Parâmetros bioquímicos e hormonais durante o ciclo reprodutivo de Vanellus chilensis (Aves, Charadriiformes)

• Ano de defesa: 2011
• Autor(a) principal: Pöerschke, Filipe
• Orientador(a): Oliveira, Guendalina Turcato
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul; Porto Alegre
• Palavras-chave em Português: ZOOLOGIA; AVES; ECOFISIOLOGIA
• Link de acesso: http://hdl.handle.net/10923/5425

Vanellus chilensis is highly territorial and aggressive during the breeding period, forming groups of three to four individuals, is one of the most common species in the urban area of Porto Alegre (Fontana, 2004). There are a large number of papers on urban birds, but no using ecophysiology practices in Brazil. This study aimed to analyze in two locations, with a rural character and the other inserted into an urban center, the plasmatic variations in: corticosterone, testosterone and metabolites. The animals were always caught at night, blood samples and data molt were collected. The metabolites (glucose, total lipids, triglycerides, cholesterol, HDL, LDL, VLDL, glycerol, uric acid and total protein) were quantified in plasma using spectrophotometry; corticosterone and testosterone determined by radioimmunoassay. In the juveniles of the Area 1 we verified a predominance of females (2. 7 females: 1 male) in area 2 this relationship is reversed (2 males: 1 female), which seems to relate to higher levels of testosterone and lower corticosterone observed in females (period 1) in Area 2. Comparing the areas of capture, the highest levels of plasma corticosterone were observed in the juveniles of the Area 2 suggesting a greater environmental stress that may be related to a higher predation pressure and/or intense activity and human presence and/or intraspecific competition. In the juveniles, throughout the study, the two localities studied we not observe any variations in the levels of plasmatic metabolites, except for triglycerides of the juveniles in Area 2.However, when comparing the Area 1 with Area 2 a differential behavior is observed throughout the development of juveniles in triglycerides, HDL, VLDL and total proteins; the remaining parameters (glucose, total lipids, cholesterol, LDL, glycerol and uric acid) do not show a differential behavior. In adults we found differences in corticosterone levels in females from Area 2, but in both sexes and localities, we observed a tendency of reduction in hormone levels during the reproductive period. The results showed differences in testosterone levels between males and females from Area 1 when compared with the Area 2 during the study period; however the periods of the breeding season in each location showed differences only in females.In Area 1, the breeding season was about 2 times lower than in Area 2 and the females showed a significant increase of all plasmatic metabolites, with the exception of glycerol, already the males show a rise in glucose, cholesterol, HDL and LDL mainly in period 3. In Area 1, we observe a gradual increase glucose levels in plasma reaching maximal values in males and females in period 3, a period characterized by the presence of defensive behaviors and parental care, and also, the period before the molt of flight feathers. In the Area 2 was not observed variation in levels of plasmatic metabolites, except for glucose in males and triglycerides, glycerol and uric acid in both sexes. This pattern maybe can be explained by greater availability of food and/or less competition and/or increased investment in search of food. The results suggest that Vanellus chilensis capture in Area 2 present an adaptive pattern in relation to human action and relationships of abiotic and biotic of this area. In the final of this work can be concluded that there were differences between the two areas of study, and levels of corticosterone, testosterone, plasmatic metabolites and duration of breeding season are influenced by human action.