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91.
Fish Physiology and Biochemistry - The present study was carried out to evaluate the genotoxic potential of nutritional quality of feed, using erythrocytic nuclear abnormalities assay in Nile...  相似文献   
92.
93.
Endoscopic removal of esophageal and ruminal foreign bodies was successfully performed in 5 Holstein-Friesian calves under sedation or general anesthesia by using an electrocautery snare or a wire-guided Dormi basket. This report describes the endoscopic manipulations, treatment, and outcomes of esophageal foreign body removal in these calves.  相似文献   
94.
An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections.  相似文献   
95.
The stifle is a large and complex joint in quadrupeds, including horses, making the diagnosis of stifle diseases a challenge for the clinician. The detection of “stifle syndrome” during acupuncture examination of the equine stifle may be useful for diagnosis of stifle diseases in horses. The aim of the present study was to describe stifle syndrome diagnosis in horses. From 2001 through 2012, 810 athletic horses involved in different disciplines were examined using the technique of acupuncture diagnosis. Stifle syndrome was suspected when the following points were reactive: the sacral point suggestive of stifle disease located at the sacral origin of the biceps femoris muscle, bladder (BL)-20, BL-21, and stomach (ST)-30, together with the three local points in the muscle groove of the posterolateral aspect of the thigh. The diagnostic protocol included radiography and/or ultrasonography in certain cases. The horses were evaluated because of reduced athletic performance, routine or prepurchase examination, hind limb lameness, refusal to jump, inappetence, upward fixation of the patella, thoracolumbar spine or sacroiliac pain, suspensory lesion, and front hoof problems, and 86 (9.4%) were diagnosed with stifle syndrome. The sacral acupuncture point suggestive of stifle syndrome correlated with BL-21, local stifle points, gall bladder (GB)-27, spleen-13, BL-23, BL-52, BL-26, and/or GB-25, ST-30, BL-54 (P < .0001), and BL-20 (P = .003). Twenty-two (25.6%) of the 86 horses with stifle syndrome underwent ultrasonography and/or radiography, and lesions were detected in 21. In conclusion, acupuncture for diagnosis of stifle disease may be considered a diagnostic method to be included in routine clinical examination of horses, and its reproducibility shall be investigated in further studies.  相似文献   
96.
A 13-year-old Lusitano stallion was referred to our institution with a history of severe hematuria for 8.5 months. The origin of the hematuria was determined to be the left kidney. The diagnostic workup failed to identify obstructive, infectious, or neoplastic conditions. The history and ultrasonographic examination suggested a chronic condition. The stallion was subjected to left nephrectomy because of the persistent hematuria and anemia. A histopathological examination detected lesions, which were compatible with chronic nephritis and vascular renal hypertension. It is hypothesized that changes in the normal parenchymal architecture produced a vascular aberration that led to renal hypertension, with subsequent blood extravasation and hematuria. The horse recovered completely after nephrectomy.  相似文献   
97.
Brucella ovis causes ram contagious epididymitis, a disease for which a specific vaccine is lacking. Attenuated Brucella melitensis Rev 1, used as vaccine against ovine and caprine brucellosis caused by B. melitensis, is also considered the best vaccine available for the prophylaxis of B. ovis infection, but its use for this purpose has serious drawbacks. In this work, two previously characterized B. ovis attenuated mutants (Δomp25d and Δomp22) were evaluated in mice, in comparison with B. melitensis Rev 1, as vaccines against B. ovis. Similarities, but also significant differences, were found regarding the immune response induced by the three vaccines. Mice vaccinated with the B. ovis mutants developed anti-B. ovis antibodies in serum of the IgG1, IgG2a and IgG2b subclasses and their levels were higher than those observed in Rev 1-vaccinated mice. After an antigen stimulus with B. ovis cells, splenocytes obtained from all vaccinated mice secreted similar levels of TNF-α and IL12(p40) and remarkably high amounts of IFN-γ, a crucial cytokine in protective immunity against other Brucella species. By contrast, IL-1α -an enhancer of T cell responses to antigen- was present at higher levels in mice vaccinated with the B. ovis mutants, while IL-10, an anti-inflammatory cytokine, was significantly more abundant in Rev 1-vaccinated mice. Additionally, the B. ovis mutants showed appropriate persistence, limited splenomegaly and protective efficacy against B. ovis similar to that observed with B. melitensis Rev 1. These characteristics encourage their evaluation in the natural host as homologous vaccines for the specific prophylaxis of B. ovis infection.  相似文献   
98.
