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41.
OBJECTIVE: To determine whether concentrations of proinflammatory cytokines, acute-phase proteins, and cortisol differ at parturition among 3 categories of sows (noninoculated, clinically affected and nonaffected following intramammary inoculation with Escherichia coll). ANIMALS: 16 sows. PROCEDURE: Sows were allocated to inoculated (n = 12) or noninoculated (4) groups. Inoculated sows received intramammary administration of E coli (serotype O127) during the 24-hour period preceding parturition. Blood samples were collected from noninoculated and inoculated sows for 3 consecutive days within 3 to 11 days before farrowing and inoculation. Samples were also collected 0, 24, 48, 72, and 96 hours after farrowing and inoculation. Inoculated sows were further categorized as affected (4 sows) or nonaffected (8 sows) based on clinical signs of disease. Serum tumor necrosis factor (TNF)-alpha, plasma interleukin (IL)-6, and serum amyloid A (SAA) concentrations were measured by use of ELISA; serum haptoglobin concentration was assayed by use of a hemoglobin-binding method; and plasma cortisol concentration was determined by use of radioimmunoassay. RESULTS: Plasma or serum concentrations of TNF-alpha, IL-6, and SAA of both categories of inoculated sows were significantly increased by 24 hours after intramammary inoculation of E coli, compared with concentrations in noninoculated sows. Concentrations of serum TNF-alpha and plasma IL-6 were significantly higher in inoculated sows that developed clinical mastitis than in nonaffected inoculated sows. CONCLUSIONS AND CLINICAL RELEVANCE: Concentrations of TNF-alpha and IL-6 are promising markers for the identification of periparturient sows with subclinical coliform mastitis. Identification of such sows should help improve the health and survival of piglets.  相似文献   
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Journal of Plant Diseases and Protection - The potato late blight pathogen Phytophthora infestans was collected from a region of Eastern Estonia during a period of seven years (2001–07). In...  相似文献   
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Prion diseases such as scrapie in small ruminants, bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt-Jakob disease (CJD) in man, are fatal neurodegenerative disorders. These diseases result from the accumulation of misfolded conformers of the host-encoded prion protein (PrP) in the central nervous system. To date naturally-occurring PrP free animals have not been reported. Here we describe healthy non-transgenic animals, Norwegian Dairy Goats, lacking prion protein due to a nonsense mutation early in the gene. These animals are predicted to be resistant to prion disease and will be valuable for research and for production of prion-free products.  相似文献   
47.

Background

A high use-efficiency of fertilizer N remains essential to sustain high crop productivity with low environmental impact. However, little is known on the long-term lability of mineral fertilizer N.

Aims

To quantify crop uptake and leaching of 15N-labelled mineral fertilizer that has been retained in an agricultural soil for 25–30 years in crops with variable growing season.

Methods

A field plot received 15N-labelled mineral fertilizers over a period of 5 years and was then kept under arable cropping for 12 years. After relocation to 16 lysimeters, the topsoil grew set-aside grassland for the next 13 years. Then crop uptakes and leaching losses of 15N remaining in soil was tested over a 2-year period by either converting set-aside grass to production grassland, or by replacing it with spring barley (+/− autumn cover crop) or vegetation-free fallow. All treatments received unlabelled mineral N fertilizers.

Results

Crop uptake and leaching of 15N were generally highest in the first test year after termination of the set-aside. The leaching of residual 15N in soil declined in the order: vegetation-free soil (4.7%), spring barley (1.9%), spring barley + cover crop (0.7%) and production grassland (0.2%). Corresponding losses for the second leaching period were 2.7%, 0.9%, 0.4% and 0.06%. There was a fixed relationship between leaching losses of 15N and total N.

Conclusions

After residing in soil for 25–30 years, the lability of labelled mineral N fertilizer residues appeared slightly higher than the lability of bulk soil N. Autumn vegetation was crucial for reducing leaching losses.  相似文献   
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A novel insertion element belonging to the IS110 family was identified in Mycobacterium avium subsp. paratuberculosis. The IS element, ISMpa1, is 1500 bp and has one ORF encoding a putative transposase. Three copies of ISMpa1 were identified in the M. avium subsp. paratuberculosis genome. The element had inserted into the 3' end of the highly conserved mycobacterial genes prrB and a homologue of M. tuberculosis Rv1593c, and between a putative cytochrome p450 oxygenase and a putative hydrolase. The IS element was present in all (n = 11) M. avium subsp. paratuberculosis strains but not detected in most other mycobacterial species examined, including 10 M. avium subsp. avium isolates of human, avian and porcine origin. However two porcine isolates of M. avium subsp. avium and the reference strain IWGMT49 did harbour ISMpa1. These three strains belong to a previously described subgroup of M. avium subsp. avium based on IS1245 restriction fragment length polymorphism (RFLP) pattern and serovars. All of the M. avium subsp. paratuberculosis strains examined had an identical RFLP pattern when probed with sequences corresponding to the 5' end of ISMpa1, whereas a different pattern was seen in the positive M. avium subsp. avium strains. This novel IS element might be a useful tool in strain classification of M. avium subsp. avium and also for the identification of M. avium subsp. paratuberculosis when used in combination with IS900.  相似文献   
49.
Detection of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) by polymerase chain reaction (PCR) is often hampered by the lack of efficient methods for sample treatment. We report a protocol for analysis of faecal samples based on buoyant density centrifugation in Percoll and IS900 sequence capture PCR combined with a dot blot assay for detection of low-grade infection of M. paratuberculosis. Serial dilutions of M. paratuberculosis genomic DNA and M. paratuberculosis bacteria were used to assess the sensitivity of the method. The final evaluation was performed with spiked faecal samples, which also were analysed by culture. The presence of PCR inhibitory substances in processed faecal samples was evaluated by including a PCR internal control. By using buoyant density centrifugation, sequence capture PCR, and dot blot hybridisation, we achieved a sensitivity of 10(3)CFU (colony forming units)/g of faeces. The detection limit by culture was assessed to 10(2)CFU/g of faeces. We conclude that the described protocol is a fast and sensitive alternative to bacterial culture of faecal samples.  相似文献   
50.
Primary flexor enthesopathy is a recently recognized elbow disorder and should be considered in the differential diagnosis of elbow lameness. For treatment planning purposes, it is important to make a distinction between primary and concomitant forms of the disease. The purpose of this prospective study was to compare radiographic findings for dogs with primary flexor enthesopathy (n = 17), concomitant flexor enthesopathy (n = 24), elbow dysplasia (n = 13), and normal dogs (n = 7). All dogs underwent a complete radiographic examination and each radiographic image was evaluated for the presence or absence of following characteristics: irregular medial humeral epicondyle, spur and calcified body. Additionally, the presence or absence of other elbow disorders (medial coronoid process disease, osteochondritis dissecans, ununited anconeal process, incongruity, subtrochlear sclerosis, and osteoarthritis) was recorded. Radiographic characteristics of flexor enthesopathy were found in 86% of painful joints in the primary flexor enthesopathy group and in 100% of painful joints in the concomitant flexor enthesopathy group. Radiographic characteristics of flexor enthesopathy were not found in sound elbow and elbow dysplasia groups. Frequencies and details of individual radiographic characteristics did not differ between primary and concomitant flexor enthesopathy groups. Findings support the use of radiography as a first screening method for detection of flexor enthesopathy, but not as a technique for distinguishing primary vs. concomitant forms.  相似文献   
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