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2021年,山东省临沂市一养殖场养殖的美洲鲥鱼(Alosa sapidissima)突发疾病并出现严重死亡,日死亡率高峰期达到2.5%,累积死亡率约为90%。患病鱼主要症状为体表出血、溃疡,解剖可见腹腔腹水、肝脏暗红,并伴有肠炎。组织病理学检测发现,病鱼肝脏出现弥散性坏死,嗜碱性粒细胞增多和细胞肿胀空泡变性;脾脏出现出血性贫血性坏死灶、核破裂和核固缩;肾脏淋巴细胞坏死脱落,肾小体毛细血管球萎缩,近端小管和远端小管内的细胞出现不同程度的细胞结构消失。发病鱼肉眼和显微镜观察未见明显寄生虫,利用PCR方法检测鲤疱疹病毒2型(Cyprinid herpesvirus 2)、鲈鱼蛙病毒(largemouth bass ranavirus)等淡水鱼类常见病毒均为阴性。细菌分离培养结果显示,从发病鱼的肝脏、肾脏和脾脏中分离得到形态一致的优势菌,命名为AS-AH2101。经16S rRNA测序比对和生理生化鉴定,确定AS-AH2101为嗜水气单胞菌(Aeromonas hydrophila)。毒力基因检测结果显示,AS-AH2101携带气溶素(aerA)、溶血素(hlyA)、丝氨酸蛋白酶(ahpA)、... 相似文献
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黄芪多糖对内毒素诱发大鼠实验性乳腺炎的影响 总被引:1,自引:0,他引:1
选取40只SD雌性大鼠使之交配受孕。在确定其怀孕后,30只孕鼠随机分成正常对照组、阳性对照组和试验组,每组10只。试验组大鼠每天按100 mg/kg体重灌喂黄芪多糖(APS),直至试验结束,而对照组大鼠灌喂相应体积的生理盐水(PSS)。孕鼠于产后72 h分别用灭菌PSS和50μg大肠杆菌内毒素经乳头管灌注到大鼠第4对乳腺内。灌注后24 h处死大鼠,取乳腺组织和颈静脉血进行指标测定。结果显示,阳性对照组大鼠乳腺组织中肿瘤坏死因子α(TNF-α)浓度、N-乙酰-β-D-氨基葡萄糖苷酶(NAGase)活性,与正常对照组相比显著升高(P<0.05);试验组大鼠乳腺组织中TNF-α浓度、NAGase活性与阳性对照组相比,显著降低(P<0.05)。结果表明,灌喂APS可以抑制乳腺组织内炎性细胞因子TNF-α的过度释放,对内毒素诱发的大鼠实验性乳腺炎有一定的保护作用。 相似文献
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Repeated fertilizer applications to cultivated soils may alter the composition and activities of microbial communities in terrestrial agro-ecosystems. In this study, we investigated the effects of different long term fertilization practices (control (CK), three levels of mineral fertilizer (N1P1K1, N2P2K2, and N3P3K3), and organic manure (OM)) on soil environmental variables and microbial communities by using phospholipid fatty acid (PLFA) biomarkers analysis in subtropical China. Study showed that OM treatment led to increases in soil organic carbon (SOC), total nitrogen (TN) and total phosphorus (TP) contents, while the mineral fertilizer treatment led to increases in dissolved organic carbon (DOC) content. Changes in soil microbial communities (eg. bacteria, actinomycetes) were more noticeable in soils subjected to organic manure applications than in the control soils or those treated with mineral fertilizer applications. Fungal PLFA biomarkers responded differently from the other PLFA groups, the numerical values of fungal PLFA biomarkers were similar for all the OM and mineral fertilizer treatments. PCA analysis showed that the relative abundance of most PLFA biomarkers increased in response to OM treatment, and that increased application rates of the mineral fertilizer changed the composition of one small fungal PLFA biomarker group (namely 18:3ω6c and 16:1ω5c). Further, from the range of soil environmental factors that we examined, SOC, TN and TP were the key determinants affecting soil microbial community. Our results suggest that organic manure should be recommended to improve soil microbial activity in subtropical agricultural ecosystems, while increasing mineral fertilizer applications alone will not increase microbial growth in paddy soils. 相似文献
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An investigation of the aetiological role of bovine herpesvirus 4 in bovine endometritis 总被引:2,自引:0,他引:2
Fábián K Makrai L Sachse K Szeredi L Egyed L 《Veterinary journal (London, England : 1997)》2008,177(2):289-292
Uteri from 31 infertile cattle were examined for the presence of bovine herpesvirus 4 (BoHV-4) by nested polymerase chain reaction (PCR). Samples were also tested for bacteria, including chlamydiae and Mycoplasma bovis. BoHV-4 was detected by PCR in 27/31 (87.1%) samples, but the presence and amount of viral DNA was not correlated with histological and bacteriological findings. Arcanobacterium pyogenes, Histophilus somni and Pasteurella multocida were isolated from five cows with endometritis. Chlamydiae were detected in four cases (12.9%), but only two of these had endometritis. The study does not support a role for BoHV-4 as primary agent in bovine endometritis. 相似文献
108.
C.B. Magnusson K.P. Poulsen J.A. Budde F.A. Hartmann N.A. Aulik S.M. Raabis A.S.D. Moreira B.J. Darien S.F. Peek 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):469-473
Background
Periodic lack of availability and high cost of commercially produced isotonic fluids for intravenous (IV) use in horses have increasingly led to use of home‐made or commercially compound fluids by veterinarians. Data regarding the quality control and safety of compounded fluids would be of benefit to equine veterinarians.Objectives
To compare electrolyte concentrations, sterility, and endotoxin contamination of commercially available fluids to 2 forms of compounded isotonic crystalloid fluids intended for IV use in horses.Methods
Prospective study. Two methods of preparing compounded crystalloids formulated to replicate commercial Plasma‐Lyte A (Abbott, Chicago, IL) were compared. One formulation was prepared by a hand‐mixed method involving chlorinated drinking water commonly employed by equine practitioners, and the other was prepared by means of ingredients obtained from a commercial compounding pharmacy. The variables for comparison were electrolyte concentrations, sterility, and presence of endotoxin contamination.Results
Electrolyte concentrations were consistent within each product but different between types of fluids (P < 0.0001). Hand‐mixed fluids had significantly more bacterial contamination compared to commercial Plasma‐Lyte A (P = 0.0014). One of the hand‐mixed fluid samples had detectable endotoxin contamination.Conclusions and Clinical Importance
Chlorinated drinking water is not an acceptable source of water to compound isotonic fluids for IV administration. Equine practitioners should be aware of this risk and obtain the informed consent of their clients. 相似文献109.
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