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411.
The main reasons for culling adult rabbit does on two Spanish rabbit farms were investigated for a year. The most important conditions were mastitis (33.3 per cent), followed by subcutaneous abscesses (9.9 per cent) and pyometra (8.7 per cent). Staphylococcus aureus infections were the most severe problem, the organism being isolated from 69.2 per cent of infected animals. Pasteurella species were more prevalent in cases of pyometra and pneumonia. Two strains of S aureus were identified by using polymorphism of the coagulase gene as the criterion. One of these strains was responsible for the majority of the staphylococcal infections and was isolated from several pathological processes.  相似文献   
412.
Multicomponent nutraceuticals are becoming increasingly popular treatments or adjunctive therapies for osteoarthritis in veterinary medicine despite lack of evidence of efficacy for many products. The objective of this study was to evaluate the anti-inflammatory and antioxidant activities of a commercially available C-phycocyanin-based nutraceutical and select constituent ingredients in an in-vitro model of canine osteoarthritis. Normal canine articular chondrocytes were used in an in-vitro model of osteoarthritis. Inflammatory conditions were induced using interleukin-1β. The nutraceutical preparation as a whole, its individual constituents, as well as carprofen were evaluated at concentrations of 0 to 250 μg/mL for reduction of the following inflammatory mediators and indicators of catabolism of the extracellular matrix: prostaglandin E2 (PGE2), tumor necrosis factor-α (TFN-α), interleukin-6 (IL-6), metalloproteinase-3 (MMP-3), nitric oxide, and sulfated glycosaminoglycans (sGAGs). Validated, commercially available assay kits were used for quantitation of inflammatory mediators. The antioxidant capacities, as well as cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and lipoxygenase (LOX) inhibitory activities of the whole nutraceutical preparation and select constituents, were also assessed using validated commercially available assay kits. The antioxidant capacity of the nutraceutical and constituents was concentration-dependent. The nutraceutical and constituents appear to display anti-inflammatory activity primarily through the inhibition of COX-2. The nutraceutical displayed similar strength to carprofen in reducing TNF-α, IL-6, MMP-3, nitric oxide, and sGAGs at select concentration ranges. The C-phycocyanin (CPC)-based nutraceutical and constituents may be able to mediate 3 primary pathogenic mechanisms of osteoarthritis: inflammation, chondral degeneration, and oxidative stress in vitro. The nutraceutical may be clinically useful in veterinary medicine and its efficacy should be further investigated in vivo.  相似文献   
413.
This work investigates the suitability of (1)H NMR spectroscopy to identify the fate of some bioactive compounds in seafood submitted to several processing conditions and examines the possibility of using (1)H NMR spectroscopy profiling to classify such products. Perchloric acid extracts of cod white muscle from newly killed and (i) unprocessed, (ii) boiled, and (iii) fried fillets and from (iv) frozen fillets, (v) the frozen fillets after thawing, and (vi) their drip loss and from (vii) rehydrated cod klippfish (n = 5) were analyzed by 500 MHz (1)H NMR spectroscopy. It was possible to identify taurine, betaine, anserine, creatine, and trimethylamine oxide (TMAO) in all extracts examined, and frozen fish was recognizable by the presence of dimethylamine (DMA). None of the heating procedures seemed to induce the loss of bioactive compounds from the fillet, but freezing and thawing did: the compounds were lost in what is known as drip loss. About 80% of the samples were correctly classified using a probabilistic neural network procedure having as inputs the scores of the first 20 principal components of the principal component analysis of a selected region of the NMR spectra.  相似文献   
414.
