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121.
Cats were vaccinated with one of the three preparations: purified feline immunodeficiency virus (FIV) incorporated into immune stimulating complexes (ISCOMs), recombinant FIV p24 ISCOMs, or a fixed, inactivated cell vaccine in quil A. Cats inoculated with the FIV ISCOMs or the recombinant p24 ISCOMs developed high titres of antibodies against the core protein p24 but had no detectable antibodies against the env protein gp120 or virus neutralising antibodies. In contrast, all of the cats inoculated with the fixed, inactivated cell vaccine developed anti-env antibodies and four of five had detectable levels of neutralising antibody. However, none of the vaccinated cats were protected from infection after intraperitoneal challenge with 20 infectious units of FIV. Indeed there appeared to be enhancement of infection after vaccination as the vaccinated cats become viraemic sooner than the unvaccinated controls, and 100% of the vaccinated cats became viraemic compared with 78% of the controls. The mechanism responsible for this enhancement remains unknown.  相似文献   
122.
123.
A reliable method for the collection of peritoneal fluid from cattle using a trocar and cannula is described. Peritoneal fluid was collected from three groups of cattle: periparturient, normal and with peritonitis. The fluid was examined by white cell count, differential cell count, total protein concentration and bacteriology. The results were analysed to determine the best criteria for peritonitis. Greater than 10% eosinophils were typical of normal peritoneal fluid. Peritoneal fluid with a relative neutrophil count greater than 40% and a relative eosinophil count of less than 10% was frequently associated with the diagnosis of peritonitis. Parturient cattle had large volumes of peritoneal fluid with low total protein and white cell counts. Growth of Gram-negative or anaerobic organisms was associated with mortality.  相似文献   
124.
In an age of advancing endoscopic and lithotripsy technologies, the management of urolithiasis poses a unique opportunity to advance compassionate veterinary care, not only for patients with urolithiasis but for those with other urinary diseases as well. The following are consensus‐derived, research and experience‐supported, patient‐centered recommendations for the treatment and prevention of uroliths in dogs and cats utilizing contemporary strategies. Ultimately, we hope that these recommendations will serve as a foundation for ongoing and future clinical research and inspiration for innovative problem solving.  相似文献   
125.
126.
Fifty-two joints from pigs with nonsuppurative joint disease from a local abattoir were examined grossly, histologically, and microbiologically in order to establish macroscopic differences between degenerative arthropathy and arthritis due to an infectious organism. The joints were grouped grossly according to the type and severity of lesions of the synovial membrane and cartilage, and microscopically according to the severity of synovial membrane lesions. Osteochondrosis and Erysipelothrix rhusiopathiae were the most common causes of nonsuppurative joint disease in the joints examined. The major macroscopic differences between these two arthropathies were in the nature and severity of the synovial and cartilaginous lesions and involvement of the lymph node draining the diseased joint. Typically, in osteochondrosis, the changes are feathery hypertrophy of villi, focal full-thickness cartilage buckles, ulcers or flaps, and no change in the draining lymph node, whereas in Erysipelothrix- caused arthritis, the villous hypertrophy is severe and polypoid in nature, there is diffuse erosion of articular cartilage, and the draining lymph node is consistently hypertrophic and often cystic.  相似文献   
127.
Haemophilus somnus Mastitis in a Dairy Cow   总被引:3,自引:3,他引:0       下载免费PDF全文
A clinical case of peracute bovine mastitis is described in which the most severely affected quarter yielded a heavy growth of Haemophilus somnus on culture.  相似文献   
128.
