Neural activation following offensive aggression in Japanese quail

Cornelia Voigt; Katharina Hirschenhauser; Stefan Leitner

doi:10.1242/bio.038026

A photoperiodic response in gonadectomized Japanese quail exposed to a single long day

Journal of Endocrinology ◽

10.1677/joe.0.0970121 ◽

1983 ◽

Vol 97 (1) ◽

pp. 121-126 ◽

Cited By ~ 53

Author(s):

T. J. Nicholls ◽

B. K. Follett ◽

J. E. Robinson

Keyword(s):

Japanese Quail ◽

Endocrine System ◽

Experimental System ◽

Photoperiodic Response ◽

Neural Activation ◽

Continuous Darkness ◽

Long Day ◽

Gonadotrophin Secretion ◽

Enhanced Secretion ◽

Long Photoperiod

Gonadectomized male Japanese quail maintained on short daylengths (8 h light: 16 h darkness) showed a reliable and repeatable response, in terms of increased gonadotrophin secretion, to a single long photoperiod (20 h light) followed by continuous darkness. Plasma levels of LH were significantly increased within 4 h of the end of the long day. Secretion continued to increase with time and LH and FSH concentrations reached a maximum some 24 h later, thereafter decreasing only slowly over the next 8–10 days. Quail could be used repeatedly at fortnightly intervals and gave a consistent response for at least 15 months. The size of the photoperiodic response and its considerable duration were much greater than found in intact quail. The birds showed a similar (though reduced) response if a short daylength was followed by a single 4-h light pulse interrupting the 16-h dark period. Using this system the time of maximum responsivity to the inductive effects of light lies 10–16 h from 'dawn'. The marked and rapid effects described provide an excellent experimental system in which to study how photoperiodic changes are recognized and how consequent neural activation is translated into enhanced secretion rates of hormones in the peripheral endocrine system.

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The Quantitative Ultrastructure of the Heart Muscle of Japanese Quail by Hypergravitation, Hypodynamy and Combination

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158480 ◽

1990 ◽

Vol 48 (3) ◽

pp. 188-189

Author(s):

Anton Bózner ◽

Mikuláš Gažo ◽

Jozef Dostál

Keyword(s):

Japanese Quail ◽

Heart Muscle ◽

Relative Size ◽

Combination Group ◽

Control Group ◽

Group V ◽

Group Iii ◽

Space Flights ◽

Group I ◽

Quantitative Ultrastructure

It is anticipated that Japanese quail /Coturnix coturnix japonica/ will provide animal proteins in long term space flights. Consequently this species of birds is of research interest of international space program INTERCOSMOS. In the year 1987 we reported on an experiment /2/ in which the effect of chronic acceleration of 2 G hypergravitation, the hypodynamy and the simultaneous effect of chronic acceleration and the location in the centre of the turntable of the centrifuge on the protein fractions in skeletal muscles was studied. The ultrastructure of the heart muscle was now in this experiments examined as well.Japanese quail cockerels, aged 48 days were exposed to 2 G hypergravitation /group IV/ in a 6,4 m diameter centrifuge, to hypodynamy /group III/ and their combination /group V/, respectively for 6 days / Fig.1/. The hypodynamy in group III was achieved by suspending the birds in jackets without contact the floor. The group II was located in the centre ofthe turntable of the centrifuge. The control group I. was kept under normal conditions. The quantitative ultrastructure of myocard was evaluated by the methods of Weibel/3/ - this enables to determine the number, relative size and volume of mitochondria volume of single mitochondria, defficiency of mitochondrial cristae and volume of myofibrils.

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