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One alternative to contribute to the reduction of the pressure on coral reef ecosystems brought about by an increasing demand for marine aquarium ornamentals is to improve and further develop the culture of desirable species for trade. Peppermint shrimp from the genus Lysmata are among the most intensively traded decapod in the trade and while several studies have been conducted to improve its culture, individuals obtained from culture facilities are generally paler than those collected from the wild. Because color is a fundamental component of the price tag on most marine ornamental live species, poorly colored animals command a lower price, reducing competitiveness. In this study, we evaluate the influence of tank background color (reflected light) on the morphological coloration change of Lysmata boggessi. In a 15‐d experiment, 30 individuals were exposed either to reflected‐red or white light and the relative change of coloration between initial and final moments was quantified with photography (RGB color model). At the end of the experimental period, shrimp exposed to red‐reflected light presented a more intense red coloration than those exposed to white‐reflected light. These results demonstrate that a simple change in background tank color can enhance shrimp external coloration. Such a cheap‐to‐implement procedure can support the culture of more colorful, hence more valuable ornamental shrimp that can compete with those captured from the wild.  相似文献   
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The prevalence and risk factors associated with leptospirosis were studied in veterinary students in Zaragoza. Sera were collected at the beginning and end of the academic year 1994 to 1995 and were tested by ELISA against a pool of Leptospira interrogans serovars bratislava, canicola, grippotyphosa, hardjo, icterohaemorrhagiae and pomona antigens. At the beginning of the study the prevalence was 8.14 per cent and at the end it was 11.4 per cent. The incidence of the disease during the study was 0.0394. Risk factors associated with leptospirosis included: taking the course specialising in food inspection and technology, on-farm work, contact with pets in general, and particularly carnivores, and contact with animal traders. The symptoms associated with the disease were myalgia and fever, and the treatment of the symptoms provided some protection.  相似文献   
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The effect of four sterol biosynthesis-inhibiting fungicides added to the pitching wort on the evolution of several organoleptic parameters during the primary fermentation of young lager beer was assessed. Pyrimidine (nuarimol and fenarimol) and triazole (myclobutanil and propiconazole) fungicides were individually supplied to the pitching wort to obtain a concentration of 1 mg/L. A marked influence in the fermentation rate was observed for the samples with propiconazole residues. From the fourth day onward, the fermentation prematurely ceased (stuck fermentation), and therefore, statistical significant differences were found in fermented extract, alcohol content, fermentable carbohydrates, pH, color, and total polyphenol and flavonoid contents of beer. Myclobutanil residues are only influenced in the total polyphenol and flavonoid contents, while differences in the analyzed parameters were not noticeable for the samples containing nuarimol and fenarimol residues in comparison with the blank sample.  相似文献   
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This paper describes a sensitive isocratic HPLC/ECD method developed for the determination of rosmarinic acid (RA) in plant material, animal feed, and pig plasma. The plasma sample preparation only includes protein precipitation and adjustment of the pH. The applicability of the method was tested on plasma samples of pigs that were exposed to a 91-day oral intake of RA via feed enriched by aerial parts of Prunella vulgaris. The plasma was directly analyzed using the method described as well as after enzymatic hydrolysis. When no hydrolysis step was included, RA and caffeic acid (CA) were quantified in the plasma. In hydrolyzed plasma samples, several other metabolites were determined, including dihydrocaffeic, ferulic, and dihydroferulic acid. The dual-channel coulometric detection employed, as an alternative to mass spectrometry, offers good selectivity and sensitivity owing to the electrochemical properties of the phenolic constituents.  相似文献   
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New Forests - Achieving successful outplanting of trees on increasingly harsher sites is a global concern. In Chile, for example, new Eucalyptus globulus plantations are being targeted to poorer,...  相似文献   
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Three Brazilian and 9 French agricultural fertilizers were compared with Conway mixture, as nutrient enrichment for supporting the growth of 16 marine algae. Fertilizers containing only nitrogen and phosphorus appeared to be suitable. However, a few algae grew better in all-nutrient-enriched Conway medium. Addition of chelators did not generate better growth. Matrix-free fertilizers were found more convenient in use. A table is given to show the cheapest and/or best nutrient enrichment for each algal strain tested.  相似文献   
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Heartworm disease caused by Dirofilaria immitis affects canine and feline hosts, with infections occasionally being reported in humans. Studies have shown that both dirofilarial antigens and those derived from its bacterial endosymbiont Wolbachia, interact with the host organism during canine, feline and human infections and participate in the development of the pathology and in the regulation of the host’s immune response. Both innate and acquired immune responses are observed and the development of the acquired response may depend on the host and, or on its parasitological status. This review aims at illustrating current research on the role of both D. immitis and Wolbachia, in the immunology and immunopathology of dirofilariosis.  相似文献   
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