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991.
The induction of a quick onset of immunity against feline parvovirus (FPV), feline herpesvirus (FHV) and feline calicivirus (FCV) is critical both in young kittens after the decline of maternal antibodies and in cats at high risk of exposure. The onset of immunity for the core components was evaluated in 8–9 week old specific pathogen free kittens by challenge 1 week after vaccination with a combined modified live (FPV, FHV) and inactivated (FCV) vaccine. The protection obtained 1 week after vaccination was compared to that obtained when the challenge was performed 3–4 weeks after vaccination. The protocol consisted of a single injection for vaccination against FPV and two injections 4 weeks apart for FHV and FCV.At 1 week after vaccination, the kittens showed no FPV-induced clinical signs or leukopenia following challenge, and after FCV and FHV challenges the clinical score was significantly lower in vaccinated animals than in controls. Interestingly, the relative efficacy of the vaccination was comparable whether the animals were challenged 1 week or 3–4 weeks after vaccination, indicating that the onset of protection occurred within 7 days of vaccination. Following the 1-week challenge, excretion of FPV, FHV and FCV was significantly reduced in vaccinated cats compared to control kittens, confirming the onset of immunity within 7 days of vaccination.  相似文献   
992.
Nicarbazin is an anticoccidial drug, used mainly in birds, which can also be used in rabbits. It has been shown to produce several effects, such as inhibition of growth and feed efficiency in poultry. The aim of the present work was to determine whether nicarbazin alters intestinal absorption of sugar. Results obtained show that nicarbazin decreases D-galactose accumulation in the jejunal tissue and increases mucosal to serosal transepithelial fluxes of this sugar, in both cases in a dose-dependent way. Furthermore, nicarbazin seems not to modify the sugar diffusion across the intestinal epithelium. The drug also stimulates the sugar uptake in brush border and basolateral membrane vesicles. The results suggest that in rabbits nicarbazin increases sugar intestinal absorption mediated by carriers.  相似文献   
993.
The effect of exogenous hyaluronate on normal cartilage metabolism and interleukin-1 (IL-1)-induced cartilage matrix degradation was investigated in a bovine cartilage explant culture system. Addition of hyaluronate at a concentration of 1.5 mg/ml to cartilage culture explants consistently decreased normal proteoglycan release from the matrix to a value less than that found in control cultures. Addition of 1.5 mg of hyaluronate/ml to IL-1 stimulated cartilage culture systems reduced proteoglycan release from the matrix by 83 to 113%. The reduction in control and IL-1-stimulated proteoglycan degradation by hyaluronate had a concentration-dependent trend. Evaluation of alterations in protein (enzyme) release by IL-1-stimulated chondrocytes after introduction of hyaluronate was evaluated by use of sodium dodecyl sulfate agar gel electrophoresis of cartilage-conditioned media. The quantity or the molecular weight profile of IL-1-induced proteins did not differ after introduction of hyaluronate into the culture system. Results indicate that introduction of high molecular weight hyaluronate into cartilage culture systems results in a decrease in proteoglycan release from the matrix in control systems, as well as in cultures incubated with IL-1. Because IL-1-stimulated protein synthesis by chondrocytes remains unchanged after addition of exogenous hyaluronate, the mechanism of inhibition of matrix degradation does not appear to be interference with binding of IL-1 to chondrocytes or to be inhibition of the production of neutral metalloproteases, including stromelysin.  相似文献   
994.
Immune system dysfunction and immunoglobulin deficiency was diagnosed in a 2-year-old horse with disseminated lymphosarcoma. Prolonged (35 days) parenteral nutrition was delivered to support the horse during a period in which immune function studies could be performed. Correction of nutritional compromise by use of parenteral nutrition did not correct the immunoglobulin deficiency, and results of lymphocyte phenotype testing did not indicate abnormal proportions of leukocytes. Lymphoblast transformation studies were suggestive of a circulating immunosuppressive factor in the horse's serum. Normal cell function was detected when the cells were stimulated in precolostral equine serum.  相似文献   
995.
Although low plasma taurine concentrations have been associated with congestive cardiomyopathy in cats, the cause of taurine depletion in cats consuming adequate quantities of taurine is unknown. Taurine depletion and cardiovascular disease (cardiomyopathy and thromboembolism) developed unexpectedly in 3 of 6 healthy adult cats during a potassium-depletion study. Plasma taurine concentration decreased significantly (P less than 0.05) and rapidly over an 8-week period (from 98 to 36 nmol/ml) in 6 cats that consumed a potassium-deficient diet (0.20% potassium, dry matter basis) that was acidified with 0.8% ammonium chloride, despite containing dietary taurine concentrations (0.12% dry matter basis) in excess of amounts currently recommended. Taurine concentrations were significantly lower in cats fed the acidified diet than in 6 cats fed a potassium-deficient diet that was not acidified (36 nmol/ml vs 75 nmol/ml) after 8 weeks. In addition, plasma taurine concentrations did not decrease over a 6-month period in 8 cats that were fed a potassium-replete diet with acidifier. Plasma taurine concentrations were lowest in 3 cats that died of cardiovascular disease in the group receiving potassium-deficient, acidified diets. These data indicated an association between taurine and potassium balance in cats and suggested that development of taurine depletion and cardiovascular disease may be linked to concurrent potassium depletion.  相似文献   
996.
