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1.
An epidemiological study was conducted in Orne (France) on randomly selected dairy herds (42 herds including 1,924 cows and heifers, which were at least 15 months old). The aim was primarily to estimate the seroprevalence of Neospora caninum infection from two blood samples per cow, using an enzyme-linked immunosorbent assay (ELISA) for N. caninum (one positive result indicating infection). The second aim was to test the association between some individual and herd factors and N. caninum seropositivity with a logistic model including a random term effect. The prevalence was estimated at 5.6% (107 seropositive animals). At least 27 of the 42 herds had one seropositive cow or heifer. The intra-herd seroprevalence varied from 1.1 to 8% for 18 positive herds (66.7%). Dogs were present in 36 farms and 104 of the 107 seropositive animals were exposed to them. The factors associated with individual seropositivity were the presence of cats (OR = 0.17; P < 0.001), dogs (OR = 4.35; P = 0.02), rabbits and/or ducks (OR = 2.10; P = 0.04), long calving periods (12 months) (OR = 0.44; P = 0.007), tethered housing (OR = 2.50; P = 0.01), somatic cell counts (200-400 x 10(3) cells/mL) (OR = 0.24; P < 0.001) and pond water supply (OR = 2.43; P = 0.04). In conclusion, the animal and intra-herd seroprevalences were low in dairy cows from Normandy, France.  相似文献   
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Sows have been identified as a source of Campylobacter contamination in piglets. We carried out a one-year study, in 2008, at 53 farrow-to-finish farms in Brittany, France, to determine the proportion of sows excreting Campylobacter. We also determined the genotypes of the Campylobacter isolates. Moreover, Generalized Estimating Equations including repeated effects were used to assess the association between management practices and farm characteristics, and risk of Campylobacter shedding by sows. Per farm, 10 feces samples from sows were collected from selected sites (maternity, service area, gestation area) on the farms. Campylobacter isolates were identified by PCR and typed by PFGE. Campylobacter was detected in 25.1% of the 530 samples from sows, and 67% of the 53 pig farms had at least one positive sample (of 10 taken). All the Campylobacter isolates belonged to the Campylobacter coli species. They displayed a very high level of genetic diversity, also inside farms and few genotypes were common to several farms. Warmer months, large farms, and individual housing for sows were identified as risk indicators of Campylobacter shedding by sows. A short delay between sampling and treatment of the samples should be considered, to improve the detection of the bacterium in the feces samples.  相似文献   
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在食品安全方面,最重要的发现之一是冷链系统在食品运输中的发展。从那以后,HACCP的采用已经在食品生产业中成为另一项改革,而分子生物学的最新进展使得快速微生物学方法的发展和运用相对于传统的方法来说是一种改革。公众在与食品中细菌传播有关的风险因子方面的知识已得到提高,但对弯曲杆菌的了解仍然很少。在这种情况下,本文将讨论一些细菌诊断工具,细菌收获前后的控制措施和收获后处理方法的优化。  相似文献   
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It has been shown that Escherichia coli isolates from lesions of cellulitis belong to a limited number of clonal groups distinct from those of isolates found in the environment of these birds. In this study, different in vitro methods were used to evaluate adherence properties of E. coli isolates from cellulitis lesions and environments of high- and low-cellulitis prevalence broiler flocks. One hundred isolates were tested by hemagglutination. Adherence to frozen sections of chicken skin and binding to soluble fibronectin were examined for 40 of these 100 isolates by immunofluorescence and by immunocytofluorometry, respectively. Localization of bacterial adherence to skin tissues was confirmed by immunohistochemistry. It was demonstrated that O78:K80 isolates from cellulitis lesions adhered to skin sections to a much greater extent in deeper than in superficial tissue layers. A greater bacterial adherence following growth in TSB at 37 C was demonstrated for isolates from flocks with high prevalence of cellulitis than for isolates from flocks with low prevalence of cellulitis. MANOVA analysis results showed a significant difference between superficial and deep tissue layers only for one set of isolates from flocks with high prevalence of cellulitis. Hemagglutinating activity was variable among the O78:K80 isolates obtained from flocks with high prevalence of cellulitis. The results obtained for some O78:K80 isolates following growth in TSB suggest a role for type 1 fimbriae or F1 in adherence to skin sections. This was reinforced by the finding that adherence was inhibited by D-mannose. Poultry E. coli isolates that express F1 had no affinity for soluble fibronectin, although localization of the adherence in skin sections suggested a role for extracellular matrix components such as collagen and insoluble fibronectin.  相似文献   