Silica "jack-stone" uroliths developed in the urinary bladder and urethra of 83 dogs living in the United States. Naturally occurring silica jack stones have not been encountered prior to 1976. German Shepherd Dogs comprised more than 1/3 of affected animals; the remainder encompassed 26 other breeds. In this series, 81 were males and 2 were females. The mean age of the dogs was 5.8 years, with a range of 1.5 to 12 years. Several observations prompt the hypothesis that development of silica uroliths may be related to diet. Although most silica uroliths had a characteristic jack-stone appearance, not all silica uroliths had a jack-stone configuration and not all jack stones were composed of silica. Some calculi were comprised of a combination of silica and struvite. Silica uroliths were radiodense, compared with adjacent tissue, but were not associated with identifiable crystals in urine. The urine pH of affected dogs varied from acid to alkaline. Silica urolithiasis recurred in 5 dogs following surgery. Urinary tract infections, when they occurred, appeared to be a sequela of silica urolithiasis. Pending further studies, management of silica uroliths should include their removal from the urinary tract and eradication of associated urinary tract infections. Prophylactic measures should include attempts to augment urine volume and change of diet.  相似文献   
129.
The objectives of this study were: (1) to examine how foliar carbon isotope discrimination (Delta) and oxygen isotope composition (delta(18)O) are related to tree growth, ash mineral nutrient concentration and foliar nutrient concentration in 7-year-old clones of the F(1) hybrid between slash pine (Pinus elliottii Engelm.) and Caribbean pine (P. caribaea var. hondurensis Barr. et Golf.) in subtropical Australia; and (2) to evaluate the potential of using foliar Delta, ash mineral nutrient concentration and delta(18)O measurements for selecting F(1) hybrid pine clones with high water-use efficiency (WUE) and growth potential. There were significant differences in tree growth, foliar Delta, delta(18)O and ash mineral nutrient concentration among the eight clones tested. Significant negative linear relationships existed between tree growth and Delta, extrapolating to zero growth at Delta = 24-30 per thousand. There were strong genetic correlations (r = -0.83 to -0.96) between Delta and tree growth, particularly tree height. Significant non-genetic correlations (r = -0.62 to -0.80) existed between Delta and foliar K concentration. Foliar delta(18)O, ash mineral nutrient concentration and foliar nutrient concentration were unrelated to tree growth. In the F(1) hybrid pine clones, variation in tree WUE, as reflected by Delta, was largely attributed to a genetic effect on leaf photosynthetic capacity rather than on stomatal conductance, as reflected by foliar delta(18)O.  相似文献   
130.
ABSTRACT Analyses of multiple field experiments indicated that the incidence and relative abundance of root-colonizing phlD+ Pseudomonas spp. were influenced by crop rotation, tillage, organic amendments, and chemical seed treatments in subtle but reproducible ways. In no-till corn plots, 2-year rotations with soybean resulted in plants with approximately twofold fewer phlD+ pseudomonads per gram of root, but 3-year rotations with oat and hay led to population increases of the same magnitude. Interestingly, tillage inverted these observed effects of cropping sequence in two consecutive growing seasons, indicating a complex but reproducible interaction between rotation and tillage on the rhizosphere abundance of 2,4-diacetlyphloroglucinol (DAPG) producers. Amending conventionally managed sweet corn plots with dairy manure compost improved plant health and also increased the incidence of root colonization when compared with nonamended plots. Soil pH was negatively correlated to rhizosphere abundance of phlD+ pseudomonads in no-till and nonamended soils, with the exception of the continuous corn treatments. Chemical seed treatments intended to control fungal pathogens and insect pests on corn also led to more abundant populations of phlD in different tilled soils. However, increased root disease severity generally was associated with elevated levels of root colonization by phlD+ pseudomonads in no-till plots. Interestingly, within a cropping sequence treatment, correlations between the relative abundance of phlD and crop stand or yield were generally positive on corn, and the strength of those correlations was greater in plots experiencing more root disease pressure. In contrast, such correlations were generally negative in soybean, a difference that may be partially explained by difference in application of N fertilizers and soil pH. Our findings indicate that farming practices can alter the relative abundance and incidence of phlD+ pseudomonads in the rhizosphere and that practices that reduce root disease severity (i.e., rotation, tillage, and chemical seed treatment) are not universally linked to increased root colonization by DAPG-producers.  相似文献   
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