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Objective To evaluate standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals, as techniques for obtaining tissue for assessment of copper status. The techniques were evaluated with respect to ease of use and effect on the animal.
Procedure Twenty of 24 Thoroughbred mares and 21 of their foals were biopsied. The animals were part of a larger study of the effect of copper supplementation on copper status and the prevalence of developmental orthopaedic disease. Livers were also collected from unrelated horses and sampled to investigate the variability in the distribution of copper in liver tissue.
Result The biopsy technique caused no lasting effect on the mares, but there was an increased risk of viscus penetration associated with taking multiple biopsy cores. The use of ultrasonography to scan the target area for the liver identified four cases that were not appropriate candidates for liver biopsy, because of large intestine being located in the biopsy area. In the foals there were no serious postoperative adverse effects, nor was there any evidence of problems caused by the procedure when the abdomen was examined post-mortem at 5 months of age. In livers collected to investigate the variability of copper concentration, copper appeared to be relatively evenly distributed through the liver.
Conclusion Standing, percutaneous, ultrasound-guided, transthoracic liver biopsy in mares, and transabdominal, laparoscopically-guided, liver biopsy under general anaesthesia in foals are convenient procedures for obtaining liver tissue for assessing copper status in horses. The use of ultrasound to identify liver tissue is recommended, especially in older mares.  相似文献   
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Cytokines have been associated with the progression of congestive heart failure (CHF) in humans and may be implicated in the pathophysiology of myxomatous mitral valve disease (MMVD) in dogs. The aim of this study was to determine the serum concentrations of cytokines in dogs with MMVD. The study included 16 Cairn terriers with no or minimal mitral regurgitation (MR), 41 Cavalier King Charles Spaniels (CKCS) with different degrees of MR and 11 dogs of different breeds with CHF due to MMVD. Granulocyte-macrophage colony-stimulating factor, interferon-γ, interleukin (IL)-2, IL-6, IL-7, IL-8, IL-10, IL-15, IL-18, keratinocyte-derived chemokine, interferon-γ-induced protein and monocyte chemoattractant protein-1 (MCP-1) were measured using a canine-specific multiplex immunoassay. CHF dogs had significantly higher MCP-1 concentrations than dogs with no or minimal MR. Among the CKCS, IL-2 and IL-7 decreased with increasing left atrial size and IL-7 also decreased with increasing MR. IL-8 decreased with increasing left ventricular end-systolic internal dimensions. MCP-1 was increased in CHF dogs compared to healthy control dogs and IL-2, IL-7 and IL-8 decreased with increasing indices of disease severity. The results suggest a role for these cytokines in canine MMVD and CHF.  相似文献   
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Accelerator mass spectrometer dating of an assemblage of fibrous and leather footwear from Arnold Research Cave in central Missouri documents a long sequence of shoe construction by prehistoric Midwestern peoples, beginning perhaps as early as 8300 calendar years before the present (cal years B.P.). An earlier fibrous sandal form dates from 8325 to 7675 cal years B.P., and later fibrous or leather slip-ons span the period from 5575 to 1070 cal years B.P. The assemblage adds to a growing picture of the highly varied nature of prehistoric footwear production in the United States throughout the Holocene.  相似文献   
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A novel viral haemorrhagic septicaemia virus (VHSV) of genotype IV was isolated from wild lumpfish (Cyclopterus lumpus), brought to a land‐based farm in Iceland, to serve as broodfish. Two groups of lumpfish juveniles, kept in tanks in the same facility, got infected. The virus isolated was identified as VHSV by ELISA and real‐time RT‐PCR. Phylogenetic analysis, based on the glycoprotein (G) gene sequences, may indicate a novel subgroup of VHSV genotype IV. In controlled laboratory exposure studies with this new isolate, there was 3% survival in the I.P. injection challenged group while there was 90% survival in the immersion group. VHSV was not re‐isolated from fish challenged by immersion. In a cohabitation trial, lumpfish infected I.P. (shedders) were placed in tanks with naïve lumpfish as well as naïve Atlantic salmon (Salmo salar L.). 10% of the lumpfish shedders and 43%–50% of the cohabiting lumpfish survived after 4 weeks. 80%–92% of the Atlantic salmon survived, but no viral RNA was detected by real‐time RT‐PCR nor VHSV was isolated from Atlantic salmon. This is the first isolation of a notifiable virus in Iceland and the first report of VHSV of genotype IV in European waters.  相似文献   
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The normal habitat of the parasitic stages of Ascaridia galli is in the small intestine of poultry but the exact localization is poorly understood. Therefore, a histological study was conducted in order to localize the larvae during the early phase of infection. Six layer pullets seven-week old were infected orally with 20,000 embryonated A. galli eggs each, whereas four chickens were left as un-infected controls. At necropsy 3 days after infection the first half of jejunum/ileum was divided into two equally sized sections (J1 and J2). After taking samples for histology from the middle of J1 and J2 and the junction between these determined JX, the two sections were subjected to parasitological examination. A higher number of A. galli larvae were recovered from section J2 than J1 and the majority of larvae were recovered from the most profound layers. Based on histology 144 larvae were identified and their location was noted. The highest number of larvae was observed in the JX sample as compared to J1 and J2 (P<0.001). Most of them were located in the profound crypt zone of the mucosa (51%) as compared to the other zones (P<0.05). The number of larvae was higher in the lumen (63%) compared to the epithelium (32%) and lamina propria (5%) (P<0.001). A significantly higher number of eosinophils were found in lamina propria of the infected group compared to the control group (P<0.001). This experiment clearly showed that only few larvae had penetrated the epithelium and were positioned in the lamina propria at 3 days post infection. It was far more common that the larvae were localized within the epithelium or in the lumen of the crypts. It is therefore suggested that at least in this early phase "mucosal phase" is a more appropriate term to be used for the A. galli larval localization as compared to the term "histotrophic phase" currently used in many textbooks.  相似文献   
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Transgenic technology holds considerable promise to advance understanding in biomedical and agricultural systems with some believing that one day transgenic animals may directly contribute to farming and breeding practice. Nevertheless, applications in livestock have been restricted in part by the inefficiency of the technology. The recent development of lentivirus vectors for transgene delivery may overcome some of this limitation. This presentation describes these vectors, their advantages and limitations.  相似文献   
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