Abstract：
Androgens are produced in both sexes. In females produced by the adrenal gland and the ovaries they play a crucial role in regulating ovarian function, estrogen synthesis and follicular growth. Age leads to a reduction in androgen concentrations, although, at present, these mechanisms are not elucidated in mares. The objective of this study was to evaluate the concentrations of testosterone (T), androstenedione (A4) and dehydroepiandrosterone (DHEA) in mares of different ages. Blood samples were drawn from seventy cyclic Spanish Purebred mares belonging to five age groups: 3-5 years, 6-9 years, 10-13 years, 14-16 years and > 16 years. The concentrations of T, A4 and DHEA were determined by EIA, validated specifically for horses. Mares aged 3-5, 6-9 and 10-13 years had higher T concentrations (P < 0.05) than mares aged >16 years, and mares aged 6-9 years had also higher concentrations than those 14-16 years old (P < 0.05). A4 concentrations were lower (P < 0.05) in mares >16 years old when compared with those of other age groups. DHEA concentrations were lower (P < 0.05) in mares 14-16 years and > 16 years old when compared with those of other age groups. DHEA was positively correlated with T (r = 0.61; P < 0.05) and A4 (r = 0.51; P < 0.05). Age induces reduction in androgens\' synthesis in physiologically cyclic Spanish Purebred mares. These physiological variations must be duly considered for a correct and objective interpretation of the analytical data.
摘要：
雄激素在两性中均产生。在由肾上腺和卵巢产生的雌性中，它们在调节卵巢功能中起着至关重要的作用，雌激素合成和卵泡生长。年龄导致雄激素浓度降低，虽然,目前,这些机制在母马中没有阐明。这项研究的目的是评估睾酮（T）的浓度，不同年龄母马的雄烯二酮（A4）和脱氢表雄酮（DHEA）。血液样本是从属于五个年龄组的70个周期的西班牙纯种母马中抽取的：3-5岁，6-9年,10-13年,14-16年和>16年。T的浓度,A4和DHEA通过EIA确定，专门为马匹验证。3-5、6-9和10-13岁母马的T浓度高于16岁以上母马（P<0.05）。6-9岁的母马也高于14-16岁的母马（P<0.05）。与其他年龄组相比，>16岁的母马中A4浓度较低（P<0.05）。与其他年龄组相比，14-16岁和>16岁母马的DHEA浓度较低（P<0.05）。DHEA与T(r=0.61;P<0.05)、A4(r=0.51;P<0.05)呈正相关。年龄诱导生理循环西班牙纯种母马中雄激素合成减少。为了正确和客观地解释分析数据，必须适当考虑这些生理变化。
