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81.
Between 1995 and 1997 a neurological condition in pheasant poults from 24 sites in England and Scotland was investigated. Affected birds showed varying degrees of ataxia and incoordinated movements and, in severe cases, recumbency, but generally remained alert with their heads held upright. The condition characteristically affected poults from seven weeks of age and the incidence on any one site was low. No significant bacteria were isolated consistently from brain tissue. The condition was characterised histologically by a non-suppurative meningoencephalitis, in which lesions were found predominantly in the cerebellum in 61 of 81 samples examined (75.3 per cent). A non-suppurative myelitis was recorded in 16 of 20 spinal cords examined. No lesions were recorded in peripheral neural tissue and lesions were rare in other tissues. The condition appeared not to have been recorded previously in pheasants. A viral aetiology was suspected but Newcastle disease virus was not involved.  相似文献   
82.
为了研究日粮的蛋白质和纤维水平对仔猪生产性能和健康状况的互作,特选择96头35日龄的仔猪(体重为9.11±0.60kg),分32个栏饲养,每栏3头,分成4个日粮处理组,饲喂期21d。在设定的2×2因子处理中,4种日粮以大米、奶制品和大豆粕为基础配制,日粮蛋白质设两个水平(15.4%与19.4%,风干基),纤维也设两个水平[低水平纤维(LF)为含5.3%中性洗涤纤维,高水平纤维(HF)为含7.15%中性洗涤纤维,风干基]。高水平纤维日粮组在基础日粮中添加了40g/kg的小麦麸和20g/kg的甜菜浆。每周测定动物生产性能,试验第1天和最后一天收集粪样进行微生物学分析,并且按1(液态)到4(硬实)的评分体系对粪便进行评分。在试验最后1d,每栏选1头猪采集血液,分析急性期反应蛋白(acute-phase protein)和主要急性期反应蛋白(major acute-phase prot)(即Pig-MAP)的含量,随后进行屠宰,对消化道(包括内容物)进行称重,并进行结肠组织学分析。饲喂高水平纤维日粮的仔猪具有较大的平均日增重(390g与457g,P≤0.001)和大肠重量(以占体重比例衡量为4.4%与5.4%,P≤0.05)。这与较高的短链脂肪酸浓度(尤其是乙酸和丁酸)、较少的大肠杆菌数量(每克粪便含7.77与6.86logcfu,P≤0.05)和较高乳酸杆菌与肠道细菌比(0.76与1.37,P≤0.05)是相符的。虽然日粮蛋白质水平没有改变猪的生产性能,但是20%的蛋白质水平提高(P≤0.05)了小肠(6.5与7.7)和大肠(3.8与4.3)的相对重量(占体重的百分比)。在大肠内,含20%蛋白质的日粮使仔猪杯状细胞数量增加(4.6/100与5.4/100μm;P≤0.05),并使肠上皮内淋巴细胞数量减少(1.8/100与1.3/100μm;P≤0.05)。在健康状况方面,提高日粮纤维水平所产生的效果与日粮中的蛋白质含量有关。在含16%蛋白质的日粮中增加纤维水平可降低粪便评分值、增加抗生素治疗次数,然而在?  相似文献   
83.
Canine monocytic ehrlichiosis (CME) caused by Ehrlichia canis is the most known canine tick-borne disease (TBD) spread throughout the world. Preventing tick bites is a priority to reduce the risk of TBDs and it was the aim of the present study to evaluate the efficacy of a combination of imidacloprid 10% and permethrin 50% (ImPer) (Advantix; Bayer AG, Germany) in a spot-on formulation to control CME under field conditions. On January-March 2005, 845 dogs from two kennels in southern Italy (kennels of Bari (KB)- and Ginosa (KG)), with a history of tick infestation were initially tested by serology and PCR assay for E. canis infection. Data on Leishmania infantum infection were also available from a previous study carried out on the same dog population. One hundred twenty-six dogs (14.9%) presented anti-E. canis antibodies with a relative prevalence of 15.6% (n=65 dogs in KB) and 14.2% (n=61 dogs in KG). Five hundred thirty-five animals found negative both for E. canis and L. infantum infections were enrolled in three groups (Group A--treated with ImPer once a month; Group B--treated every 2 weeks; and Group C--untreated control animals) and monitored for E. canis infection by serology and PCR in November 2005 (first follow-up) and in March 2006 (second follow-up). The E. canis infection was serologically revealed, at the first and/or second follow-up, in 26 animals from Group C in KB and KG (mean incidence density rate (IDR), 13.24%) while in none of the animals from Group A (KB and KG) and only in one animal from Group B (IDR 1.13%) in KG. The final protection efficacy of ImPer ranged from 95.57% to 100% in Groups B and A. At PCR only 15 dogs from KG were positive for Rickettsiales only at the first follow-up and at the sequence analysis two (both in Group C) revealed 100% homology with E. canis sequences while 13 with Anaplasma platys. Four out of 13 A. platys PCR-positive dogs were also seropositive for E. canis at one or both follow-ups. ImPer, by virtue of its repellent and acaricidal activity against ticks, has been shown to be efficacious to prevent E. canis infection in treated dogs living under natural conditions in endemic areas.  相似文献   
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87.
