Wild animals are brought into captivity for many reasons. However, unlike laboratory-bred animals, wild caught animals often respond to the dramatic shift in their environment with physiological changes in the stress and reproductive pathways. Using wild-caught male and female house sparrows (Passer domesticus) we examined how time in captivity affects the expression of reproductive and stress-associated genes in the brain, specifically, the hypothalamus. We quantified relative mRNA expression of a neurohormone involved in the stress response (corticotropin releasing hormone [CRH]), a hypothalamic inhibitor of reproduction (gonadotropin inhibitory hormone [GnIH]), and the glucocorticoid receptor (GR), which is important in terminating the stress response. To understand potential shifts at the cellular level, we also examined the presence of hypothalamic GnIH (GnIH-ir) using immunohistochemistry. We hypothesized that expression of these genes and the abundance of cells immunoreactive for GnIH would change in response to time in captivity as compared to free-living individuals. We found that GR mRNA expression and GnIH-ir cell abundance increased after 24 and 45 days in captivity, as compared to wild-caught birds. At 66 days in captivity, GR expression and GnIH cell abundance did not differ from wild-caught birds, suggesting birds had acclimated to captivity. Evaluation of CRH and GnIH mRNA expression yielded similar trends, though they were not statistically significant. In addition, although neuroendocrine factors appeared to acclimate to captivity, a previous study indicated that corticosterone release and immune responses of these same birds did not acclimate to captivity, suggesting that neuroendocrine endpoints may adapt more rapidly to captivity than downstream physiological measures. These data expand our understanding of the physiological shifts occurring when wild animals are brought into captivity.

由于多种原因，野生动物被圈养。但是，与实验室饲养的动物不同，野外捕获的动物通常通过压力和生殖途径的生理变化来应对其环境的急剧变化。使用野生雌性和麻雀（Passer domesticus），我们研究了人工饲养的时间如何影响大脑（尤其是下丘脑）中生殖和应激相关基因的表达。我们量化了参与应激反应（促肾上腺皮质激素释放激素[CRH]），下丘脑繁殖抑制因子（促性腺激素抑制激素[GnIH]）和糖皮质激素受体（GR）的神经激素的相对mRNA表达，这对于终止神经营养激素很重要。压力反应。为了了解细胞水平上的潜在变化，我们还使用免疫组织化学检查了下丘脑GnIH（GnIH-ir）的存在。我们假设，与自由生活的个体相比，这些基因的表达和对GnIH免疫反应的细胞数量会随着时间的变化而变化。我们发现，与野生鸟类相比，圈养24和45天后GR mRNA表达和GnIH-ir细胞丰度增加。圈养66天后，GR表达和GnIH细胞丰度与野生鸟类没有差异，这表明鸟类已经适应了圈养。CRH和GnIH mRNA表达的评估产生了相似的趋势，尽管它们在统计学上并不显着。此外，尽管神经内分泌因素似乎适应了人工饲养，但先前的研究表明，这些相同鸟类的皮质酮释放和免疫反应并不适应人工饲养，这表明神经内分泌终点可能比下游的生理指标更快地适应人工饲养。这些数据扩大了我们对野生动物被圈养时发生的生理变化的理解。