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T-cell responses are supposed to be the major immune reactions in broilers infected with Eimeria. The nature of such T-cell responses is influenced by the species of Eimeria involved, age of the host, amount of parasites and the preceding infection history. In young chicks the intestine is still developing in length while the lymphocyte populations in the gut develop and differentiate. In chicks infected at young age the immune response may be different in quality as compared to responses in adults. We investigated the (T-cell) immune responses of young broilers to a primary Eimeria acervulina infection in relation to the number of parasites used for infection. In our experiment we infected one-day-old broilers with a low (5 x 10(2) oocysts) and a high (5 x 10(4) oocysts) dose of E. acervulina. We used a newly developed species specific real-time PCR to quantify total amount of parasites in the duodenum as the number of oocysts in faeces may not be representative for the exposure of the gut immune system. We characterized T-cell subsets in the duodenum by means of FACS-analyses, lymphocyte proliferation assays with spleen lymphocytes and the mRNA profiles of different cytokines (TGF-beta2, -4, IFN-gamma, IL-2, -6, -8 and -18) in the duodenum by means of real-time PCR. From day 5 p.i. broilers with a high dose of E. acervulina had a significantly lower body weight than the control group. No increase in CD4(+) cells, but a strong increase in CD8(+) cells was observed at days 7 and 9 p.i. in the duodenum of broilers infected with a high dose E. acervulina. IL-8 mRNA responses were observed after infection with low and with high infection doses, but no IFN-gamma and TGF-beta mRNA responses were found in the duodenum. The specific proliferative T-cell responses to a low infectious dose were not significantly different as compared to the control group. In conclusion, based on the kinetics of observed responses a primary infection with a high dose of E. acervulina in one-day-old broilers seems to generate an immune response that shows a peak at the time of oocyst excretion, whereas the immune response to a low dose is less explicit.  相似文献   
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The canine prostate gland shares many morphological and functional similarities with the human prostate and dogs are the only other large mammals that commonly develop spontaneous prostate cancer. However, the incidence of prostate cancer is much lower in dogs and the precise cell of origin is not known. Dogs with prostate cancer usually present with advanced disease that does not respond to androgen deprivation therapy. Similar to humans, affected dogs often develop osteoblastic bone metastases in the pelvis and/or lumbar spine with associated pain and neurological deficits. Other clinical signs include weight loss, lethargy, and abnormal urination and/or defecation. Surgery, chemotherapy, and radiation have been used to treat dogs with prostate cancer, but success has been limited by the location and aggressive nature of the disease. It is evident that better methods of early detection and more effective therapies are needed for prostate cancer in dogs and advanced prostate carcinoma in men. Dogs with naturally-occurring prostate cancer are relevant models for the disease in humans and pre-clinical studies of new diagnostics and therapies in dogs may benefit both humans and dogs with prostate cancer.  相似文献   
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Cokeromyces recurvatus, a zygomycete, was isolated by fungal culture from the peritoneal fluid of a cat with jejunal perforation secondary to intestinal lymphosarcoma. This organism has not been recovered previously from a veterinary patient. The tissue form of C. recurvatus is morphologically similar to those of Coccidioides immitis and Paracoccidioides brasiliensis and may be misdiagnosed as 1 of these organisms on the basis of cytologic or histopathologic specimens, particularly in geographic regions where these organisms are not endemic.  相似文献   
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OBJECTIVE: To determine the pharmacokinetics of enrofloxacin in neonatal kittens and compare the pharmacokinetics of enrofloxacin in young and adult cats. ANIMALS: 7 adult cats and 111 kittens (2 to 8 weeks old). PROCEDURE: A single dose of 5 mg of enrofloxacin/kg was administered to adults (i.v.) and kittens (i.v., s.c., or p.o.). Plasma concentrations of enrofloxacin and its active metabolite, ciprofloxacin, were determined. RESULTS: The half-life of enrofloxacin administered i.v. in 2-, 6-, and 8-week-old kittens was significantly shorter and its elimination rate significantly greater than that detected in adults. The apparent volumes of distribution were lower at 2 to 4 weeks and greater at 6 to 8 weeks. This resulted in lower peak plasma concentration (Cmax) at 6 to 8 weeks; however, initial plasma concentration was within the therapeutic range after i.v. administration at all ages. Compared with i.v. administration, s.c. injection of enrofloxacin in 2-week-old kittens resulted in similar Cmax, half-life, clearance, and area under the curve values. Enrofloxacin administered via s.c. injection was well absorbed in 6- and 8-week-old kittens, but greater clearance and apparent volume of distribution resulted in lower plasma concentrations. Oral administration of enrofloxacin resulted in poor bioavailability. CONCLUSIONS AND CLINICAL RELEVANCE: In neonatal kittens, i.v. and s.c. administration of enrofloxacin provided an effective route of administration. Oral administration of enrofloxacin in kittens did not result in therapeutic drug concentrations. Doses may need to be increased to achieve therapeutic drug concentrations in 6- to 8-week-old kittens.  相似文献   