Litter was collected from four turkey farms (eight houses) with a history of fluoroquinolone (FQ) treatment failure, 10 adult broiler breeder chicken farms (43 houses) with one having a history of FQ treatment, and 30 broiler chicken farms (110 houses) with 24 having a history of FQ treatment. In the turkey litter, the percentage of nalidixic acid-resistant (at 100 microg/ml) coliforms/total number of coliforms ranged from 0.6% to 61.9%. Two of the four farms had houses containing coliforms resistant to the two FQs, enrofloxacin (1 microg/ml) and sarafloxacin (1 microg/ml). There was also multiple resistance to other antimicrobials on all four turkey farms (ampicillin, tetracycline, chloramphenicol, kanamycin). The level of total coliforms from the adult broiler breeder litter was low, and there were no nalidixic acid-resistant isolates from any of the 10 farms. In the broiler chickens, 7 of 91 houses with a history of FQ usage contained coliforms resistant to nalidixic acid; however, 2 of the 19 houses on farms with no history of FQ usage had nalidixic acid-resistant coliforms. All of the broiler farms with nalidixic acid-resistant isolates were also resistant to the FQ sarafloxacin, whereas only 3 of the 24 treatment history farms and 1 of the no-treatment history farms exhibited enrofloxacin-resistant coliforms in the litter.  相似文献   
88.
The central and regional organisation of the campaign to eradicate the CSF epidemic in the Netherlands in 1997/1998 is described. The main instruments used in the campaign were based on stamping-out and movement restrictions specified by the European Union. Additional instruments were used for the first time, namely, pre-emptive culling of contact and neighbouring farms, compartmentalisation of transport, monthly serological screening in established surveillance areas and supervised repopulation of all farms in the former surveillance zone. Two other measures, the killing of very young piglets and a breeding ban were introduced to reduce production in established surveillance zones. Several factors complicated the eradication campaign, for instance, the late detection of the first infection; artificial insemination as a source of infection; the organisation of pig farming in the Netherlands, with its highly concentrated production and dependence on the transport of stock from one unit to another; insufficient rendering capacity; decreasing sensitivity of clinical inspection; and extremely high costs.  相似文献   
89.
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   
90.
We retrospectively evaluated predictive prognostic factors in 73 cats with vaccine‐associated sarcoma given postsurgical curative (n = 46, most with clean margins) or coarse fractionated radiotherapy (n = 27, most with either macroscopic disease or dirty margins). The former animals displayed a median survival of 43 months and a median progression free interval (PFI) of 37 months, the latter reached a median survival of 24 months and a median PFI of 10 months. In cats undergoing coarse fractionated therapy, factors predictive of a better outcome included lack of visible mass (n = 10) as opposed to macroscopic disease (n = 17, survival: 30 versus 7 months, P = 0.025; PFI: 20 versus 4 months, P = 0.01), adjuvant chemotherapy for gross disease (n = 5/17, survival: 29 versus 5 months, P = 0.04) and a smaller number of surgeries preceding radiation therapy (coeff = 0.41, P = 0.03). The Ki67 index was not predictive for survival. We concluded that postsurgical curative and coarse fractionated radiotherapy are effective legitimate options for managing vaccine‐associated sarcomas.  相似文献   
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