Cellular and humoral local immune responses in sheep experimentally infected with Oestrus ovis (Diptera: Oestridae)     

Tabouret G  Lacroux C  Andreoletti O  Bergeaud JP  Hailu-Tolosa Y  Hoste H  Prevot F  Grisez C  Dorchies P  Jacquiet P 《Veterinary research》2003,34(2):231-241

Cellular and humoral local responses were investigated following repetitive artificial Oestrus ovis infections in lambs. The presence of larvae induced a huge local recruitment of either leucocytes (T and B lymphocytes, macrophages) or granulocytes (eosinophils, mast cells and globule leucocytes). This cellular response was more pronounced in the ethmoid and sinus (development sites of second and third instar larvae) than in the septum or turbinates where first instar larvae migrate. Infected lambs produced Oestrus ovis specific IgG and IgA antibodies in their mucus. This local humoral response was mainly directed against larval salivary gland antigens and not against larval digestive tract antigens. Compared to the control animals, the sinusal mucosa of infected animals was extremely thickened and the epithelium exhibited hyperplasia, metaplasia and eosinophilic exocytosis. The possible roles of these local immune responses in the regulation of O. ovis larvae populations in sheep are discussed.  相似文献   

Immune modulation following immunization with polyvalent vaccines in dogs     

Strasser A  May B  Teltscher A  Wistrela E  Niedermüller H 《Veterinary immunology and immunopathology》2003,94(3-4):113-121

A decline in T-cell-mediated immunity and transient state of immunosuppression after immunization has been reported in dogs. Nevertheless, dogs are still routinely vaccinated with polyvalent live vaccines and severe disease does not generally occur. In order to investigate these effects on the canine immune system and to elucidate possible mechanisms we determined the following immune parameters in the blood of 33 clinically sound German shepherd dogs before and after standard vaccination with a polyvalent vaccine against distemper, parvovirus, viral hepatitis, leptospirosis, kennel cough and rabies: white and differential blood cell count, the serum concentrations and/or activities of IL-1, IL-2, IFN-gamma, TNF-alpha, neopterin and IgG, natural killer (NK) cell activity, bactericidal activity and complement hemolytic activity, lymphocyte proliferation test (LPT) and nitroblue tetrazolium test (NBT).Our major findings were that significant postvaccinal decreases in T-cell mitogenic response to PHA and in neutrophil function and neopterin serum concentration were accompanied by simultaneous increase in plasma IgG and hemolytic complement activity. This suggests a transient shift in the balance between cell-mediated and humoral (T(H)1/T(H)2) immunity rather than immunosuppression.These results do not imply that dogs should not receive live vaccines, as the response to vaccines just seems to create a state of altered homeostasis when immunization elicits protection by humoral and cell-mediated immunity. However, these recognized compromises of immune function should be considered and vaccines still be applied only in healthy animals and strictly according to the rules and regulations given by the manufacturer.  相似文献   

Change of porcine circovirus 2 target cells in pigs during development from fetal to early postnatal life   总被引：13，自引：0，他引：13  

Sanchez RE  Meerts P  Nauwynck HJ  Pensaert MB 《Veterinary microbiology》2003,95(1-2):15-25

Change of porcine circovirus 2 (PCV2) target cells during development from fetal to postnatal life in pigs was examined. PCV2 inoculation was performed in fetuses in utero at either 57, 75 or 92 gestational days and in piglets at 1 day of age. Twenty-one days after virus inoculation, PCV2-infected cells in the heart, lungs, liver, spleen and inguinal lymph nodes were localized and immuno-phenotyped by double-immunofluorescence labeling using different cell markers and PCV2-antibodies. During fetal life, viral antigens were detected in cardiomyocytes, hepatocytes and macrophages and infected cell numbers decreased with increasing fetal age at inoculation. The heart contained the highest number of infected cells and cardiomyocytes were the main target cell. Postnatally, macrophages were the only target cell type in different organs and infected cell numbers were similar to those of fetuses inoculated at 92 days of gestation. One piglet showed exceptionally high number of infected cells in different organs with values 13-513-fold higher compared to littermates. In this piglet, the majority of infected cells in lymphoid tissues could not be typed. This study reveals that PCV2 target cells change from cardiomyocytes, hepatocytes and macrophages during fetal life to only macrophages postnatally.  相似文献   

Disagrees with classification of a treatment for digital dermatitis     

Riemann HP 《Journal of the American Veterinary Medical Association》2002,220(2):167; author reply 167

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Antibody-induced internalization of viral glycoproteins in pseudorabies virus-infected monocytes and role of the cytoskeleton: a confocal study     

Van de Walle GR  Favoreel HW  Nauwynck HJ  Van Oostveldt P  Pensaert MB 《Veterinary microbiology》2002,86(1-2):51-57

Addition of pseudorabies virus (PrV)-specific polyclonal immunoglobulins to PrV-infected monocytes induces internalization of plasma membrane anchored viral glycoproteins. This process may interfere with antibody-dependent cell lysis and resembles the well-studied physiological endocytosis process. A confocal study was designed to investigate whether the major cellular components, involved in physiological endocytosis (clathrin, actin, dynein and microtubules), play a role in this virological internalization process. In order to visualize the interaction of endosomes, which contain the internalized viral glycoproteins, with clathrin, actin, dynein and microtubules, a double labeling of viral glycoproteins and different cellular proteins was performed. Porcine monocytes were inoculated with the PrV-strain 89V87 at a multiplicity of infection of 50 for 13h. After the addition of FITC-labeled porcine polyclonal PrV-specific antibodies, cells were fixed with para-formaldehyde at different time points and afterwards permeabilized. The different cellular components were visualized with monoclonal antibodies and a Texas Red-conjugate, with the exception of actin, which was stained with phalloidin-Texas Red. The cells were analyzed by confocal microscopy. A clear co-localization was observed between the viral glycoproteins and clathrin and dynein during the internalization process. The microtubules were in close contact with the internalized vesicles. For actin no co-localization could be observed. It can be stated that clathrin, dynein and microtubules, important components during physiological endocytosis, are also of importance during the antibody-induced internalization of viral glycoproteins.  相似文献   