Red deer calves dying at 24 to 72 hours old were infected with cryptosporidia. The clinical signs were extreme depression and weakness, but they did not consistently have diarrhoea. One calf was severely uraemic, and evidence from subsequent cases suggested that cryptosporidium infection in very young red deer calves may result in terminal uraemia. The possibility of intrauterine infection is considered. The factors which could have predisposed to the outbreak of infection were investigated; the calves were deficient in vitamin E despite having received adequate colostrum.  相似文献   
997.
Any patient presenting for anesthesia and surgery who has a severe debilitating problem is at great risk for a prolonged recovery, renal failure, or hypotension. A stable hemodynamic state should be maintained. Fluid homeostasis should be ensured. Anesthetic induction techniques using narcotics and benzodiazepines are my preferred approach, with maintenance of anesthesia incorporating isoflurane, narcotics, or both or the use of regional anesthesia.  相似文献   
998.
999.
Reference strains for Haemophilus parasuis serovars 1 to 7 were examined for virulence by inoculation of guinea pigs. Guinea pig response to intraperitoneal inoculation was similar for the 7 reference strains. However, apparent differences in virulence were detected after intratracheal inoculation. Cells of the references strains for serovars 1 and 5 were most invasive, causing moribundity or death at higher doses and a persistent septicemia at lower doses. Haemophilus parasuis could be isolated from respiratory and systemic sites; purulent bronchopneumonia, pericarditis, and pleuritis were apparent in infected guinea pigs. Inoculation of cells of the reference strains for serovars 2 and 6 also resulted in bronchopneumonia and moribundity or death in some guinea pigs; however, reisolation of H parasuis and microscopic lesions at necropsy were less pronounced than those observed with serovars 1 and 5. Inoculation of cells of serovars 3, 4 and 7 induced only transient clinical signs and minimal evidence of H parasuis infection at necropsy. The data from intratracheal inoculation of guinea pigs are similar to data from other investigations in swine, indicating differences in the pathogenic potential of H parasuis strains. Thus, guinea pigs may be useful as a laboratory animal model for examining cellular factors associated with virulence and immunogenicity of H parasuis.  相似文献   
1000.
The objectives were (i) to evaluate the effect of temperament, determined by modified 2‐point chute exit and gait score, on artificial insemination (AI) pregnancy rates in beef heifers following fixed time AI and (ii) to determine the effect of temperament on cortisol, substance‐P, prolactin and progesterone at initiation of synchronization and at the time of AI. Angus beef heifers (n = 967) at eight locations were included in this study. At the initiation of synchronization (Day 0 = initiation of synchronization), all heifers received a body condition score (BCS), and temperament score (0 = calm; slow exit and walk or 1 = excitable; fast exit or jump or trot or run). Blood samples were collected from a sub‐population of heifers (n = 86) at both synchronization initiation and the time of AI to determine the differences in serum progesterone, cortisol, prolactin and substance‐P concentrations between temperament groups. Heifers were synchronized with 5‐day CO‐Synch+ controlled internal drug release (CIDR) protocol and were inseminated at 56 h after CIDR removal. Heifers were examined for pregnancy by ultrasound 70 days after AI to determine AI pregnancy. Controlling for synchronization treatment (p = 0.03), facility design (p = 0.05), and cattle handling facility design by temperament score interaction (p = 0.02), the AI pregnancy differed between heifers with excitable and calm temperament (51.9% vs 60.3%; p = 0.01). The alley‐way with acute bends and turns, and long straight alley‐way had lower AI pregnancy rate than did the semicircular alley‐way (53.5%, 56.3% and 67.0% respectively; p = 0.05). The serum hormone concentrations differed significantly between different types of cattle handling facility (p < 0.05). The cattle handling facility design by temperament group interactions significantly influenced progesterone (p = 0.01), cortisol (p = 0.01), prolactin (p = 0.02) and substance‐P (p = 0.04) both at the initiation of synchronization and at the time of AI. Inter‐ and intra‐rater agreement for temperament scoring were moderate and good (Kappa = 0.596 ± 0.07 and 0.797 ± 0.11) respectively. The predictive value for calm and pregnant to AI was 0.87, and excited and non‐pregnant to AI was 0.76. In conclusion, the modified 2‐point temperament scoring method can be used to identify heifers with excitable temperament. Heifers with excitable temperament had lower AI pregnancy. Further, cattle handling facility design influenced the temperament and AI pregnancy.  相似文献   
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