Assessment of protective efficacy of live and killed vaccines based on a non-encapsulated mutant of Streptococcus suis serotype 2.   总被引：4，自引：0，他引：4  

Henk J Wisselink  Norbert Stockhofe-Zurwieden  Luuk A T Hilgers  Hilde E Smith 《Veterinary microbiology》2002,84(1-2):155-168

The protective efficacy of a live and killed non-encapsulated isogenic mutant of Streptococcus suis serotype 2 was determined in pigs, and compared with the efficacy of the capsulated wild-type strain. SPF pigs were vaccinated twice intramuscularly at 4 and 7 weeks of age with a dose of 1 x 10(9) formalin-killed CFU of the wild-type (WT-BAC), formalin-killed non-encapsulated mutant (CM-BAC) or live non-encapsulated mutant (CM-LIVE) strain. After 2 weeks, vaccinated pigs and non-vaccinated controls were challenged intravenously with 1 x 10(7) CFU of the homologous, wild-type S. suis serotype 2 strain. Protection was evaluated by clinical, bacteriological, serological and post-mortem examinations. All pigs vaccinated with WT-BAC were completely protected against challenge with the homologous serotype. Pigs vaccinated with CM-BAC were partially protected. Although all pigs vaccinated with CM-BAC survived the challenge, four out of five pigs developed clinical signs of disease for several days. Compared to the WT-BAC and CM-BAC, the CM-LIVE vaccine was less protective. Two out of five pigs vaccinated with CM-LIVE died in the course of the experiment and all of them developed specific clinical signs of disease for several days. The protective efficacy of the vaccines could be associated with serum antibody titers. Antibody titers against cells of wild-type and non-encapsulated mutant strains as well as against muramidase-released proteins (MRP) were high in pigs vaccinated with WT-BAC and CM-BAC. Pigs vaccinated with CM-LIVE showed lower antibody titers. Antibody titers against purified capsular polysaccharides (CPS) of S. suis serotype 2 were only found in pigs vaccinated with WT-BAC. These findings indicate that CPS and other bacterial components of WT-BAC are probably essential for full protection against homologous challenge.  相似文献   

Nitrous oxide emissions from potato cropping under drip-fertigation in eastern Germany     

Benjamin Trost  Hilde Klauss  Annette Prochnow  Katrin Drastig 《Archives of Agronomy and Soil Science》2013,59(11):1519-1531

In this article, a drip-fertigation system was compared to a control without irrigation concerning the amount of nitrous oxide (N₂O) emissions under the climatic conditions of north-east Germany. The investigation was carried out at a field research station in the federal state of Brandenburg. The mean N₂O emissions under drip-fertigation were significantly higher than under non-irrigation. The higher N₂O emissions under drip-fertigation can be explained by a constantly higher water-filled pore space (WFPS). These higher values in WFPS were caused by the necessary nutrient supply in combination with additional water application in periods with frequent rainfall.  相似文献   

Feed intake and growth of Arctic charr, Salvelinus alpinus (L.), fed diets supplemented with oxytetracycline and squid extract     

H. Toften  & M. Jobling 《Aquaculture Nutrition》1997,3(4):255-259

This study examined the long-term effects of a potential feeding deterrent, oxytetracycline (OTC), and a putative feeding stimulant, squid extract, on feed intake, growth and dry matter (DM) digestibility in Arctic charr, Salvelinus alpinus (L.). Fish were fed one of four diets for 9 weeks: 1. commercial feed formulation (basic); 2. BM (basic plus 20 g kg⁻¹ OTC); 3. BMS (BM plus 10 g kg⁻¹ squid extract); 4. BS (basic plus 10 g kg⁻¹ squid extract). The feed intake of Arctic charr was not reduced by the addition of OTC to the basic feed, and addition of squid extract to the medicated feed did not enhance feed consumption. DM digestibility and growth tended to be reduced in groups of fish fed diets supplemented with the antibiotic (BM and BMS). This suggests that OTC may have interfered with nutrient digestion and absorption. OTC does not seem to be a feeding deterrent for Arctic charr, possibly indicating that the charr is a rather unselective feeder. Because the medicated feeds were readily accepted, there may be little to be gained by addition of feeding stimulants to these types of feeds for charr.  相似文献   

