小熊猫繁殖周期血清雌二醇和孕酮含量变化

为研究小熊猫繁殖周期血清雌二醇、孕酮含量变化规律,采用化学发光免疫分析法连续16次测定了2只成体雌性小熊猫血清雌二醇和孕酮含量变化,历经发情间期、发情期和两次妊娠期;连续9次测定了7只小熊猫妊娠期的孕酮含量变化。结果：（1）发情间期,小熊猫血清雌二醇的水平一直维持在低水平（基础水平）,进入发情前期,血清雌二醇水平明显升高,在发情期一直维持高水平,配种后迅速降至基础水平;（2）小熊猫血清孕酮含量在发情间期和发情期均维持在较低水平,直至发情期过后才出现升高,在妊娠期一直维持高水平,峰值出现在5月;（3）发情的小熊猫不论妊娠与否,在妊娠期内血清孕酮含量均维持在高水平。研究表明：小熊猫血清雌二醇、孕酮含量变化能直接反映其繁殖规律,雌二醇对启动雌性小熊猫季节性繁殖起重要作用;在妊娠期内小熊猫血清孕酮含量升高不能作为判断小熊猫妊娠的标准;雌性小熊猫在妊娠期有假孕现象。     

雌性川金丝猴的邀配行为与尿液雌二醇水平的关系

2001年10～12月及2002年9月～11月,我们对上海野生动物园一群半散养条件下的川金丝猴进行了研究,记录了群体内的4只成年雌猴的邀配行为,同时收集了观察对象的晨尿,利用放射免疫法测定其中的雌二醇含量。结果显示,在未受孕的月经周期内,雌猴的邀配行为集中在雌二醇高峰前后,雌猴在卵泡期和黄体期邀配频次显著下降,说明邀配行为受雌二醇水平的调控。同一群体内不同个体的月经周期并不同步,邀配高峰互不重叠,这可能是雌猴避免相互竞争产生的结果。利用雌二醇测定结果推断受孕日期,发现进入妊娠期后雌猴仍然频繁地向雄猴邀配,并得到雄猴的响应。妊娠期内的雌二醇水平虽有波动,但都高于月经周期内排卵前的雌二醇高峰,邀配频次与雌二醇水平没有明显的相关性,因此这一时期的邀配行为不能归结为激素作用的结果,它们应该具有其它社会功能[动物学报49(6)：736～741,2003]。     

雌性大熊猫发情期与妊娠期尿液性激素的变化

用放射免疫法测定了两头雌性大熊猫发情期尿中雌二醇与孕酮含量及妊娠期尿中孕酮含量的变化。发情期开始,雌二醇量逐渐升高,在发情高潮期达高峰值。孕酮量则在发情高潮期下降,在发情后期上升。在发情高潮期雌二醇出现高峰的当日和次日配种,获致妊娠产仔。妊娠期尿中孕酮含量的变化特点是:在妊娠早期与晚期升高,晚期最高,妊娠中期停滞在低水平上波动,分娩前孕酮值迅速下降。     

雌性大熊猫发情期尿中17β—雌二醇与孕酮水平的变化及其与配种的关系

本文用放射免疫法测定了3头雌性大熊猫(Ailuropoda melanoleuca)发情期尿中17β-雌二醇与孕酮水平的变化。大熊猫的发情行为与尿中17β-雌二醇浓度的变化密切相关。发情期中,随着孕酮水平下降的同时雌二醇水平却迅速上升并达峰值(28.2—65.5毫微克/毫克肌酐),然后再下降到基础水平。性活动最强烈的日期发生在17β-雌二醇最高峰值的当天或峰后一天。在雌二醇峰后,尿中孕酮水平逐步升高,发情后期的孕酮平均值显著高于发情前期(P<0.01)。本实验中,3头大熊猫均妊娠,说明自然交配或人工授精的适宜时间可根据雌性大熊猫尿中17β-雌二醇的监测予以确定。     

