Koelkebeck K W, Biellier H V
Poult Sci. 1986 Nov;65(11):2002-7. doi: 10.3382/ps.0652002.
To compare the effects of using continuous (C) vs. intermittent (I) photoperiods with normal (24 hr) and a long but decreasing light-dark cycle (LDLDC) on production performance and egg quality, 240 White Leghorn hens of the University of Missouri-Columbia strain were individually caged in light-controlled rooms. Treatments applied at 21 weeks of age were light-dark cycles (LDC) of 25 hr gradually reduced to 23.5 hr with C or I photoperiods, and 24-hr LDC (controls); C or I photoperiods were gradually increased from 13.75 to 16 hr for the 25- to 23.5-hr LDC, and from 13.75 to 15 hr for the 24-hr LDC. Data were obtained on hen-day egg production, egg weight, egg mass, egg specific gravity, Haugh units, feed consumption, and feed efficiency. Hen-day egg production was significantly greater (P less than .01) for the combined C photoperiod treatments, while hens consumed significantly less (P less than .05) feed exposed to the combined I photoperiod treatments. Egg specific gravity was significantly better (P less than .05) for the LDLDC vs. the 24-hr LDC program with the difference being attributed to an increase (P less than .05) in initial egg specific gravity with the use of a 24-hr LDC. Egg weight, egg mass, Haugh units, and feed efficiency were not affected (P greater than .05) by LDC or photoperiod treatments.
为比较连续（C）光照周期与间歇（I）光照周期，以及正常（24小时）光照-黑暗周期和长但递减的光照-黑暗周期（LDLDC）对生产性能和蛋品质的影响，将240只密苏里大学哥伦比亚分校品系的白来航母鸡单独饲养在光照控制的房间内。21周龄时采用的处理方式为：25小时光照-黑暗周期（LDC），逐渐减至23.5小时，采用C或I光照周期；24小时LDC（对照组）；对于25至23.5小时LDC，C或I光照周期从13.75小时逐渐增加至16小时，对于24小时LDC，从13.75小时逐渐增加至15小时。获取了母鸡日产蛋量、蛋重、蛋重、蛋比重、哈夫单位、采食量和饲料效率的数据。C光照周期组合处理的母鸡日产蛋量显著更高（P<0.01），而接受I光照周期组合处理的母鸡采食量显著更低（P<0.05）。与24小时LDC方案相比，LDLDC的蛋比重显著更好（P<0.05），差异归因于使用24小时LDC时初始蛋比重增加（P<0.05）。光照-黑暗周期（LDC）或光照周期处理对蛋重、蛋重、哈夫单位和饲料效率没有影响（P>0.05）。
