Wageningen Livestock Research, Wageningen University and Research, 6700 AH Wageningen, the Netherlands.
Wageningen Livestock Research, Wageningen University and Research, 6700 AH Wageningen, the Netherlands.
Poult Sci. 2023 May;102(5):102603. doi: 10.1016/j.psj.2023.102603. Epub 2023 Feb 21.
There is an increasing trend toward broiler production systems with higher welfare requirements. Breed and stocking density are considered key factors for broiler welfare that are often specified as criteria for such higher welfare systems. However, it remains unknown how slower-growing broilers respond to a reduction in stocking density with regard to their welfare and performance, and whether this response differs from fast-growing broilers. Therefore, we compared fast- (F) and slower-growing broilers (S) housed at 4 different stocking densities (24, 30, 36, and 42 kg/m, based on slaughter weight) and measured their welfare scores (i.e., gait, footpad dermatitis, hock burn, skin lesions and cleanliness), litter quality and performance. The experiment had a 2 × 4 factorial design with 4 replicates (pens) per treatment (32 pens in total). Thinning (15%) was done in a 50/50 male/female ratio at 38 (F) and 44 (S) d of age (estimated body weight of 2.2 kg). We hypothesized that breeds would respond differently to a reduction in stocking density. Contrary to our hypothesis, only one interaction between breed and stocking density was found on footpad dermatitis, indicating that fast- and slower-growing broilers generally showed similar responses to a reduction in stocking density. F broilers showed a steeper decline in the prevalence of footpad dermatitis with reducing stocking density compared to S broilers. Broilers housed at lower stocking densities (24 and/or 30 kg/m) showed improved welfare measures, litter quality and performance compared to those housed at higher stocking densities (36 and/or 42 kg/m). S broilers had better welfare scores (gait, footpad dermatitis and skin lesions), litter quality and lower performance compared to F broilers. In conclusion, reducing stocking density improved welfare of both F and S broilers, but more for F broilers in case of footpad dermatitis, and using S broilers improved welfare compared to F broilers. Reducing stocking density and using slower-growing broilers benefits broiler welfare, where combining both would further improve broiler welfare.
肉鸡生产系统越来越倾向于提高福利要求。品种和饲养密度被认为是影响肉鸡福利的关键因素，通常作为更高福利系统的标准。然而，对于生长速度较慢的肉鸡而言，降低饲养密度对其福利和性能的影响，以及这种反应是否与生长速度较快的肉鸡不同，目前尚不清楚。因此，我们比较了在 4 种不同饲养密度（基于屠宰体重，分别为 24、30、36 和 42kg/m2）下饲养的快（F）和慢（S）生长型肉鸡，并测量了它们的福利评分（即步态、脚垫皮炎、跗关节烧伤、皮肤损伤和清洁度）、垫料质量和性能。该实验采用 2×4 因子设计，每个处理有 4 个重复（鸡舍）（总共 32 个鸡舍）。在 38（F）和 44（S）日龄（估计体重为 2.2kg）时，以 50/50 的公母比例进行疏苗（15%）。我们假设品种对饲养密度的降低会有不同的反应。与我们的假设相反，仅在脚垫皮炎方面发现了品种和饲养密度之间的一个相互作用，表明快生长型和慢生长型肉鸡通常对饲养密度的降低有相似的反应。与慢生长型肉鸡相比，F 型肉鸡随着饲养密度的降低，脚垫皮炎的患病率呈陡峭下降。与饲养在较高饲养密度（36 和/或 42kg/m2）的肉鸡相比，饲养在较低饲养密度（24 和/或 30kg/m2）的肉鸡表现出更好的福利指标、垫料质量和性能。与 F 型肉鸡相比，S 型肉鸡的福利评分（步态、脚垫皮炎和皮肤损伤）、垫料质量更好，性能更低。总之，降低饲养密度提高了 F 型和 S 型肉鸡的福利，但对于 F 型肉鸡而言，在脚垫皮炎方面的改善更为明显，而使用 S 型肉鸡比使用 F 型肉鸡提高了福利。降低饲养密度和使用生长速度较慢的肉鸡有利于提高肉鸡福利，而将两者结合使用将进一步提高肉鸡福利。
