| Autor: |
Gardner M. Riley, T. C. Byerly |
| Rok vydání: |
1943 |
| Předmět: |
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| Zdroj: |
Poultry Science. 22:301-306 |
| ISSN: |
0032-5791 |
| DOI: |
10.3382/ps.0220301 |
| Popis: |
POULTRYMEN have long recognized that egg production can be increased during the fall and winter months by artificially lengthening the daily light period. Whetham (1933) correlated the seasonal rates of egg production of hens kept in latitudes throughout the world with the seasonal variations in length of daylight for these same latitudes. It was concluded that the light supply is an important factor in the seasonal distribution of egg production. It is only within recent years that the factors responsible for the striking physiological effect of increased light have been subjected to experimental investigation. It has been quite convincingly established that light stimulates the anterior pituitary gland which in turn releases the hormones necessary for gonadal development and functions. The extensive literature pertaining to this subject has been reviewed by Rowan (1938) and Bissonnette (1936). Penquite and Thompson (1933) reported the use of continuous lights on Leghorns and emphasized the . . . |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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