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1.
Immunogenicity of Brucella abortus salt-extractable proteins 总被引:5,自引:0,他引:5
The immunogenic properties of salt-extractable proteins and chromatographic fractions thereof from Brucella abortus were evaluated in lemmings (Dicrostonyx rubricatus). The efficacy of the Brucella proteins as immunogens was determined after challenge with virulent B. abortus strain 2308 and was based on protection against clinical signs and gross lesions of brucellosis, as well as on numbers of viable Brucella in the spleen. Vaccination of lemmings with as little as 0.1 microgram of salt-extractable proteins (CSP) suppressed splenic infection, resulting in reduced numbers of viable organisms per spleen of 5-6 logs compared to non-vaccinated controls. Protein fractions separated by column chromatography were generally effective in reducing splenic infection, and contained proteins with molecular weights of 30,000, 20,000 and 12,000. Vaccines containing chemically modified dodecanoyl-CSP offered no additional advantage over unmodified CSP vaccines. 相似文献
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M E Haskins P F Jezyk R J Desnick S K McDonough D F Patterson 《Journal of the American Veterinary Medical Association》1979,175(4):384-387
A 10-month-old male domestic short-haired cat was examined because of progressive lameness, a broad face with depressed nasal bridge, small ears, corneal clouding, and multiple bone dysplasia. The cat excreted excessive amounts of glycosaminoglycan (a component of connective tissue) in its urine and had evidence of lysosomal storage of glycosaminoglycans in fibroblasts and neurons. Activity of alpha-L-iduronidase, a lysosomal enzyme involved in glycosaminoglycan degradation, was deficient in cultured fibroblasts and leukocytes. The mucopolysaccharidosis was distinct from that seen in Siamese cats in terms of the pathologic changes and the specific enzyme deficiency. 相似文献
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Serums from infected cattle, cattle with persistent postvaccinal antibody, and serologically "positive" noninfected cattle were fractionated into major immunoglobulin classes by diethylaminoethyl (DEAE)-cellulose chromatography and by sucrose density gradient centrifugation. Each fraction was assayed for anti-Brucella activity by standard tube-agglutination test (STT), buffered tube-agglutination test (BTT), and complement-fixation test (CF). In the serums from experimentally infected cattle, anti-Brucella antibody could be found by all tests in 6 DEAE fractions and in slow, fast, and sediment regions of the density gradient. Serums from cattle with persistent postvaccinal titers had STT activity in all 6 DEAE fractions, BTT activity in 5 fractions, and CF activity in only 1 fraction. The STT and BTT activities were found in the slow and the sediment regions of the gradient, whereas the CF activity was found only in the slow region. Serums from a chronically infected animal had STT and BTT activities in 2 DEAE fractions and CF activity in only 1. The STT, BTT, and CF activities were found in the slow and the sediment regions of the gradient. The principal antibody in serums from noninfected cattle was immunoglobulin M, which had all of the CF activity and most of the STT and BTT activities. Low levels of STT and BTT activities were found in 3 other DEAE fractions. Only STT and BTT activities were found in the fast and the sediment regions of the gradient. 相似文献
5.
M. Podell H.A. Volk M. Berendt W. Löscher K. Muñana E.E. Patterson S.R. Platt 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2016,30(2):477-490
This report represents a scientific and working clinical consensus statement on seizure management in dogs based on current literature and clinical expertise. The goal was to establish guidelines for a predetermined, concise, and logical sequential approach to chronic seizure management starting with seizure identification and diagnosis (not included in this report), reviewing decision‐making, treatment strategies, focusing on issues related to chronic antiepileptic drug treatment response and monitoring, and guidelines to enhance patient response and quality of life. Ultimately, we hope to provide a foundation for ongoing and future clinical epilepsy research in veterinary medicine. 相似文献
6.
