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31.
This study examined the effect of treating mares with equine pituitary extract (EPE) in combination with human chorionic gonadotropin (hCG; EPE/hCG) on the recovery rate of immature oocytes by ovum pick-up (OPU) and on oocyte morphology. Ten mares were subjected to each of two treatments in a random sequence: superstimulated with EPE (25 mg, twice daily) and treated with hCG (2,500 IU) or control (no exogenous treatment). The cytoplasmic morphology of oocytes recovered was evaluated through transmission electron microscopy. Follicular fluid was collected at aspiration for progesterone analysis, which was performed by radioimmunoassay. The EPE/hCG did not increase the oocyte recovery rate from immature follicles when compared with the controls (15.5% and 16.7%, respectively). A significantly higher oocyte recovery rate per mare was observed (70% versus 50%). However, precocious granulosa cell expansion was observed with EPE/hCG treatment in contrast to the control (64.4% and 33% of follicles with expanded cumulus, respectively), and increased intrafollicular progesterone concentration was also seen (158.80 ng/mL versus 82.05 ng/mL). The ultrastructural analysis of oocytes from both groups showed morphologic features related to immaturity. Numerous vesicles containing cortical granules were found, distributed in clusters into the cytoplasm, and junctional complexes were still seen between oocyte and granulosa cells. In conclusion, EPE/hCG treatment induced some follicular modifications, but the recovery rate was not increased. All oocytes examined presented signs of immaturity.  相似文献   
32.
A case of a dog with a long-term inflammatory skin disorder due to infection with methicillin-resistant Staphylococcus pseudintermedius (MRSP) is described. After initial diagnostics of MRSP, follow-up swabs of the dog (nose, skin) were taken twice after four and seven weeks. MRSP was constantly isolated from the skin and once from the nose. Since infected humans might be a source of reinfection, the owners of the dog were screened (nasal) three times during their pet's therapy. Thereby, the male owner was found to be colonized with MRSP once in the first sampling round. Comparative typing of all MRSP-isolates by pulsed-field gel electrophoresis (PFGE), SCCmec typing, multilocus sequence typing (MLST), spa typing, PCR-detection of the leukotoxin encoding operon (LukI) and the Staphylococcus intermedius-exfoliative toxin (SIET) as well as antimicrobial resistance profiling by broth microdilution revealed that all five MRSP isolates from the dog and the single isolate from the owner were indistinguishable by any of the applied methods. All isolates were assigned to a certain strain, a multidrug-resistant MRSP belonging to sequence type (ST) 71, spa type (t)05, harbouring SCCmecIII as well as the genes encoding LukI and SIET. In this case, a number of reasons might have contributed to therapy failure and re-infection, respectively (e. g. contact to other MRSP-colonized dogs, contact to MRSP-colonized humans, refusal to clip the dog's fur). In addition, MRSP-contaminated objects or surfaces in the household, which were difficult to disinfect or simply not considered as a potential source of MRSP, might have served as a source of re-infection. These results envision the possibility of a dog-to-human transmission of MRSP and the relevance of this aspect as a potential source of re-infection in cases of bacterial-supported long-term skin disorders in canine patients. First cases of MRSP infections in humans have been described only recently. However, the general pathogenic potential of multidrug resistant MRSP in humans is unknown so far and needs further investigation.  相似文献   
33.
This report describes a case of cutaneous pythiosis in a 6‐year‐old female mixed breed dog, from the central west region of São Paulo State, Brazil. The cytological and histopathological analyses showed an intense inflammatory infiltrate with presence of numerous hyphal elements, suggesting infection due to Pythium insidiosum. The diagnosis was confirmed by nested‐PCR, which was carried out with specific primers derived from the ribosomal DNA region. The pathogen occurs in Brazil and veterinarians should be aware of the importance of correctly diagnosing this disease and differentiating it from other fungal diseases.  相似文献   
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Tropical Animal Health and Production - As in most of the African continent, the status of hepatitis E virus (HEV) infection in domestic animals in São Tomé and Príncipe, an...  相似文献   
37.
Neubauer C  Hess M 《Avian diseases》2006,50(4):620-623
Three-day-old specific pathogen-free chickens (n = 24) located in isolators were inoculated orally with Helicobacter pullorum. One group (n = 12) was infected with a H. pullorum field isolate from human origin, another one (n = 12) with the American Type Culture Collection H. pullorum reference isolate 51801 originating from chickens. Both isolates were positive for cytolethal distending toxin, investigated using a polymerase chain reaction (PCR). A third group (n = 4) was kept as a negative control. Starting on day 7 of life, birds from each group were euthanatized at different time points up to 35 days. Various organ samples were taken aseptically and processed by culture and a H. pullorum-specific PCR. In the group infected with the human isolate the nucleic acid of H. pullorum was detected in the caecal tonsils and caeca of 12 and 11 birds, respectively. Live bacteria were cultivated from the caecal tonsils and caeca of five birds 24 and 31 days postinfection. Live bacteria were also isolated from the heart of one bird, whereas PCR had to be used to detect the nucleic acid of H. pullorum in the gallbladder of four birds. No live bacteria were reisolated at any time from birds infected with the avian isolate, but bacterial nucleic acid was detected in the caeca of five birds and in the gallbladder of one. In both groups neither live H. pullorum nor its nucleic acid were detected in the liver, spleen, and duodenum. Compared to the avian H. pullorum isolate the human isolate proved to be more invasive. No obvious clinical symptoms or disease was seen in the chickens during the entire experiment. The reisolation of live bacteria at the end of the experiments indicates that H. pullorum could enter the food chain even after early infection in birds. Furthermore, PCR was demonstrated to be helpful in tracing these fastidious bacteria.  相似文献   
38.
