نتایج جستجو برای: copulation before maturity or after it

تعداد نتایج: 6137809  

Journal: :Neuron 2016
Hui-Hao Lin De-Shou Cao Sachin Sethi Zheng Zeng Jacqueline S.R. Chin Tuhin Subhra Chakraborty Andrew K. Shepherd Christine A. Nguyen Joanne Y. Yew Chih-Ying Su Jing W. Wang

During the lifespans of most animals, reproductive maturity and mating activity are highly coordinated. In Drosophila melanogaster, for instance, male fertility increases with age, and older males are known to have a copulation advantage over young ones. The molecular and neural basis of this age-related disparity in mating behavior is unknown. Here, we show that the Or47b odorant receptor is r...

Journal: :Folia parasitologica 2004
George S Slyusarev

The genital pore of the female of Intoshia variabili Aleksandrov et Sljusarev, 1992 is located on a transverse ring of non-ciliated cells. Before copulation it is occupied by 6-7 cells that develop in the epithelium and that for a time are beneath the surface. When fully developed, these cells contain many electron-dense granules and their apical surface is covered with numerous microvilli. Aft...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2009
William G Eberhard

In one of his few major oversights, Darwin failed to appreciate that male-male competition and sexual selection can continue even after copulation has begun. The postcopulatory equivalents of both direct male-male battles (sperm competition) and female choice (cryptic female choice) occur within the female's body. Recognition of this hidden, but intense, sexual competition provides new insights...

Journal: :The Journal of neuroscience : the official journal of the Society for Neuroscience 1997
D S Lorrain L Matuszewich R D Friedman E M Hull

Serotonin (5-HT) is generally inhibitory to masculine sexual behavior. It has been suggested that 5-HT released after ejaculation may promote the sexual quiescence of the postejaculatory interval (PEI). The following experiments were conducted to test (1) whether extracellular 5-HT increases in either the anterior lateral hypothalamic area (LHAA) or the medial preoptic area (MPOA) of male rats ...

اکبری, محمد , حسین نوری, سید محمد , حیدری, زهرا , مینایی زنگی, باقر ,

Amount of environmental lead pollution is increased with progression of industry. This pollution is able to damage the living beings in many ways. Blood and Immune systems are more sensitive to toxic effects of lead. 30 female and 6 male rats from Sprague dawley race are chosen by simple random sampling. After copulation and vaginal plug observation, expectant rats are calssified in test and co...

Journal: :Endocrinologia japonica 1977
S Ishida T Nihei M Kawakami

Adult female New Zealand white rabbits with chronically implanted electrodes were used. Potentials (EVPs) were consistently evoked in the medial basal hypothalamus (MBH) including the median eminence and the arcuate nucleus by stimulation of the dorsal. hippocampus (HPC), medial amygdala (AMYG) and preoptic area (POA). These EVPs were variously influenced under endogenous or exogenous hormonal ...

Journal: :The Journal of neuroscience : the official journal of the Society for Neuroscience 2001
J Dominguez J V Riolo Z Xu E M Hull

The medial preoptic area (MPOA) is a critical integrative site for male copulatory behavior in most vertebrate species. Extracellular dopamine (DA) is increased in the MPOA of male rats immediately before and during copulation. DA agonists microinjected into the MPOA of male rats facilitate and DA antagonists inhibit sexual behavior. A major source of input to the MPOA is the medial amygdala (M...

Journal: :Brain research bulletin 1997
E M Hull J Du D S Lorrain L Matuszewich

Steroid hormones prime neural circuits for sexual behavior, in part by regulating enzymes, receptors, or other proteins affecting neurotransmitter function. Dopamine facilitates male sexual behavior in numerous species and is released before and/or during copulation in three integrative neural systems. The nigrostriatal system enhances readiness to respond; the mesolimbic system promotes many a...

Journal: :American journal of primatology 2002
Stuart Semple Karen McComb Susan Alberts Jeanne Altmann

In a wide variety of animal species, females produce vocalizations just before, during, or immediately after copulation. Observational and experimental evidence indicates that these copulation calls are sexually selected traits, functioning to promote competition between males for access to the calling female. In this paper, we present an acoustic analysis of variation in the form of copulation...

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