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A topical preparation containing miconazole, polymyxin and prednisolone was shown to be more effective in the treatment of otitis externa in 167 dogs than 2 other ear preparations containing antibiotics, an antimycotic and a corticosteroid. With miconazole, polymyxin and prednisolone, the recurrence rate was 26.7% compared with 72.6% and 54.3% when the other products were used. The mean duration of treatment required to achieve resolution of clinical signs was 9.6 days, compared with 12.2 days and 13.0 days and no cases failed to respond to treatment, compared with 17.7% and 14.3%. Malassezia canis alone (71%) or in association with bacteria (18%) was recovered from 44 of 49 ears cultured.  相似文献   
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There is a growing interest in the adoption of conservation tillage systems [no-till (NT) and reduced tillage (RT)] as alternatives to conventional tillage (CT) systems. A 2-year study was conducted to investigate possible environmental consequences of three tillage systems on a 2.4-ha field located at Macdonald Research Farm, McGill University, Montreal. The soil was a sandy loam (0.5 m depth) underlain by a clay layer. Treatments consisted of a factorial combination of CT, RT, and NT with the presence or absence of crop residue. Soil NO3--N concentrations tended to be lower in RT than NT and CT tillage treatments. Denitrification and N2O emissions were similar among tillage systems. Contrary to the popular assumption that denitrification is limited to the uppermost soil layer (0–0.15 m), large rates of N2O production were measured in the subsurface (0.15–0.45 m) soil, suggesting that a significant portion of produced N2O may be missed if only soil surface gas flux measurements are made. The N2O mole fraction (N2O:N2O+N2) was higher in the drier season of 1999 under CT than in 2000, with the ratio occasionally exceeding 1.0 in some soil layers. Dissolved organic C concentrations remained high in all soil depths sampled, but were not affected by tillage system.  相似文献   
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G. Ladizinsky  A. Hamel 《Euphytica》1980,29(2):313-317
Summary The seed protein profile of pigeon pea (Cajanus cajan) appeared to be highly stable. The standard profile of this cultigen was found in 86 of the 90 accessions examined. Each of the Atylosia species, A. lineata, A. platycarpa, A. cajanifolia and A. scarabaeoides has its own profile but each band of the Atylosia species had a homologue in the standard profile of Cajanus or in one of its variants. This was taken as an indication for the polyphyletic origin of Cajanus from several Atylosia species. The appearance of specific Atylosia bands in some of the electrophoretic variants of Cajanus suggests that gene flow is still effective between pigeon pea and various Atylosia species. The poor solubility of the Atylosia seed protein in comparison to Cajanus indicates that domestication of Cajanus was coupled with increased solubility and perhaps a better nutritional value of this pulse as well.  相似文献   
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No-tillage systems contribute to physical, chemical and biological changes in the soil. The effects of different tillage practices and phosphorus (P) fertilization on soil microbial biomass, activity, and community structure were studied during the maize growing season in a maize–soybean rotation established for 18 years in eastern Canada. Soil samples were collected at two depths (0–10 and 10–20 cm) under mouldboard plow (MP) and no-till (NT) management and fertilized with 0, 17.5, and 35 kg P ha?1. Results show that the duration of the growing season had a greater effect on soil microbiota properties than soil tillage or P fertilization at both soil depths. Seasonal fluctuations in soil microbial biomass carbon (SMB-C) and nitrogen (SMB-N), in dehydrogenase and alkaline phosphomonoesterase activities, and in total phospholipids fatty acid (PLFA) level, were greater under NT than MP management. The PLFA biomarkers separated treatments primarily by sampling date and secondly by tillage management, but were not significantly affected by P fertilization. The abundance of arbuscular mycorrhizal fungi (AMF; C16:1ω5) and fungi (C18:2ω6,9) was lower under NT than MP at the 10–20-cm soil depth in July. Phosphorus fertilization increased soil microbial biomass phosphorus (SMB-P) and Mehlich-3 extractable P, but had a limited impact on the other soil properties. In conclusion, soil environmental factors and tillage had a greater effect on microorganisms (biomass and activity) and community structure than P fertilization.  相似文献   
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The suspension‐feeding sea cucumber Cucumaria frondosa is widely distributed in cold waters and is commercially exploited in the North Atlantic. While the species is considered to have potential for aquaculture, its feeding and reproductive biology differs markedly from that of currently cultivated sea cucumbers. Here, for the first time, the influence of food sources on the condition of C. frondosa was experimentally tested. Individuals were fed with either diatoms or fish eggs for 3 months. Specific growth rate (SGR), organ indices, fecundity, gonad maturity and profiles of lipids and fatty acids (FA) in tissues were compared among treatments and with sea cucumbers collected from the field. Individuals fed with fish eggs showed higher SGR and organ indices than all other treatments. The highest proportion of large oocytes was also found in gonad tubules of females from the fish egg treatment, although individuals fed with diatoms were the only ones in which spontaneous spawning occurred. Moreover, gonad and muscle tissues of sea cucumbers from the fish egg treatment presented the highest levels of lipids and essential FA. In contrast, non‐fed sea cucumbers showed negative SGR, relatively low female fecundity and low concentrations of lipids and FA in tissues. While the fish egg diet presented several obvious benefits, phytoplankton remains an important source of carotenoids, which are vital for vitellogenesis in echinoderms. This indicates that mixed diets rich in lipids, essential FA and carotenoids can be further investigated to optimize growth and reproductive output of this species in captivity.  相似文献   
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Various seed diets containing chlortetracycline were fed to large and small parrots to evaluate serum chlortetracycline concentrations. The substitution of dehulled sunflower seed for whole sunflower in the seed mix may have resulted in higher chlortetracycline concentrations in cockatoos and parrots. The serum chlortetracycline concentration achieved for all diets was less than the goal of 1 μg/mL, but the concentrations attained may be useful for therapy.  相似文献   
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