Archer G S, Shivaprasad H L, Mench J A
Department of Animal Science, University of California, Davis 95616, USA.
Poult Sci. 2009 Jan;88(1):29-37. doi: 10.3382/ps.2008-00221.
Environmental stimuli present during incubation can affect the behavior and health of birds posthatch. Commercial broiler chickens are often incubated in complete darkness, receiving light only intermittently when the incubator is opened. To determine the effect of providing light during the prehatch period, we incubated Cobb broiler eggs (n = 664) under continuous light (24L:0D), no light (0L:24D), or 12 h of light (12L:12D); the light level was 550 lx. Various parameters were measured posthatch in these broilers (n = 506), which were raised in floor pens on a 12L:12D regimen. There were no incubation treatment differences in hatchability, mortality, growth, feed consumption, feed conversion ratio, gait score, overall feeding behavior activity, or general behavioral activity. However, broilers hatched from eggs incubated under 24L:0D or 12L:12D had greater feeding activity (P < 0.05) than the 0L:24D broilers during the 2 h after the lights came on. Eye dimensions did not differ between treatments, but the eyes of the 12L:12D broilers weighed less (P < 0.05) than those of the other treatments. Broilers incubated under 0L:24D had a greater level of composite physical asymmetry (1.87 +/- 0.11 mm), considered to be an indicator of developmental stress, than did 12L:12D (1.57 +/- 0.09 mm; P = 0.05) broilers; they also tended to have more composite asymmetry than 24L:0D (1.62 +/- 0.11 mm; P = 0.10) broilers. The results of this study indicate that providing light during incubation has no detrimental effect on production or health of broilers, but does have potential benefits in terms of reducing the effects of stressors associated with production and growth.
孵化期间存在的环境刺激会影响雏鸡出壳后的行为和健康。商业肉鸡通常在完全黑暗的环境中孵化，仅在孵化器打开时才会间歇性地接受光照。为了确定孵化前提供光照的影响，我们将科宝肉鸡种蛋（n = 664）分别置于持续光照（24小时光照：0小时黑暗，24L:0D）、无光照（0小时光照：24小时黑暗，0L:24D）或12小时光照（12L:12D）条件下进行孵化；光照强度为550勒克斯。对这些在地面围栏中按照12L:12D光照制度饲养的肉鸡（n = 506）出壳后的各项参数进行了测量。在孵化率、死亡率、生长、采食量、饲料转化率、步态评分、总体采食行为活动或一般行为活动方面，孵化处理之间没有差异。然而，在光照开启后的2小时内，由24L:0D或12L:12D条件下孵化的种蛋孵出的肉鸡比0L:24D条件下孵出的肉鸡具有更高的采食活动（P < 0.05）。各处理间眼睛尺寸无差异，但12L:12D条件下孵出的肉鸡眼睛重量比其他处理的肉鸡轻（P < 0.05）。与12L:12D（1.57 ± 0.09毫米；P = 0.05）条件下孵出的肉鸡相比，0L:24D条件下孵出的肉鸡具有更高水平的综合身体不对称性（1.87 ± 0.11毫米），综合身体不对称性被认为是发育应激的一个指标；与24L:0D（1.62 ± 0.11毫米；P = 0.10）条件下孵出的肉鸡相比，0L:24D条件下孵出的肉鸡也往往具有更多的综合不对称性倾向。本研究结果表明，孵化期间提供光照对肉鸡的生产或健康没有不利影响，但在减轻与生产和生长相关的应激源影响方面确实具有潜在益处。
