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31.
    
A 10-year-old neutered male Airedale Terrier was evaluated for inappetance, weight loss, and lameness. Multiple myeloma was diagnosed based on bone marrow plasmacytosis, multiple lytic bone lesions, and hyperglobulinemia with a clonal gammopathy on serum protein electrophoresis. Splenic plasmacytosis, and retinal lesions consistent with hyperviscosity syndrome also were found. Temporary responses to 2 different chemotherapy protocols (melphalan and prednisone, and cyclophosphamide and prednisone) were seen, with remission of clinical signs and a decrease in the biclonal gammopathy but no resolution of the splenic mass. Eventual return of clinical signs led to euthanasia at 175 days postdiagnosis. Necropsy examination confirmed multiple myeloma involving bone marrow and spleen, and glomerulonephritis. An immunoglobulin-A (IgA) gammopathy was demonstrated by immunoelectrophoresis; biclonality was ascertained by immunofixation electrophoresis. The clonal components consisted of intact Ig with a heavy chain of the a class and a light chain of undetermined class. To our knowledge, this is the first report of undimerized biclonal gammopathy in a dog caused by a single heavy chain class involving IgA.  相似文献   
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Udder-thigh dermatitis (UTD) is a common disease in dairy cattle. The aim of this study was to define UTD incidence, its risk factors and the involved pathogens. Of 74 respondents, 72 (97%) reported having had the disease. On those farms the incidence was 5.3 cases per 100 cow years. The odds ratio (OR) of UTD in primiparous compared to multiparous cows was 23.4 (95% CI 17.3-33.8). Compared to tied stalls, the ORs of UTD were 0.65 (95% CI 0.45-0.92) and 0.43 (95% CI 0.24-0.71) for free stalls and straw yards, respectively. Udder oedema was reported in 98.3% of cows with UTD. The most common bacteria isolated from affected skin were Fusobacterium spp. (12/14 cases). This study suggests that UTD management should focus on local treatment, reducing udder oedema and increasing exercise.  相似文献   
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This study presents a depletion study for sulfadiazine and trimethoprim in muscle plus skin of gilthead sea bream (Sparus aurata L.). N4‐acetyl‐sulfadiazine, the main metabolite of sulfadiazine (SDZ), was also examined. The fish were held in seawater at a temperature of 24–26 °C. SDZ and trimethoprim (TMP) were administered orally with medicated feed for five consecutive days at daily doses of 25 mg SDZ and 5 mg TMP per kg of fish body weight per day. Two different diets, fish oil‐ and plant oil‐based diets, were investigated. Ten fish were sampled at each of the days 1, 3, 5, 6, 8, 9, 10, and 12 after the start of veterinary medicine administration. However for the calculation of the withdrawal periods, sampling day 1 was set as 24 h after the last dose of the treatment. Fish samples were analyzed for SDZ, TMP, and acetyl‐sulfadiazine (AcSDZ) residues by liquid chromatography–mass spectrometry. SDZ and TMP concentrations declined rapidly from muscle plus skin. Considering a maximum residue limit of 100 μg/kg for the total of sulfonamides and 50 μg/kg for TMP residues in fish muscle plus skin, the withdrawal periods of the premix trimethoprim‐sulfadiazine 50% were calculated as 5 and 6 days, at 24–26 °C, in fish oil (FO) and plant oil (PO) groups, respectively. The investigation of this work is important to protect consumers by controlling the undesirable residues in fish.  相似文献   
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Babesia divergens was cultivated in sheep erythrocytes in RPMI 1640 supplemented with 10% Fetal Calf Serum (FCS) or sheep serum. In vitro cultures in sheep red blood cells were initiated with human erythrocytes infected in vitro with B. divergens Rouen 1987 or with gerbil blood infected with several isolates from bovine origin. After the first subcultures on sheep erythrocytes, a ten-fold multiplication of the parasites was obtained within 48 h. Erythrocytes from three splenectomized sheep were infected in vitro with B. divergens; when parasitaemia reached 10%, the animals were inoculated with homologous parasitized erythrocytes. All sheep expressed hyperthermia with a peak between the 6th and the 9th day post-infection (p-i) and a transitory parasitaemia 10 days p-i. In vitro primary cultures were performed on two of these sheep, demonstrating the parasite persistence at very low parasitaemia in the infected animals. Splenectomized sheep can be used as a new model for B. divergens chronic infection.  相似文献   