大熊猫雌性个体发情期生殖内分沁变化的研究

本文首次报道了用黄体生成素的生物测定法测定大熊猫发情期黄体生成素的生物活性与雌二醇、孕酮的关系。雌性大熊猫在发情高潮后两天,尿中黄体生成素的生物活性与雌二醇同时出现峰值,并与雄性变配。随后尿中孕酮浓度迅速增长,其浓度远远大于发情前期的水平。生殖内分泌的变化证实:雌性大熊猫在发情期中有成熟的卵子排出。     

蓝狐发情期及妊娠期血清五种 生殖激素含量变化

为探究发情期及妊娠期雌性蓝狐(Alopex lagopus)生殖激素的变化规律,选取11只繁殖期雌性蓝狐,采用放射免疫法(RIA)测定血清中雌二醇(E2)、促黄体生成素(LH)、促卵泡素(FSH)、孕酮(P)以及催乳素(PRL)的含量。结果表明,促卵泡素和促黄体生成素在发情期及妊娠期血清中浓度一直处于较稳定水平,并呈波动式分泌,最大值分别为(2.18±0.69)U/L和(8.82±1.83)U/L,同种激素不同检测日期数据两两比较差异不显著(P> 0.05);雌二醇在发情期和妊娠期血清中浓度亦处于较稳定水平,最大值出现在发情第1天,为(27.73±23.19)ng/L,数据两两比较差异亦不显著(P> 0.05);孕酮在发情期维持较高水平,最大值在发情第3天,为(2.41±1.35)μg/L,之后在妊娠期持续下降,分娩当天达到最低点,为(0.13±0.14)μg/L,数据两两比较差异显著(P <0.05);催乳素在发情期先下降,最低值为(0.15±0.04)U/L,第3天开始升高,并在妊娠期保持较高水平,到分娩时维持最高(0.21±0.05)U/L,数据两两比较差异不显著(P> 0.05)。初步探索了5种激素含量在发情和妊娠期间的动态变化,为养殖蓝狐的生殖生理提供参考数据。     

秦岭野生雌性川金丝猴粪便睾酮水平与邀配频次的季节性变化

为研究野生雌性川金丝猴(Rhinopithecus roxellana)不同季节体内睾酮水平与性行为频次的变化及二者的关系,我们以秦岭一野生川金丝猴种群为研究对象,通过长时间连续跟踪观察,完成了该种群中所有87只金丝猴的个体识别。用无损伤取样法采集了三只成年雌性川金丝猴不同季节的粪样,对粪样中的睾酮进行抽提测定,同时对采样个体的性行为进行记录。结果显示:1)成年雌猴在交配盛期与非交配盛期,粪样中睾酮水平均呈明显的周期性波动,交配盛期时睾酮水平的变化周期为24.56 d±4.07 d,非交配盛期时为43.67 d±2.89 d,显著长于交配盛期;2)成年雌猴在交配盛期的粪样睾酮水平为2.85 ng±1.12 ng/g,邀配频次为0.98±1.04次/d,非交配盛期时睾酮水平为1.71 ng±0.77 ng/g,邀配频次为0.28±0.53次/d,与交配盛期相比,非交配盛期的睾酮水平和邀配频次均明显降低;3)交配盛期各成年雌猴的粪样睾酮水平与邀配频次均有较显著的正相关关系(相关系数分别为0.631、0.683和0.659),而在非交配盛期这种相关关系并不存在(相关系数分别为0.091、0.493和0.205)。本研究表明,成年雌性川金丝猴体内睾酮水平、睾酮水平变化周期及邀配行为频次均具有明显的季节性差异,这种季节性差异可能是川金丝猴行季节性繁殖的内在原因和外在表现之一。本研究亦表明交配盛期雌猴的性行为频次在一定程度上可能受体内睾酮水平的控制,而在非交配盛期这种控制作用较弱。     

