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61.
Gennari SM Canón-Franco WA Yai LE de Souza SL Santos LC Farias NA Ruas J Rossi FW Gomes AA 《Veterinary parasitology》2004,121(3-4):337-340
The prevalence of anti-Toxoplasma gondii antibodies was evaluated by the indirect immunofluorescent-antibody test in serum of 57 wild canids from three different species: Lycalopex gymnocercus, Cerdocyon thous and Dusicyon vetulus from the northeast, southeast and southern regions of Brazil. The prevalence was 35.1%, with 20 of the 57 canids demonstrating antibodies anti-T. gondii at dilutions of 1:16 in 2, 1:32 in 4, 1:64 in 2, 1:128 in 2, 1:256 in 6, 1:512 in 2 and 1:2048 in 2 animals. None of the D. vetulus were positive. Among the L. gymnocercus 11 (91.7%) of the 12 samples were positive and among C. thous 9 (60%) of the 15 had antibodies anti-T. gondii. 相似文献
62.
Preziuso S Renzoni G Allen TE Taccini E Rossi G DeMartini JC Braca G 《Veterinary microbiology》2004,104(3-4):157-164
Maedi visna virus (MVV) vertical transmission in sheep via infected colostrums is a very important route of infection in lambs. To verify colostral transmission and to study early viral entry in lambs, colostrum samples, and small intestine and mesenteric lymph nodes of lambs born from experimentally infected ewes were examined by histopathology, immunohistochemistry (IHC) and in situ hybridisation (ISH) studies. In particular, newborn lambs were naturally fed maternal colostrum and humanely killed at 10, 24, 48, 72, 96 h and 7 and 10 days after birth; two caesarian-derived lambs served as uninfected controls. No lesions suggestive of MVV infection were found, but marked immunoreactions for MVV capsid antigen (CA, p28) were detected in lambs fed maternal colostrum and in macrophages cultured from colostrum. IHC results in lambs suggest an initial viral absorption by intestinal epithelial cells at the tip of the villi, passage to mononuclear cells in the lamina propria and involvement of ileum Peyers' patches and mesenteric lymph nodes, with different staining patterns depending on infection times. ISH on intestinal sections of the 72 h lamb revealed the presence of proviral DNA in epithelial cells at the tip of the villi, suggesting a role for these cells in early MVV replication. The results contribute to knowledge about the pathogenesis of ovine lentivirus infection suggesting that the small intestine and mesenteric nodes are the sites of entry and propagation of MVV in lambs fed colostrums from infected ewes. 相似文献
63.
1. A polymerase-chain-reaction (PCR)-based test was adapted to sex the lesser rhea. Feathers instead of blood were used as the source of DNA. 2. The primers used allowed the assignment of sex by amplification of Z and W chromosome linked sequences. 3. This method proved to be safe, accurate and non-invasive. 4. The W chromosome linked fragment was sequenced and compared to other ratite sequences. 相似文献
64.
Ferroglio E Pregel P Accossato A Taricco I Bollo E Rossi L Trisciuoglio A 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(1):30-33
Intradermal tests were carried out on 18 horses with clinical signs of Culicoides hypersensitivity (CHS) and 23 horses without clinical signs of CHS, and sera from these horses were analysed by SDS-PAGE and Western blotting (W-B). Intradermal injections of 0.1 ml of 25 microg/microl sterile Culicoides extract, 0.1 ml of 1:10,000 histamine (positive control) and 0.1 ml of physiological saline (negative control) were made in the dermis of the middle region of the neck. Analysis of reactions indicated that a 1 cm wheal and a skinfold thickness >10% at 24 h represented a valid cut-off between horses with and without CHS. In these conditions the test, even in winter when clinical signs were absent, had 100% sensitivity and specificity. The W-B was performed after running Culicoides extract on a 12% polyacrylamide gel. The test revealed the presence of several bands with molecular weight ranging from 6 to 200 kDa. In particular, a band of 65 kDa was predominantly found in hypersensitive horses by using an anti-IgE antibody while in normal horses the same band was mainly detected by using an anti-IgG antibody. Our results demonstrated that the skin test is a valid diagnostic test, with high sensitivity and specificity and that the band of about 65 kDa probably corresponds to the allergen involved in the pathogenesis of CHS. 相似文献
65.
