屠宰生猪肺脏病变评估及PRRSV感染状况的调查分析

发布时间：2018-03-11 11:16

本文选题：屠宰生猪　切入点：肺脏病变　出处：《山东农业大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,我国大多数猪场正遭受着越来越严重的呼吸系统疾病的困扰,在多种非生物性致病因素诱发或协同作用下由多种病原微生物混合感染引起的猪呼吸道综合征(PRDC)的比例在逐年升高,猪呼吸系统疾病已成为严重危害生猪尤其是保育-育肥猪健康生长的最重要因素,给我国养猪业带来了严重的经济损失。猪呼吸系统疾病常造成难以修复的器质性病变,通过对屠宰生猪肺脏病变的检测评估,可以了解生猪宰前肺脏的健康状况、曾患疾病及严重程度,并对感染病原进行检测分析,进而掌握猪群呼吸系统疾病的发生和流行状况,便于对调查猪群或区域内生猪呼吸系统疾病进行回顾性诊断,并提出针对性的防控措施。为了解泰安及其周边地区中小规模猪场屠宰生猪的肺脏及胸膜病变和PRRSV的感染状况,对来自该区域屠宰生猪的肺脏进行图像采集和眼观病变评估打分,结合组织病理学检查,对屠宰生猪肺脏及胸膜病变进行系统的分类和统计分析,并比较不同规模及不同饲养模式下(外购仔猪育肥场、低于100头母猪和100头母猪以上自繁自养场)出栏生猪的肺脏健康状况。另外,对肺炎病变明显的肺组织及其肺门淋巴结进行PRRSV检测,以了解泰安及其周边地区屠宰生猪群PRRSV的感染带毒状况。2014年10-12月份于泰安某规模化生猪屠宰场进行了肺脏及胸膜健康状况检测评估及采样,共检测评估了外购仔猪育肥场(A)、小于100头母猪规模的自繁自养场(B)和100-300头母猪的自繁自养场(C)三种类型猪场的15个生猪群、750头生猪肺脏,采集了具有明显肺炎病变的肺脏和肺门淋巴结组织样品75份。研究结果表明:513个肺脏具有明显病变,病变检出率高达68.4%(513/750),各肺脏平均病变等级为2.54。在513个病变肺脏中,单一性病变的占26.7%(137/513),两种及两种以上病变的占73.3%(376/513);三种类型猪场(A,B,C)生猪肺脏病变检出率分别为77.2%(193/250)、65.2%(163/250)和62.8%(157/250);肺脏病变的类型主要有各种类型的肺炎、出血、淤血、水肿、气肿等,其中以肺炎病变比例最高,达53.4%(274/513),其次为肺出血、淤血,病变比例为32.8%(168/513),肺气肿病变比例为11.3%(58/513)。利用屠宰猪胸膜炎评估系统(SPES)对750头生猪胸膜病变进行了量化评估,结果表明:胸膜炎检出率高达48.7%,三种类型猪场胸膜炎发生比例及平均等级分别为56.0%、1.02,46.4%、0.81,43.6%、0.64。研究结果表明,绝大多数屠宰生猪的肺脏具有明显病变,病变比例最高的为各种类型的肺炎,其中以间质性肺炎最为常见,另外,肺脏病变兼有胸膜炎的发生亦较为普遍;外购仔猪育肥场肺脏病变较自繁自养场严重,不同规模自繁自养场的生猪肺脏病变程度差异不大。通过RT-PCR方法检测75份组织样品PRRSV的感染状况,并采用免疫组织化学方法对相应的肺组织进行免疫组织化学检测。9份病料呈PRRSV检测阳性,阳性率为12.0%(9/75),对应肺脏组织的免疫组织化学检测均呈阳性反应。RT-PCR产物经胶回收、连接、转化,测序,结果表明,9个PRRSV分离株与TJ、HuN、JXA1等参考株处于同一分支,属于同一亚群,亲缘关系较近;Nsp2高变区基因推导的氨基酸序列比较结果表明,9个分离株均存在30个氨基酸的缺失,另外,部分分离株在其它个别位点亦出现了突变。PRRSV在不断的变异和演化,其在一定时期内仍是严重制约我国养猪业健康发展的头号疫病。
[Abstract]:In recent years, the majority of farms in our country are suffering more and more serious respiratory diseases, to induce a variety of non biological pathogenic factors or synergistic effects by a variety of pathogenic microorganisms caused by combined infection of porcine respiratory syndrome (PRDC) in the proportion increased year by year, porcine respiratory disease has become a serious threat to the pig especially conservation education - the most important factor of the healthy growth of pigs, caused serious economic losses to the swine industry in China. Swine respiratory diseases often cause organic lesions difficult to repair, the detection and evaluation of slaughtered pig lung lesions, can understand the health status of pre slaughter pig lung, suffered from disease and severity, and the infection pathogen detection and analysis, and then grasp the swine respiratory disease occurrence and epidemic situation, in order to investigate herd or area respiratory disease of pigs in the past The diagnosis, and put forward the corresponding prevention and control measures. To understand the infection status of Tai'an and its surrounding areas of small and medium scale pig farm pig slaughter of lung and pleural lesions and PRRSV, from the area of slaughtering pigs lung image acquisition and eye view lesion scoring, combined with pathological examination, classification and statistical analysis system the slaughtered pig lung and pleural lesions, and compare the different scale and different feeding mode (purchased piglets