白马雪山自然保护区响古箐滇金丝猴的交配行为

灵长类交配模式是灵长类社群结构和婚配制度的重要表征之一,其研究有助于了解灵长类社群结构和两性交配策略。2013年11月至2014年10月,我们对云南白马雪山国家级自然保护区一人工辅助投食滇金丝猴群进行了观察研究,采用焦点动物取样法和全事件记录法收集了雌雄个体交配相关的行为数据,主要包括邀配对象、交配过程、持续时间和回合数,以及参与交配的雌雄对在交配结束后的相互理毛的持续时间和回合数。研究结果表明:研究群滇金丝猴全年均有交配行为,交配高峰期在7-9月,两性参与交配的积极性和对季节变化的响应不同;交配主要由雌性通过邀配发动(76%),交配高峰期也是雌性邀配的高峰期;雄性爬跨频次(年均0.43次/月,n=5)和射精爬跨比(年均19%,n=5)在全年无显著变化。交配行为发生的典型表现为:雌性通过小跑或跳跃进入雄性视线范围内,爬伏呈臀向雄性邀配;雌猴爬伏时离雄猴的远近距离不同(1 m vs.2-5 m:69%vs.31%)会影响其邀配成功率(1 m vs.2-5 m:68%vs.40%);若一次邀配失败,雌猴可能会连续爬伏邀配(最多4次),连续多次邀配的成功率显著高于单次邀配(79%vs.52%)。交配结束后雌性会主动为雄性理毛,但雌性主动理毛与交配是否射精无关。     

笼养雌性短尾猴月经周期及性行为

在多雄多雌的灵长类社会中,成年雌雄个体的性行为并不局限于雌性受孕期,但仍认为性行为在受孕期最为活跃。对于雌性隐藏发情的灵长类物种,雌雄个体的性行为与雌性月经周期的相关性尚不清楚。本研究以短尾猴(Macaca thibetana)为研究对象,研究雌性隐藏发情灵长类的性行为与月经周期阶段的关系。在短尾猴繁殖季节,从2019年10月2日至2020年1月14日连续采集了安徽省铜陵市动物园6只成年雌性短尾猴的490份粪便样本,采用放射免疫分析法检测粪便中雌二醇激素的浓度,并用焦点动物取样法和行为取样法采集目标个体(4只雌性、4只雄性)的性行为数据。本研究利用Spearman相关系数检验雌激素与性行为的相关性;独立样本T检验分析雌性短尾猴发情的邀配性指标(雌性呈臀行为)、吸引性指标(雄性性检查行为)和交配行为在月经周期三个阶段(受孕期前:受孕期前的5 d;受孕期:最有可能排卵的2 d加上精子能在雌性生殖道中存活的3 d;受孕期后:受孕期后的5 d)的分布差异性。结果表明,雌性短尾猴的雌二醇浓度在繁殖季节呈现周期性波动,周期长度为(31.1±1.8)d(n=7,范围23～37 d);同时在月经周期内,雌二醇浓度与雌性呈臀行为呈显著负相关(r=﹣0.616,n=15,P=0.015),而与交配行为和雄性性检查行为均无显著相关性;雌性呈臀行为的平均频次主要集中在受孕期前(T=﹣1.215,df=12,P=0.044);交配行为和雄性性检查行为在月经周期的三个阶段无显著性差异。短尾猴的性行为并没有集中在雌性的受孕期,说明雌激素对短尾猴的性行为无严格控制作用,且雄性短尾猴无法准确识别雌性的受孕期。     

