[Adaptations in reproduction and behavior of captive chimpanzees-- zoobiological and veterinary managements]

Monitoring of renal LH-excretion, changes in genital tumescence and menses assesses reproductive status in zookept female chimpanzees. Temporary detumescence of female sex skin in estrus is a reliable indicator for stress. Assessment of female chimpanzee reproductive status relates to local and individual variation of cycle length and temporal correlation of investigated parameters. Monitoring of neonate chimpanzee behavioural ontogeny is an essential tool of evaluating applied rearing methods since individuals were to be integrated into the adult group during adolescence. Slow and continuous transition periods between consecutive rearing phases avoid irreversible disturbed behaviour. Care by one person up to the age of 12 months, followed by a 3 year stay in a peer group guarantee normal development in zookept infant chimpanzees. 4-5 years old chimpanzees with infantile attributes and abilities to submit and appease can be integrated to adults with low risk. In female gorillas sexual cyclicity was monitored by renal excretion of LH, length of menses, sexual behaviour and--in tame females--by basal body temperature and variation of length of the urogenital cleft. Intraspecific variation of cyclicity allowed individual fertility assessment after comparison of several cycles. Analyses of behaviour gave hints to overcharged adaptability and reduced infertility under inadequate maintenance. Data on semen and testicular biopsy improve fertility evaluation in gorilla males and point to degree and time of tissue alteration and etiology. Body hygiene analogous to the human, tool use and interspecific play with chimpanzees and humans behind window screens were observed in inadequately kept gorillas. Homosexual behaviour among females was reversible with environmental and social changes. Coalitions among nonrelated females were an effective social strategy against an aggressive male. Cyclicity was disturbed drastically by social events such as physical lesions made by a male but normalized with improved social situation. Disturbed cyclicity featured prolongation of interestrus intervals and complete detumescence, oligomenorrhea and amenorrhea. Nulliparous females in their third decennium needed more than 1.5 years of social contact to a fertile male to become fullterm pregnant. During the first two months of pregnancy stillbirths and embryonic resorptions were detected. Handreared and inexperienced primiparous gorilla females accepted their infants and reared them normally after witnessing motherrearing in neighbored chimpanzee females for several years. Opportunities of free choice and decision making determine zookept pongid behaviour, that cannot be compared with prisoners' ethology. Adaptations of ontogenetic behaviour and reproduction, teleonomic patterns and zoomorphism are of zoobiological relevance. Adaptations develope during prolonged periods of time and thus results of corresponding management issues are to be assessed a posteriori.