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31.
Eastern equine encephalitis (EEE) was diagnosed (postmortem) in a sheep with clinical signs attributable to a central nervous system disease. The sheep was febrile and initially had front limb incoordination, which progressed to paralysis of both front and hind limbs during a course of 2 days. The sheep maintained an alert attitude with the ability to eat up to the time of euthanasia. The only clinical pathologic abnormalities were neutrophilia and lymphopenia without appreciable leukocytosis, a moderate hyperglycemia, and an elevated creatine kinase. Treatment included hydrotherapy for lowering body temperature, intravenous fluids, thiamine hydrochloride, tetanus antitoxin, antibiotics, and corticosteroids. The only gross lesion at the time of necropsy was a wet glistening surface of the brain (leptomeninges). Microscopically, there was severe nonsuppurative meningoencephalitis, poliomyelitis, and polyradiculoneuritis with mild multifocal neutrophilic infiltration. The EEE virus was isolated from the brain, and subsequent fluorescent antibody testing for EEE was positive on cell culture.  相似文献   
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The insecticidal activities of materials derived from the fruit of fennel, Foeniculum vulgare, against adults of Sitophilus oryzae, Callosobruchus chinensis and Lasioderma serricorne were examined using direct contact application and fumigation methods. The biologically active constituents of the Foeniculum fruits were characterized as the phenylpropenes (E)‐anethole and estragole, and the monoterpene (+)‐fenchone, by spectroscopic analysis. Responses varied with insect species, compound, dose and exposure time. In a filter paper diffusion test, estragole at 0.168 mg cm?2 caused 91% mortality to S oryzae adults within 1 day after treatment (DAT), whereas (+)‐fenchone and (E)‐anethole gave over 90% mortality at 2 and 4 DAT, respectively. Against C chinensis adults, all test compounds revealed potent insecticidal activities at 0.021 mg cm?2 at 2 DAT. Against L serricorne adults at 0.105 mg cm?2, (E)‐anethole gave 100% mortality at 1 DAT, whereas 90 and 60% mortality at 4 DAT was achieved with estragole and (+)‐fenchone, respectively. In a fumigation test, the test compounds were much more effective against adults of S oryzae, C chinensis and L serricorne in closed cups than in open ones, indicating that the insecticidal activity of test compounds was largely attributable to fumigant action. As naturally occurring insect‐control agents, the F vulgare fruit‐derived materials described could be useful for managing field populations of S oryzae, C chinensis and L serricorne. © 2001 Society of Chemical Industry  相似文献   
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OBJECTIVE: To enumerate the prevalence of Campylobacter isolates in the intestinal tract of market-weight swine raised in an integrated swine operation in Texas. SAMPLE POPULATION: Samples of cecal contents were collected from 595 pigs (mean body weight, 110 kg [242 lb]) at time of slaughter. Pigs were off-spring of Yorkshire-Landrace sows and Duroc or Hampshire boars. Pigs originated from 4 farrow-to-finish farms. PROCEDURE: During a 9-month period, visits were made to a slaughter plant to remove cecal contents from market-weight hogs. Samples were obtained from 50 pigs/visit from designated farms so that samples were obtained 3 times from pigs of each of 4 farms. Isolation of Campylobacter spp was accomplished by use of enrichment broth and restrictive media, using microaerophilic conditions. RESULTS: Campylobacter spp were isolated from 70 to 100% of the pigs, depending on the farm and the date the samples were collected. Campylobacter coli was isolated from 20 to 100% (mean, 60%) of samples, and C jejuni was isolated from 0 to 76% (mean, 31%) of samples. Campylobacter lari was isolated from 2 pigs. Concentrations of C coli or C jejuni ranged from 10(3) to 10(7) colony-forming units/g of cecal content. CONCLUSIONS AND CLINICAL RELEVANCE: Campylobacter coli generally is accepted as a common inhabitant of the intestinal tract of swine. However, analysis of results of this study suggests that a relatively high prevalence of C jejuni may be found in pigs raised on specific farms.  相似文献   