Pathological pigmentation in cardiac tissues of Atlantic salmon (Salmo salar L.) with cardiomyopathy syndrome     

Hilde AS Fagerland  Lars Austb?  Camilla Fritsvold  Marta Alarcon  Espen Rimstad  Knut Falk  Torunn Taksdal  Erling O Koppang 《Veterinary research》2013,44(1):107

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Retailer-driven agricultural restructuring—Australia, the UK and Norway in comparison   总被引：1，自引：0，他引：1  

Carol Richards  Hilde Bjørkhaug  Geoffrey Lawrence  Emmy Hickman 《Agriculture and Human Values》2013,30(2):235-245

In recent decades, the governance of food safety, food quality, on-farm environmental management and animal welfare has been shifting from the realm of ‘the government’ to that of the private sector. Corporate entities, especially the large supermarkets, have responded to neoliberal forms of governance and the resultant ‘hollowed-out’ state by instituting private standards for food, backed by processes of certification and policed through systems of third party auditing. Today’s food regime is one in which supermarkets impose ‘private standards’ along the food supply chain to ensure compliance with a range of food safety goals—often above and beyond those prescribed by government. By examining regulatory governance in Australia, Norway and the United Kingdom we highlight emerging trajectories of food governance. We argue that the imposition of the new private forms of monitoring and compliance continue the project of agricultural restructuring that began with government support for structural adjustment schemes in agriculture and that these are most evident in the UK and Australia where neoliberalism is an entrenched philosophy. However, despite Norway’s identity as a social democracy, we also identify neoliberal ‘creep’ into the system of food governance. Small-scale producers in all three nations are finding themselves increasingly subject to governance through private, market-based mechanisms that, to varying degrees, are dominated by major supermarket chains. The result is agricultural restructuring not through the traditional avenues of elected governments, but via non-elected market operatives.  相似文献   

SALMON AQUACULTURE: LARGER COMPANIES AND INCREASED PRODUCTION     

Frank Asche  Kristin H. Roll  Hilde N. Sandvold  Arne Sørvig  Dengjun Zhang 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):322-339

Salmon farming is among the most successful aquaculture industries with a production growth that is substantially higher than aggregate aquaculture production in recent decades. It is well known that innovations and productivity growth are the main sources for this development. In this article we look closer at two potentially important factors in production growth, development of farm size and company size directly through economies of scale and indirectly through capacity in R&D, innovation, sales and marketing. In Norway, production per license has increased from 26 tons in 1980 to 1,130 tons in 2010, suggesting a substantial intensification in the industry. In all five leading salmon producing countries, the degree of concentration has increased and the large firms have become bigger over time.  相似文献   

Magnetic resonance and computed tomography imaging of a carotid body tumor in a dog     

Kaatje Kromhout  Ingrid Gielen  Hilde EV De Cock  Kristof Van Dyck  Henri van Bree 《Acta veterinaria Scandinavica》2012,54(1):24

A 5-year-old castrated male Labrador Retriever was presented to a referring veterinarian for a swelling in the neck region. Based on the results of histopathology, a carotid body tumor, was diagnosed. The dog was referred to a medical imaging unit for further staging and follow up. This report describes the magnetic resonance (MR) and computed tomographic (CT) appearance of a carotid body tumor.  相似文献   

Canopy height measurements and non‐destructive biomass estimation of Lolium perenne swards using UAV imagery     

Irene Borra‐Serrano  Tom De Swaef  Hilde Muylle  David Nuyttens  Jürgen Vangeyte  Koen Mertens  Wouter Saeys  Ben Somers  Isabel Roldn‐Ruiz  Peter Lootens 《Grass and Forage Science》2019,74(3):356-369

