Hormonal correlations at transition from reproduction to molting in an annual life cycle of Humboldt penguins (Spheniscus humboldti)
To understand the hormonal mechanism behind a unique strategy of breeding and molting in Humboldt penguins, six pairs of captive Humboldt penguins kept in an outdoor open display pen were observed and blood collected weekly for a year. They all molted between the middle of June and the middle of August within 10 days except […]
Reproductive and thyroid hormone profiles in captive Western fence lizards (Sceloporus occidentalis) after a period of brumation
Abstract 10.1002/zoo.20159.abs Seasonal fluctuation in serum concentrations of sex steroid (testosterone [T] and 17β-estradiol [E2]) and thyroid (triiodothyronine [T3] and thyroxine [T4]) hormones was determined in captive Western fence lizards (Sceloporus occidentalis). Samples were collected from male and female breeding pairs weekly for a 4-month period after their emergence from artificial brumation. Circulating levels of […]