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排序方式: 共有346条查询结果,搜索用时 15 毫秒
61.
Lam TJ Jansen J van den Borne BH Renes RJ Hogeveen H 《New Zealand veterinary journal》2011,59(1):8-15
The veterinary practitioner is one of the most important advisors for farmers in the field of udder health. He or she has the tools to improve udder health if farmers are motivated to do so. Many farmers think that udder health is important, but this does not always mean that management of mastitis is up to standard. Many veterinarians are of the opinion that they are unable to convince their clients of the possible profits to be gained from investing in management of mastitis. Something is required to bridge this gap. This article, based on data and experiences from The Netherlands, describes the communication issues that can be considered in order to improve the role of the veterinarian as advisor, to achieve better udder health. The outcome is beneficial for both farmers and veterinarians, the former for reasons of economics, welfare and ease of work; the latter because it creates extra, challenging work. It is concluded that the veterinary practitioner is in an ideal situation to advise and motivate farmers to improve udder health but, to do this, the means of communication need to take account of the different learning styles of farmers. The most important aspects of such communication are found to be a pro-active approach, personalisation of messages, providing a realistic frame of reference for the farmer, and use of the farmer's social environment. Importantly, all persons and organisations in a farmer's social environment should articulate the same message. 相似文献
62.
Ploegaert TC Tijhaar E Lam TJ Taverne-Thiele A van der Poel JJ van Arendonk JA Savelkoul HF Parmentier HK 《Veterinary immunology and immunopathology》2011,144(1-2):88-94
Innate immunity plays an important role in preventing (barrier function) or combating infection (effector function). An important humoral component of innate immunity is formed by natural antibodies (NAb). The objectives of this study were to determine presence, variation among cows and repeatability within cows over time of total NAb titers directed to the pathogen-associated molecular patterns lipopolysaccharide, lipoteichoic acid (LTA) and peptidoglycan, and titers of NAb directed to the glycoprotein keyhole limpet hemocyanin in milk and plasma of individual cows. Furthermore in milk the antibody isotypes IgG1, IgG2, IgM and IgA binding LTA were analyzed. Ten milk and blood samples were obtained from each of 20 clinically healthy dairy cows from first to seventh parity during a period of 3 weeks. Total NAb binding lipopolysaccharide, LTA, peptidoglycan, and keyhole limpet hemocyanin were detected in milk and plasma, with titers considerably higher in plasma than in milk. Total NAb titers showed significant variation among cows, and repeatability within cows over time (ranging from 0.60 to 0.93). Titers of NAb in milk and plasma were positively correlated (correlation ranging from 0.69 to 0.91). Natural antibodies in milk binding LTA were of all 4 isotypes tested, although IgG2 was on average only present at low titers. All 4 isotypes in milk binding LTA also showed variation among cows, and repeatability within cows over time (ranging from 0.84 to 0.92). We conclude that NAb can be measured in a consistent and repeatable manner in bovine milk and blood plasma. 相似文献
63.
Cai S Li J Wong MT Jiao P Fan H Liu D Liao M Jiang J Shi M Lam TT Ren T Leung FC 《Veterinary microbiology》2011,152(1-2):46-54
Complete genomes of four Newcastle disease virus (NDV) strains, isolated from ducks and wild birds in Guangdong province of China from 2003 to 2007, were sequenced and analyzed in this study. Pathogenicity tests in chicken embryos and chickens illustrate that D3 and R8 are lentogenic, and W4 and P4 are mesogenic strains. Phylogenetic analysis using all six genes provides a high resolution profile for genotype designation as genotype I for D3 and R8 strains and genotype VI for W4 and P4 strains. In addition, molecular dating based on different genes suggests that D3 and R8 diverged from their common ancestor at around 1998; W4 and P4 diverged from their common ancestor at around 1999. Subsequent selective pressure analysis displayed specific traits of genes evolution in all 4 strains since their divergence from the recent common ancestor. Furthermore, the geographic origins of 4 strains were deduced to be from Europe via two independent introduction events by phylogeographical analysis. This provides insights to the potential influence of waterfowl migration on NDV epidemiology. 相似文献
64.
Wisner AL Desin TS Lam PK Berberov E Mickael CS Townsend HG Potter AA Köster W 《Veterinary microbiology》2011,153(3-4):274-284
Several structural components of the type III secretion systems (T3SS) encoded by Salmonella pathogenicity island (SPI)-1 and SPI-2 are exposed to the host's immune system prior to/during the infection/invasion process, making them potential vaccine candidates. In this study we evaluated whether chickens vaccinated with SPI-2 T3SS components could mount a significant humoral immune response (as measured by serum IgG titres) and whether these antibodies could be transferred to progeny (as measured by egg yolk IgG titres), and whether vaccinates and progeny of vaccinates could be protected against challenge with SE. The results of our studies show that vaccinated chickens do produce high levels of SPI-2 T3SS specific serum IgG that they are able to transfer to their progeny. It was demonstrated that vaccinates and progeny of vaccinates had lower overall countable recovered Salmonella enterica subspecies enterica serovar Enteritidis (SE) per bird in most situations. 相似文献
65.
Takayoshi Miyabayashi BVS MS PhD Mark Smith BS RT MS † Yoshihiro Tsuruno BVSc 《Veterinary radiology & ultrasound》2000,41(4):308-312
Various magnetic resonance (MR) imaging techniques have been used to assess lumbar spinal abnormalities in people. Four, young adult, clinically normal dogs were used to compare images of the spinal cord acquired using conventional spin-echo and rapid acquisition relaxation-enhanced (RARE), commonly called fast spin-echo (FSE), magnetic resonance imaging techniques. Lateral myelograms were made as an anatomic control. The T2-weighted FSE technique was characterized by better image quality than the T2-weighted conventional spin-echo technique. The short acquisition time with the FSE technique allowed increases in the matrix size and number of excitations, thus improving resolution and signal-to-noise ratio. In canine lumbar spinal MR imaging, use of a FSE technique is recommended to reduce the overall time for imaging and to improve image quality. 相似文献
66.