Changes in vegetation and soil hydrological resources occur in southern Spain because of the presence of a pluviometric gradient from west (1100 mm year?1) to east (240 mm year?1). Five hillslopes under different rainfall regimes were selected along this gradient and studied over a 4-year period. The objectives of the work were to analyze variation in soil moisture, water availability for plants, and drying processes on the hillslopes, and relationships between these factors and the annual variability of vegetation cover. The results show that clay content is a key factor defining the limit of water availability in the soil (the wilting point). Significant differences between soil moisture/available water and vegetation cover were observed, defining a positive feedback process that varied in nature along the pluviometric gradient. The more arid the climatic conditions the weaker the feedback between water content and vegetation cover. These observations can be explained by the greater water requirements of plant species growing on the more humid hillslopes, resulting in a rapid uptake of available water and higher water stress. However, at the driest sites the vegetation species were better adapted to the lack of water and more independent of rainfall. Available water at these sites did not decrease, because the lower number of days with a water deficit resulted in water availability for plants over a longer period of time.  相似文献   
415.
白血病对全球的家禽和种禽来说,是一个非常严重的疾病.美国科宝公司为了净化该病,虽然花费了大量的人力、物力和财力,但效果也是非常可喜的,目前在白血病控制上已无问题.下面重点介绍美国科宝公司在种鸡白血病净化上的一些经验.  相似文献   
416.
Aquaculture continues to be the fastest growing animal production industry and this rate of expansion must continue if aquaculture is to satisfy global demand for fish products in the face of dwindling capture fisheries. The relationship between aquaculture and biodiversity is complex, with examples of positive and negative impacts having been reported. To enable this expansion while avoiding negative impacts from introductions of exotic species, the investigation of indigenous species becomes important and worthwhile.This paper establishes the background to development of new species for culture and describes the example of the Mexican silverside Menidia estor, which has for centuries been the principal species in an artesanal fishery in Lake Pátzcuaro, Mexico. The species is geographically isolated and is unique but is now endangered because of a range of factors including overfishing, environmental degradation and introduction of exotic species. Considerable advances have been made recently in developing a closed reproductive cycle, understanding feeding and small‐scale on‐growing technology for the species. Based on this, a Darwin Initiative programme was developed focused on technology transfer to implement small‐scale pilot on‐growing thus helping to conserve the species and to improve livelihoods. This has allowed successful pilot scale development of aquaculture for the species while at the same time addressing the objectives of the international Convention on Biodiversity.  相似文献   
417.
Our report shows the calcium ion diffusion process through the different parts of maize kernels (pericarp, endosperm, and germ) during the traditional nixtamalization process as a function of steeping time (t) 0–24 hr. The cooking step of the nixtamalization process used 3 kg of maize kernels in 6L of water and 2% calcium hydroxide (w/w). The cooking temperature was 92°C for 40 min. The calcium content of the samples was measured using atomic absorption spectroscopy. We found that the whole instant corn flour, pericarp, endosperm, and germ, had a nonlinear relationship to steeping time, showing a local maximum at 9 hr. Analysis of the different parts of the nixtamalized kernels showed that in short steeping times (0–5 hr) calcium diffusion took place mainly in the pericarp. Calcium diffusion in the endosperm and germ occurred gradually over longer steeping times. However, the physical state of the kernels (broken kernels) accelerated the diffusion process. Calcium diffusion occurred first in the pericarp, followed by the endosperm and germ. Immediately after cooking (t = 0 hr), we found a 1.148% calcium content in the pericarp, 0.007% in the germ, and 0.028% in the endosperm. After 24 hr of steeping, the calcium contents were 2.714% in the pericarp, 0.776% in the germ, and 0.181% in the endosperm. In another study, the calcium content in the endosperm was measured by first separating the 10% from the outermost, followed by another 10% from the next endosperm tissue, and concluding with the remaining 80%. Calcium ions were present mainly in the outermost layers of the endosperm. The damaged kernels steeped for more than 5 hr showed greater calcium concentrations than the undamaged counterparts.  相似文献   
418.
