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991.
The aim of the present study was to analyze the time-course of t-butyl hydroperoxide-induced changes in lipid peroxidation, fatty acid composition and chemiluminescence intensity in rat, caprine, equine and bovine erythrocyte ghosts. A relatively high content of arachidonic acid (C20:4 n6) and docosahexaenoic acid (C22:6 n3) was characteristic of the rat erythrocyte ghosts. The fatty acid composition of native erythrocyte ghosts obtained from caprine, equine and bovine was characterized by a high content of oleic acid (C18:1 n9) and a low content of the peroxidable polyunsaturated fatty acids (C20:4 n6 and C22:6 n3). The proportion of linoleic acid (C18:2 n6) was higher in equine and bovine compared to rat and caprine. Increase in lipid peroxidation in rat erythrocyte ghosts was maximal within 12 min of incubation, t-butyl hydroperoxide concentration dependent and was paralleled by a decrease in C18:2 n6, C20:4 n6 and C22:6 n3 and an increase in chemiluminescence formation. Polyunsaturated fatty acids (PUFAs) present in rat erythrocyte ghosts exhibit the highest sensitivity to oxidative damaged and their sensitivity increases as a power function of the number of double bonds per fatty acid molecule. Light emission in caprine, equine and bovine erythrocyte ghosts was very low, t-butyl hydroperoxide concentration-dependent but changes in fatty acid composition were not observed. The main conclusion of this work is that a low unsaturation degree of fatty acids in erythrocyte ghosts of caprine, equine and bovine prevent the lipid peroxidation on those membranes when they are incubated with t-butyl hydroperoxide. 相似文献
992.
We report an unusual case of orbital cellulitis in a cat. Drainage via the pterygopalatine fossa and medical treatment were performed. Failure of resolution and loss of ocular structure and visual function with a poor prognosis led to enucleation. During surgery, plant material and purulent exudate were present in the orbit. Histopathology showed an intraocular foreign body of grass that had migrated through the sclera causing a suprachoroidal abscess with choroidal and retinal detachment. 相似文献
993.
Doménech N Bullido R Alvarez B Campos E Rodríguez-Carreño MP Gómez Del Moral M Alonso F Ezquerra A Domínguez J 《Veterinary research》2004,35(3):339-348
In this report, we describe the characterization of a novel activation antigen on porcine lymphocytes recognized by mAb 5A6/8. This antigen was detected on B and T cells 24 h after treatment with various stimuli. It was also found on alveolar macrophages, and at low levels on untreated monocytes. MAb 5A6/8 precipitated two bands of 45 and 50 kDa under non-reducing conditions, and of 22 and 28 kDa under reducing conditions. The cellular distribution, expression kinetics and/or molecular size of the 5A6/8 antigen differ from those of other known lymphocyte activation antigens. MAb 5A6/8 was able to inhibit lymphocyte proliferative responses driven by different stimuli, suggesting a role for this molecule in the events that lead to lymphocyte activation. 相似文献
994.
Evaluation of a segmented rectal probe and caudal epidural anesthesia for electroejaculation of bulls
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Etson CJ Waldner CL Barth AD 《The Canadian veterinary journal. La revue veterinaire canadienne》2004,45(3):235-240
Changes in concentrations of cortisol and progesterone in serial blood samples were used to quantify a stress response to different methods of electroejaculation in 10 Hereford bulls. Treatments included restraint (control), and electroejaculation using rectal probes with segmented electrodes or conventional nonsegmented electrodes, with or without lidocaine caudal epidural anesthesia. A subjective scoring system was used to assess behavioral responses to the different methods of electroejaculation. The increases in concentrations of serum cortisol and progesterone after electroejaculation were higher for all electroejaculation treatments than for restraint alone. The increases in serum progesterone concentrations were significantly lower at 5 and 20 minutes after electroejaculation with epidural anesthesia than with no anesthesia. However, the change in cortisol or progesterone concentrations did not differ after electroejaculation when comparing the conventional probe or a segmented probe at any time during the study. Subjective scoring showed no differences among electroejaculation methods. Use of epidural anesthesia was beneficial in reducing progesterone, one indicator of an endocrine stress response to electroejaculation. 相似文献
995.
