COMPARISON OF THE PATHOGENICITY OF 2 US PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS ISOLATES WITH THAT OF THE LELYSTAD VIRUS
COMPARISON OF THE PATHOGENICITY OF 2 US PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS ISOLATES WITH THAT OF THE LELYSTAD VIRUS
复制标题
DOI：
10.1177/030098589503200606
复制
发表时间：
1995-11-01
影响因子：
2.4
通讯作者：
RATHJE, JA
中科院分区：
文献类型：
--
作者：
HALBUR, PG;PAUL, PS;RATHJE, JA
将莱利斯塔德病毒或猪繁殖与呼吸综合征病毒的两种美国分离株（VR2385、VR2431）之一鼻内给予 25 只 4 周龄、剖腹产且缺乏初乳的猪。在接种后1、2、3、5、7、10、15、21或28天对这些组的猪进行尸检。莱利斯塔德病毒和 VR2431 引起轻度短暂发热、呼吸困难和呼吸急促。 VR2385 引起腹式呼吸困难、快速、发热、嗜睡、厌食和斑片状皮肤发绀。接种后 10 天，所有三种分离株均诱导出现多灶性棕褐色斑驳实变，涉及莱利斯塔德 (Lelystad) 的 6.8% (n = 9, SEM = 3.4) 肺部、VR2431 的 9.7% (n = 9, SEM = 2.7) 肺部和 VR2385 的 54.2% (n = 9, SEM = 4.4) 肺部。特征性的微观肺部病变包括2型肺细胞肥大和增生、肺泡腔内坏死碎片和混合炎症细胞增多，以及肺泡间隔单核细胞浸润。淋巴结肿大伴滤泡肥大、增生和坏死。类似的滤泡病变也见于派尔氏淋巴结和扁桃体。所有三种分离株均再现了淋巴组织细胞性心肌炎和脑炎。接种 VR2385 的猪的临床呼吸系统疾病以及肉眼和显微镜下肺部病变评分明显更加严重。在 28 天的研究中，这三种病毒都很容易从血清、肺和扁桃体中分离出来。淋巴系统和呼吸系统具有最显着的病变，并且似乎是这些病毒复制的主要部位。这项工作证明了猪繁殖与呼吸综合征分离株的致病性存在显着差异。
The Lelystad virus or one of two US isolates (VR2385, VR2431) of porcine reproductive and respiratory syndrome virus were given intranasally to 25 4-week-old cesarian-derived colostrum-deprived pigs. Pigs from these groups were necropsied at 1, 2, 3, 5, 7, 10, 15, 21, or 28 days postinoculation. The Lelystad virus and VR2431 induced mild transient pyrexia, dyspnea, and tachypnea. VR2385 induced labored and rapid abdominal respiration, pyrexia, lethargy, anorexia, and patchy dermal cyanosis. All three isolates induced multifocal tan-mottled consolidation involving 6.8% (n = 9, SEM = 3.4) of the lung for Lelystad, 9.7% (n = 9, SEM = 2.7) of the lung for VR2431, and 54.2% (n = 9, SEM = 4.4) of the lung for VR2385 at 10 days postinoculation. Characteristic microscopic lung lesions consisted of type 2 pneumocyte hypertrophy and hyperplasia, necrotic debris and increased mixed inflammatory cells in alveolar spaces, and alveolar septal infiltration with mononuclear cells. Lymphadenopathy with follicular hypertrophy, hyperplasia, and necrosis was consistently seen. Similar follicular lesions were also seen in Peyer's patches and tonsils. Lymphohistiocytic myocarditis and encephalitis were reproduced with all three isolates. Clinical respiratory disease and gross and microscopic lung lesion scores were considerably and significantly more severe in the VR2385-inoculated pigs. All three viruses were readily isolated from sera, lungs, and tonsils throughout the 28 days of the study. The lymphoid and respiratory systems have the most remarkable lesions and appear to be the major site of replication of these viruses. This work demonstrated a marked difference in pathogenicity of porcine reproductive and respiratory syndrome isolates.