Neospora caninum has been detected only sporadically in cases of ovine abortion, and it has therefore traditionally been considered as an unimportant parasite in small ruminants. This study was carried out with the aim of identifying the pathogen causing serious reproductive problems on a commercial sheep farm. Sera from all rams and ewes tested negative for antibodies against Border disease virus, Schmallenberg virus and Coxiella burnetii, and infections by these agents were therefore ruled out. Nevertheless, seropositivity to N. caninum and/or Toxoplasma gondii was detected, although the seroprevalence was higher in the case of N. caninum. The percentage of lambings and the number of lambs per dam were significantly lower in ewes that were seropositive to N. caninum while no effect on these parameters was detected in ewes that were seropositive to T. gondii. There was also no evidence of infection by T. gondii in the foetal/lamb tissues analyzed by PCR and/or immunohistopathological techniques. On the contrary, the DNA of N. caninum was detected in 13 out of 14 foetuses/lambs descendant from dams seropositive to this parasite. Characteristic lesions caused by N. caninum and/or its antigen were also detected. Genotyping of the N. caninum DNA revealed only two closely related microsatellite multilocus genotypes. The results clearly demonstrate that infection by N. caninum was the cause of the low reproductive performance of this sheep flock.  相似文献   
99.
In South America, the whitefly Aleurotrachelus socialis is one of the principal pests of cassava (Manihot esculenta Crantz), reaching high population levels throughout the Andean region. Management of this species is primarily based upon the use of insecticides, while biological control has received limited attention. Till present, knowledge of A. socialis natural enemies is restricted to occasional records of predators and parasitoids. In this study, we developed PCR primer sets specific for the cassava whitefly, A. socialis, to identify their predator community in Colombian cassava. Eleven percent of 586 predator specimens (representing 131 taxa from 29 families) tested positive for cassava whitefly DNA. Of the 21 predator taxa that consumed cassava whiteflies, an unidentified netwing beetle (Lycidae), an unidentified spider species (Araneae), Harmonia axyridis (Coleoptera: Coccinellidae), a Cereaochrysa sp. (Neuroptera: Chrysopidae), and a Leucochrysa sp. (Chrysopidae) were the taxa that consumed cassava whiteflies most frequently under field conditions. Two abundant predators in the system, Delphastus sp. (Coccinellidae) and the long-legged fly, Condylostylus sp. (Diptera: Dolichopodidae), were both positive for whitefly DNA, but did not have the strongest trophic linkage to the pest relative to other predators. This study shows that a diverse predator community affects cassava whitefly in southern Colombia, and provides the groundwork for the design of cassava production systems with minimal pesticide inputs.  相似文献   
100.
Shrubs are important microsites that facilitate seedling performance in abiotically stressed environments. However, shrub facilitation might work differently in ecosystems with high biotic stress (e.g., ungulate-dominated environments). We wonder whether ungulates through their preferences for different shrubs affect the facilitation process of seedlings, and whether this process remains consistent across different levels of abiotic stress. We study seedling performance (survival and growth) of a Mediterranean oak (Quercus pyrenaica) in three microsites (open, preferred and non-preferred shrubs by ungulates) for two contrasting climatic environments and throughout a complete growing season (increasing abiotic stress). Overall, there was a positive effect of shrubs in seedling survival. We found a microsite effect on seedling growth but this effect differed depending on the abiotic environment, with seedlings growing better in open microsites in the less stressful site. The larger abiotic context (climate) played an important role in determining which microsite is the most favorable for seedling growth but not necessarily for the eventual survival of seedlings. Wild ungulates started to damage seedlings early in the growing season, whereas abiotic stress (desiccation) affected mostly those plants that were not previously attacked by animals, showing the hierarchical effect (earlier and longer effect) of the biotic over the abiotic mortality agents. Non-preferred shrubs worked better as nurse shrubs only under high ungulate pressure. From the abiotic perspective, preferred and non-preferred shrubs did not apparently differ in the facilitation effect. Importantly, we found a greater facilitative effect of shrubs on the survival than on the growth of seedlings.  相似文献   
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