Dietary intervention may be a valuable strategy to optimize the intra-articular environment in young horses to prolong their performance career. To test the hypothesis that dietary supplementation of a Saccharomyces cerevisiae fermentation product would reduce markers of joint inflammation and increase markers of cartilage metabolism following a single inflammatory insult, Quarter Horse yearlings (mean ± SD; 9 ± 1.0 mo) were balanced by age, sex, body weight (BW), and farm of origin and randomly assigned to the following treatment groups: 1.25% BW/d (dry matter basis) custom-formulated concentrate only (CON; n = 9) or concentrate top-dressed with 21 g/d S. cerevisiae fermentation product (SCFP; n = 10) for 98 d. Horses had ad libitum access to Coastal bermudagrass hay. On day 84, one randomly selected radial carpal joint from each horse was injected with 0.5 ng lipopolysaccharide (LPS) solution. The remaining carpal joint was injected with sterile lactated Ringer’s solution as a contralateral control. Synovial fluid obtained before supplementation (day 0) and on day 84 at preinjection hour 0 and 6, 12, 24, 168, and 336 h postinjection was analyzed for prostaglandin E2 (PGE2), carboxypropeptide of type II collagen (CPII), and collagenase cleavage neopeptide (C2C) by commercial assays. Rectal temperature, heart rate, respiration rate, carpal surface temperature, and carpal circumference were recorded prior to each sample collection and for 24 h postinjection. Data were analyzed using linear models with repeated measures. From day 0 to 84, synovial C2C declined (P ≤ 0.01) and the CPII:C2C ratio increased (P ≤ 0.01) in all horses with no effect of diet. In response to intra-articular LPS, synovial PGE2 increased by hour 6 (P ≤ 0.01) and returned to baseline by hour 336; CPII increased by hour 12, remained elevated through hour 168 (P ≤ 0.01), and returned to baseline by hour 336; and C2C increased by hour 6 (P ≤ 0.01) but did not return to baseline through hour 336 (P ≤ 0.01). Post-intra-articular injection, PGE2 levels were lower in SCFP than CON horses (P = 0.01) regardless of injection type. Synovial CPII and the CPII:C2C ratio demonstrated stability during the LPS challenge in SCFP compared with CON horses (P ≤ 0.01). Clinical parameters were not influenced by diet but increased in response to repeated arthrocentesis (P ≤ 0.01). Dietary SCFP may favorably modulate intra-articular inflammation following an acute stressor and influence cartilage turnover in young horses.  相似文献   
419.
Previous studies on the ability of human neutrophils to synthesize cytokines and express MHC Class I and inducible Class II molecules have suggested a possible role of these cells as accessory or antigen presenting cells (APC). There is no information available to date concerning this aspect in ruminants. Therefore, as the first step of these investigations, we have studied the cell surface expression of MHC molecules on goat neutrophils. We show that goat neutrophils can be distinguished from eosinophils with monoclonal antibody (MoAb) ILA-24 which recognizes cattle monocytes and neutrophils. Goat neutrophils constitutively express MHC Class II molecules. However, cell surface expression of MHC Class I and Class II molecules is dramatically reduced on neutrophils purified by density gradient centrifugation in comparison to neutrophils obtained from whole blood after lysis of erythrocytes. Also, the level of expression of MHC Class I antigens is seasonal and donor-dependent and rapidly decreases after in vitro culture despite negligible necrosis and apoptosis of neutrophils. Although treatment with IFNgamma partially prevents the loss of MHC Class I molecules on neutrophils, it fails to induce MHC Class II antigens. Implications of these results for further studies on the potential role of neutrophils as APC are discussed.  相似文献   
420.
Current research on the development of new neuromuscular blocking agents is directed towards producing agents that have a rapid onset of action and predictable duration of action and recovery times, with minimal hemodynamic effects. For the veterinary practitioner, these newer agents should be considered when muscle relaxation is required for certain surgical procedures. Care must be taken to monitor paralyzed patients appropriately to ensure adequate ventilation and anesthetic depth. Vigilant monitoring should exist during the recovery period for the development of muscle weakness from residual blockade and the ability to reverse the effects of neuromuscular blockade. The use of neuromuscular blocking agents in veterinary patients should continue to increase as newer drugs and better monitoring techniques are developed.  相似文献   
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