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51.
On the basis of meat inspection in an abattoir in the eastern part of Switzerland, the incidence of liverflukes in cattle was recorded weekly during one year. The prevalence was compared with surveys from the seventies and nineties. The average incidence of Dicrocoelium dendriticum infection did not change. Although the prevalence of Fasciola hepatica apparently slightly decreased, an actual decrease of liverflukes could not be demonstrated. 相似文献
52.
53.
Braun U 《Veterinary journal (London, England : 1997)》2003,166(2):112-124
Ultrasonography is an ideal diagnostic tool for investigating gastrointestinal disorders in cattle. It is performed on standing non-sedated cattle using a 3.5 MHz linear transducer. In animals with traumatic reticuloperitonitis, inflammatory fibrinous changes, and abscesses can be imaged; however, magnets and foreign bodies are difficult to visualize because of the gas content of the reticulum. Ultrasonography can be used to assess the size, position and contents of the abomasum. Percutaneous ultrasound-guided abomasocentesis can be performed to evaluate the nature and chemical composition of its contents. In left displacement of the abomasum, the abomasum is seen between the left abdominal wall and the rumen. It contains fluid ingesta ventrally and a gas cap of varying size dorsally. Occasionally, the abomasal folds are seen in the ingesta. In cattle with right displacement of the abomasum, the liver is displaced medially from the right abdominal wall by the abomasum, which has an ultrasonographic appearance similar to that described for left displacement. Motility and diameter of the intestine are the most important criteria for ultrasonographic assessment of ileus. However, the cause of the ileus is rarely determined using ultrasonography. In cases with ileus of the small intestine, there is at least one region of dilatation of the intestine and motility is reduced or absent. In cattle with caecal dilatation, the caecum can always be imaged from the right lateral abdominal wall. The wall of the caecum closest to the transducer appears as a thick, echogenic, semi-circular line. 相似文献
54.
Wijkstrom UN 《Veterinary research communications》2003,27(Z1):461-468
If real prices for fish remain at the levels they had attained by 1999, in the year 2050 demand for fish and shellfish as food could be of the order of 270 million tons (live weight equivalent) per year. If producers were able to supply these quantities consumption would rise by 176% over this 50-year period. To meet the demand supply would have to expand at the rate of 2.1% annually; but, a review of the pattern of population growth--and of historical patterns of increases in per capita consumption of fish--shows that annual growth in the volume of fish demanded is likely to be largest in the coming two decades, and then to taper off. Will producers be able to deliver? It is clear that wild marine stocks at present harvested by capture fishermen cannot support fisheries that would yield much more than 100 million tons per year and of this amount a significant proportion will continue to be used for fish meal and oil production. The question therefore narrows down to: can aquaculture, or non-traditional marine species, supply the required amounts? The historical context of supply is considerably different from that which has prevailed during the past 30 years. At that time the growing demand in OECD countries was met partly through imports of fish produced in the seas and lakes of developing countries. During coming decades the increased demand in developing countries must be met essentially through their own resources. In fact, in poor countries it seems unlikely that supply will respond to demand unless they experience economic growth. 相似文献
55.
56.
De Martino L Marfe G Consalvo MI Di Stefano C Pagnini U Sinibaldi-Salimei P 《Veterinary microbiology》2007,123(1-3):210-216
Viruses have evolved different strategies to interfere with apoptotic pathways in order to halt cellular responses to infection. One previous study showed that transient transfection of bovine herpesvirus type-1 (BHV-1) UL14 protein is efficient in protecting Madin Darby kidney (MDBK) and human chronic myelogenous leukemia (K562) cells from sorbitol-induced apoptosis. This protein corresponds to a putative protein of BHV-1, which shares aminoacid sequence with a part of the peptide-binding domain conserved in human heat shock protein (HSP70) family. The pBK-CMV-UL14 plasmid transfected MDBK cells treated with sorbitol did not show caspase-3 and caspase-9 activation with respect to non-transfected MDBK cells (UL14 negative). Furthermore, we report that the expression of the full length sequence of BHV-1 UL14 is evident after 7 h of infection of BHV-1 on MDBK cells which were then treated with sorbitol. These results indicate that UL14 gene product has important implications to enhance cell survival in response to apoptotic stimuli. 相似文献
57.
