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81.
Staphylococcus aureus septicaemia was diagnosed in a dead, stranded harbour porpoise from the German Baltic Sea and in a live harbour porpoise by-caught in inner Danish waters and taken into captivity. Lesions included pyogranulomatous myocarditis, necrotising suppurative bronchopneumonia, pyelonephritis, osteomyelitis and leptomeningitis, and abscesses in lymph nodes and skeletal muscles. The captive animal had fibrinous suppurative epicarditis and pyogranulomatous myocarditis with abscesses. In both animals the organism was suspected to have entered through skin lesions or via the respiratory tract.  相似文献   
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Herpes simplex virus-1 (HSV-1) based amplicon vectors are promising gene delivery vehicles because they have a large transgene capacity and can efficiently transduce many different cell types, including non-dividing cells, of various animal species. The Circ protein of bovine herpesvirus-1 (BHV-1) is a myristylated virion component of unknown function. Preliminary experiments with a circ gene deletion mutant indicated that Circ may influence the host's immune response by downregulating MHC-II expression in bovine monocytes. To get more insight into the function of Circ, amplicon vectors were constructed with various open reading frames (ORFs) under the control of the HSV-1 IE4/5 promoter: (i) the Circ ORF alone, (ii) a fusion ORF encoding an N-terminal Circ fused to the enhanced green fluorescent protein (eGFP), (iii) the eGFP ORF alone, and (iv) the Circ ORF in the inverted orientation. Upon helpervirus-free packaging into HSV-1 amplicon particles and transduction of Vero cells, both Circ alone and the Circ-eGFP fusion protein produced a punctate pattern within the cytoplasm, suggesting membrane association of the myristylated protein. In contrast, eGFP alone was evenly distributed over the cytoplasm of transduced cells. Upon infection of bovine buffy-coat cells, it was observed that cells of the monocyte lineage but not lymphocytes were transduced. Transgene expression reached a peak around 20h after transduction and lasted for at least 90h. Transduced monocytes underwent specific morphological changes, which may be attributed to Circ synthesis.  相似文献   
84.
Future prophylaxis needs new concepts, including natural disease resistance of hosts against infectious agents. Genomic approaches to detect and improve disease resistance in farm animals and the molecular mechanisms involved in host-parasite interactions depend to a high degree on the trait differences between founder breeds, i.e. on the animal model. The present study evaluates differences in susceptibility/resistance against Sarcocystis miescheriana in the European Pietrain (PI) and the Chinese Meishan (ME) pig breeds, based on 25 individuals, infected orally with 5x10(4) sporocysts of S. miescheriana. Significant differences appeared in clinical, serological, haematological and parasitological findings. The major discriminating period post infection (p.i.) was between days 42 and 45. Severity of signs was negatively correlated with specific immunoglobulin titres during the first 3 weeks p.i. and positively with the load of bradyzoites in muscle tissues of the pigs. Loads of bradyzoites in muscle tissues were 20 times higher in PI than in ME. Sarcocystis-specific differences between the two breeds were in the range of 1-2 standard deviations. The study lays the foundation for further experiments to analyse chromosomal regions, candidate genes, and thus the molecular basis of Sarcocystis susceptibility/resistance as a model for host-parasite interaction in protozoan infectious disease.  相似文献   
85.
Trypanosoma cruzi-like flagellates were incidentally noted in blood smears of a routinely monitored rhesus monkey experimentally infected with the simian immunodeficiency virus (SIV). Immunodeficiency in the course of the SIV infection reactivated a chronic infection of Chagas' disease that had been unnoticed when the macaque was imported to Europe. The animal developed no specific clinical symptoms of American trypanosomiasis, but histologically a chagasic myocarditis was detected. Analysis of the small subunit rRNA gene of the trypanosome identified the protozoan as T. cruzi.  相似文献   
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Control and eradication programs of brucellosis in cattle, sheep, goats and pigs have been more or less successfully implemented within the Member States (MS) of the European Union (EU) and Norway after Word War II. As a result, the epidemiological situation of animal brucellosis is extremely diverse among different MS or regions within a MS and among the different animal species. Some MS, mainly North European countries, and Norway are declared “officially bovine brucellosis free” and/or “officially ovine and caprine (Brucella melitensis) free”. The situation is less favorable in Southern European countries, particularly as far as sheep and goat brucellosis are concerned. This situation has important zoonotic consequences as reflected in the number of human brucellosis cases due to B. melitensis that are still encountered in those countries. Brucellosis in swine has re-emerged as a result of spillover from the wild boar brucellosis (Brucella suis biovar 2) reservoir, particularly in outdoor reared pigs. Besides the actual challenge to eradicate brucellosis, further issues have to be addressed: (1) the management of false positive serological results that occur in the course of brucellosis testing, particularly in cattle; (2) the impact of wildlife brucellosis, particularly wild boar brucellosis in domestic animals; and (3) the importance of B. melitensis infection in cattle that are in contact with infected sheep.  相似文献   
88.
The performance of a Fleisch No. 5 pneumotachometer (F), and two commercial ultrasonic pneumotachometers, the BRDL (B) and the Spiroson (S) systems were compared in respect to their use for determination of ventilatory parameters at rest and during lobeline-induced hyperpnoea. Five clinically healthy Thoroughbred horses were tested with the three pneumotachometers in random order. Respiratory airflow, respired gas concentrations, oesophageal pressures, pressures within the mask systems and arterial blood gases were determined before and during lobeline-induced hyperpnoea. Because measured peak expiratory airflow rates exceeded the stated linear range of the Fleisch pneumotachometer ( approximately +/- 25 l s(-1)) differential pressure-flow curves were determined in vitro over the range of flows recorded in vivo. Expired flows greater than the linear range were corrected according to the derived regression equation. No differences in any of the measured variables among the three systems were present at rest. At peak ventilation of lobeline-induced hyperpnoea mask pressures [Delta P(mask)(mean (SEM)): F: 9.6 (2.8) cm H(2)O, B: 0.8 (0.4) cm H(2)O, S: 1.4 (0.8) cm H(2)O] and end tidal carbon dioxide [ ET CO(2)(mean (SEM)): F: 2. 6 (0.1)%, B: 2.1 (0.2)%, S: 2.1 (0.1)%] were significantly higher in system F. Despite a tendency for respiratory frequency and peak inspired and expired flows, to be lower with system F, no significant differences in the measurements of ventilatory mechanics were detected. In conclusion, the ultrasonic flowmeters pose significantly lower resistive loads onto the respiratory system during ventilation above resting levels than Fleisch No 5 pneumotachometers. However, at the flowrates achieved during lobeline-induced hyperpnoea an in vitro calibration of the differential pressure-flow relationship allows correction for expiratory alinearity in system F. In addition, the performance of the Spiroson flowmeter is accurate in determining ventilatory mechanics at rest and during lobeline-induced hyperpnoea.  相似文献   
89.
This report describes the findings in a four-year-old Toggenburg goat with demodicosis. The skin had multifocal nodules, which were approximately 5 mm in diameter and contained thick yellow exsudate. Microscopic examination of the exsudate revealed numerous Demodex caprae. The goat was clipped and treated topically every five to seven days for a total of 12 treatments with a 1:100 dilution of amitraz (Ectodex, Hoechst Roussel Vet). The treatment resulted in a marked decrease in the number of skin nodules. However, new nodules appeared after treatment was discontinued and complete clinical cure was not achieved.  相似文献   
90.
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