小熊猫妊娠期粪便中孕酮、雌二醇的水平变化

2000年3—8月在成都动物园和成都大熊猫繁育研究基地,用放射免疫分析法测定了6只雌性小熊猫粪样中孕酮（P）和雌二醇（E2）的水平变化,同时对其繁殖行为进行了观察。研究结果表明,交配后的雌体粪样中E2浓度下降至基础水平,P浓度在30d后上升至150ng／g以上;怀孕雌体在妊娠期粪样中P水平在200ng／g以上,P峰值可以达500ng／g以上;假妊娠者粪样中P水平一般不超过150ng／g,P峰值在200ng／g以下;雌体产前半个月孕酮迅速下降,E2缓慢上升,产后P保持在基础水平。这意味着可通过测定粪便中P水平进行早孕诊断、产期预测和真假妊娠判断。根据行为观察和粪样激素分析可知,雌兽妊娠期为123—128d（X=124,N=5）,产仔率为1．8／胎（N=5）。     

Does Estradiol Modulate Sexual Solicitations in Female Rhinopithecus roxellana?

Studies of the relationship between sexual behavior and reproductive endocrinology in females offer critical insight into sexual selection, mate choice, and female reproductive strategies in primates. We examine the relationship between sexual solicitations and urinary estradiol in female Sichuan golden monkeys (Rhinopithecus roxellana) living under semiwild conditions at the Shanghai Wild Animal Park, China. We collected data on the frequency of sexual solicitations and urinary samples on 4 adult females during 2 mating seasons. We determined urinary estradiol levels via radioimmunoassay. Our results indicate that during the ovarian cycle, solicitation focused on the periovulatory period around the estradiol peak. The frequency of female solicitations rose to a peak after the peak of estradiol level, suggesting that ovarian steroids modulate sexual behavior during the fertile phase of the ovarian cycle. We also found that females frequently solicited matings during pregnancy, most of which the α male accepted and that resulted in copulations. During pregnancy, however, there was no obvious relationship between sexual solicitation and urinary estradiol. We conclude that in Rhinopithecus roxallana, sexual behavior and estradiol production do not strictly correlate during different parts of the reproductive cycle. We discuss additional relationships between social interactions, dominance, sexual behavior, and endocrine function.     

圈养林麝社会等级与粪样类固醇激素水平的关系

动物社群的社会等级可对个体的资源分配、社群稳定及个体的行为对策产生重要影响,圈养动物的类固醇激素水平与饲养管理有关,可反映动物的社群紧张水平。深入理解圈养动物的社会等级与其类固醇激素水平的关系是进行濒危动物迁地保育和成功驯养的基础。2018年6月15日—8月15日,用焦点取样法对四川马尔康林麝繁育场的25头林麝进行了冲突行为取样及社会等级计算,采用放射免疫分析法检测了同期粪样的类固醇激素水平,分析了林麝社会等级与粪样皮质醇、睾酮及雌二醇水平的关系。结果表明:低等级雌麝的雌二醇水平(289.037±59.710 pg·g^-1,n=11)显著高于高等级雌麝(45.670±27.283pg·g^-1,n=6)(P<0.05),低等级雄麝的睾酮水平(3.863±1.538 ng·g^-1,n=3)和高等级雄麝(8.017±1.295 ng·g^-1,n=5)无显著差异(P>0.05);低等级雄麝(37.891±7.564 ng·g^-1,n=3)和雌麝(37.262±1.544 ng·g^-1,n=11)的皮质醇水平与高等级雄麝(29.947±2.441 ng·g^-1,n=5)及雌麝(37.478±4.628 ng·g^-1,n=6)间的差异不显著(P>0.05)。不区分性别,低等级林麝的皮质醇水平(37.397±1.826 ng·g^-1,n=14)和高等级个体(34.055±2.886ng·g^-1,n=11)间无显著差异(P>0.05)。研究结果表明,圈养林麝雌体的社会等级与其粪样雌二醇水平呈负相关,低等级雌麝的粪样雌二醇水平显著高于高等级雌麝。在麝类驯养实践中,可监测雌麝的社会等级和粪样雌二醇水平变化,预测雌麝的行为健康及繁殖成效。     