Leucocyte trafficking in afferent and efferent mammary lymph and the supramammary lymph node in cows was examined during 4 h after intramammary infusion of endotoxin from Escherichia coli. Total and differential leucocyte counts were measured in milk, blood and lymph. The proportions of CD4(+), CD8(+), major histocompatibility complex (MHC) class II(+) and IgM(+) lymphocytes were examined in the lymph and lymph node. At post-infusion hour (PIH) 4, the flow rates of both lymph fluids had increased approximately eightfold. Total leucocyte concentration increased in afferent lymph, but decreased in efferent lymph. Neutrophils increased in afferent lymph at PIH 2 and in efferent lymph and milk at PIH 4. The predominant cell type in afferent lymph shifted from lymphocyte to neutrophil while lymphocyte was still at PIH 4 the predominant type in efferent lymph. Among the lymphocytes, B cells were predominant in afferent lymph and lymph node at PIH 4 while T cells, mainly CD4(+) cells, were predominant in efferent lymph both at PIH 0 and PIH 4. The CD4 : CD8 ratio was higher in efferent lymph and the challenged lymph node than in afferent lymph and the control node, respectively. There was a significant difference in proportions of each lymphocyte subpopulation except for IgM(+) cells, between afferent and efferent lymph after infusion. According to the results, there was already during the first hours of the immune response, a non-random trafficking of neutrophils and lymphocyte subpopulations resulting in a changed distribution of cells in afferent and efferent lymph and a difference in lymphocyte reactivity between the two lymph fluids. 相似文献
58.
The principles of maedi-visna eradication programmes were applied to a field trial for the eradication of ovine pulmonary adenocarcinoma (OPA). In two maternal flocks the prevalence of gross and histological lesions in slaughtered animals was 18.3 per cent and 29.8 per cent, respectively. The lambing period was supervised for three consecutive years from 1999 to 2001, during which the lambs were taken away from their mothers at birth, deprived of maternal colostrum, and hand-reared away from other sheep. Over the three-year period, 322 hand-reared animals, mainly male lambs between 10 and 14 months old, were slaughtered; their lungs were examined grossly, 52.5 per cent of them were examined histologically, and 105 samples of caudal mediastinal lymph nodes were examined by PCR. No OPA tumours were detected in the slaughter specimens from the derived flock, but one lamb had histological lesions in one lung location; intrauterine transmission was ruled out in this case. No clinical OPA has subsequently been observed in the hand-reared flock. Bronchoalveolar lavage samples from the breeding stock were examined by PCR in order to rule out further subclinical cases of OPA. No Jaagsiekte retrovirus was detected in any of the 488 samples. 相似文献
59.
60.
S Burkhardt J Hentschke H Weiler B Ehlers A Ochs J Walter U Wittstatt R G?ltenboth 《Berliner und Münchener tier?rztliche Wochenschrift》1999,112(5):174-179
Herpesvirus infections which take a fatal turn on African elephants as well as on Asian elephants seem to occur increasingly not only in the USA but also in European stocks. The endotheliotropic herpesvirus causes a rapidly progressing and severe disease which makes any therapeutical effort unsuccessful and finally results in death of the animal, especially in young Asian elephants. As all attempts to culture the virus failed up to now, molecular biological procedures have to be used more often for diagnostical purpose together with the common methods of pathology, virology, and electronmicroscopical evaluation. This is a report on the case of 'KIBA', an eleven year old male elephant at the Zoological Garden Berlin, infected with the endotheliotropic elephants herpesvirus. 'KIBA' was born at the Zoo in Houston, Texas, and raised within his herd. Upon arriving in Berlin in November 1997 he adapted to the new premises and climate and new social circumstances without any problems. In June 1998 he already serviced three females of his new herd several times. In August 1998 he died after passing a peracute progression of the disease after residenting in Berlin for only 9 months. The dissection of the animal revealed some evidence on an agent damaging the endothelium. Major signs indicating this agent were bleedings in several serous membranes, mucosa and on the the right atrium, as well as other parts of the myocardium. Furthermore there have been ulcerations at various localisations of the whole digestive tract. Slightly basophilic intranuclear inclusion bodies have been found histologically in endothelial cells of different organ samples. An examination of altered organ-material by electronmicroscopy made some herpesvirus-like particles visible. A virological investigation first revealed evidence of giant cell formations with solitary basophilic intranuclear inclusion bodies in different cell cultures, however, without any distinct cytopathogenic effect. Supported by molecular biological procedures the infection of 'KIBA' could be verified as the elephants herpesvirus. By means of PCR and subsequent sequence analysis a DNA-sequence typical for the elephants herpesvirus could be obtained which showed an identity of 97% with the terminase sequence of the elephant herpesvirus described by American authors. The deduced amino acid-sequences were 100% identical. To the terminase of the human cytomegalovirus, the elephant sequence had an identity of 53% (similarity: 74%). Based on the cooperation of ILAT, Institute of Veterinary-Pathology/Free University Berlin, Robert-Koch-Institut Berlin, and Zoological Garden Berlin, the cause of 'KIBA's' death could be discovered immediately. Possible implications of this case especially on breeding and keeping elephants are discussed briefly. 相似文献