Philip R. Woods DVM PhD Wm. Tod Drost DVM Cyril R. Clarke BVSc PhD Carolyn J. Rodebush RT 《Veterinary radiology & ultrasound》2000,41(1):85-88
Ten healthy horses were injected intravenously with 99mTc-MAG3 and the disappearance of radioactivity from the blood was measured. The total body clearance (Cl(B)) and elimination half-life (t1/2(beta)) were 7.9 +/- 1.5 ml/kg/minute and 32.8 +/- 4.1 minutes, respectively. The disappearance of 99mTc-MAG3 from the blood of 2 horses with compromised renal function was also measured. The data suggest that 99mTc-MAG3 is a useful and clinically applicable radiopharmaceutical for measurement of effective renal blood flow in the horse. 相似文献
67.
Keko Hori Maxima E. Flavier Shigenori Kuga Thi Bach Tuyet Lam Kenji Iiyama 《Journal of Wood Science》2000,46(5):401-404
The study focused on kapok [Ceiba pentandra (L.) Gaertn.] fruit as a biomass for effective utilization. Kapok fruits were harvested just before full maturation at the campus of University of the Philippines Los Banos and in southern Vietnam. The kapok fibers are utilized locally as fiberfill in pillows, quilts, and some soft toys. Kapok fiber was isolated and analyzed microscopically, and the physicochemical properties were determined by spectroscopic methods. Some tests were done to determine the effective utilization of kapok fiber. Microscopic analysis of the higher structure of kapok fiber gave quite different results from cotton fiber, which has a significantly homogeneous hollow tube shape and is composed of cellulose (35 % dry fiber), xylan (22%), and lignin (21.5%). Kapok fiber is characterized by having a high level of acetyl groups (13.0%). Usually cell walls of plants contain about 1%–2% of acetyl groups attached to noncellulosic polysaccharides. Kapok fiber is significantly hydrophobic and does not get wet with water. Thus, the absorptivity of oil was tested. The fiber selectively absorbed significant amounts of oil (40 g/g of fiber) from an oil suspension in freshwater and seawater. It is suggested that this fiber could be used to recover oil spilled in seawater. 相似文献
68.
Enhancement by interferon of chicken splenocyte natural killer cell activity against Marek's disease tumor cells 总被引:1,自引:0,他引:1
A non-immune natural killer-type cell population (NK) from 6-to 12-week old chickens was able to kill MSB-1 Marek's disease (MD) tumor cells in vitro; as measured by the 51Cr-release cytotoxicity assay. Removal of T cells, B cells, adherent cells, or any combination of the three populations of cells did not result in diminished levels of cytotoxicity of the remaining spleen cells against MSB-1 cells. The cytotoxicity of chicken NK cells could be rapidly augmented by polyinosinic-polycytidylic acid (poly I:C) and by the Cal 11914 strain of Newcastle disease virus (NDV), but not by the TCND strain of NDV which is not an interferon (IFN) inducer, indicating that IFN play a role in augmentation of the NK activity in chickens. 相似文献
69.
Mortality reports were studied for 181 shipments of live sheep from Western Australia to the Middle East and Singapore in 1985 and 1986. Samples of pelleted feed for 93 shipments were analysed for quality. Overall death rate in the 6.46 million sheep exported in the period of the study was 2.18%. In sheep bound for the Middle East, most of the deaths occurred during the voyage (overall rate 1.7%, range 0.4-4.4% per shipment), although substantial mortality was recorded during discharge (rate 0.4%, range 0.0-1.8%). There were few deaths during loading (rate 0.07%, range 0.0-0.8%). Deaths in sheep bound for Singapore were almost 10-fold lower than those sent to the Middle East. Several findings suggested that ship design and management may contribute to mortality. Death rates were invariably low on some ships and often high on others. Death rates were nearly always higher in enclosed decks than in open decks on 4 vessels, and point epidemics of mortality were observed in several shipments. Temperature and relative humidity measured on the ship's bridge were not closely related to daily death rate. Antibiotics estimated to cost $226,000 were used during 33 voyages in 1986 and were considered of dubious efficacy on shipboard mortality. Analysis of feed pellets used on ship showed that the quality of the diet was within the range set by draft national standards for pellets used in the live sheep export industry. 相似文献
70.
SE RIDGE JT HARKIN† ‡ RT BADMAN† AM MELLOR§ JWA LARSEN¶ 《Australian veterinary journal》1995,72(4):150-153
SUMMARY: Johne's disease was diagnosed in 10 alpacas ( Lama pacos ) in Australia between February 1993 and May 1994. Eight of the animals were between 12 and 24 months of age, one was a 6-year-old female, and one was a 4-year-old male. Five, including the 6-year-old and the 4-year-old alpacas, showed weight loss and diarrhoea before death or slaughter. The other cases showed no clinical signs of Johne's disease but 4 gave a positive result on faecal culture and one gave a positive result on testing with the caprine ACID assay and had acid-fast organisms in its faeces. At necropsy, all cases had grossly enlarged mesenteric lymph nodes. Johne's disease was diagnosed after histological examination of the lymph nodes with conventional culture and polymerase chain reaction testing of tissue samples. This report outlines the clinical, epidemiological, and pathological findings in these cases. 相似文献