Reproductive patterns in mantled howler monkeys: Estrus,mate choice and copulation

The present study was undertaken to evaluate non-random mating patterns in two groups of mantled howler monkeys in two tropical dry forest habitats. Sexual dimorphism, female estrus stage, male dominance rank, sexual solicitations and copulations were assessed. Males are significantly larger than females, but female weight varies more than male weight. The length of female estrus cycles is comparable in both habitats, but females in the more strongly seasonal habitat demonstrate greater estrus synchrony relative to their numbers. Males solicit potential mates more frequently than females, a pattern explained by the relatively high rate of sexual solicitation by high-ranking males. Females in “peak” estrus solicit “alpha” males, while females in other stages of estrus solicit males equally by rank. Intersexual aggression occurs rarely, and “forced copulations” are attempted but, apparently, are unsuccessful. Sexual solicitations by “alpha” males and “peak” estrus females are most likely to lead to copulation, and “alpha” males are more likely to copulate than “gamma” males. In general, latencies from first solicitation to copulation are expensive in time, especially for high-ranking males. Estimated annual reproduction success favors high-ranking males, and results indicate that male and female mating behavior is mutually coordinated and controlled.     

Sexual behavior and hormone levels during the menstrual cycles of rhesus monkeys.

The sexual interactions of 10 pairs of rhesus monkeys were observed during a control and an experimental menstrual cycle of each female. During the experimental cycle the females were treated with an antiandrogen, flutamide. Daily peripheral serum levels of estradiol, testosterone, and progesterone in each female were determined by radioimmunoassay. Sexual behavior did not correlate reliably with female serum concentrations of any hormone measured nor with the menstrual cycle stage. Administration of the antiandrogen to the females did not affect the sexual behavior of the pairs, although female serum levels of estradiol and testosterone were reduced. It was concluded that although female ovarian hormones may influence rhesus sexual interactions under some circumstances, the normal hormonal fluctuations during the menstrual cycle need not regulate this behavior; a knowledge of an intact rhesus female's hormonal condition does not allow accurate predictions about behavior displayed during laboratory pair tests with a male.     

Effects of suppressing gonadal hormones on response to novel objects in adolescent rats

Human adolescents exhibit higher levels of novelty-seeking behaviour than younger or older individuals, and novelty-seeking is higher in males than females from adolescence onwards. Gonadal hormones, such as testosterone and estradiol, have been suggested to underlie age and sex difference in response to novelty; however, empirical evidence in support of this hypothesis is limited. Here, we investigated whether suppressing gonadal hormone levels during adolescence affects response to novelty in laboratory rats. Previously, we have shown that male adolescent Lister-hooded rats (postnatal day, pnd, 40) exhibit a stronger preference than same-aged females for a novel object compared to a familiar object. In the current study, 24 male and 24 female Lister-hooded rats were administered with Antide (a gonadotrophin-releasing hormone antagonist), or with a control vehicle solution, at pnd 28. Antide provided long-term suppression of gonadal hormone production, as confirmed by ELISA assays and measurement of internal organs. Response to novel objects was tested at pnd 40 in Antide-treated and control subjects using a ‘novel object recognition’ task with a short (2-minute) inter-trial interval. In support of previous findings, control males exhibited a stronger preference than control females for novelty when presented with a choice of objects. Antide-treated males exhibited a significantly lower preference for novel objects compared to control males, whilst Antide-treated females did not differ significantly from control females in their preference for novelty. Antide treatment did not affect total time spent interacting with objects. We discuss how gonadal hormones might influence sex differences in preference for novelty during adolescence.     