Maximum-likelihood estimation of sensitivity and specificity of ELISAs and faecal culture for diagnosis of paratuberculosis     

Nielsen SS  Grønbaek C  Agger JF  Houe H 《Preventive veterinary medicine》2002,53(3):191-204

The accuracy of three diagnostic tests for paratuberculosis was evaluated using maximum-likelihood estimation of sensitivity and specificity. We also explored the variety of estimates that can be obtained if the tests are to be used in populations of different composition with regard to infection and disease states. Two enzyme-linked immunosorbent assays (ELISAs) were evaluated separately with the faecal culture (FC). The study was carried out as a cross-sectional field study to cover all likely states of infection with Mycobacterium avium subsp. paratuberculosis.The three basic assumptions for the maximum-likelihood technique were evaluated to validate the results. Our accuracy estimates for the ELISAs were not very different from those previously published, but those for faecal culture differed if a different cut-off value was chosen for the ELISA. If faecal culture was used for screening in a Danish dairy region where the median ELISA reading was a measure of the general disease situation, the sensitivity of the faecal culture was 20-25%. If faecal culture was used as a confirmatory test on cows with a high ELISA reading (and thus high level of antibodies), the sensitivity of the faecal culture would be in the range 60-70%. These results emphasise the importance of the composition of a target population before selecting a specific diagnostic test for a given purpose. We concluded that faecal culture is useful for confirmation but not for screening purposes.  相似文献   

Reference values for activated coagulation time in cats     

Bay JD  Scott MA  Hans JE 《American journal of veterinary research》2000,61(7):750-753

OBJECTIVE: To establish reference values for activated coagulation time (ACT) in cats by use of jugular venipuncture and direct collection of blood into ACT vacuum tubes. ANIMALS: 100 clinically normal cats that were to have elective surgery performed at a private practice. PROCEDURE: Collection of 3 blood samples for ACT measurement was attempted for each cat at the time of elective surgery: sample 1, obtained before sedation; sample 2, tube 1 of 2 consecutive samples obtained from a single venipuncture of the contralateral jugular vein after sedation with acepromazine and ketamine hydrochloride; and sample 3, tube 2 collected immediately following collection of sample 2 without removing the needle from the vein. Venipuncture quality was rated subjectively on a 3-point scale. RESULTS: Median ACT were 95 seconds for each sample group. The middle 95% of values ranged inclusively from 55 to 185 seconds (sample 1), 65 to 135 seconds (sample 2), 45 to 145 seconds (sample 3), and 55 to 165 seconds overall (samples 1, 2, and 3). Significant differences in ACT values were not detected between sample groups. Significant relationships between ACT and venipuncture quality or sex of cat were not detected. CONCLUSIONS AND CLINICAL RELEVANCE: With the ACT protocols used, clinically normal cats had ACT of < 165 seconds. The ACT in cats does not appear to be significantly affected by sex, sedation with acepromazine and ketamine, or by moderately traumatic venipunctures. These results refute widespread statements that ACT should be < 65 seconds in healthy cats. Cats with ACT repeatedly > 165 seconds should be further evaluated for hemostatic disorders.  相似文献   

Identification of pathogenic Leptospira strains in tissues of a premature foal by use of polymerase chain reaction analysis.     

Albertine Léon  Stéphane Pronost  Jackie Tapprest  Nathalie Foucher  Béatrice Blanchard  Geneviève André-Fontaine  Claire Laugier  Guillaume Fortier  Roland Leclercq 《Journal of veterinary diagnostic investigation》2006,18(2):218-221

Studies were carried out to determine the cause of death in a prematurely born Thoroughbred foal that died 24 hours after birth. Necropsy revealed gross lesions suggestive of septicemia. A commercial Leptospira polymerase chain reaction (PCR) assay designed to specifically amplify the hemolysis-associated protein 1 (hap1) gene present only in pathogenic Leptospira strains detected the presence of Leptospira DNA in various tissues of the foal. Histologic examination of lung, liver, kidney, and myocardium revealed numerous spirochetes in Warthin-Starry-stained tissue sections. Results of PCR analysis and histologic examination suggested a leptospiral infection in the newborn foal. At the moment of death, the infection coexisted with a streptococcal-associated aspiration bronchopneumonia and postpartum septicemia. These findings indicate that the PCR assay based on the amplification of the hap1 gene represents a useful tool for specific detection of pathogenic leptospira in field samples taken from horses.  相似文献   

Some Mechanisms Involved in the Response of Mares to Photoperiodic Stimulation of Reproductive Activity     

E Palmer  D Guillaume 《Reproduction in domestic animals》1998,33(3-4):205-208

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Erratum to: Physiological and behavioral responses to an electrical stimulus in Mozambique tilapia (Oreochromis mossambicus)     

Jonathan A. C. Roques  Wout Abbink  Gaétan Chereau  Aurélie Fourneyron  Tom Spanings  Dirk Burggraaf  Ruud van den Bos  Hans van de Vis  Gert Flik 《Fish physiology and biochemistry》2012,38(6):1855-1855

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