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Genetic differentiation in aquatic systems is often driven by geographic distance (isolation by distance) due to the linear and hierarchical distribution of populations, but habitat fragmentation often exacerbates this effect by decreasing population connectivity, leading to isolation by resistance. Stronghold populations of the Kentucky Arrow Darter (Etheostoma spilotum) in the South Fork Kentucky River system within the Daniel Boone National Forest of eastern Kentucky, USA have a high population structure not explained by distance alone. Higher than expected levels of genetic differentiation among proximate populations were hypothesized to be driven by land-use change, but this was not previously tested. Here we use a riverscape genetics approach to test for the effects of natural landscape features including slope, elevation and stream size, and anthropogenically altered habitat features, including specific conductance (conductivity), culverts and forest cover, on population connectivity and genetic diversity of E. spilotum. We found isolation of populations among all tributary systems and a strong, positive relationship between genetic and geographic distances as expected. However, high conductivity levels due to surface coal mining best explain the population structure observed. We also found signatures of low genetic diversity overall and indicators that culverts may limit upstream movements of E. spilotum. This study provides a novel fine-scale view of the effects of instream and landscape features on connectivity among, and genetic diversity within populations of an imperilled, small-bodied, benthic fish.  相似文献   
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There has been conflicting debate over many years regarding the trophic status ofTricholoma matsutake (Ito et Imai) Sing., and further investigations are necessary to better understandT. matsutake physiology, particularly carbon nutrition, during ectomycorrhizal symbiosis. For this purpose, we developed a technique to rapidly synthesizein vitro ectomycorrhizas betweenPinus densiflora Sieb. et Zucc. andT. matsutake on artificial substrate (vermiculite: perlite: peat: beech sawdust; 5:5:1:1.), without added sugar in the nutrient solution. Only 1 week was required before the first rudimentary Hartig net ‘palmetti’ could be observed in roots. Well-developed Hartig net structures appeared in taproots after 2 weeks and in lateral roots after 3 weeks. Such rapid root infection may be attributed to the quality of the substrate and the inoculum used. This research was supported by a grant from the Bio-oriented Technology Research Advancement Institution (BRAIN).  相似文献   
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An experiment was conducted to evaluate the effects of dietary composition on apparent digestibility coefficients of protein, fat and carbohydrate of gilthead sea bream. In addition α‐amylase and proteolytic activities were measured in the digestive tract of fish, held at 20±1°C. Six experimental diets were formulated containing approximately 40%, 45% and 50% protein, 11% and 21% fat and a starch level which fluctuated from 14% to 36%. Fish having an average weight of 100–130 g were used, fed at 1.5% of their body weight daily, and digestibility was measured using an indirect method. Enzyme activities were measured in the digestive tract of fish, fed diets containing a combination of 40%, 50% protein with 11%, 21% fat at 0.5, 5, 10, 24 h after a single meal. Starch digestibility was reduced with its level in the diet. It also negatively affected fat digestibility as well as protein digestibility, the last only at the high fat level. Dietary fat level had a negative effect on starch and protein digestibility. Fat affected also strongly α‐amylase levels in the digestive tract, while its effect on protease activity was of smaller magnitude. These results indicate that digestive enzyme activities and nutrient digestibility values are affected by dietary composition, carbohydrates and fat indicating the strongest effect.  相似文献   
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The efficacy of hexaflumuron, a benzophenylurea insecticide, has been studied for the first time on a fungus-growing termite (Pseudacanthotermes spiniger Sjöstedt, Macrotermitinae). Results show that hexaflumuron could be useful in treating infestations of such pest species, which are of great economic importance in many tropical and equatorial countries. Foraging workers harvested and introduced treated food into the nest and subsequently contaminated the brood by trophallaxis. Hexaflumuron showed potent larvicidal activity. The compound did not appear to be rapidly degraded by the digestive enzymes of termite workers, nor by the symbiotic fungus Termitomyces eurhizus Heim growing on fungus combs. This chitin synthesis inhibitor did not act as a fungicide, since growth of the mycelium of this fungus was not inhibited in vitro. © 1998 Society of Chemical Industry  相似文献   
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The frequency, size, and insertion angle of primary branches are important determinants of wood quality and can be significantly influenced by silvicultural activities.  相似文献   
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