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OBJECTIVE: To determine the diagnostic value of aerobic microbial culture and cytologic evaluation of corneal specimens in the diagnosis of infectious ulcerative keratitis (IUK). DESIGN: Prospective study. ANIMALS: 48 animals (26 dogs, 13 horses, 7 cats, 1 bird, and 1 llama) with corneal ulcers. PROCEDURE: Scrapings from corneal ulcers were examined cytologically. Corneal swab specimens were submitted for microbial culture. Animals were grouped according to whether they had been receiving antimicrobials at the time of admission. RESULTS: Of the 38 animals receiving antimicrobials, 19 had positive results for IUK on cytologic evaluation, 20 on microbial culture, and 26 on cytologic evaluation, microbial culture, or both. Of the 10 animals not receiving antimicrobials at the time of admission, 7 had positive results for IUK on cytologic evaluation, and 9 had positive results on microbial culture. In this group of 10 animals, additional animals with IUK were not identified on the basis of cytologic evaluation alone. When all 48 animals were considered irrespective of antimicrobial treatment, 26 and 29 had positive results for IUK on cytologic evaluation and microbial culture, respectively, whereas IUK was confirmed in 35 animals on the basis of cytologic evaluation, microbial culture results, or both. CONCLUSIONS AND CLINICAL RELEVANCE: Microbial culture and cytologic evaluation of corneal specimens maximizes identification of IUK, especially in animals receiving antimicrobial treatment. Because of serious consequences of untreated IUK, we recommend that both diagnostic tests be used to tailor treatment and reduce risk of vision impairment in animals.  相似文献   
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This study was conducted to determine whether an antimicrobially induced (ASP-250) increase in serum IGF-I was the result of differences in feed intake. Serum IGF-I concentrations were measured in crossbred pigs that were fed a control diet or a diet supplemented with ASP-250 either for ad libitum consumption or limited to 85% of the control pigs' consumption. The pigs that consumed either diet ad libitum, control or ASP-250, consumed similar quantities of feed. The ASP-250 ad libitum-intake pigs had serum IGF-I concentrations that were greater (P<.01) than those of their ad libitum-intake control littermates. Similarly, the ASP-250 limit-fed pigs had serum IGF-I concentrations that were greater (P<.01) than those of the controls. Although the serum IGF-I concentrations of pigs fed the ASP-250-supplemented diet for ad libitum intake were greater than the serum IGF-I concentrations of the pigs limit-fed the ASP-250-supplemented diet, the differences were not significant (P<.08). The ASP-250-fed pigs had higher serum IGF binding protein (BP)-3 concentrations than did their control littermates (P<.003). A time course of antimicrobially induced alterations in serum IGF-I concentrations revealed that the effect of increased serum IGF-I levels in ASP-250-supplemented pigs (P<.02) was observed within 4 d and was maintained throughout the 4-wk study. These findings show that feed intake is not responsible for the increase in serum IGF-I observed with ASP-250 supplementation. Additionally, the antimicrobially induced increase in serum IGF-I concentrations occurs within a few days after initiation of the treatment.  相似文献   
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Eighteen barrows approximately three weeks of age were used in a 3 X 3 factorial arrangement to investigate the effect of level of supplemental vitamin E and selenium on tissue and blood parameters. Tissue selenium concentrations increased in a quadratic manner with increased selenium intake with kidney tissue containing considerably greater concentrations than liver, heart or muscle. Supplementation of the diet caused a three-fold increase in serum selenium within the first week with a slight tendency to further increases in subsequent weeks. Serum vitamin E of unsupplemented pigs declined by fifty percent during the experiment, whereas supplemental vitamin E resulted in increased serum vitamin E. There was a considerable viration in percent peroxide hemolysis. Correlation of -0.63 between percent peroxide hemolysis and vitamin E intake and -0.85 between percent peroxide hemolysis and serum vitamin E were observed.  相似文献   
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