Effect of early enteral nutrition on intestinal permeability, intestinal protein loss, and outcome in dogs with severe parvoviral enteritis 总被引:3,自引:0,他引:3
Mohr AJ Leisewitz AL Jacobson LS Steiner JM Ruaux CG Williams DA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):791-798
A randomized, controlled clinical trial investigated the effect of early enteral nutrition (EN) on intestinal permeability, intestinal protein loss, and outcome in parvoviral enteritis. Dogs were randomized into 2 groups: 15 dogs received no food until vomiting had ceased for 12 hours (mean 50 hours after admission; NPO group), and 15 dogs received early EN by nasoesophageal tube from 12 hours after admission (EEN group). All other treatments were identical. Intestinal permeability was assessed by 6-hour urinary lactulose (L) and rhamnose (R) recoveries (%L, %R) and L/R recovery ratios. Intestinal protein loss was quantified by fecal alpha1-proteinase inhibitor concentrations (alpha1-PI). Median time to normalization of demeanor, appetite, vomiting, and diarrhea was 1 day shorter for the EEN group for each variable. Body weight increased insignificantly from admission in the NPO group (day 3: 2.5 +/- 2.8%; day 6: 4.3 +/- 2.3%; mean +/- SE), whereas the EEN group exhibited significant weight gain (day 3: 8.1 +/- 2.7%; day 6: 9.7 +/- 2.1%). Mean urinary %L was increased, %R reduced, and L/R recovery ratios increased compared to reference values throughout the study for both groups. Percent lactulose recovery decreased in the EEN group (admission: 22.6 +/- 8.0%; day 6: 17.9 +/- 2.3%) and increased in the NPO group (admission: 11.0 +/- 2.6%; day 6: 22.5 +/- 4.6%, P = .035). Fecal alpha1-PI was above reference values in both groups and declined progressively. No significant differences occurred for %R, L/R ratios, or alpha1-PI between groups. Thirteen NPO dogs and all EEN dogs survived (P = .48). The EEN group showed earlier clinical improvement and significant weight gain. The significantly decreased %L in the EEN versus NPO group might reflect improved gut barrier function, which could limit bacterial or endotoxin translocation. 相似文献
996.
Production and characterization of monoclonal antibodies against midgut of ixodid tick,Haemaphysalis longicornis 总被引:2,自引:0,他引:2
Nakajima M Kodama M Yanase H Iwanaga T Mulenga A Ohashi K Onuma M 《Veterinary parasitology》2003,115(4):355-363
There are concerted efforts toward development of tick vaccines to replace current chemical control strategies that have serious limitations [Parasitologia 32 (1990) 145; Infectious Disease Clinics of North America (1999) 209-226]. In this study, monoclonal antibodies (mAbs) specific to Haemaphysalis longicornis midgut proteins were produced and characterized. Eight antibody-secreting hybridomas were cloned and the mAbs typed as IgG1, IgG2a and IgG2b. On immunoblots, all mAbs reacted with a midgut protein band of about 76 kDa. All mAbs uniformly immunogold-stained the surface or epithelial layers of H. longicornis midgut and endosomes. Adult ticks (50%) that fed on an ascitic mouse producing the IgGs developed a red coloration and did not oviposit. As such, the 76 kDa protein that reacted with the mAbs could, therefore, be a potential candidate for tick vaccine development. 相似文献
997.
998.
999.
Ten gram-negative, pleomorphic, rod-shaped isolates from coryza-like, respiratory diseased laying and broiler chickens were identified as Ornithobacterium rhinotracheale. All O. rhinotracheale isolates showed typical biochemical and enzymatic characteristics. Also, all isolates showed hemagglutinating activity with glutaraldehyde-fixed erythrocytes. On the basis of this property, a rabbit-raised antiserum was produced for an isolate. All isolates were identified by antiserum by hemagglutination-inhibition tests. No cross-reactions were observed when O. rhinotracheale isolates were tested with Haemophilus paragallinarum antisera, and vice versa. Mild respiratory signs, including mild nasal discharge, slight rales, and sneezing, were observed in challenged chickens. At postmortem examination, multifocal pneumonia, airsacculitis, and foamy exudate in abdominal cavity were observed. Furthermore, because bacterial adherence is regarded as an essential step in the infection process, in vitro adherence of O. rhinotracheale isolates to chicken tracheal epithelial cells was tested. All isolates showed positive adherence. Obtained results indicate that O. rhinotracheale is a pathogenic agent present in the Mexican poultry. 相似文献
1000.
Costa LR Gill MS Williams J Johnson AJ Angel KL Mirza MH 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(3):217-219
An 11-month-old, beefmaster bull presented with anorexia and signs of respiratory disease. Physical examination, thoracic ultrasonography and radiography, and pleural fluid analysis indicated pericarditis and septic neutrophilic pleuropneumonia. Postmortem findings were abomasal adherence to the diaphragm, a fibrotic fistulous tract connecting the abomasum and pleural cavity, granulomatous abomasitis, granulomatous pericarditis, and fibrinonecrotic pleuritis. 相似文献