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排序方式: 共有337条查询结果,搜索用时 15 毫秒
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Tatjana Lazic Mark R Ackermann Jo M Drahos Judith Stasko Joseph S Haynes 《Journal of veterinary diagnostic investigation》2008,20(2):235-238
A flock of Indian Ringneck parakeets (Psittacula krameri manillensis) was imported to the United States from Australia. Soon after, 1 parakeet suddenly died, and a second parakeet died after a 2-day course of illness, which consisted of anorexia, lethargy, emaciation, and dyspnea. At necropsy, the affected birds had diffuse consolidation and red discoloration of the lungs, as well as thickened, congested air sacs. The microscopic examination revealed multifocal, necrotizing bronchitis, parabronchitis, and interstitial pneumonia. The lumen of the affected airways contained numerous, large syncytial cells with up to 15 nuclei. The nuclei of these syncytial cells often contained large, eosinophilic inclusion bodies, consistent with herpesvirus. The epithelium of the trachea and air sacs was hypertrophied and contained syncytial cells with intranuclear inclusion bodies similar to the bronchi. In addition, a few intranuclear inclusion bodies were also present in the epithelial cells that line the air capillaries. On ultrastructural examination, the nuclei of degenerating epithelial cells contained clusters of viral nucleocapsid proteins and unenveloped, icosahedral, viral particles that were approximately 90 nm in diameter. In addition, some epithelial cells contained clusters of enveloped viral particles approximately 105 nm in diameter, within the cytocavitary network. These lesions are characteristic of those caused by respiratory herpesvirus of parakeets. 相似文献
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The prevalence of Middle East respiratory syndrome coronavirus (MERS‐CoV) antibodies in dromedary camels in Israel 下载免费PDF全文
Jennifer L. Harcourt Nir Rudoler Azaibi Tamin Eyal Leshem Michal Rasis Michael Giladi Lia M. Haynes 《Zoonoses and public health》2018,65(6):749-754
Middle East respiratory syndrome coronavirus, MERS‐CoV, was identified in Saudi Arabia in 2012, and as of January 29, 2018, there were 2,123 laboratory‐confirmed MERS‐CoV cases reported to WHO (WHO, 2018, https://www.who.int/emergencies/mers-cov/en/ ). Multiple studies suggest that dromedary camels are a source for human MERS‐CoV infection. MERS‐CoV‐specific antibodies have been detected in the serum of dromedary camels across Northern Africa and across the Arabian Peninsula. Israel's geographic location places Israel at risk for MERS‐CoV infection. To date, MERS‐CoV‐related illness has not been reported and the burden of MERS‐CoV infection in the Israeli population is unknown. The seroprevalence of MERS‐CoV‐specific antibodies in Israeli dromedary camels is unknown. The objective of this study was to determine the prevalence of MERS‐CoV seropositivity in dromedary camels in Israel. The prevalence of MERS‐CoV antibodies in Israeli camels was examined in 71 camel sera collected from four farms across Israel by MERS‐CoV‐specific microneutralization (Mnt) assay and confirmed by MERS‐CoV‐specific immunofluorescence assay (IFA). Although this study cannot rule out potential antibody cross‐reactivity by IFA, the presence of bovine coronavirus‐specific antibodies do not appear to impact detection of MERS‐CoV antibodies by Mnt. MERS‐CoV neutralizing antibodies were detectable in 51 (71.8%) camel sera, and no association was observed between the presence of neutralizing antibodies and camel age or gender. These findings extend the known range of MERS‐CoV circulation in Middle Eastern camels. The high rate of MERS‐CoV‐specific antibody seropositivity in dromedary camels in the absence of any reported human MERS cases suggests that there is still much to be learned about the dynamics of camel‐to‐human transmission of MERS‐CoV. 相似文献
85.
