本文選題：鴨　切入點：金黃色葡萄球菌　出處：《山東農(nóng)業(yè)大學》2015年碩士論文　論文類型：學位論文

【摘要】：鴨葡萄球菌病主要是由金黃色葡萄球菌引起的鴨的一種急性或慢性傳染病。本病主要侵害育成鴨和種鴨,以關(guān)節(jié)腫脹,關(guān)節(jié)腔內(nèi)有膿性或漿液性纖維滲出,肝臟腫大,脾臟腫大、壞死為主要特征。近年來,鴨葡萄球菌病多發(fā),對養(yǎng)鴨業(yè)造成巨大危害,加強對金黃色葡萄球菌的研究,對防治該病具有重要意義。本研究從臨床送檢的病料中分離細菌,并對其進行了培養(yǎng)特性、形態(tài)學特征、生理生化特性和分子生物學特性分析,鑒定為金黃色葡萄球菌。藥敏試驗結(jié)果顯示,分離株呈現(xiàn)不同程度耐藥,且多重耐藥現(xiàn)象比較嚴重。多數(shù)分離菌株對頭孢拉定、頭孢噻肟、米諾環(huán)素高度敏感。根據(jù)GenBank公布的金黃色葡萄球菌腸毒素基因和耐藥基因序列,設(shè)計并合成了7種腸毒素基因引物以及4種耐藥基因引物。PCR檢測結(jié)果表明,56株金黃色葡萄球菌中腸毒素G型、B型的檢出率最高,分別為32.1%、26.8%;其次是腸毒素A型、C型和H型,檢出率分別為17.9%、16.1%、16.1%;腸毒素D型和E型的檢出率低,依次為12.5%、8.9%。可見不同菌株之間腸毒素基因分布存在差異性。分離鑒定的56株金黃色葡萄球菌中,含有mecA耐藥基因的占60.7%(34/56);含有femA耐藥基因的占37.5%(21/56);含有g(shù)rlA耐藥基因的占48.2%(27/56);含有norA耐藥基因的占55.4%(31/56)。而且同一株菌能檢測出2種或2種以上耐藥基因。皮下接種金黃色葡萄球菌人工感染育成鴨,觀察鴨的臨床表現(xiàn)。接種后在不同時間內(nèi)隨機剖殺試驗組和對照組的鴨子,觀察各臟器的病理變化,并對部分組織器官進行細菌的分離鑒定。同時,采集肝臟、脾臟、腎臟、肺臟、心臟等組織進行甲醛固定、切片觀察各組織器官的病理組織學變化。結(jié)果顯示:試驗組鴨胸腹部皮下充血、出血、有膠凍樣水腫液,肝臟腫大,脾臟腫大,肺臟出血、水腫,腎臟腫大,公鴨睪丸腫大、出血。對照組鴨剖檢未見明顯病變。試驗鴨中分離的細菌與接種菌形態(tài)特征完全一致,且不同組織器官的分離率各不相同,其中關(guān)節(jié)分離率最高。病理組織學變化以肝臟脂肪變性、肝細胞壞死,脾臟淋巴細胞大量減少、脾臟壞死,腎臟空泡變性、腎小管上皮細胞壞死等為主要特征。
[Abstract]:Staphylococcosis is an acute or chronic infectious disease in ducks caused mainly by Staphylococcus aureus. It mainly affects adult ducks and breeding ducks, with swelling of the joints, exudation of purulent or serous fibers in the articular lumen, and enlargement of the liver. Splenomegaly and necrosis are the main characteristics. In recent years, staphylococcal disease in ducks is more frequent, which causes great harm to duck industry, and strengthens the research on Staphylococcus aureus. In this study, bacteria were isolated from clinical samples, and the characteristics of culture, morphology, physiology and biochemistry, and molecular biological characteristics were analyzed. Staphylococcus aureus was identified as Staphylococcus aureus. The results of drug sensitivity test showed that the isolates showed different degrees of drug resistance, and the phenomenon of multidrug resistance was serious. Most of the isolates were resistant to cefradine and cefotaxime. Minocycline is highly sensitive. According to the sequence of enterotoxin gene and drug resistance gene of Staphylococcus aureus published by GenBank, Seven enterotoxin gene primers and four drug-resistant gene primers were designed and synthesized. The results showed that the detection rate of Enterotoxin G type B was the highest in 56 strains of Staphylococcus aureus, which was 32.1% and 26.8% respectively, followed by enterotoxin A type C and H type. The detectable rates of enterotoxin D and E were lower, which were 12.5% and 8.9%, respectively. The distribution of enterotoxin gene was different among different strains. Among the 56 strains of Staphylococcus aureus isolated and identified, there were significant differences in the distribution of enterotoxin gene among them. 60.7% had mecA resistance gene, 37.5% had femA resistance gene, 48.2% had grlA resistance gene, 55.44% had norA resistance gene, and the same strain could detect two or more resistant genes. Subcutaneously inoculated staphylococcus aureus subcutaneously. Grape coccus artificially infects adult ducks, The clinical manifestations of ducks were observed. After inoculation, the ducks of the test group and the control group were killed at random, the pathological changes of each organ were observed, and some tissues and organs were isolated and identified. At the same time, liver, spleen and kidney were collected. Lung, heart and other tissues were fixed with formaldehyde. The histopathological changes of tissues and organs were observed by sections. The results showed that the experimental group had hypodermic hyperemia, hemorrhage, gelatinous edema, hepatomegaly, splenomegaly and pulmonary hemorrhage. Edema, enlargement of kidney, enlargement of testis and hemorrhage in male duck. No obvious pathological changes were found in the control group. The morphological characteristics of bacteria isolated from the tested duck were completely consistent with those of inoculation bacteria, and the isolation rates of different tissues and organs were different. The histopathological changes were mainly characterized by fatty degeneration of liver, necrosis of hepatocytes, reduction of splenic lymphocytes, necrosis of spleen, degeneration of kidney vacuoles and necrosis of renal tubular epithelial cells.
【學位授予單位】：山東農(nóng)業(yè)大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：S858.32

【參考文獻】

相關(guān)期刊論文 前1條

1 王麗華;呂殿紅;張薈;楊彪;魏文康;蔣紅霞;;質(zhì)粒介導的喹諾酮耐藥基因在動物源金黃色葡萄球菌的流行分布[J];中國獸醫(yī)學報;2014年04期

，

本文編號：1560196