osmolality and the concentration of ions Cl- and Na+. This study showed that exogenous cortisol does not seem to play a significant role on the regulation of plasma... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pejerrey; Odontesthes bonariensis; Cortisol; Osmoregulation; Salinity. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352007000500030 |
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| Santos,R.S.; Roumbedakis,K.; Marengoni,N.G.; Takahashi,H.K.; Pimenta,F.D.A.; Melo,C.M.R.; Martins,M.L.. |
| The occurrence of proteocephalid cestodes in tucunaré Cichla sp., captured monthly, between August 2000 and August 2001, in Paraná River, Presidente Epitácio, SP, was evaluated. From 128 specimens, 71 (55.6%) were parasitized by Proteocephalus macrophallus (Diesing, 1850) and/or P. microscopicus (Woodland, 1935). Total mean abundance and intensity were 157.08 and 223.41, respectively. The highest prevalence (90%) mean abundance (1,122.4) and intensity indexes (1,247.11) occurred in February 2001, while in September 2000 there were no observed animals infected by cestodes. No relationship between the sex of the host and parasitological indexes was found. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish; Tucunare; Parasitism; Proteocephalidae; Paraná River. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352011000300008 |
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