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991.
The climate in the UK is changing, with a trend towards increased rainfall in the autumn and winter and warmer average temperatures throughout the year. There has also been a 4-week extension of the herbage growing season over the past 40 years. These changes may have implications for the epidemiology of sheep helminth parasites. Here, we describe production-limiting disease outbreaks caused by Haemonchus contortus, Nematodirus battus, Teladorsagia circumcincta and Fasciola hepatica in sheep flocks in south eastern Scotland. The occurrence and timing of these disease outbreaks could not have been predicted in this region highlighting changes in the epidemiology of helminth infections from the patterns historically described. These cases are used to introduce discussion regarding the potential effects of climate change on the epidemiology of helminth parasites and the implications for sheep farming in the UK.  相似文献   
992.
993.
994.
Despite the widespread prevalence of infection with Peste des petits ruminants virus (PPRV) in goats and sheep industry in Asia and sub-Saharan Africa, there have been few, if any, structured population-based studies examining the epidemiology of this infection in Tanzania. In this study, we investigated the seroprevalence, and risk factors, of Peste des petitis ruminants(PPR) in sheep and goat flocks from seven different geographical administration authorities (Ngorongoro, Monduli, Longido, Karatu, Mbulu, Siha and Simanjiro) located in Northern Tanzania. Serum samples from 657 and 892 sheep and goats, respectively, corresponding to 91 sheep/goat flocks and 43 villages were collected. Competitive enzyme linked immunosorbent assay (c-ELISA) was used to detect the presence of antibodies in the serum against PPRV. Chi-square analysis and multivariable logistic regression model were used to identify risk factors for PPRV seropositivity. Findings suggested that the sero-positive cases were significantly higher in goats than in sheep (49.5% versus 39.8%; P = 0.002). The overall seroprevalence of PPRV infection in small ruminants was 45.8%. Highest seroprevalence (42.6–88.02%) was observed in Mbulu, Siha, Longido, Ngorongoro districts, while antibodies less than 40% to none were found in serum from Monduli, Karatu and Simanjiro, respectively. These findings confirm natural transmission of PPRV under field condition for the first time in Tanzania. Results may be correlated with variations in the sheep and goat husbandry practices within different geographic localities, the uncontrolled movement of animals, the levels of natural immunity and the sharing of grazing field amongst agro and pastoralists.  相似文献   
995.
Streptococcus suis is an important swine pathogen and a zoonotic agent. Differences in virulence have been noted among the 33 described serotypes, serotype 2 being considered the most virulent. In this study, we aimed at assessing the serotype distribution and the production of virulence-associated markers by strains recovered from diseased pigs in the United States (U.S.). Results showed that among the 100 strains evaluated, serotype 3 (20% of the isolates) and serotype 2 (17%) were the most prevalent. We then investigated the presence in these isolates of the genes sly, epf and mrp, encoding the virulence-associated markers suilysin (SLY), extracellular factor (EF) and muramidase-released (MRP) protein, respectively. The effective production of the markers by the strains was also verified. Results showed that the presence of the gene did not always correlate with actual expression of the respective protein. In the case of MRP, this was due, in most cases, to frameshift mutations at the 5′ end of the gene resulting in premature stop codons. The most prevalent phenotypes among U.S. strains were MRP+EFSLY (40%) and MRPEFSLY+ (35%). Serotype distribution greatly differed from that reported in several European countries, as did the production of virulence markers, particularly for serotype 2. On the other hand, our results for the U.S. S. suis isolates are similar to those reported for Canadian strains, suggesting a common status in North America.  相似文献   
996.
The aim of this study was to estimate the relative diagnostic sensitivity and specificity of a polymerase chain reaction (PCR) assay in the serum of dogs with naturally occurring non-myelosuppressive canine monocytic ehrlichiosis (CME), and to investigate the association between PCR positivity and immunofluorescence antibody (IFA) titres for Ehrlichia canis. Serum samples obtained from 38 dogs with non-myelosuppressive CME and 12 healthy dogs were analyzed retrospectively. Each serum sample was analyzed in triplicate using an E. canis-specific nested PCR assay targeting a 389 bp sequence of the 16S rRNA gene. E. canis DNA was amplified in 24 of 38 (63.1%) affected dogs; all samples from healthy dogs were negative. A high level of agreement was found among the PCR replicates (P < 0.0001). Median IFA titre of the 24 PCR-positive dogs was significantly lower than that of the PCR-negative infected dogs (P = 0.0029), indicating that E. canis DNA may circulate prior to the development of a high antibody titre. Serum-based PCR analysis is suggested for the early diagnosis of CME when whole blood samples are not available.  相似文献   
997.
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   
998.
ObjectiveTo evaluate the influence of premedication with tramadol on xylazine–ketamine anaesthesia in young pigs.Study designProspective, randomized, blinded cross-over study.AnimalsTen young Niger hybrid pigs: mean weight 6.1 ± 0.6 kg.MethodsPigs were anaesthetized twice. Xylazine (2.5 mg kg?1), ketamine (25 mg kg?1) and atropine (0.04 mg kg?1) were administered by intramuscular (IM) injection, 5 minutes after either tramadol (5 mg kg?1)) (treatment XKT) or saline (treatment XKS). Time to loss of righting reflex (TLRR), duration of antinociception, duration of recumbency (DR) and recovery times (RCT) were recorded. Quality of induction of anaesthesia including ease of endotracheal intubation was assessed using a subjective ordinal rating score of 1 (worst) to 4 (best). Heart, pulse and respiratory rates, arterial oxygen saturations and rectal temperatures were determined over 60 minutes. Antinociception was assessed by the pigs’ response to artery forceps applied at the interdigital space. Data were compared with Student's t-test, Mann–Whitney's test or analysis of variance (anova) for repeated measures as appropriate and are presented as mean ± standard deviation.ResultsThe quality of anaesthetic induction was significantly better and duration of antinociception significantly longer (p < 0.05) in treatment XKT (3.1 ± 0.7 score; 43.7 ± 15.5 minutes) than in treatment XKS (2.8 ± 0.6 score; 32.0 ± 13.3 minutes). TLRR, DR and RCT did not differ significantly (p > 0.05) between treatment XKT (2.1 ± 0.8, 65.8 ± 17.0 and 13.2 ± 6.7 minutes) and treatment XKS (2.1 ± 1.3, 58.0 ± 14.8 and 10.3 ± 5.6 minutes). Physiological measurements did not differ between the treatments.Conclusion and clinical relevanceTramadol improved the quality of anaesthetic induction and increased the duration of antinociception in xylazine–ketamine anaesthetized young pigs without increasing duration of anaesthesia, nor causing additional depression of the physiological parameters measured.  相似文献   
999.
The objective of this retrospective study is to report and analyse the incidence of and risk factors for post-transplant malignant neoplasia (PTMN) in feline renal transplant recipients (cases, n  = 45) and compare incidence to a population of cats that did not receive a transplant (controls, n  = 79). Information from the medical records of cases regarding signalment, blood work and concomitant disease, post operative cyclosporine concentrations, survival time (ST), and whether PTMN developed, the type of PTMN, time to occurrence (TTO), and ST after diagnosis was gathered. PTMN occurred in 11 of 45 (24%) cases, of which, four were lymphoma. Median TTO of all PTMN was 1020 days. Median TTO of lymphoma was 454 days. Median ST after diagnosis of PTMN was 15 days. No risk factors were identified. Compared with control cats, cases had more than six times higher odds of developing PTMN compared with control cats ( P  < 0.01).  相似文献   
1000.
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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