Yu Yaling, Zhang Yanyan, Jiang Yixin, Ge Hongfan, Yang Chengbo, Zhou Zhenlei
Department of Veterinary Clinical Sciences, Nanjing Agricultural University, Nanjing, China.
Department of Animal Science, University of Manitoba, Winnipeg, CanadaR3T 2N2.
J Anim Sci. 2025 Jan 4;103. doi: 10.1093/jas/skaf147.
Broilers in modern farming systems gain significant body weight, resulting in leg disorders in broilers. Long bones in the limbs extend after birth through endochondral ossification (EO), a process where bone replaces cartilage in pre-formed templates, making it essential for bone and cartilage development. The endoplasmic reticulum stress (ERS) pathway has been implicated in bone development and key steps of EO, but the mechanism remains unclear. In this study, broilers were reared on wire flooring to induce persistent footing instability and physiological stress. Salubrinal (SAL), an ERS inhibitor, was administrated to explore its effects on bone disorders. Parameters such as weight, length, bone mineral density, and strength were measured to assess bone and cartilage integrity in broilers. And staining and gene expression detection were performed to explore the effects of ERS on EO. The results indicated that broilers raised on wire flooring had an increased incidence of severe gait defects and bone disorders, especially femoral head necrosis. Meanwhile, broilers on wire flooring had increased chondrocyte hypertrophy and apoptosis, vascularity, and trabecularity, along with impaired cartilage and disrupted bone remodeling, all of which are key activators of EO. SAL treatment could inhibit EO by reducing chondrocyte apoptosis, vascular invasion, and bone resorption in broilers on wire flooring. Overall, this study highlights the negative effects of wire flooring on bone and cartilage, which are closely related to the occurrence of bone disease. Additionally, it suggests that blocking ERS may protect broilers from poor flooring conditions by regulating EO.
现代养殖系统中的肉鸡体重显著增加，导致肉鸡出现腿部疾病。四肢的长骨在出生后通过软骨内成骨（EO）生长，这一过程中骨在预先形成的模板中替代软骨，对骨和软骨的发育至关重要。内质网应激（ERS）途径与骨发育及EO的关键步骤有关，但其机制尚不清楚。在本研究中，将肉鸡饲养在金属网上以诱导持续的足部不稳定和生理应激。给予ERS抑制剂沙芦比诺（SAL）以探究其对骨骼疾病的影响。测量体重、长度、骨矿物质密度和强度等参数以评估肉鸡的骨和软骨完整性。并进行染色和基因表达检测以探究ERS对EO的影响。结果表明，饲养在金属网上的肉鸡严重步态缺陷和骨骼疾病的发生率增加，尤其是股骨头坏死。同时，饲养在金属网上的肉鸡软骨细胞肥大、凋亡、血管生成和骨小梁增加，伴有软骨受损和骨重塑紊乱，所有这些都是EO的关键激活因素。SAL处理可通过减少饲养在金属网上的肉鸡的软骨细胞凋亡、血管侵入和骨吸收来抑制EO。总体而言，本研究突出了金属网对骨和软骨的负面影响，这与骨病的发生密切相关。此外，研究表明阻断ERS可能通过调节EO来保护肉鸡免受不良饲养条件影响。
