西藏牦牛源牛支原体病本种动物模型的建立

Establishment of Animal Model of Bovine Mycoplasma from Yaks in Tibet

为了在高原环境下建立牦牛源牛支原体病本种动物模型。采用鸡胚、家兔、犊牦牛对牛支原体进行菌株复壮效果验证,并将3个复壮株分别进行犊牦牛回归试验;通过临床症状观察、病理组织学观察等方法,以评价牦牛源牛支原体病动物模型效果,明确鸡胚、家兔能否作为牛支原体的复壮载体。结果显示,3个不同载体复壮株接种犊牦牛后,均出现体温升高、咳嗽、流涕、体重增长缓慢等临床症状,呈间歇性排菌,第7 d可检测到牛支原体抗体,且持续存在。剖检发现其肺组织呈现不同程度的损伤,主要以弥散性充血、出血、淤血、干酪样坏死为主要特征,病理组织学发现肺泡出现萎缩、塌陷,肺泡壁增厚,部分炎症细胞浸润等病理变化。本试验证明鸡胚、家兔均可作为牛支原体的复壮载体,且成功建立了牦牛源牛支原体病本种动物模型。

In order to establish a native animal model of Mycoplasma bovis infection derived from yaks in high-altitude plateau environment,we conducted strain rejuvenation validation experiments using chicken embryos,rabbits,and calf yaks.Subsequently,the three rejuvenated strains were tested through regression experiments in calf yaks.Clinical symptoms,pathological histology,and other methods were employed to assess the effectiveness of the yak-origin Mycoplasma bovis animal model and to determine whether chicken embryos and rabbits could serve as suitable rejuvenation vectors for Mycoplasma bovis.The results revealed that following inoculation of calf yaks with the three different rejuvenated strains,clinical symptoms such as elevated body temperature,coughing,nasal discharge,and slow weight gain were observed.These symptoms were accompanied by intermittent shedding of Mycoplasma bovis,and the presence of Mycoplasma bovis antibodies was detectable as early as the 7th day and persisted.Post-mortem examinations demonstrated varying degrees of lung tissue damage,characterized primarily by diffuse congestion,hemorrhage,congestion,and caseous necrosis.Histological analyses revealed pathological changes in lung alveoli,including atrophy,collapse,thickening of alveolar walls,and infiltration of inflammatory cells.This study confirmed that both chicken embryos and rabbits effectively served as rejuvenation vectors for Mycoplasma bovis.Furthermore,it successfully established a native animal model of Mycoplasma bovis infection derived from yaks,suitable for research in high-altitude plateau environments.