PDF(Pubmed)
Abstract：
Femoral head necrosis (FHN) in broilers is a common leg disorder in intensive poultry farming, giving rise to poor animal health and welfare. Abnormal mechanical stress in the hip joint is a risk factor for FHN, and articular cartilage is attracting increasing attention as a cushion and lubrication structure for the joint. In the present study, broilers aged 3 to 4 wk with FHN were divided into femoral head separation (FHS) and femoral head separation with growth plate lacerations (FHSL) groups, with normal broilers as control. The features of the hip joint, bone, and cartilage were assessed in FHN progression using devices including computed tomography (CT), atomic force microscope (AFM), and transmission electron microscopy (TEM). Broilers with FHN demonstrated decreased bone mechanical properties, narrow joint space, and thickened femoral head stellate structures. Notably, abnormal cartilage morphology was observed in FHN-affected broilers, characterized by increased cartilage thickness and rough cartilage surfaces. In addition, as FHN developed, cartilage surface friction and friction coefficient dramatically increased, while cartilage modulus and stiffness decreased. The ultramicro-damage occurred in chondrocytes and the extracellular matrix (ECM) of cartilage. Cell disintegration, abnormal mitochondrial accumulation, and oxidative stress damage were observed in chondrocytes. A notable decline in cartilage collagen content was observed in ECM during the initial stages of FHN, accompanied by a pronounced reduction in collagen fiber diameter and proteoglycan content as FHN progressed. Furthermore, the noticeable loosening of the collagen fiber structure and the appearance of type I collagen were noted in cartilage. In conclusion, there was a progressive decrease in bone quality and multifaceted damage of cartilage in the femoral head, which was closely linked to the severity of FHN in broilers.
摘要：
肉鸡的股骨头坏死（FHN）是集约化家禽养殖中常见的腿部疾病，导致动物健康和福利不佳。髋关节的异常机械应力是FHN的危险因素，关节软骨作为关节的缓冲和润滑结构越来越受到关注。在本研究中,将FHN3至4周龄的肉鸡分为股骨头分离（FHS）和股骨头分离伴生长板撕裂（FHSL）组，以正常肉鸡为对照。髋关节的特征，骨头,使用包括计算机断层扫描（CT）在内的设备评估FHN进展和软骨，原子力显微镜(AFM),和透射电子显微镜（TEM）。FHN的肉鸡骨力学性能下降，狭窄的接缝空间，股骨头星状结构增厚。值得注意的是,在受FHN影响的肉鸡中观察到异常的软骨形态，以软骨厚度增加和软骨表面粗糙为特征。此外,随着FHN的发展，软骨表面的摩擦和摩擦系数急剧增加，而软骨模量和刚度下降。超微损伤发生在软骨细胞和软骨的细胞外基质（ECM）中。细胞崩解,异常的线粒体积累，在软骨细胞中观察到氧化应激损伤。在FHN的初始阶段，ECM中观察到软骨胶原蛋白含量显着下降，随着FHN的进展，胶原纤维直径和蛋白聚糖含量显着降低。此外，在软骨中观察到胶原纤维结构明显松动和I型胶原的出现。总之,股骨头的骨质量逐渐下降，软骨受到多方面的损伤，这与肉鸡FHN的严重程度密切相关。