Gookin JL Stauffer SH Coccaro MR Marcotte MJ Levy MG 《American journal of veterinary research》2007,68(7):783-787
OBJECTIVE: To determine the optimum reaction conditions and detection limits of PCR assay for identification of Pentatrichomonas hominis in DNA extracted from canine feces. SAMPLE POPULATION: DNA extracted from feces of 4 dogs with diarrhea from which trichomonads were observed, 81 dogs that had feces submitted to a diagnostic laboratory, and 19 dogs residing in a laboratory animal facility. PROCEDURES: Optimum reaction conditions and absolute and practical detection limits of 2 P hominis 18S species-specific primer pairs were determined by use of an in vitro cultivated canine isolate of P hominis in the presence and absence of canine feces. The optimized PCR assay was applied to amplification of P hominis 18S rRNA genes from DNA extracted from the feces of dogs. RESULTS: Under optimized conditions, a primer pair was identified as able to detect as few as 1 P hominis organism/180-mg fecal sample. The PCR assay identified P hominis in diarrheic feces of 4 dogs in which trichomonads were seen by light microscopy. The P hominis genes were not amplified from other fecal samples examined. CONCLUSIONS AND CLINICAL RELEVANCE: Molecular identification of P hominis in feces of 4 dogs with trichomonosis and diarrhea reported here validates the identity of this species in such infections. Sensitive and specific PCR amplification of P hominis 18S rRNA genes from DNA extracted from feces will directly facilitate studies examining pathogenicity of this trichomonad and enable differentiation of P hominis from other known or novel species of trichomonads that may infect the gastrointestinal tract of dogs. 相似文献
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OBJECTIVE: To evaluate the effect of dietary supplementation with sodium chloride (NaCl) on urinary calcium excretion, urine calcium concentration, and urinary relative supersaturation (RSS) with calcium oxalate (CaOx). ANIMALS: 6 adult female healthy Beagles. PROCEDURE: By use of a crossover study design, a canned diet designed to decrease CaOx urolith recurrence with and without supplemental NaCl (i.e., 1.2% and 0.24% sodium on a dry-matter basis, respectively) was fed to dogs for 6 weeks. Every 14 days, 24-hour urine samples were collected. Concentrations of lithogenic substances and urine pH were used to calculate values of urinary RSS with CaOx. RESULTS: When dogs consumed a diet supplemented with NaCl, 24-hour urine volume and 24-hour urine calcium excretion increased. Dietary supplementation with NaCl was not associated with a change in urine calcium concentration. However, urine oxalate acid concentrations and values of urinary RSS with CaOx were significantly lower after feeding the NaCI-supplemented diet for 28 days. CONCLUSIONS AND CLINICAL RELEVANCE: Dietary supplementation with NaCl in a urolith-prevention diet decreased the propensity for CaOx crystallization in the urine of healthy adult Beagles. However, until long-term studies evaluating the efficacy and safety of dietary supplementation with NaCl in dogs with CaOx urolithiasis are preformed, we suggest that dietary supplementation with NaCl be used cautiously. 相似文献
89.
A E Jergens F M Moore J S Haynes K G Miles 《Journal of the American Veterinary Medical Association》1992,201(10):1603-1608
Idiopathic inflammatory bowel disease was the diagnosis for 58 dogs and 26 cats, with signs of persistent gastroenteritis, failed responses to dietary trials, and histologic evidence of cellular infiltrates unrelated to other causes of gastrointestinal tract inflammation. Clinical signs of large intestinal dysfunction, watery diarrhea, vomiting, and anorexia with weight loss were common. Nonspecific hematologic, biochemical, and radiographic abnormalities frequently were observed. Mucosal biopsy specimens, obtained endoscopically, were histologically evaluated for severity of mucosal epithelial damage. Mucosal erythema, friability, enhanced granularity, and ulceration or erosion were the predominant endoscopic lesions. Inflammatory bowel disease lesions of moderate severity predominated in the stomach, duodenum, and colon. Lymphocytic/plasmacytic infiltrates were limited to the lamina propria in biopsy specimens from all regions of the gastrointestinal tract. Inflammatory bowel disease commonly is associated with chronic gastroenteritis in dogs and cats. 相似文献
90.
Calves harboring patent Ostertagia ostertagi or Cooperia punctata were given intradermal injections of O ostertagi 3rd-stage larval antigen. The initial injections were followed 30 days later by a 2nd series of injections. Skin thickness was measured at injection sites for 72 hours after injection. Selected injection sites including saline solution control sites were biopsied at 30 minutes, at 3, 24, 48, and 72 hours, and at 30 days after injection. After the 1st series of injections, there was a clear distinction in dermal reactions between O ostertagi-inoculated calves and C punctata-inoculated calves; after 24 hours, reactions were not seen in the C punctata-inoculated calves. Marked dermal reactions occurred in the O ostertagi-inoculated calves. The reactions at 30 minutes and 3 hours were characterized by slight-to-extensive infiltration of neutrophils and dermal edema. The 24-hour cellular reaction was principally due to neutrophil and eosinophil infiltration with edema and necrosis. Reactions at 48 to 72 hours were due to eosinophils and perivascular accumulations of macrophages and lymphocytes. Necrosis, neutrophils, and edema were present in foci where fragments of nematodes were located. On reinjection, a clear distinction in dermal reactions between calves was not seen based on the type of nematode infection. Thirty days after dermal inoculation, large nodules developed at the site of the initial antigen injection. The nodules were characterized by marked intradermal proliferation of lymphocytes in a follicular pattern with occasional macrophages and rare multinucleated giant cells. 相似文献