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The prevalences of Cryptosporidium parvum, rotavirus, bovine coronavirus (bcv), and enterotoxigenic Escherichia coli (E coli k99) were determined in diarrhoeic dairy calves aged one to 21 days on 71 dairy farms in western Switzerland during the winter of 2005 to 2006. Faecal samples from 147 untreated calves suffering from acute diarrhoea were analysed by standardised diagnostic methods, and the immunoglobulin status of each calf was evaluated. The prevalences of C parvum, rotavirus, bcv and E coli k99 were 55.0 per cent, 58.7 per cent, 7.8 per cent and 5.5 per cent, respectively. The proportions of herds positive for the respective pathogens among the herds with diarrhoeic calves were 41.7 per cent, 52.1 per cent, 2.1 per cent and 2.1 per cent. The immunoglobulin concentration in the serum of 90.5 per cent of the diarrhoeic calves was below 8 g/l.  相似文献   
23.
This contribution is part of a bachelor thesis, which reviews the literature about suitable bio-indicators for the current dormancy status of a (fruit) tree in the winter. This is part of an on-going chilling research project and evaluation of the three chilling models as to their suitability for fruit growing in temperate zone regions with cool winters. The aim is to provide information on the dormancy status of a tree for the application of cultivation techniques to overcome dormancy.  相似文献   
24.
Specific regions in the rat larynx exhibit cellular changes in response to inhaled xenobiotics. These regions include the base of the epiglottis, ventral pouch, and medial surfaces of the vocal processes of the arytenoid cartilages. 1 , 2 In order to collect information on the usefulness of trimming techniques, the influence of different vehicles, the impact of different application routes in toxicity studies, and differences between induced vs. spontaneous lesions, the data obtained from a large number of inhalation and non-inhalation studies performed in Wistar RCCHan(TM): Wist rats at Harlan Laboratories Ltd Switzerland, all evaluated or reviewed by the same pathologist, were compiled for a detailed review. The value of different trimming techniques was deemed to be greatest for transverse and sagittolongitudinal section techniques, as compared to horizontolongitudinally section techniques. The comparison of lesions encountered in control rats of inhalation studies treated with different vehicles did not reveal differences in the type, distribution pattern, incidence and/or severity of spontaneous lesions. The types of lesions were also independent of different application routes in non-inhalation studies compared to inhalation studies. The pattern of spontaneous lesions in the rodent larynx was determined by degenerative and inflammatory lesions starting most often in the submucosal glands by desiccated secretion followed by mineralization and local inflammation or were induced by impacted foreign bodies. Squamous metaplasia was recorded in the respiratory epithelium overlaying the ventral gland as a spontaneous lesion in male Wistar rats from inhalation studies with a maxim of 20.0% in an inhalation oncogenicity study. Induced metaplastic changes recorded in the larynx were reversible. Other induced lesions in inhalation studies consisted of submucosal edema, necrosis, inflammation and/or granuloma. Induced lesions in non-inhalation studies were found to be exclusively related to reflux laryngitis or food impaction. It is concluded, that in rodents induced lesions of the larynx differ in type, distribution pattern, severity and incidence from spontaneous lesions.  相似文献   
25.
Impaired insulin sensitivity is increasingly recognised in cats, but sequences of genes involved in insulin-signalling are largely undetermined in this species. In this study, extended feline mRNA sequences were determined for the adiponectin, glucose transporter-1 (GLUT1), GLUT4, peroxisome proliferative activated receptor-gamma1 (PPARgamma1), PPARgamma2, plasminogen activator inhibitor-1 (PAI-1), monocyte chemoattractant protein-1 (MCP-1) and insulin receptor genes. Conserved dog-specific primers identified from human-dog mRNA alignments were used to amplify feline cDNA in the polymerase chain reaction (PCR). The feline sequences determined by this method were used to design feline-specific primers suitable for real-time PCR for quantification of gene expression in insulin sensitive tissues of healthy cats. Partial sequences of feline mRNAs had 86-95% identity with dog and human genes. Expression of adiponectin, GLUT1, GLUT4, PPARgamma1, PPARgamma2, PAI-1 and insulin receptor mRNA was detected and quantified in subcutaneous and visceral fat and skeletal muscle, whereas MCP-1 mRNA was detected in adipose tissue but not in skeletal muscle. Further characterisation of genes related to glucose metabolism in cats will provide additional insights into insulin-signalling mechanisms in this species.  相似文献   
26.
