Department of Animal Biosciences, University of Guelph, Guelph, Ontario, Canada.
Department of Animal Science, Michigan State University, East Lansing, Michigan, USA.
Poult Sci. 2017 Jun 1;96(6):1515-1523. doi: 10.3382/ps/pew436.
Hens are motivated to seek out an enclosed nest site, but it is unclear whether the single communal nest in enriched colony cages (EC) adequately supports nesting. One method to investigate this is to provide an "alternative nest site" and determine the effects on laying location, timing of oviposition, and pre-laying behavior. The objective of this experiment was to determine whether increasing the degree of enclosure in the scratch area would influence egg laying location, time of oviposition, and pre-laying behavior. Hy-Line W-36 hens (n = 1,560) were reared in standard cages and housed in four rooms, each with six Chore-Time EC, at wk 17 (65 birds/cage at 729 cm2 floor space and 62 cm2 nest space per bird). At 21 wk, the scratch area of the enclosed (E; n = 12) treatment cages was fitted with a wire partition and red vinyl curtain; open (O; n = 12) cages were unmodified. The number of eggs laid in each location (nest, middle, scratch) was counted over 4 d. Nest and scratch areas were instantaneously scan sampled every 20min from 0630 h to 1330 h to count the number of sitting hens and the number of eggs. Aggressive pecks, threats, and displacements were counted in each area during a 30 s interval scan (3 scans/time period, 5 periods). Mixed model analyses tested the effect of treatment, time, room, position, and tier. There was no significant main effect of treatment on the percentage of eggs laid in the nest or scratch areas, but E treatment hens were more aggressive (P = 0.027). The numbers of hens sitting and eggs laid in the nest peaked between 0830 h to 0930 h (P < 0.0001), with a peak in displacements between 0800 h to 1000 h (P < 0.0001). Peak laying time occurred later in the scratch area (0930 h to 1030 h). Treatment affected few nesting behavior patterns, and the behavior differences between the nest and scratch areas replicated earlier findings. Hy-Line W-36 hens seemed to perceive the existing nest as satisfactory, with little evidence for competition.
母鸡有寻找封闭巢位的动机，但尚不清楚丰富化鸡笼（EC）中的单个公共巢是否能充分满足其筑巢需求。一种研究方法是提供“替代巢位”，并确定其对产蛋位置、产卵时间和产蛋前行为的影响。本试验的目的是确定增加沙坑区的封闭程度是否会影响产蛋位置、产卵时间和产蛋前行为。饲养于标准鸡笼中的海兰 W-36 母鸡（n = 1560）饲养于 4 个房间中，每个房间有 6 个 Chore-Time EC，在第 17 周（729 cm2 鸡笼底面积和每只鸡 62 cm2 产蛋窝面积下，每笼 65 只鸡）。在第 21 周，封闭（E；n = 12）处理鸡笼的沙坑区安装了金属丝隔板和红色乙烯基窗帘；开放（O；n = 12）鸡笼则没有任何改动。连续 4 天记录每个位置（巢箱、中间、沙坑）的产蛋数。从 0630 h 到 1330 h，每 20min 对巢箱和沙坑区进行一次即时扫描采样，以统计产蛋母鸡数量和产蛋数。在 30 s 间隔扫描期间（每个时间段 3 次扫描，共 5 个时间段），统计每个区域的啄击、威胁和驱赶行为。混合模型分析测试了处理、时间、房间、位置和层位的影响。处理对巢箱和沙坑区产蛋百分比没有显著的主效应，但 E 处理母鸡的攻击性更强（P = 0.027）。母鸡在巢箱中的产蛋数量和坐窝母鸡数量在 0830 h 至 0930 h 之间达到峰值（P < 0.0001），而在 0800 h 至 1000 h 之间，驱赶行为达到峰值（P < 0.0001）。产蛋高峰时间出现在沙坑区较晚（0930 h 至 1030 h）。处理对多数筑巢行为模式没有影响，巢箱和沙坑区的行为差异与之前的研究结果一致。海兰 W-36 母鸡似乎认为现有的巢箱令人满意，几乎没有竞争的迹象。
