Biomaterial Database

Effects of ewe proximity on peripheral plasma testosterone levels and behaviour in the ram. 1976

A W Illius, and N B Haynes, and G E Lamming

Groups of yearling and immature rams were kept for 6 months during the breeding season either adjacent to or apart from ovariectomized ewes in which oestrus was induced by hormone therapy. The older rams kept near ewes were found to have larger testes, higher plasma testosterone levels and greater sexual and aggressive activity, although the immature animals showed no response. Plasma testosterone concentration was also found to increase after copulation in some animals.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009929	Organ Size	The measurement of an organ in volume, mass, or heaviness.	Organ Volume,Organ Weight,Size, Organ,Weight, Organ
D003307	Copulation	Sexual union of a male and a female in non-human species.	Copulations
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000367	Age Factors	Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.	Age Reporting,Age Factor,Factor, Age,Factors, Age
D000374	Aggression	Behavior which may be manifested by destructive and attacking action which is verbal or physical, by covert attitudes of hostility or by obstructionism.	Aggressions
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012726	Sexual Behavior, Animal	Sexual activities of animals.	Mating Behavior, Animal,Sex Behavior, Animal,Animal Mating Behavior,Animal Mating Behaviors,Animal Sex Behavior,Animal Sex Behaviors,Animal Sexual Behavior,Animal Sexual Behaviors,Mating Behaviors, Animal,Sex Behaviors, Animal,Sexual Behaviors, Animal
D012756	Sheep	Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.	Ovis,Sheep, Dall,Dall Sheep,Ovis dalli
D012934	Social Isolation	The separation of individuals or groups resulting in the lack of or minimizing of social contact and/or communication. This separation may be accomplished by physical separation, by social barriers and by psychological mechanisms. In the latter, there may be interaction but no real communication.	Isolation, Social,Social Exclusion,Exclusion, Social,Social Exclusions