Natural breeding conditions and artificial increases in testosterone have opposite effects on the brains of adult male songbirds: a meta-analysis.

Exogenous Testosterone, Finasteride and Castration Effects on Testosterone, Insulin, Zinc and Chromium in Adult Male Rats

Background: Although effects of trace elements on secretion of sex steroids and insulin have been studied, the effects of these hormones on serum level of trace elements have been rarely investigated. The aim of the present study was to evaluate the effect of testosterone and finasteride administration and castration on serum levels of testosterone, insulin, zinc and chromium. Methods: Male adu...

P-84: Blastocysts Production and Collection in Albino Hamster Using Superovulation and Intrauterine Artificial Insemination in Non-Breeding Season

Background: Due to the seasonality reproduction of albino hamster (April to October in the Northern Hemisphere) and the need to produce blastocysts for research applications, producing and collecting blastocysts by natural mating in non-breeding season is complex in this species. In the present study in vivo blastocysts production and collection using super-ovulation and intrauterine inseminati...

Effects of aflatoxin B1 on profiles of gonadotropic (FSH and LH), steroid (testosterone and 17β-estradiol) and prolactin hormones in adult male rat

Aflatoxins (AFs) are natural contaminants of feed and feedstuffs, thus the study of the noxious effects ofthese agents on the male reproductive system is of outstanding importance. Our aim for this study is theevaluation of the effects of oral administration of aflatoxin B1 on the reproductive hormonal changes in adult male rat. Twenty eight Wistar strain male rats were selected for this study....

Hatching late in the season requires flexibility in the timing of song learning.

Most songbirds learn their songs from adult tutors, who can be their father or other male conspecifics. However, the variables that control song learning in a natural social context are largely unknown. We investigated whether the time of hatching of male domesticated canaries has an impact on their song development and on the neuroendocrine parameters of the song control system. Average age di...

The Effects of Lead Acetate on Sexual Behavior and the Level of Testosterone in Adult Male Rats