feedlot, more than 100 sows and 100 sows Farrow field) slaughter pigs lung health. In addition, the detection of PRRSV pneumonia lesions of lung tissue and pulmonary hilar lymph nodes. In order to understand the slaughter of Tai'an and the surrounding area of PRRSV virus infection among students in.2014 years 10-12 months in Tai'an in a large-scale pig slaughterhouse of lung and pleural health inspection Evaluation and sampling, detection and evaluation were purchased piglet fattening farm (A), less than 100 sows Farrow field scale (B) and 100-300 sows Farrow field (C) of 15 students among three types of farms, 750 pig lungs were collected with obvious pneumonia lesions of the lung hilar lymph nodes and 75 tissue samples. The results show that: 513 lung lesions have obvious lesions, the detection rate of 68.4% (513/750), the average grade of 2.54. lung lesions in 513 lesions in the lung, single lesions accounted for 26.7% (137/513), two and above two of the lesions 73.3% (376/513); three types of farms (A, B, C) of pig lung lesions were detected in 77.2% (193/250), 65.2% (163/250) and 62.8% (157/250); the type of lung lesions are mainly various types of pneumonia, hemorrhage, congestion, edema, emphysema and pneumonia, with the highest proportion of lesions 53.4% (274/513). Secondly, pulmonary hemorrhage, congestion, lesions accounted for 32.8% (168/513), emphysema lesion accounted for 11.3% (58/513). The pig slaughter assessment system (SPES) of pleurisy in 750 pigs pleural lesions was assessed. The results show that the pleurisy detection rate as high as 48.7%, three types of farms and the average incidence rate of pleurisy grades were 56%, 1.02,46.4%, 0.81,43.6%, 0.64. results show that the vast majority of slaughtered pig lung lesions have obvious lesions, the highest proportion of various types of pneumonia, with interstitial pneumonia is the most common, in addition, the occurrence of lung lesions with pleurisy is also common; outsourcing of fattening pigs lung lesions than from the field Farrow serious, since the degree of difference between the different scale pig lung lesions Farrow field. Through the RT-PCR method for the detection of 75 samples of PRRSV infection, and using immunohistochemistry Methods immunohistochemical detection of.9 disease of the corresponding lung tissue material was PRRSV positive, the positive rate was 12% (9/75), immunohistochemical detection of corresponding lung tissue showed.RT-PCR positive reaction product by gel extraction, connection, transformation, sequencing results showed that 9 isolates of PRRSV and TJ. HuN, JXA1 and other reference strains in the same branch, belong to the same subgroup, with close genetic relationship; the amino acid sequence of the hypervariable region of Nsp2 gene is missing, the comparison results show that the 9 strains there were 30 amino acids in some isolates in other individual loci also appeared in mutation and.PRRSV mutation evolutionary, it is still in a certain period of time seriously restrict the healthy development of pig industry in China's top blight.

【学位授予单位】：山东农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S858.28

【引证文献】