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61.
Physical and biological variables affecting juvenile Pacific herring (Clupea pallasi) in Prince William Sound (PWS) from 1995 to 1998 were investigated as part of a multifaceted study of recruitment, the Sound Ecosystem Assessment (SEA) program. Though more herring larvae were retained in eastern PWS bays, ages‐0 and ‐1 herring used bays throughout PWS as nursery areas. Water transported into PWS from the Gulf of Alaska (GOA) contributed oceanic prey species to neritic habitats. Consequently, variations in local food availability resulted in different diets and growth rates of herring among bays. Summer food availability and possible interspecific competition for food in nursery areas affected the autumn nutritional status and juvenile whole body energy content (WBEC), which differed among bays. The WBEC of age‐0 herring in autumn was related to over‐winter survival. The limited amount of food consumption in winter was not sufficient to meet metabolic needs. The smallest age‐0 fish were most at risk of starvation in winter. Autumn WBEC of herring and winter water temperature were used to model over‐winter mortality of age‐0 herring. Differences in feeding and energetics among nursery areas indicated that habitat quality and age‐0 survival were varied among areas and years. These conditions were measured by temperature, zooplankton abundance, size of juvenile herring, diet energy, energy source (GOA vs. neritic zooplankton), WBEC, and within‐bay competition.  相似文献   
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Cowpea (Vigna unguiculata L. Walp.) and tomato (Lycopersicum esculentum L. Karst) are attacked by a wide range of insect pests worldwide. In many cases, pesticides are used to control the pests. In 2010 and 2011, we conducted field experiments to evaluate and compare the effectiveness of a biorational (Agroneem~) and conventional pesticide (imidacloprid or thiamethoxam) on insect pests of these crops. In the first year, two varieties of cowpea (Mississippi Silver and Pinkeye Purple Hull) and two of tomato (Mariana and German Johnson) were used; in the second year, the better performing of each group (Mississippi Silver and Mariana) were used for the study. A split-plot design with four replications in Year 1, and a randomized complete block design with six treatment combinations in Year 2. In the first year, both pesticide groups were applied following manufacturer's recommendation (10-14 d cycles); and in the second year, the application of the pesticides was driven by economic thresholds level (ETL) of insect pests. The most prevalent species of insects recorded in both crops were in the families: Chrysomelidae, Pentatomidae, Cicadellidae, Vespidae, Sarcophagidae, Thripidae and Sphingidae. In both years, the diversity of insects on cowpea was greater than on tomato and more insects were observed in the second year compared to the first, despite the absence of significant difference (P 〉 0.05) between varieties in the treated plots. The yield of cowpea and tomato was comparable in all sprayed plots.  相似文献   
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It is usually assumed that plant tissue responses to nutritional elements are due to specific genetic differences that may exist either between inbred or closely related species. Little Marvel (dwarf) and Alaska (normal) varieties of 14‐day old pea seedlings were treated with four different concentrations of Al‐containing nutrient solution (0.0mM, 0.2mM, 0.6mM and distilled H2O), prior to being exposed for 14 days to either DARK, LIGHT, or UV. Selected tissues (root tip, main root, main stem and proximal stem) were bioassayed for peroxidase and polyphenol oxidase enzyme activities, fresh wt vs. dry wt, water uptake and stem growth. The present study suggests that Little Marvel and Alaska pea tissue responds to high toxicity levels of Al by demonstrating an enhancement of enzymic activity. Tissue weight, growth and water uptake also show differential tissue specificity in both Little Marvel and Alaska tissue, in terms of Al toxicity response, given a particular external exposure.  相似文献   
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Lung development was studied in late prenatal, 1-, 7-, 14-, and 21-days postnatal and adult cats. Cats were born with a few alveoli, and the lungs appeared to have patches of primitive air spaces (saccules). The saccules of prenatal kittens were thick walled, very cellular, and lined by type II pneumocytes. Eosinophils were observed in the septum, intraepithelially, and in the alveolar space of growing cats. Secondary septa were flanked by a double capillary network and divided saccules into multiple shallow alveoli. Septation was irregular and time dependent and not completed by day 231 of postnatal life. Elastic fibers accumulated at the tip of the septa, seemingly playing an important role in alveolar formation. Type II pneumocytes were located at the base of the secondary septa in growing cats, thus strengthening secondary septa to withstand the stresses of respiration. Pores of Kohn were not observed in growing cats.  相似文献   
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Canine pyoderma     
Bacterial skin disease (or pyoderma) is a common canine disorder. It is usually associated with coagulase-positive staphylococci which multiply on skin and induce disease as a result of a number of poorly understood mechanisms. Pyoderma usually occurs as a result of another underlying disorder. Primary causes include hypersensitivity, ectoparasites and metabolic and immunological disorders. A detailed and systematic investigation is mandatory so that the underlying cause is discovered if possible. A number of cases are idiopathic. Pyodermas may be classified according to depth of infection as this affects the type and duration of therapy required and the prognosis. Deeper forms require more aggressive and prolonged therapy. Management of pyodermas depends on the identification and correction of the underlying cause along with adjunct therapy using systemic and topical antimicrobial agents. Idiopathic cases may require protracted or even lifelong therapy with such medicaments. Glucocorticoids are generally contraindicated in the management of pyoderma.  相似文献   
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OBJECTIVE: To determine the association between cancer chemotherapy and serum canine distemper virus (CDV), canine parvovirus (CPV), and rabies virus antibody titers in tumor-bearing dogs. DESIGN: Prospective study. ANIMALS: 21 client-owned dogs with various malignancies and 16 client-owned dogs with lymphoma. PROCEDURE: In study A, serum antibody titers were measured by use of hemagglutination inhibition (CPV titers) or serum neutralization (CDV titers) before and at least 1 month after initiation of chemotherapy. Baseline values were compared with values obtained from a control population of 122 healthy dogs seen for routine revaccination. Titers were considered protective at > or = 1:96 for CDV and > or = 1:80 for CPV. In study B, serum IgG titers were measured by use of immunofluorescent assay (CDV and CPV titers) and rapid fluorescent focus inhibition test (RFFIT, rabies titers) at baseline and again at weeks 5, 8, and 24 of a standard chemotherapy protocol for treatment of lymphoma. An IgG titer of > or = 1:50 was considered protective for CPV and CDV. An RFFIT titer of > or = 0.5 U/ml was considered protective for rabies virus. RESULTS: Significant changes were not detected in CDV, CPV, and rabies virus titers following chemotherapy in tumor-bearing dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that established immunity to CDV, CPV, and rabies virus from previous vaccination is not significantly compromised by standard chemotherapy used to treat tumor-bearing dogs.  相似文献   
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