Research note: influence of ahemeral light:dark cycles on egg traits in brown egg pullets.
Brown egg pullets (DeKalb Sex-Sal) were subjected to an ahemeral lighting program to determine their response in terms of egg traits. All birds were reared on a conventional lighting program of 10 h light (L):14 h dark (D) to 16 wk. At 16 wk, all birds received a schedule of 11L:13D followed by a weekly 1-h increase in photoperiod to 14L:10D at 19 wk. Control treatment (CON) birds were continued on this schedule. Ahemeral treatment (AHM) birds were given a 28-h schedule 14L:14D at 23 wk that was continued to 28 wk, then returned to a 24-h cycle of 14L:10D. Shell weight responded quickly to the ahemeral treatment and showed a significant (P less than .05) increase during the 2nd 28-h cycle. Shell thickness and total egg weight showed significant increases on the 3rd cycle; albumen weight showed an increase on Cycle 4, and yolk weight increased significantly only on the 8th cycle. When AHM treatment birds were returned to a conventional cycle (14L:10D) at 28 wk, the total weight remained significantly higher (P less than .05) as late as Cycle 6.
Lakshmanan
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Department of Animal, Veterinary, and Aquatic Sciences, University of Maine, Orono 04469.
Hawes
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Kling
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D000818:Animals; D002645:Chickens / Q000502:physiology*; D004528:Egg Shell / Q000033:anatomy & histology; D004529:Egg White; D004530:Egg Yolk; D004531:Eggs / Q000592:standards*; D005260:Female; D008027:Light; D010507:Periodicity