Although primary infection of grapevines by Plasmopara viticola requires splash dispersal of inoculum from soil to leaves, little is known about the role of rain in primary inoculum dispersal. Distribution of rain splashes from soil to grapevine canopy was evaluated over 20 rain periods (0.2 to 64.2 mm of rain) with splash samplers placed within the canopy. Samplers at 40, 80, and 140 cm above the soil caught 4.4, 0.03, and 0.003 drops/cm(2) of sampler area, respectively. Drops caught at 40 and 80 cm (1.5 cm in diameter) were larger than drops at 140 cm (1.3 cm). Leaf coverage by splashed drops, total drop number, and drop size increased with an increase in the maximum intensity of rain (mm/h) during any rain period. Any rainfall led to infection in potted grapevines placed outside on leaf litter containing oospores, if the litter contained germinated oospores at the time of rain; infection severity was unrelated to rain amount or intensity. Results from vineyards also indicate that any rain can carry P. viticola inoculum from soil to leaves and should be considered a splash event in disease prediction systems. Sampling for early disease detection should focus on the lower canopy, where the probability of splash impact is greatest. 相似文献
66.
67.
Collodel G Castellini C del Vecchio MT Cardinali R Geminiani M Rossi B Spreafico A Moretti E 《Reproduction in domestic animals》2012,47(3):372-378
In a previous study, we reported the short- and long-term effects of bacterial lipopolysaccharide (LPS)-induced inflammation on rabbit sperm quality. This study was aimed at exploring the spermatogenesis of the rabbit model focussing on the possible damages occurring to the testis and ejaculated sperm. Twenty New Zealand White rabbit bucks were divided into two groups. One group was inoculated intra-peritoneally with LPS, the other group, considered as control, was treated under the same conditions with saline only. Semen samples were collected before LPS injection, the 7th, 14th, 21st, 30th, 45th, 60th and 90th day after LPS treatment. Semen parameters were evaluated following international guidelines. The kinetic characteristics of ejaculated sperm were analysed using a computer-assisted sperm analyzer and the ultrastructural characteristics were explored by transmission electron microscopy (TEM). On the 7th, 14th and 30th day, testis from treated rabbits and controls were obtained. Testis samples were analysed by light microscopy and TEM. The induced LPS lesions in the testis became evident the 7th day after treatment, with a decrease in germinal cells and with an increase in structurally altered Sertoli cells; normal spermatogenesis was restored on the 30th day. The testicular damages observed on day 7 were probably responsible for the reduction in sperm concentration and motility and the ultrastructural alterations that were detected in the ejaculated sperm on the 14th through the 30th days after treatment. In conclusion, rabbit buck treated with LPS could be a useful model for studying the effect of an induced systemic inflammation on spermatogenesis. 相似文献
68.
Leblanc AK Miller AN Galyon GD Moyers TD Long MJ Stuckey AC Wall JS Morandi F 《Veterinary radiology & ultrasound》2012,53(3):348-357
Palladia(TM) (toceranib phosphate-Pfizer Animal Health) is a novel orally administered receptor tyrosine kinase inhibitor (TKI) approved for treatment of canine mast cell tumors. Receptor tyrosine kinase dysregulation leads to tumor growth, progression, and metastasis. Toceranib's targets include vascular endothelial growth factor receptor (VEGFR-2/Flk-1/KDR), platelet-derived growth factor receptor, and kit. Positron Emission Tomography/Computed Tomography (PET/CT) is used commonly to diagnose, prognosticate, and monitor response to antineoplastic therapy in human patients. In this study, serial PET/CT imaging with (18) F-fluorodeoxyglucose ((18) FDG) was used to assess response to toceranib therapy in dogs with measurable solid malignancies. Six tumor-bearing dogs underwent tumor assessment using both standard RECIST criteria and PET/CT prior to and at a median of 5 weeks postinitiation of toceranib treatment. Toceranib was prescribed initially at a target dose 3.25 mg/kg PO q48 h, with subsequent modifications based on observed toxicity. Treatment was continued in patients achieving stable disease with acceptable drug tolerance. One dog was maintained on drug despite dose modification due to toxicity; measurable clinical and image-based responses were seen after 10 weeks of therapy. All others had stable or progressive disease based on clinical restaging and PET/CT at first recheck. . Due to discordance with anatomic and metabolic imaging, further studies are needed to investigate the role of molecular imaging in assessment of drug response and identify other potential molecular targets of toceranib. 相似文献
69.
