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941.
942.
Effects of the fungal endophyte Acremonium coenophialum in fescue on pregnant mares and foal viability. 总被引:1,自引:0,他引:1
M R Putnam D I Bransby J Schumacher T R Boosinger L Bush R A Shelby J T Vaughan D Ball J P Brendemuehl 《American journal of veterinary research》1991,52(12):2071-2074
Effects of the endophyte Acremonium coenophialum in tall fescue on pregnant mares and foal viability were evaluated. Twenty-two mature pregnant mares were randomly chosen to graze either Kentucky-31 tall fescue that was free from A coenophialum (endophyte-free, EF) or tall fescue infected with A coenophialum (endophyte-present, EP) after the first 90 days of pregnancy through parturition. Concentrations of pyrrolizidine and ergopeptine alkaloids were significantly greater in EP grass, compared with EF pasture. Ten of 11 mares grazing EP pasture had obvious dystocia. Mean duration of gestation was significantly greater for the EP group, compared with the EF group. Foal survivability was severely reduced among mares grazing EP fescue with only 1 foal surviving the natal period. Udder development and lactation were low in mares grazing EP grass. The absence of clinical problems in mares grazing EF grass implicated the endophyte as the causative agent of reproductive problems and perinatal foal mortality in pregnant mares grazing endophyte-infected fescue grass. Caution should be exercised in allowing pregnant mares to graze pastures infected with the endophyte A coenophialum. 相似文献
943.
Salmonid immunoglobulin purification has been hampered by time-consuming, labour-intensive, conventional chromatographic procedures. In this report we describe the use of immunoaffinity chromatography for the purification of immunoglobulins from trout serum in a single step. An anti-heavy chain monoclonal antibody (1G7) which reacts with more than 85% of total trout immunoglobulins was used to purify the trout immunoglobulin. The purity achieved was higher than 95%, and the immunoglobulins recovered were fully immunogenic. This method served equally well in isolating immunoglobulins from the sera of other salmonids (coho salmon and chinook salmon). The procedure should be useful in the standardization of salmonid immunoglobulin reagents. 相似文献
944.
945.
946.
Lack of pathogenicity of haemophili of the 'minor group' taxon for the gnotobiotic piglet 总被引:1,自引:0,他引:1
After intranasal instillation two freshly isolated English strains of Haemophilus taxon 'minor group' produced persistent infection in the tonsil but failed to elicit macroscopic or histological changes in the lower respiratory tract of two pairs of 14-day-old gnotobiotic piglets whereas a freshly isolated English strain of Haemophilus pleuropneumoniae caused a lethal pleuropneumonia in a third pair. 相似文献
947.
948.
I. B. Griffiths D. G. Parra O. G. Vizcaino M. I. Gallego 《Tropical animal health and production》1986,18(3):155-157
Summary When 1, 711 bovine faecal samples from 113 farms in eight dairy areas of Colombia were examined for the presence of helminth
eggsFasciola hepatica eggs were found in the faeces from 60% of the farms and samples from animals kept above 2,000 m. Strongyle eggs were found
in faeces from 82% of the farms and in 18% of the samples.
Resumen Se examinaron 1.711 muestras fecales provenientes de 113 fincas, localizadas en ocho zonas lecheras de Colombia. Se encontraron huevos deFasciola hapatica, en el 60% de fincas y muestras fecales de animales sobre los 2,000 m.s.n.m. Se encontraron tambien huevos de estrogilideos en heces del 82% de fincas y en el 18% de las muestras examinadas.
Résumé La recherche d’oeufs d’helminthes sur 1711 échantillons de fécès provenant de 113 fermes de 8 districts laitiers de Colombie a permis de noter la présence d’oeufs deFasciola hepatica dans 60 p. 100 des fermes et échantillons originaires d’animaux vivant à plus de 2,000 m. Des oeufs de strongles ont été notés dans les fécès provenant de 82 p. 100 des fermes et 18 p. 100 des échantillons.相似文献
949.
S I Reinke P J Ihrke J D Reinke A A Stannard S S Jang D M Gillette K W Hallock 《Journal of the American Veterinary Medical Association》1986,189(4):446-448
Actinomycotic mycetoma, a chronic, progressive infection of the subcutaneous tissue characterized by tumefaction, draining sinuses, and grains, was diagnosed in the right hindlimb of a young adult, male cat. The organisms that cause actinomycetoma are soil or plant saprophytes that gain entrance to the skin through abrasion or traumatic implantation. Streptomyces griseus, an organism generally considered to be a saprophyte, was cultured bacteriologically. Despite extensive surgery and long-term antibiotic therapy, the infection persisted, and the cat was euthanatized. 相似文献
950.
Thirty-five Pasteurella haemolytica strains were isolated in Hungary from goat carcasses sent for postmortem examination from two farms with large goat flocks. All strains belonged to biotype A and with the exception of one strain of serotype A8 they belonged to serotype A2. No untypable strains were found by the indirect haemagglutination test. 相似文献