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排序方式: 共有456条查询结果,搜索用时 15 毫秒
1.
M C Vickers W J Hartley R W Mason J P Dubey L Schollam 《Journal of the American Veterinary Medical Association》1992,200(11):1723-1725
Seven of 30 canaries in an aviary in New Zealand developed ophthalmic problems. Clinically, 5 birds had unilateral and 2 birds had bilateral lesions characterized by conjunctivitis, crusty exudates on eyelids, and collapse of the eyeball. Microscopic lesions in 12 of 14 eyes examined included inflammation of the choroid and retina, with osseous replacement of the globe in some. Numerous Toxoplasma gondii tachyzoites were seen in the detached retina and vitreous humor of acutely affected birds. The diagnosis of toxoplasmosis was confirmed by immunohistochemical staining with T gondii antiserum. Affected birds had encephalitis, and T gondii was localized in the brains of these by immunohistochemical examination and by use of bioassays in mice. Toxoplasmosis should be considered in differential diagnosis of ophthalmitis in canaries. 相似文献
2.
J P Dubey A N Hamir C A Hanlon C E Rupprecht 《Journal of the American Veterinary Medical Association》1992,200(4):534-536
Serum samples from 427 raccoons (93 from Pennsylvania, 45 from New Jersey, 72 from South Carolina, 68 from Virginia, 30 from Iowa, and 119 from Ohio) were evaluated for Toxoplasma gondii antibodies in dilutions of 1:25, 1:50, and 1:500. The distribution of T gondii antibody titers was less than 1:25 for 212 raccoons (49.6%), 1:25 for 34 raccoons (7.9%), 1:50 for 117 raccoons (27.4%), and greater than or equal to 1:500 for 64 raccoons (14.9%). Tissue cysts were seen in the liver, and tachyzoites were in the brain of a raccoon with abnormal neurologic signs and concurrent infection with canine distemper virus. Organisms in the liver were stained with anti-T gondii serum, and the raccoon had a T gondii titer of 1:160 in the agglutination test. 相似文献
3.
J C Silva S Ogassawara M F Marvulo J S Ferreira-Neto J P Dubey 《Journal of zoo and wildlife medicine》2001,32(3):349-351
Serum samples from 37 captive exotic felids in 12 zoos from six Brazilian states were assayed for antibodies to Toxoplasma gondii by the modified agglutination test using formalin-fixed whole tachyzoites. Titers greater than or equal to 1:20 were considered positive. Antibodies to T. gondii were found in 24 of 37 (64.9%) felids, including one European lynx (Lynx lynx), two jungle cats (Felis chaus), two servals (Leptailurus serval), two tigers (Panthera tigris), three leopards (Panthera pardus), and 14 of 27 lions (Panthera leo). This is the first serologic analysis for T. gondii infection in exotic wild felids from Brazilian zoos. 相似文献
4.
The ultrastructure of sarcocysts of macro- and microscopic species of Sarcocystis was compared from naturally infected water buffalo from India. Grossly visible sarcocysts had walls consisting of cauliflower-like villar protrusions, typical of S. fusiformis. The sarcocyst wall of the microscopic species of Sarcocystis was 6.4 microns thick and consisted of tightly packed conical villar protrusions that were 9.6 microns long and 3.7 microns wide at the base. At approximately 3 microns above the base, the distal two-thirds of the villar protrusion became conical shaped and was bent laterally at an angle of 45 degrees to the sarcocyst surface. The granular layer beneath the villar protrusions was 0.9 microns thick. In S. levinei the granular layer was 1.9 microns thick, the villar protrusions were narrow and it had a highly undulating primary cyst wall. Whether the microscopic S. levinei-like sarcocysts of Indian and Malaysian water buffalo are distinct species of Sarcocystis will require further investigation. 相似文献
5.
