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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Seasonal Patterns of Variation in Steroid Plasma Levels and Immune Parameters in Anurans from Brazilian Semiarid Area

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Madelaire, Carla Bonetti ; Sokolova, Inna ; Gomes, Fernando Ribeiro
Total Authors: 3
Document type: Journal article
Source: PHYSIOLOGICAL AND BIOCHEMICAL ZOOLOGY; v. 90, n. 4, p. 415-433, JUL-AUG 2017.
Web of Science Citations: 7

Elevated androgens and glucocorticoids displayed by males during the reproductive season have been proposed to mediate a possible trade-off between reproduction and immunocompetence. Anurans living in arid and semiarid environments display a strong seasonal reproduction, which could accentuate the variation in physiological, immunological, and behavioral parameters. We studied covariation between steroid plasma levels, morphometric variables associated with body condition and immunity, leukocyte profile, parasite load, and response to an immunological challenge across different phases of the annual life-history cycle of three anuran species from a Brazilian semiarid area. Our results showed a seasonal pattern of covariation among leukocyte parameters, kidney mass, and steroid plasma levels, with higher values measured during the reproductive season, particularly when males were sampled during calling activity. Moreover, these anurans showed a stronger response to an immunological challenge during the reproductive period. The immunosuppression during the dry period was particularly evident for the species that aestivate, indicating that the availability of energetic resources might be an important factor determining seasonal variation in inflammatory response. Intensity of the helminth infection was associated with eosinophil count but showed a more complex pattern with regard to androgens levels. These data emphasize that variations in the intensity of helminth infection might be more closely related to specific aspects of the immune response than to the general seasonal patterns of variation in steroid plasma levels, total circulating leukocytes, and inflammatory response. (AU)

FAPESP's process: 11/03030-2 - Sazonal relationship between testosterone, reprodution, immunocompetence and endoparasites in anuran amphibians of caatinga
Grantee:Carla Bonetti Madelaire
Support Opportunities: Scholarships in Brazil - Master
FAPESP's process: 14/50643-8 - Effects of extreme seasonality on metabolism and immunity of amphibians in a tropical semi-arid zone
Grantee:Fernando Ribeiro Gomes
Support Opportunities: Regular Research Grants