不同饲养密度对地面平养蛋鸡福利状况和生产性能的影响

Effect of Different Stocking Density on Welfare Status and Production Performance of Layer Raising on Floor

试验旨在通过研究地面平养模式下不同饲养密度对蛋鸡行为、外观、血液应激指标及生产性能的影响,筛选保证蛋鸡福利状况及生产性能的最大饲养密度,为我国推广地面平养模式蛋鸡福利养殖奠定理论基础。将780只苏禽绿壳蛋鸡按舍内密度分为四组,其中地面平养分为低密度组(6只/m^2)、中密度组(8只/m^2)、高密度组(10只/m^2),笼养组为对照组,每组3个重复。试验期为18~27周龄,蛋鸡行为学数据均采用视频录像收集,在27周龄末进行翅静脉采血和福利外观评价,统计分析24~27周龄生产性能。结果显示:笼养蛋鸡的产蛋率,攻击、刻板等非福利行为均显著高于平养组(P<0.05),脚垫损伤、羽毛评分、应激激素浓度(CORT、ACTH)显著低于平养组(P<0.05)。地面平养各组间,高密度组蛋鸡料蛋比显著高于低、中密度组(P<0.05);低、中密度组蛋鸡行走和休息时间比例均显著高于高密度组(P<0.05);低密度组蛋鸡啄羽行为显著低于高密度组(P<0.05),但与中密度组差异不显著(P>0.05);低、中密度组蛋鸡脚垫损伤、背羽损伤显著低于高密度组(P<0.05);高密度组蛋鸡血清中CORT和ACTH浓度显著低于低、中密度组(P<0.05)。由此可见,平养蛋鸡比笼养蛋鸡行为表现更积极,羽毛覆盖度更好,但应激水平和足部损伤较高、生产性能较低;在试验场地模式下,推荐8只/m2为最佳饲养密度。

This experiment was conducted to investigate the effects of different stocking densities on the behavior, appearance, blood stress index and production performance of layer raising on floor, and screen the maximum rearing density with good welfare status and production performance, so as to lay a theoretical foundation for the promotion of ground feeding model of laying hens in China. Seven hundred and eighty Suqin green-eggshell layers were divided into four groups according to stocking density, three groups were raising on floor named for low-density group (6 birds/m^2), medium-density group (8 birds/m^2), high-density group (10 birds/m^2) and caged birds was the control group, with 3 replicates in each group, and the experiment period was 10 weeks (18 to 27 weeks of age). Video recording was used to collect the behavioral data of laying hens. In addition, blood collection and welfare appearance evaluation were conducted at the end of experiment, and analyzed the production performance at 24 to 27 weeks of age. As a result, compared with the control group, the laying rate and non-welfare behaviors such as aggression and stereotyping in experimental groups were significantly decreased (P<0.05), footpad damage and feather score were significantly higher (P<0.05), and the concentrations of CORT and ACTH in serum were significantly higher (P<0.05). Among 3 experimental groups, the feed-egg ratio in high-density group was significantly higher than that in low-density and medium-density groups (P<0.05), the proportion of walking and rest time in low and medium density group was significantly higher than that in high density group (P<0.05), feather pecking behavior in low density group was significantly lower than that in high density group (P<0.05) but not significantly different with medium density group (P>0.05), and the damage of footpad and back feather in low and medium density group were significantly lower than that in high density group (P<0.05). Moreover, the concentrations of CORT and ACTH in serum in high density group were significantly lower than those in low and medium density groups (P<0.05). The overall results indicated that the laying hens raising on floor had more active behaviors and better feather coverage, but had the higher stress level and injury degree of foot, and lower production performance than the control group. In the condition of experiment 8 birds/m^2 was the best stocking density.