Foerg R
Folia Primatol (Basel). 1982;38(1-2):108-21. doi: 10.1159/000156047.
Testicle size during the breeding season is related to age and previous social environment of the male. The size of testicles in adult males exceeds that of young males. Adult males' testicles are much larger than the testicles of young males; enlargement starts 2-3 months prior to the breeding season, peaking around copulation day. Subadult males (3-year-olds) are able to develop full-sized testicles and sire offspring, but did so only when housed with adult females and not with their family group. Although females may reach sexual maturity in their second breeding season after birth, they do not necessarily breed successfully. Vaginal estrus lasts considerably longer (2-3 days) than behavioral estrus (6-12 h). Different stages of vaginal estrus can visually be determined by the development of the vaginal region (swelling; appearance of pink point; long, pink slash; opening to round pink circle, and in the latter stage, by smears, confirming the different physiological stages, proestrus, estrus, metestrus). Behavioral estrus appears in the last hours of vaginal estrus. Captive adult females show increasingly hostile behavior to their maturing daughters. These have to be removed from the group when they are sexually mature. The same degree of hostility can be found between fathers and subadult sons during the breeding season. Dominant males show a typical 'guarding behavior' over the entire period of behavioral estrus of the female. They remain close to the female, vigorously preventing other males from approaching or mating with the female. At the beginning and the end of copulations, the female shows a sequence of aggressive behaviors towards the dominant male. Successful copulations can be determined by their duration (1-2 min), and a head-twisting movement of the male during ejaculation. Normally 16-25 copulations occur on copulation day, usually all with the same partners. The average gestation length is 102.5 days. Adult females normally give multiple births, whereas primiparous females tend to have single infants.
繁殖季节睾丸大小与雄性的年龄和先前的社会环境有关。成年雄性的睾丸大小超过年轻雄性。成年雄性的睾丸比年轻雄性的大得多；增大在繁殖季节前2至3个月开始，在交配日前后达到峰值。亚成年雄性（3岁）能够发育出全尺寸的睾丸并繁殖后代，但只有在与成年雌性而非其家族群体饲养在一起时才会这样做。虽然雌性可能在出生后的第二个繁殖季节达到性成熟，但它们不一定能成功繁殖。阴道发情期持续的时间（2至3天）比行为发情期（6至12小时）长得多。阴道发情期的不同阶段可以通过阴道区域的发育在视觉上确定（肿胀；出现粉红色点；长的粉红色斜线；开口变为圆形粉红色圆圈，在后期，通过涂片，确认不同的生理阶段，发情前期、发情期、发情后期）。行为发情出现在阴道发情期的最后几个小时。圈养的成年雌性对其成熟的女儿表现出越来越大的敌意。当女儿性成熟时，必须将她们从群体中移出。在繁殖季节，父亲和亚成年儿子之间也存在同样程度的敌意。占主导地位的雄性在雌性行为发情的整个期间表现出典型的“守护行为”。它们与雌性保持近距离，大力阻止其他雄性接近或与雌性交配。在交配开始和结束时，雌性对占主导地位的雄性表现出一系列攻击行为。成功的交配可以通过其持续时间（1至2分钟）以及雄性射精时的头部扭转动作来确定。通常在交配日会发生16至25次交配，通常都是与相同的伴侣。平均妊娠期为102.5天。成年雌性通常会多胎分娩，而初产雌性往往只生单胎。