Friedman DB Kanwat CP Headrick ML Patterson NJ Neely JC Smith LU 《Zoonoses and public health》2007,54(9-10):366-375
Inappropriate use of antibiotics in humans and animals contributes to decreased antimicrobial susceptibility in bacteria of medical importance. Resistant bacteria being transferred from animals to humans are causing public health concern. In-person interviews were conducted with 20 dairy farmers in rural counties of South Carolina to determine farmers' knowledge and attitudes about prudent antibiotic use among livestock. Four focus groups (n = 22) were also conducted to ascertain farmers' specific information needs about proper antibiotic use. Survey results showed that participants (100%) typically determined a need for antibiotic treatment using symptom assessment and reported following some form of operating procedures regarding administration of antibiotics. Few farmers (32%) had actual written antibiotic protocols. Preferred information sources about antibiotics were veterinarians (100%) and other dairy farmers (50%). Most farmers (86%) were not concerned that overuse of antibiotics in animals could result in antibiotic resistance among farm workers. Qualitative analysis of focus groups revealed significant barriers to following proper antibiotic procedures including limited finances and lack of time. The need for bilingual educational resources for Hispanic/Latino dairy workers was expressed. Desired formats for educational materials were posters, flowcharts, videos, and seminars. Education of South Carolina dairy farmers by veterinarians and public health professionals on the appropriate use of antibiotics in dairy cattle is needed to ensure antibiotic effectiveness in both animals and humans. 相似文献
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Detection of twelve mycotoxins in mixed animal feedstuffs, using a novel membrane cleanup procedure.
B A Roberts D S Patterson 《Journal of the Association of Official Analytical Chemists》1975,58(6):1178-1181
A multimycotoxin thin layer chromatographic screening method is described which is applicable to most animal feedstuffs. Interference from nonspecific lipid, pigment, and other components of simple and mixed feeds is reduced to a minimum by using a membrane cleanup step. Aflatoxins B1, B2, G1, and G2, citrinin, diacetoxyscirpenol, ochratoxin A, patulin, penitrem A, sterigmatocystin, T-2 toxin, and zearalenone may be reliably detected. The sensitivity of the method is generally low for mixed feeds but even so aflatoxin B1 can be detected at a level of 3 ppb and ochratoxin A at 80 ppb. While the basic method is less sensitive for sterigmatocystin (330 ppb), patulin (600 ppb), zearalenone (1000 ppb), and the trichothecenes (1000-4000 ppb), it may be adapted so as to reduce the above detection limits when the presence of these toxins is suspected. Lower levels may be detected in extracts of simple feeds. 相似文献
10.
Abstract – The persistent effects of embryonic temperature stress and individual parentage on fry swimming performance were examined in a cross‐fertilisation experiment using sockeye salmon (Oncorhynchus nerka). A fixed‐velocity test of burst swimming was used to assess the endurance capacity and behavioural performance of individual fry from 10 offspring families incubated at 12, 14 or 16 °C to hatch and then reared through yolk absorption and exogenous feeding stages in a common posthatch environment (average 6.9 °C). Fry burst swim time (BST) was influenced by an interaction between incubation temperature and family identity. Average BST was longer for fry from the 12 °C prehatch treatment compared to 14 and 16 °C, although differences were largely attributable to temperature effects on average fry size. Behavioural observations revealed that fish incubated at 16 °C performed more poorly, having a larger proportion of individuals that required stimulation to swim, fatigued more frequently or were classified as ‘nonswimmers’. Within all three incubation temperature treatments, mean BST varied significantly among offspring families, independent of fry mass and length. An interesting relationship was observed within the 16 °C treatment, whereby families with higher survivorship were characterised with lower mean BSTs. Collectively, these findings demonstrate that exposure to high temperatures in early sockeye salmon development can result in persistent, parentally mediated effects on fry performance. As such, these results provide important insight into how elevated temperature events during egg incubation may affect early life history selection processes and survival in stages beyond when the stressor is experienced. 相似文献