In perennial ryegrass breeding programmes, dry‐matter yield (DMY) of individual plots is monitored destructively at the different cuts or derived from non‐destructive canopy height measurements using devices like rising plate meters (RPM). These approaches both have constraints. Destructive sampling implies low temporal resolution, restraining the study of dry‐matter accumulation rates, while RPM measurements are influenced by the canopy structure and limit intra‐field variability identification. We present a phenotyping methodology, based on the use of an affordable RGB camera mounted on an unmanned aerial vehicle (UAV), to monitor the spatial and temporal evolution of canopy height and to estimate DMY. Weekly flights were carried out from April to October above a field comprising a diverse set of accessions. To test the capacity of UAV imagery to estimate canopy height, 8 ground control points and 28 artificial height references were placed at different locations. Accurate flights with an RMSE as low as 0.94 cm were achieved. In addition, canopy height was recorded using an RPM and destructive biomass samples were collected. Different models (linear, multiple linear, principal components, partial least squares regression and random forest) were used to predict DMY, and their performance was evaluated. The best estimations were obtained by combining variables including canopy height, vegetation indices and environmental data in a multiple linear regression (R² = .81). All models built using UAV data obtained a lower RMSE than the one using RPM data. The approach presented is a possibility for breeders to incorporate new information in their selection process.  相似文献   

Abdominal fluid from a dog     

Fry MM  DeCock HE  Greeley MA  Vernau W 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2003,32(2):77-80

A 2-year-old intact female mixed-breed dog with a 1-month history of lethargy and anorexia was evaluated for abdominal distension and an abdominal mass. The dog's last heat cycle, her third, was 1 month prior to presentation, and no reproductive cycle abnormalities were noted at any time. Hematologic and serum biochemical abnormalities were consistent with hemorrhage and inflammation. Ultrasonographic examination confirmed a large midabdominal mass and a moderate amount of abdominal fluid. Cytologically, the fluid showed evidence of pyogranulomatous inflammation, hemorrhage, and mesothelial reactivity, as well as ciliated columnar cells and free cilia that were interpreted as likely of oviductal origin. The mass was removed surgically, and the histopathologic interpretation was oviductal hamartoma with marked stroma formation and acute hemorrhage. To the authors' knowledge, this is the first reported case of oviductal hamartoma in any species and the first reported case detailing the finding of ciliated columnar epithelial cells in the abdominal fluid of a dog. Ciliated columnar epithelial cells in abdominal fluid should be considered indicative of a likely underlying oviductal lesion.  相似文献   

Biologic behavior and prognostic factors for mast cell tumors of the canine muzzle: 24 cases (1990-2001)     

Gieger TL  Théon AP  Werner JA  McEntee MC  Rassnick KM  DeCock HE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(5):687-692

The medical records of 24 dogs with histologically confirmed mast cell tumors (MCT) of the muzzle were retrospectively evaluated to determine their biologic behavior and prognostic factors. Information on signalment, tumor grade and stage, treatment methods, and pattern of and time to failure and death was obtained from the medical record. Twenty-three dogs were treated with combinations of radiotherapy, surgery, and chemotherapy; 1 dog received no treatment. There were 2 Grade 1, 15 Grade 11, and 7 Grade III tumors. Tumors were stage 0 (n = 8), stage 1 (5), stage 2 (6), stage 3 (4), and stage 4 (1). Mean and median survival times of treated dogs were 36 and 30 months, respectively. Prognostic factors affecting survival time included tumor grade and presence of metastasis at diagnosis. Dogs with Grade I and II tumors survived longer than dogs with Grade III tumors. Variables, including sex, age, gross versus microscopic disease, and treatment type were not found to affect survival. Local control rate was 75% at 1 year and 50% at 3 years. Tumor grade was the only variable found to affect local control. Dogs with Grade I tumors had longer disease-free intervals than those with Grade II tumors, and dogs with Grade II tumors had longer disease-free intervals than dogs with Grade III tumors. Eight of 9 dogs dying of MCT had local or regional disease progression. Muzzle MCT a rebiologically aggressive tumors with higher regional metastatic rates than previously reported for MCT in other sites.  相似文献