Pooja A. R. Yogesh Pandey Meeti Punetha Anju Kala Hari Abdul Samad Gyanendra Singh Vikrant Singh Chouhan 《Reproduction in domestic animals》2023,58(1):60-72
The aim of the present study was to evaluate the expression and localization of lymphangiogenic factors (VEGF-C and VEGF-D), their receptor (VEGFR3) and lymphatic endothelial marker (LYVE1) in buffalo placenta during early pregnancy [EP], and to investigate the functional role of lymphangiogenic growth factors in placental lymphangiogenesis. The mRNA and protein expression of VEGF-C, VEGF-D, their receptor VEGFR3 and LYVE1 showed significant expression in EP1 (29–42 days) and EP2 stages (51–82 days) both in caruncle (maternal part) and cotyledon (foetal part) of the buffalo placenta. Immunoreactivity of VEGF-C, VEGF-D and LYVE1 was observed around the endometrial gland, in lymphatics and trophoblast cells, whereas VEGFR3 mainly localized in lymphatics of the caruncle and cotyledons. Cultured trophoblast cells were treated with VEGF-C/VEGF-D (50, 100 and 150 ng/ml) and combined doses of VEGF-C and VEGF-D (150 ng/ml) each for different time durations (24, 48 and 72 h). The mRNA expression of LYVE1 and PCNA was significantly (p < .001) upregulated with VEGF-C and VEGF-D and combined treatment (@150 ng/ml), as well as significantly downregulating Caspase-3 at 48 and 72 h. Thus, the present study provides evidence that lymphangiogenic factors are expressed in buffalo placental compartments and they may play a significant role in the regulation of placental function in water buffaloes. 相似文献
6.
7.
At least three species of Sarcocystis (S. neurona, S. falcatula, S. speeri) have recently been shown to use opossums of the genus Didelphis as their definitive host. In order to evaluate the evolutionary relationships among Sarcocystis spp. isolates from the Americas, and to determine whether organisms representing the same parasite lineages are transmitted north and south of the Panamanian isthmus, we inferred the phylogenetic relationships from nucleotide sequence variation in parasites isolated from three opossum species (D. virginiana, D. albiventris, D. marsupialis). In particular, we used variation in the 25/396 marker to compare several isolates from Brazil, Argentina, and the United States to each other and to cloned S. neurona and S. falcatula whose morphology and host affinities have been defined in the laboratory. S. neurona was identified from a Brazilian D. albiventris, as well as from North American D. virginiana. Parasites resembling the Cornell isolate of S. falcatula are transmitted both south and north of the Panamanian isthmus by D. albiventris and D. virginiana, respectively. Distinct attributes at two genetic loci differentiated a Brazilian isolate of S. falcatula from all other known parasite lineages. We confirm S. neurona as the causative agent of recently reported neurologic disease in Southern sea otters, Enhydra lutris nereis. And we found that S. speeri could not be compared to the other opossum-derived Sarcocystis isolates on the basis of nucleotide variation at the 25/396 locus. The widespread distribution of certain species of Sarcocystis may derive from their ability to parasitize migratory bird hosts in their intermediate stage. 相似文献
8.
Dual Sarcocystis neurona and Toxoplasma gondii infection was observed in a Northern sea otter from Washington, USA. The animal was found stranded, convulsed, and died shortly thereafter. Encephalitis caused by both S. neurona and T. gondii was demonstrated in histological sections of brain. Immunohistochemical examination of sections with S. neurona specific antisera demonstrated developmental stages that divided by endopolygeny and produced numerous merozoites. PCR of brain tissue from the sea otter using primer pairs JNB33/JNB54 resulted in amplification of a 1100 bp product. This PCR product was cut in to 884 and 216 bp products by Dra I but was not cut by Hinf I indicating that it was S. neurona [J. Parasitol. 85 (1999) 221]. No PCR product was detected in the brain of a sea otter which had no lesions of encephalitis. Examination of brain sections using T. gondii specific antisera demonstrated tachyzoites and tissue cysts of T. gondii. The lesions induced by T. gondii suggested that the sea otter was suffering from reactivated toxoplasmosis. T. gondii was isolated in mice inoculated with brain tissue. A cat that was fed infected mouse brain tissue excreted T. gondii oocysts which were infective for mice. This is apparently the first report of dual S. neurona and T. gondii in a marine mammal. 相似文献
9.
10.
J P Dubey M L Porterfield 《Journal of the American Veterinary Medical Association》1986,188(11):1312-1313
Multifocal areas of necrosis and infiltrations of mononuclear cells were seen in lung specimens of an equine fetus aborted 2 months before term. Extracellular and intracellular protozoa were seen in the alveolar tissue. Individual organisms were 4 microns by 2.5 microns, and cyst-like structures were 25 microns by 18 microns. Organisms did not stain with periodic acid-Schiff or by use of the immunoperoxidase and peroxidase-antiperoxidase method for Toxoplasma gondii. Twelve days after abortion, the mare had serum antibody titer of less than 1:10 against T gondii. 相似文献