Fusarial toxins: are they a cause for concern?     

Moss MO 《Veterinary journal (London, England : 1997)》2003,165(3):184-185

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Increased susceptibility of peripheral blood mononuclear cells to equine herpes virus type 1 infection upon mitogen stimulation: a role of the cell cycle and of cell-to-cell transmission of the virus     

van der Meulen KM  Nauwynck HJ  Pensaert MB 《Veterinary microbiology》2002,86(1-2):157-163

Equine herpesvirus-1 (EHV-1) is an important pathogen of horses, causing abortion and nervous system disorders, even in vaccinated animals. During the cell-associated viremia, EHV-1 is carried by peripheral blood mononuclear cells (PBMC), mainly lymphocytes. In vitro, monocytes are the most important fraction of PBMC in which EHV-1 replicates, however, mitogen stimulation prior to EHV-1 infection increases the percentage of infected lymphocytes. The role of the cell cycle in viral replication and the role of cluster formation in cell-to-cell transmission of the virus were examined in mitogen-stimulated PBMC. Involvement of the cell cycle was examined by stimulating PBMC with ionomycin/phorbol dibutyrate (IONO/PDB) during 0, 12, 24 and 36 h prior to inoculation. Cell cycle distribution at the moment of inoculation and the percentage of EHV-1 antigen-positive PBMC at 0, 12 and 24 hours post inoculation (hpi) were determined by flow cytometry and immunofluorescence microscopy, respectively. The role of clusters was examined by immunofluorescence staining within clusters of stimulated PBMC using antibodies against EHV-1. Significant correlations were found between the increase of cells in the S- or G2/M-phase after a certain time interval of prestimulation and the increase of EHV-1 antigen-positive cells. The percentage of clusters with adjacent infected cells significantly increased from 3.3% at 8 hpi to 23.7% at 24 hpi and the maximal number of adjacent infected cells increased from 2 to 7. Addition of anti-EHV-1 hyperimmune serum did not significantly alter these percentages. Mitogen stimulation favours EHV-1 infection in PBMC by: (i) initiating cell proliferation and (ii) inducing formation of clusters, thereby facilitating direct cell-associated transmission of virus.  相似文献   

Factors affecting ascorbic acid (AsA) biosynthesis in chickens. II. Effect of dietary AsA and strain of chicken     

Hooper CL  Maurice DV  Lightsey SF  Toler JE 《Journal of animal physiology and animal nutrition》2002,86(9-10):326-332

The present study examined the effect of supplemental ascorbic acid (AsA) and ascertained if genotype is a determinant of biosynthesis and the response of strains to dietary AsA. Slow- (Ottawa Meat Control; OMC) and fast-growing (Peterson Enhanced x Hubbard; PEH) chicks were fed 1000 mg/kg AsA from 1 to 10 weeks of age. The activity of l-gulonolactone oxidase (GLO) was used to measure biosynthesis and estimated synthetic capacity (ESC) computed. Body weight was not affected by diets and relative kidney weight decreased with age. In 1 week, dietary AsA increased plasma AsA and inhibited GLO activity with a greater reduction in OMC birds. At 10 weeks, GLO activity was depressed almost uniformly in both strains. Strain by age and diet by age interactions were detected for GLO activity and ESC with significantly greater decline in PEH birds and birds fed supplemental AsA. The results demonstrated that dietary AsA inhibited biosynthesis in meat type chickens and the response at 10 weeks was not influenced by growth rate; and the age dependent decline in biosynthesis was more pronounced in the commercial PEH birds. The result suggests that such strains may be compromised in some situations. Research using multiple dietary levels of AsA, commercial strains, and defined stressors is warranted.  相似文献   

Factors affecting ascorbic acid biosynthesis in chickens: III. Effect of dietary fluoride on L-gulonolactone oxidase activity and tissue ascorbic acid (AsA) concentration     

Maurice DV  Lightsey SF  Abudabos A  Toler JE 《Journal of animal physiology and animal nutrition》2002,86(11-12):383-388

The inconsistent beneficial responses to dietary ascorbic acid (AsA) may be due to dietary factors that alter biosynthesis or tissue turnover of AsA. It has been suggested on the basis of altered tissue AsA that dietary fluoride is a determinant of biosynthesis in chickens. Fluoride may enter the food chain of poultry via industrial contamination, feed ingredients and drinking water. The goal of this study was to ascertain whether dietary fluoride at 300 mg/kg influences l-gulonolactone oxidase (GLO) activity in commercial meat-type chickens. The experimental diet was fed from day-old to 3 weeks and responses measured. Growth and feed conversion were not affected by fluoride in the diet. Dietary fluoride neither inhibited nor enhanced GLO activity nor did it increase or decrease AsA concentration in plasma, liver, kidney, adrenal gland and muscle (pectoralis major). Tissue AsA concentration in ascending order was adrenal > liver > kidney > pectoralis major > plasma. The results are consistent with that reported for the rat and calculations based on the results eliminate fluorine contamination for the inconsistent responses of immature chickens to dietary AsA.  相似文献   

Rinderpest vaccination trial of calves passively immune due to colostrum antibodies with an inactivated adjuvated vaccine prepared in cell cultures     

A Provost  C Borredon  Y Maurice 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1969,22(4):473-479

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Le Lait, Son Inspection Et Le Medecin-Veterinaire          下载免费PDF全文

Maurice Mercure 《Canadian journal of veterinary research》1954,18(8):294-301

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Possibilities and limits of the measles hemagglutination inhibition inhibition test in the serology of rinderpest. 3. Use of blotting paper in the serology of rinderpest involving MHI test     

Y Maurice  A Provost 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1969,22(1):17-23

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Possibilities and limits of the measles hemagglutination inhibition test in the serology of rinderpest. II. Dissimilarity between the results obtained with this test and the rinderpest virus seroneutralization     

A Provost  Y Maurice  C Borredon 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1969,22(1):9-15

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Studies of the adsorption of paraquat on soluble humic fractions by gel filtration and ultrafiltration techniques     

Ian G. Burns  Michael H. B. Hayes  Maurice Stacey 《Pest management science》1973,4(5):629-641

The adsorption of paraquat dichloride (1,1′-dimethyl-4,4′-bipyridylium dichloride) on a soluble sodium humate fraction of a Fenland soil was studied by gel filtration (on Sephadex G10 and G100) and by ultrafiltration (through an Amicon Diaflo UM-2 ultrafilter). Both methods depend upon the separation, on a molecular weight basis, of the unadsorbed molecules of herbicide from the adsorption complex (consisting of polymeric organic materials and the adsorbed paraquat). Separations were obtained on columns of Sephadex G10 (Method I) and in the ultrafiltration experiments (Method II), and isotherms were prepared from data for adsorption in water (by Method II) and in sodium chloride (by Methods I and II) solutions. Results from the two methods were comparable over the concentration range examined. The increased adsorption of paraquat by Na⁺-compared with Ca²⁺-humate is explained on the basis of the selectivity sequence of humate for exchangeable cations. Attempts to prepare isotherms from gel filtration data, for the adsorption of paraquat on two soluble model humic polymers (polyacrylic acid and a polymer prepared by the oxidative coupling of benzoquinone and ammonium chloride) were unsuccessful because binding to the gel matrix did not permit quantitative recoveries of the adsorption complexes. Paraquat was adsorbed to the same extent on each of four fractions of Na⁺-humate separated on Sephadex G100.  相似文献   

Horse sickness caused by type 9 virus in Central Africa: serological survey     

Y Maurice  A Provost 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1967,20(1):21-25

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