Genotypic differences in speed and magnitude of response to ahemeral lighting.
1. The paper compares between three genetically different lines in their egg weight and shell thickness response to a 28-h cycle. 2. The response in shell thickness to ahemeral lighting was more rapid (2.2 d) than for egg weight (4.2 d). 3. Differences between genotypes were evident in both the speed and magnitude of response. 4. Overall, egg weight and shell thickness on the 28-h cycle were 7% and 8% greater than on 24 h. 5. The allometric increase indicates that the increase in shell weight was on average 14% more than the increase in egg weight.
Shanawany
M M
MM
National Institute of Animal Science, Foulum, Denmark.
Sørensen
P
P
Pirchner
F
F
D000818:Animals; D002645:Chickens / Q000235:genetics* / Q000502:physiology; D004528:Egg Shell; D004531:Eggs; D005260:Female; D005838:Genotype; D017440:Photoperiod