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OBJECTIVE: To determine whether hematologic and serum biochemical values for blood samples obtained from cats via vascular access ports (VAP) are comparable to those for samples obtained by direct venipuncture. DESIGN: Prospective study. ANIMALS: 14 healthy cats. PROCEDURE: A VAP was surgically implanted in a jugular vein in each cat. Blood samples were obtained from the VAP and by direct venipuncture of the contralateral jugular vein 10 weeks after VAP placement. Results of hematologic and serum biochemical analyses were compared by use of a paired t-test. The Pvalue to reject the null hypothesis was adjusted to account for multiple comparisons by using the Bonferroni procedure in which the nominal P-to-reject value is divided by the number of comparisons (0.05/24 = 0.002). RESULTS: Paired samples (VAP and venipuncture) obtained 10 weeks after VAP placement were evaluated for each cat. Of the 24 measured analytes, only potassium, total protein, and albumin concentrations differed significantly (P< 0.001 for all 3) between VAP and venipuncture samples. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that samples obtained from VAP are suitable for routine hematologic monitoring of feline cancer patients. Sample hemolysis may account for a slight increase in potassium, total protein, and albumin concentrations obtained from VAP samples. However, the values of variables most critical for monitoring of patients receiving chemotherapy (ie, mature neutrophil and platelet counts) are comparable. If proper techniques are used, VAP may be used for administration of chemotherapy as well as for blood collection in cats undergoing cancer treatment.  相似文献   
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A 2.5‐year‐old ovariectomized female ferret developed multiple progressive linear and raised nodules on the skin. The first lesions occurred on the tail, which was then amputated. Over the following 3 years, additional lesions appeared in the vicinity of the scar and then further rostrally on the flanks and thorax. Histological and immunohistochemical investigation led to a diagnosis of multiple piloleiomyomas. The unique characteristics of this ferret disease are described and compared with those of multiple piloleiomyomas in humans and with those of other cutaneous smooth muscle cell tumours reported in the veterinary literature.  相似文献   
8.
Malignant lymphoma is a common malignancy in birds. Paraneoplastic syndromes, which are commonly observed in domestic animals, have not been reported in association with lymphoma in birds. Hypercalcemia and hyperglobulinemia were found on plasma chemistry in two Amazon parrots, which were presented with aspecific symptoms. In both cases radiography and ultrasound demonstrated signs of hepatomegaly, which proved to be due to malignant lymphoma on postmortem examination. The hypercalcemia was found to be most consistent with a paraneoplastic effect of the malignant lymphoma in these birds. The exact origin of the hyperglobulinemia remains unclear.  相似文献   
9.
A novel spot-on formulation combining fipronil, amitraz and (S)-methoprene (CERTIFECT?, Merial Limited, GA, USA) was evaluated in adult Beagle dogs in a study to determine its adulticidal efficacy against the dog flea (Ctenocephalides canis, Curtis, 1826). Sixteen dogs were randomly allocated to treatment groups: 8 dogs served as untreated controls, and 8 dogs were treated once. Treatment consisted of applying a new combination formulation to deliver at least 6.7mg fipronil/kg body weight (bw), 8.0mg amitraz/kg bw, and 6.0mg (S)-methoprene/kg bw. The combination was designed to enhance the efficacy against ticks of the original fipronil/(S)-methoprene combination. Each dog was infested with 100 adult unfed dog fleas within 24h prior to treatment and then at weekly intervals for 8 weeks after treatment. At 24h after treatment or after each subsequent infestation, each dog was combed thoroughly to remove live fleas to be counted. A single treatment with CERTIFECT provided excellent knock-down of fleas within 24h after treatment and controlled re-infestations for up to 7 weeks (efficacy ≥96.5%, p<0.05).  相似文献   
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