Related Experiment Video
Updated: Aug 12, 2026

Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid
Published on: August 8, 2017
Influence of light sources on the growth and reproduction of large white turkeys
J V Felts1, A T Leighton, D M Denbow
1Department of Poultry Science, Virginia Polytechnic Institute and State University, Blacksburg 24061-0332.
Abstract:
The present study evaluated the effects of sodium vapor (SV), daylight fluorescent (FL) and incandescent (IN) light sources on the growth and reproduction of primary turkeys. Large White turkeys (90 sire line and 324 dam line) were reared by sex under one of the three light sources from 8 to 22 wk of age. At 22 wk of age, all males and females were preconditioned under their assigned light source, but the photophase was restricted to 6 h per day at an intensity of 21.6 lx. At 33 wk of age, the males were exposed to 16 h of light per day under the same light sources in which they were reared. At 35 wk of age, the females were reassigned to the various light sources in order to achieve all possible combinations of adolescent and breeder light-source treatments. Sixteen hours of light per day were provided at an intensity of 53.8 lx during a 20-wk cycle of egg production. The body weights of males and the feed efficiencies of males and females were unaffected by the adolescent light-source treatment. The females were significantly heavier under SV than those under FL and IN lights. Hen-housed egg production was significantly higher for females exposed to SV and FL lights versus IN during the first 10-wk production period. Hen-day egg production was significantly higher for females given FL than for those provided SV and IN lights. However, total hen-housed and hen-day production was unaffected by either adolescent or breeder light-source treatments. Fertility, hatchability, days to first egg, egg weight, and egg specific gravity were also unaffected by either the adolescent or breeder light-source treatment. (ABSTRACT TRUNCATED AT 250 WORDS)
Related Concept Videos
Photoreceptors and Plant Responses to Light
Testing a Claim about Mean: Known Population SD
Estimating a population mean requires the samples to be distributed normally. The data should be collected from the randomly selected samples having no sampling bias. The sample size needed to be higher than 30, and most importantly, the population standard deviation should be already known.
In most realistic situations, the population standard deviation is often unknown, but in rare circumstances, when it...