Effects of suppressing gonadal hormones on response to novel objects in adolescent rats

Human adolescents exhibit higher levels of novelty-seeking behaviour than younger or older individuals, and novelty-seeking is higher in males than females from adolescence onwards. Gonadal hormones, such as testosterone and estradiol, have been suggested to underlie age and sex difference in response to novelty; however, empirical evidence in support of this hypothesis is limited. Here, we investigated whether suppressing gonadal hormone levels during adolescence affects response to novelty in laboratory rats. Previously, we have shown that male adolescent Lister-hooded rats (postnatal day, pnd, 40) exhibit a stronger preference than same-aged females for a novel object compared to a familiar object. In the current study, 24 male and 24 female Lister-hooded rats were administered with Antide (a gonadotrophin-releasing hormone antagonist), or with a control vehicle solution, at pnd 28. Antide provided long-term suppression of gonadal hormone production, as confirmed by ELISA assays and measurement of internal organs. Response to novel objects was tested at pnd 40 in Antide-treated and control subjects using a ‘novel object recognition’ task with a short (2-minute) inter-trial interval. In support of previous findings, control males exhibited a stronger preference than control females for novelty when presented with a choice of objects. Antide-treated males exhibited a significantly lower preference for novel objects compared to control males, whilst Antide-treated females did not differ significantly from control females in their preference for novelty. Antide treatment did not affect total time spent interacting with objects. We discuss how gonadal hormones might influence sex differences in preference for novelty during adolescence.     

Natural or hormone-induced sexual and social behaviors in the female brown lemming (Lemmus trimucronatus)

The behaviors of intact or ovariectomized, estradiol benzoate-treated or estradiol benzoate followed by progesterone-treated female brown lemmings were compared. Intact, diestrous females engaged in more social interactions with a male than did ovariectomized females (Experiment 1). In the first 5 min of a 1-hr mating exposure (Experiment 2, Test A) intact females in natural estrus engaged in more social and sexual behaviors than did ovariectomized females in estrogen-induced estrus. However, during the last 5 min of the 1-hr exposure (Test B) ovariectomized females receiving estrogen alone continued to show high levels of sexual activity with a male partner, while intact estrous females or females receiving estrogen followed by progesterone showed an apparent drop in sexual receptivity and an increase in aggressivity. Aggressive behaviors, as indexed by threat-leap behaviors on the part of the female may increase in the presence of progesterone. Declines in sexual activity, occurring within 1 hr of progesterone injection, were apparently dependent on the interaction of progesterone and copulatory events which may affect both the male and female.     

The regulation of precopulatory behavior by ovarian hormones in the female Mongolian gerbil

The hormonal regulation of precopulatory behavior in the female Mongolian gerbil was studied using two groups (N = 6) of sexually experienced females. A novel testing procedure was used which involved females living continuously with test males for several days. The test males showed either full sexual behavior (copulating males, C) or only precopulatory behavior (noncopulating males, NC). Experiment 1 investigated changes during the estrous cycle and following ovariectomy in females. Experiment 2 studied the effects of hormonal treatment of these ovariectomized females with 6 micrograms estradiol benzoate (EB) followed by 0.4 mg progesterone (P) or by 0.04 ml arachis oil. When tested with NC males, females displayed a greater range of precopulatory behavior. The patterns could be classified into three groups according to the manner of response to ovariectomy and hormone treatment. Group I patterns (approach, leave, and olfactory investigation of the male's head) were affected by neither ovariectomy nor EB treatment relative to Day 3 levels (Day 3, day preceding estrus; Day 4, estrus), but they were increased to estrous levels by EB and P. Group II patterns (darting, foot-stomping, and the present and piloerection postures) appeared only during estrus, did not appear after ovariectomy, and reappeared only after sequential EB and P treatment. Group III patterns (investigation of the male's anogenital area, allogrooming, ventral gland marking, and sand-rolling) were reduced relative to both estrus and Day 3 levels by ovariectomy and increased above Day 3 levels by EB alone; EB and P treatment further increased Group III patterns to the level of estrus. It is suggested that female precopulatory behavior patterns differ in their responsiveness to ovarian hormones. Estrogen appears to affect those patterns associated with the earliest stages of estrus (Group III).