Objective To determine the analgesic, sedative, motor, cardiac and respiratory effects of epidural clonidine in cattle. Study design Prospective randomized study. Animal population Six healthy male cattle weighing between 236 and 365 kg. Methods To investigate the effect of epidural clonidine, the animals received 2 and 3 µg kg?1 of clonidine diluted to 8 mL with 0.9% saline. Two treatments were utilized as controls. The animals from the first control treatment received 2% lidocaine (0.4 mg kg?1) and those from the second received an equal volume of 0.9% saline. Each animal received each treatment in random order. Evaluations of analgesia, sedation, muscle relaxation, heart rate, respiratory rate and rectal temperature were obtained at 0 (basal), 2, 5, 10, 15 and 30 minutes after epidural injection, and then at 30‐minute intervals until loss of analgesia occurred. All the animals received a standard noxious stimulus consisting of needle insertion into the skin and deep muscle; a 4‐point scale was used to score the response. A second scale was used to score sedation and a third for muscle relaxation. Results Both doses of clonidine were effective in producing analgesia of the tail, perineum, and upper hindlimb. Complete analgesia was present before (mean ± SE = 9 ± 4 vs. 19 ± 9 minutes) and lasted longer (311 ± 33 vs. 192 ± 27 minutes) for the 3 µg kg?1versus the 2 µg kg?1 dose, respectively. A dose‐dependent sedative effect of clonidine was also observed, with a peak effect between 60 and 180 minutes. No effects on heart or respiratory rates were observed with either dose of clonidine. Conclusions Epidural administration of 2 and 3 µg kg?1 of clonidine in cattle in this study provided bilateral perineal analgesia/anesthesia with a dose‐dependent onset and duration of action. Clinical relevance Further studies are required to determine whether the analgesia is sufficient for surgery. 相似文献
70.
Rebecca Manley Andrea R. Matthews Federica Morandi George A. Henry Katherine H. DeAnna Gordon Conklin Ann Reed 《Veterinary radiology & ultrasound》2013,54(3):253-262
Motion artifact is an important limiting factor for abdominal magnetic resonance imaging (MRI) in veterinary patients. The purpose of this study was to determine the effects of pulse sequence on abdominal MRI diagnostic quality in dogs. Ten normal dogs were each scanned using 16 MRI pulse sequences. Sequences included breath‐holding sequences, respiratory navigation sequences, and traditional spin‐echo sequences. Four observers independently scored diagnostic quality for each sequence based on the appearance of specific organs, overall diagnostic quality, and degree of artifactual interference. Signal‐to‐noise ratio and contrast‐to‐noise ratio were also calculated for each sequence. The sequence with the highest overall mean diagnostic quality score was the dorsal T2 turbo spin echo (TSE) with fat saturation and breath‐holding. The sequence with the lowest mean diagnostic quality score was the dorsal T2 fast spin echo. The sequence with the highest signal‐to‐noise ratio for all evaluated organs was the sagittal T1 spin echo. Signal‐to‐noise and contrast‐to‐noise ratios did not correlate with subjective assessment of overall diagnostic quality for the majority of the sequences evaluated (P < 0.05). The three sequences considered to have the highest diagnostic quality for the cranial abdomen were the dorsal T2 TSE with fat saturation and breath‐hold, transverse T1 turbo fast low‐angle shot gradient echo with breath‐hold, and dorsal T2 half‐Fourier acquisition single shot TSE with respiratory navigation. These sequences had short acquisition times, yielded studies of similar diagnostic quality, provided complementary information, and are therefore recommended for routine canine abdominal MRI protocols. 相似文献