Excreção de nitrogênio em embriões de iguana Iguana iguana (Reptilia; Squamata) / Nitrogen excretion in the green iguana (Iguana iguana) embryos (Reptilia; Squamata)

AUTOR(ES)
FONTE

IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia

DATA DE PUBLICAÇÃO

18/05/2012

RESUMO

A Table of embryonic stages can be used to detect similarities and differences in developmental features between groups and as a tool for studies based on embryonic phase. In this study, eggs of the lizard Iguana iguana were used to elaborate a staging table and to determine the nitrogen excretion pattern during the development. Iguana is a convenient model for having a large clutch of large eggs, allowing an easy handling and a good number of replicates. After oviposition embryonic stages were determined during which urea was the main nitrogen waste. Although iguana is the first lizard studied, the ureotelic pattern is common among the majority of reptilian species so far studied The pergaminaceous shell allows that the eggs double in mass due to water absorption, and the mechanism and how the egg deals with dilution and resultant osmolarity is an interesting issue for future works and comparisons with species of rigid eggshells. There is evidence of heterocronic development of the limbs and the development of iguana is similar to the lizard Anolis sagrei, also from the clade Iguania. Further studies on lizard evelopment are required and the use of similar morphological approach to facilitate comparisons of embryonic events

ASSUNTO(S)

desenvolvimento embrionário embryonic development répteis reptiles urea uréia

ACESSO AO ARTIGO

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