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Author Andrew, R.J.
Title Changes in visual responsiveness following intercollicular lesions and their effects on avoidance and attack Type Journal Article
Year 1974 Publication Brain, Behavior and Evolution Abbreviated Journal Brain Behav Evol
Volume 10 Issue (up) 4-5 Pages 400-424
Keywords Animals; Chickens; Humans; Male; Mutism; Superior Colliculi/*physiology; Tectum Mesencephali; Testosterone; Visual Fields; Vocalization, Animal
Abstract In the normal chick, conspicuous visual stimuli induce targetting and pecking together, with vocalization. All three are abolished by lesion of the intercollicular area (ICo) or of connections passing through its medial margin. After such lesions, chicks also cease to treat significant visual stimuli as if they were startling and exciting, and may delay response as a result. However, they are still able to recognise, orient accurately to, and respond appropriately to, a variety of complex visual stimuli (e.g. food grains, copulation object). In addition, they are little affected by strange surroundings. Lesion evidence suggests the mammalian subcollicular area to have similar functions to the ICo and to be homologous with it. A route (present in bird), which is well-known in mammals for its association with threat, defense and escape evoked by strange and frightening objects (amygdala-diencephalic periventricular system-central mesencephalic grey, A-DPS-CMG) is stimuli via the 2 ICo (subcollicular area). Two different mechanisms may be involved caudal to the ICo. One consists of tectal afferents which might modulate the evocation of targetting, pecking and other responses via the tectum. The other is the predorsal system of tectal efferents which may mediate such responses. Classical syndromes of tameness and unresponsiveness produced by various interruptions of the A-DPS-CMG route may depend on interruption of connections to these midbrain mechanisms. Attack is depressed by ICo lesions as one aspect of reduced responsiveness to conspicuous and startling visual stimuli. Avoidance, which is apparently mediated by a separate system, much as in Anura, is facilitated.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0006-8977 ISBN Medium
Area Expedition Conference
Notes PMID:1169102 Approved no
Call Number Equine Behaviour @ team @ Serial 4626
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Author Khalil, A.M.; Murakami, N.; Kaseda, Y.
Title Relationship between plasma testosterone concentrations and age, breeding season and harem size in Misaki feral horses Type Journal Article
Year 1998 Publication The Journal of veterinary medical science / the Japanese Society of Veterinary Science Abbreviated Journal J Vet Med Sci
Volume 60 Issue (up) 5 Pages 643-645
Keywords Age Factors; Animals; Animals, Wild; *Horses; Japan; Male; Reproduction; Seasons; Sexual Behavior, Animal; Sexual Maturation; *Social Behavior; Testosterone/*blood
Abstract Jugular vein blood samples were collected from 23 young and sexual mature feral stallions to examine the relationship between plasma testosterone concentration and age, breeding season or harem size. Testosterone concentration increased with the age of the stallions until they formed their own harems, at about 4 to 6 years old. Seasonal variations in testosterone concentrations were observed, and found to be significantly higher (P<0.001) throughout the breeding season than non-breeding season, from 3 years of age. Testosterone levels were correlated with harem size for individual stallions. It can be inferred from these results that there is a relationship between plasma testosterone concentration and age, breeding season and harem size.
Address Laboratory of Animal Behavioral Science, Faculty of Agriculture, Miyazaki University, Japan
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0916-7250 ISBN Medium
Area Expedition Conference
Notes PMID:9637303 Approved no
Call Number refbase @ user @ Serial 137
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Author Villani, M.; Cairoli, F.; Kindahl, H.; Galeati, G.; Faustini, M.; Carluccio, A.; Veronesi, M.C.
Title Effects of mating on plasma concentrations of testosterone, cortisol, oestrone sulphate and 15-ketodihydro-PGF2alpha in stallions Type Journal Article
Year 2006 Publication Reproduction in Domestic Animals = Zuchthygiene Abbreviated Journal Reprod Domest Anim
Volume 41 Issue (up) 6 Pages 544-548
Keywords Animals; Dinoprost/*analogs & derivatives/blood; Ejaculation/physiology; Estrone/*analogs & derivatives/blood; Horses/*blood/physiology; Hydrocortisone/*blood; Male; Sexual Behavior, Animal/*physiology; Testosterone/*blood
Abstract Very little information is available regarding the physiological mechanisms involved in the normal sexual activity in the stallion and, in particular, the endocrine control of reproduction is still not clearly understood. This experiment was designed to determine the short-term effect of sexual stimulation on plasma concentrations of testosterone, cortisol, oestrone sulphate and 15-ketodihydro-PGF(2alpha) in stallions. Semen samples were collected from 10 lighthorse stallions of proven fertility using a Missouri model artificial vagina. At the same time, blood samples were collected from the jugular vein with heparinized tubes, 20 and 10 min before oestrous mare exposure, at exposure and 10, 20, 30 min after dismounting. Testosterone concentrations showed a sharp rise 10 min after mating (p < 0.001), reached a plateau, and then showed a further increase 30 min after mating (p < 0.001). Cortisol concentrations increased 10 min after mating (p < 0.001) and remained at high levels in the subsequent samples taken. A peak of oestrone sulphate was observed 10 min after mating (p < 0.001). 15-Ketodihydro-PGF(2alpha) concentrations decreased rapidly at the moment of the exposure of the stallions to an oestrous mare (p < 0.05), returned to pre-mating concentrations and then decreased again 30 min after mating (p < 0.05).
Address Dipartimento di Scienze Cliniche Veterinarie, Sez. Clinica Ostetrica e Ginecologica Veterinaria, Milan, Italy
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0936-6768 ISBN Medium
Area Expedition Conference
Notes PMID:17107515 Approved no
Call Number Serial 1855
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