The purpose of this study was to investigate the effects of light on farrowing performance in sows. Thirty sows were moved to the farrowing unit at d 110 of gestation and were assigned one of two treatments: 12 h light/dark cycle (Dark) or 24 h light (Light). Treatments were initiated upon entry into the farrowing unit until completion of farrowing was confirmed. For Dark sows, the farrowing crates were structured with light blocking tarps that were lowered at 1900 hr and raised at 0700 hr daily. Video recording devices were installed above all sows and continuous video was recorded from initiation of the treatments until farrowing was complete. Data collected included duration of farrowing, birthing interval, number of stillborn piglets as an indirect measure of dystocia, total born, and liveborn piglets. All statistical analyses were performed using the mixed procedure of SAS, where the experimental unit was individual sow. Funding for this project was provided by the National Pork Checkoff and the U.S. Pork Center of Excellence. Dark sows were more likely to give birth closer to their due date compared to Light sows (1.34 vs. 2.16 ± 0.24 days relative to a 115-day due date, respectively; P = 0.02). Total duration of parturition did not differ between treatments (P = 0.56). Number of liveborn piglets between treatments did not differ (P = 0.68), however the number of stillborn piglets between treatments was different (P = 0.02), where Dark sows had a higher incidence of stillborn piglets compared to Light sows (1.52 vs. 0.65 ± 0.25 stillborn piglets/litter, respectively). The interval between piglets did not differ between treatments (P = 0.93). It is hypothesized that the effects on due date and increased incidence of stillborn piglets was caused by increased stress due to visual isolation in the Dark sows.

中文翻译：

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PSVI-1 光照团对母猪分娩性能的影响

本研究的目的是调查光照对母猪分娩性能的影响。30 头母猪在妊娠第 110 天被转移到分娩单元，并被分配两种处理中的一种：12 小时光照/黑暗周期（黑暗）或 24 小时光照（光照）。进入产房后开始处理，直到确认产仔完成。对于深色母猪，产仔栏采用遮光防水布构成，每天 1900 时放下，每天 0700 时抬起。在所有母猪上方都安装了视频记录设备，并从治疗开始到分娩完成连续记录视频。收集的数据包括分娩持续时间、分娩间隔、作为难产、总出生和活产仔猪的间接衡量标准的死产仔猪数量。所有统计分析均使用SAS的混合程序进行，其中实验单位为单头母猪。该项目的资金由 National Pork Checkoff 和美国猪肉卓越中心提供。与浅色母猪相比，深色母猪更有可能在更接近其预产期的日期分娩（相对于 115 天的预产期，分别为 1.34 与 2.16 ± 0.24 天；P = 0.02）。分娩的总持续时间在治疗之间没有差异（P = 0.56）。处理之间的活产仔猪数量没有差异（P = 0.68），但是处理之间的死产仔猪数量不同（P = 0.02），与浅色母猪相比，深色母猪的死产仔猪发生率更高（1.52 vs. 0.65） ± 0.25 死产仔猪/窝，分别）。仔猪之间的间隔在处理之间没有差异（P = 0.93）。