Soil compaction affects physical soil condition, in particular aeration, soil strength, and water availability and has adverse effects on plant growth. Bulk density is the most frequently used indicator to describe the state of compaction of a soil. However, this parameter lacks a direct functional relationship with plant growth. Various indicators have been proposed to simultaneously characterize the state of compaction of agricultural soil and its suitability for plant growth. This paper examines and compares the critical limits for crop plant growth based on three of these indicators: packing density, least limiting water range, and S parameter (the latter is the slope of the soil water‐retention curve in the inflexion point). In a first step, we reviewed the literature for published optimum and limiting values of bulk density and found that these values were highly dependent on clay and silt content. Converting them into corresponding values of packing density (composite index of bulk density and clay content), a value of 1.70 was found to effectively distinguish between optimum and limiting soil conditions for plant growth. In a second step, the packing density of 59 soil horizons sampled in N Switzerland was compared with the least limiting water range and the S parameter of these soil horizons (both determined by means of pedotransfer functions taken from the literature). A linear relationship between the three parameters was found, which allowed for a comparison of the published critical limits for plant growth based on these parameters. The critical limits of the three indicators, which had been postulated independently of each other in the literature, were found to agree well with each other. This means that all of them could equally be used to describe the compaction state of a soil and its physical suitability for plant growth. However, the proposed critical limits of packing density, least limiting water range, and S parameter still need further validation by field studies relating plant growth to soil compaction.  相似文献   
27.
Background: Bluetongue virus serotype 8 (BTV‐8) has caused disease in domestic ruminants in several countries of northern Europe since 2006. In 2008 a mass‐vaccination program was launched in most affected countries using whole virus inactivated vaccines. Objective: To evaluate 2 inactivated vaccines (Bovilis BTV 8; BTVPUR AlSap8) for immunogenicity and safety against BTV‐8 in South American camelids (SAC) in a field trial. Animals: Forty‐two SAC (25 Alpacas, 17 Llamas) aged between 1 and 16 years. Methods: The animals were vaccinated twice at intervals of 21 days. They were observed clinically for adverse local, systemic, or both reactions throughout the trial. Blood samples collected on days 0, 14, 21, 43, and 156 after vaccination were tested for the presence of BTV‐8 virus by real time‐polymerase chain reaction and of specific antibodies by competitive ELISA and a serum neutralization test. Results: All vaccinated animals developed antibodies to BTV‐8 after the 2nd administration of the vaccine. No adverse effects were observed except for moderate local swellings at the injection site, which disappeared within 21 days. Slightly increased body temperatures were only observed in the first 2 days after vaccination. The BTV was not detected in any of the samples analyzed. Conclusions and Clinical Importance: The administration of the 2 inactivated commercial vaccines was safe and induced seroconversion against BTV‐8 in all vaccinated animals. The results of this study suggest that 2 doses injected 3 weeks apart is a suitable vaccination regimen for SAC.  相似文献   
28.
Glucagon-like peptide-1 (GLP-1) analogues and inhibitors of its degrading enzyme, dipeptidyl peptidase IV (DPPIV), are interesting therapy options in human diabetics because they increase insulin secretion and reduce postprandial glucagon secretion. Given the similar pathophysiology of human type 2 and feline diabetes mellitus, this study investigated whether the DPPIV inhibitor NVP-DPP728 reduces plasma glucagon levels in cats. Intravenous glucose tolerance tests (ivGTT; 0.5 g/kg glucose after 12 h fasting) and a meal response test (test meal of 50% of average daily food intake, offered after 24 h fasting) were performed in healthy experimental cats. NVP-DPP728 (0.5–2.5 mg/kg IV or SC) significantly reduced glucagon output in all tests and increased insulin output in the ivGTT. Follow-up studies will investigate the potential usefulness as therapy in diabetic cats.  相似文献   
29.
ABSTRACT: Single nucleotide polymorphisms (SNPs) in the genes for interleukin-4, -13 and interferon-gamma, and 21 additional SNPs which previously had been significantly associated with immune traits in the chicken, were genotyped in white and brown layer hens and analyzed for their association with helminth burden following natural infections. A nucleotide substitution located upstream of the promoter of the interferon-gamma gene was significantly associated with the log transformed number of Ascaridia galli in the brown layer line (genotype CC: 6.4 ± 1.0 worms; genotype CT: 11.7 ± 2.2 worms). Therefore, IFNG seems to be a promising candidate gene for further studies on helminth resistance in the chicken.  相似文献   
30.
Several strategies are known for sanitizing dairy herd problems caused by Staphylococcus (S.) aureus. They mostly consist of general management measures but specific decision-making at an individual animal level has not been described. A sanitation program in the form of a process chart developed by the Bern Clinic for Ruminants was undertaken in 10 dairy herds with this problem. In an affected herd the cows were divided into 3 groups: healthy, suspect, infected. Three milk samples (MS), taken at two-week intervals were cultivated. The cows were grouped according to the culture results. To measure the success of the sanitation program, the key figures ?theoretical tank somatic cell count? (target < 150,000 SCC/ml) and ?percentage of cows over limit? (limit: 150'00 SCC/ml, target < 20 %) were used. These were compared with the corresponding key figures from dairy herds, which were followed-up by the Bern Clinic for Ruminants (control herds). The problem herd sanitation program lasted between 2 and 21 months. A total of 1598 MS were analyzed, of which 241 (15 %) were S. aureus positive (15 %). At the end of the sanitation the key figures between problem herds and control herds were similar. The sanitation program has proved to be practical. The detection of S. aureus positive cows proved to be reliable and the udder health of the herd could be significantly improved.  相似文献   
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