Various methods have been developed to mitigate the adverse effects of the Federal Columbia River Power System on juvenile Pacific salmon out-migrating through the Columbia River basin. In this study, we found that hatchery-reared spring Chinook salmon Oncorhynchus tshawytscha in the river are in varying degrees of health, which may affect delayed mortality and the assessment of the effectiveness of management actions to recover listed stocks (e.g., barging fish downstream versus leaving fish in the river). A laboratory disease challenge with Listonella anguillarum was completed on fish from Rapid River Hatchery and Dworshak National Fish Hatchery (NFH) with different out-migration histories: (1) transported by barge, (2) removed from the river before barging, or (3) left to travel in-river. Barged fish from Rapid River Hatchery experienced less mortality than fish from Dworshak NFH. No statistical differences were found between the hatcheries with fish that had in-river out-migration histories. We suggest that the stressors and low survival associated with out-migration through the hydropower system eliminated any differences that could have been present. However, 18-25% of the fish that were barged or collected before barging died in the laboratory before the disease challenge, compared with less than 2% of those that traveled in-river. Owing to disproportionate prechallenge mortality, the disease-challenged populations may have been biased; thus, they were also considered together with the prechallenge mortalities. The synthesis of prechallenge and disease-challenged mortalities and health characteristics evaluated during out-migration indicated that the benefit of barging was not consistent between the hatcheries. This finding agrees with adult survival and delayed mortality estimates for the individual hatcheries determined from adult returns. The results suggest that the health status of fish and their history before entering the hydropower system (hatchery of origin and out-migration path) are critical variables affecting the conclusions drawn from studies that evaluate mitigation strategies.  相似文献   
39.
To evaluate the association of oral Treponema (T.) spp. with severity of canine periodontitis, subgingival plaque samples of dogs of various breeds undergoing surgery were investigated. A wide range of oral Treponema spp. was analysed by a molecular and culture-independent approach applying DNA-DNA dot blot hybridization analysis and fluorescence in situ hybridization using Treponema specific oligonucleotide probes specific for phylogenetic groups I-VII of oral treponemes as well as probes specific for T. socranskii and T. denticola. To assess the periodontal status of affected dogs clinical parameters were measured and the periodontal status was classified from grade 0 (physiological periodont) to 3 (severe periodontitis). The periodontal status correlated significantly with an increasing concentration of volatile sulfur compounds (VSC, r=0.854) determined with a Halimeter, indicating a positive correlation between the presence of VSC-producing bacteria and periodontitis. In this study Treponema spp. of phylogenetic groups III, V-VII were not detected in any sample, whereas T. denticola-like treponemes were found only in 2 of 51 animals. However, treponemes belonging to phylogenetic groups I, II and IV of oral treponemes or T. socranskii were found in up to 64.84% of the dogs. The detection rate of Treponema spp. was significantly associated with an increased periodontal status. Treponemes present in periodontal lesions were also visualized by fluorescence in situ hybridization of gingival biopsies showing Treponema spp. not only in the microbial biofilm but also within the gingival tissue. The data presented here indicate that oral Treponema spp. are associated with canine periodontitis. Similar to human periodontitis, treponemes of groups I, II and IV and T. socranskii were found more frequently the higher the degree of periodontitis was.  相似文献   
40.
Spongiform neurodegenerative disease in a Persian kitten   总被引:1,自引:0,他引:1  
A congenital encephalopathy with spongiform degeneration and prominent neuronal apoptosis was observed in a 4-month-old Persian male cat with a history of depressed mental status and ataxia. On clinical examination, signs included right head tilt, ventroflexion of the head and neck, and tetraparesis. Histological examination of the central nervous system revealed multifocal, bilateral and symmetrical vacuolar degeneration of the neuropil, mainly involving the cerebellar and vestibular nuclei area, the caudal colliculi, the mesencephalic nuclei, the tegmental area and the deeper layer of the cerebral cortex. Accumulation of phosphorylated neurofilaments was detected in neuronal perikarya of the deep cortical layers, hippocampus and thalamus. Numerous pyknotic and apoptotic neurons were also observed in the cerebral cortex. These neuropathological changes differ from those observed in previous reports of spongiform degeneration of the grey matter in cats and were suggestive of a congenital neurodegenerative disease.  相似文献   
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