ISSN:
0362-2525
Schlagwort(e):
Life and Medical Sciences
;
Cell & Developmental Biology
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Biologie
,
Medizin
Notizen:
Between December 10th and January 24th, using red, green, and white electric lights at equal intensities of about 1.7 foot-candles, sixty-nine males, with females, were subjected nightly to, (a) constant six- and six-and-one-quarter-hour periods of illumination; (b) periods increasing gradually from one-quarter to six and one-quarter hours; (c) no added light (controls), in a basement room lighted by day from three large windows. Relative heat intensities reaching the birds were: for white, 1; for green, 2.5; for red, 10.Birds were killed for testis study at 5, 12, 16, 22, and 23 days.Refractory period was shorter, and modification of spermatogenic activity much greater, under a than under b types of treatment, as compared with controls. Effects were also more consistent.Descending order of testis activity induced at all stages was red, white, control, green, under both a and b.Effects on testis activity are not proportional to heat intensity of incident light, but depend on wave length, since green effect is not intermediate between those of white and red, as its heat intensity is. Green inhibited germ-cell activity even in birds already at normal midwinter minimal condition.Constant six-hour red-light treatments, of this intensity, induced flrst appearance of metamorphosing sperms in twenty-three days in midwinter.Apparatus and mode of light regulation and measurement are described.
Zusätzliches Material:
1 Tab.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/jmor.1050520204
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