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A 17-month-old cat presented for frequent swallowing, occasional cough and stertor. Radiographic evaluation revealed a soft tissue mass at the level of the soft palate. Oral examination revealed a soft tissue mass within the soft palate. Surgical resection was performed. Histopathology was consistent with a large developmental cyst. Following surgical management the cat has remained clinically free of signs for 2 months.  相似文献   
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ObjectiveTo determine the intraoperative and early postoperative opioid requirement after ultrasound-guided sciatic and/or femoral nerve block or epidural anaesthesia in dogs undergoing tibial plateau levelling osteotomy (TPLO).Study designProspective, masked, pilot, randomized, clinical trial.AnimalsA total of 40 client-owned dogs undergoing TPLO.MethodsEach dog was randomly assigned to group SF (combined sciatic and femoral nerve block), group S (sciatic nerve block), group F (femoral nerve block) or group E (epidural anaesthesia). A total of 0.3 mL kg–1 of ropivacaine 0.5% was administered to each nerve or in the epidural space. Intraoperatively, fentanyl (2 μg kg–1) was administered intravenously when heart rate, mean arterial pressure or respiratory rate increased by >30% compared with baseline values. Postoperatively, a visual analogue scale (VAS) and a modified German version of the French pain scale (4AVet) were used to assess pain every 30 minutes for 150 minutes and again once the morning after surgery. Methadone (0.1 mg kg–1) was administered intravenously if the VAS was ≥ 4 cm [maximal value 10 cm; median (interquartile range)] or the composite pain score was ≥5 [maximal value 15; median (interquartile range)]. Significance was defined as p ≤ 0.05.ResultsGroups SF and E required less total intraoperative and early postoperative opioid doses compared with groups S and F (p = 0.031). No dogs in group SF had a block failure or required postoperative methadone. A reduced methadone requirement was found in group SF compared with all the other groups up to 150 minutes after recovery (p = 0.041).Conclusions and clinical relevanceCombined sciatic and femoral nerve block and epidural anaesthesia lead to less cumulative consumption of perioperative opioids than single nerve blockade. Sciatic or femoral nerve block alone might be insufficient to control nociception and early postoperative pain in dogs undergoing TPLO.  相似文献   
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The efficacy of thyroid hormone replacement therapy (THRT) as treatment for owner-directed aggression in client-owned dogs with borderline low thyroid hormone levels was evaluated by means of a 6-week-long, parallel design, double-blind placebo-controlled study. The designation of “borderline hypothyroid” was made if the dog's free normal thyroxine (T4) value was frankly low or in the bottom 20th percentile of the normal range and either total T4, total triiodothyronine (T3), or free T3 was frankly low or in the bottom 30th percentile of the normal range. The presence of thyroid autoantibodies also qualified a dog for enrollment. Owners recorded the number of aggressive episodes directed toward family members on a daily basis for 8 weeks (2-week baseline phase and 6-week study phase). Twenty-nine dogs completed the study; 14 in a treatment group and 15 in a placebo group. The median number of aggressive episodes per day decreased significantly from baseline in both treated and placebo group dogs in weeks 1-2, 3-4, 5-6, and week 6 (treatment, χ2 = 24.8, P < 0.001; placebo, χ2 = 20.2, P < 0.001), however the median frequency of aggression was significantly lower in the treatment group (1.21 episodes/day) than in the placebo group (1.71 episodes/day) during week 6 of the study (χ2 = 4.047, P = 0.044). Three thyroxine-treated dogs had borderline-low thyroid levels on the final day of the study (day 42). When aggression frequency was compared between the treatment and placebo groups after the removal of 3 thyroxine-treated dogs, the treatment group did not have a significantly lower aggression frequency than the placebo group during week 6 (Kruskal–Wallis statistic: χ2 = 3.035, n = 26, P = 0.08). The authors discuss the role of thyroid hormones in the regulation of aggression and other cognitive issues and provide rationale for using THRT in dogs exhibiting owner-directed aggression that also have low normal or baseline thyroid hormone levels.  相似文献   
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