Increased demand has pushed extensive aquaculture towards intensively operated production systems, commonly resulting in eutrophic conditions and cyanobacterial blooms. This review summarizes those cyanobacterial secondary metabolites that can cause undesirable tastes and odors (odorous metabolites) or are biochemically active (bioactive metabolites) in marine and freshwater, extensive and intensive aquaculture systems. For the scope of this paper, biochemically active metabolites include (1) toxins that can cause mortality in aquaculture organisms or have the potential to harm consumers via accumulation in the product (hepatotoxins, cytotoxins, neurotoxins, dermatoxins, and brine shrimp/molluskal toxins), (2) metabolites that may degrade the nutritional status of aquaculture species (inhibitors of proteases and grazer deterrents) or (3) metabolites that have the potential to negatively affect the general health of aquaculture species or aquaculture laborers (dermatoxins, irritant toxins, hepatotoxins, cytotoxins). Suggestions are made as to future management practices in intensive and extensive aquaculture and the potential exposure pathways to aquaculture species and human consumers are identified. 相似文献
Labor costs of guppy growers and breeders are largely those of manual sorting (by strain, quality and gender) and counting fish. In most farms, female and male fish are grown together and sold either separately or together. Sorting fish according to gender is important for marketing as well as for breeding programs, so that a device for sorting and counting fish can potentially reduce production costs and improve quality.
A project aiming to develop sorting and counting technologies for ornamental fish growers included development and testing of image-processing algorithms for sorting guppy fish (Poecilia reticulata) by gender. The algorithms are derived from shape and color differences between female and male guppies. An algorithm for the determination of landmarks on fish contours was developed and found to be accurate in accordance with human judgment, enabling extraction of specific shape and color features of the tail and the body.
The algorithms were applied to three sets of images of guppies of the “Red-Blond” strain. Gender identification accuracy was approximately 90% using shape features, approximately 96% using color features and was slightly improved when both color and shape features were used.
Some of the components used are essential for future development of a computer vision based system for sorting and grading ornamental fish by strain and quality. 相似文献
AIM: To investigate the effects of exogenous L-carnitine on lipid metabolism in semi-starved rats fed on high fat diet. METHODS: The semi-starved rats were restricted half in calorie intake on high fat diet for 2 week. L-carnitine was supplied at dose of 250 mg/kg·bw. The changes of plasma carnitine concentration, urinary excretion of ketone body, serum lipase activity, muscle carnitine palmitoyl transferase activity, triglyceride secretion and clearance rate were measured. RESULTS: The results showed that the concentration of plasma free carnitine increased significantly in carnitine supplemented rats compared to normal and semi-starved rats.The activities of muscle carnitine palmitoyltransferase and serum lipase were significantly enhanced in carnitine supplemented rats. The triglyceride secretion rate (TGSR) was also improved remarkably by carnitine supplementation. Meanwhile, the urinary excretion of ketone body was reduced significantly in carnitine supplemented rats compared to semi-starved rats. CONCLUSION: It is concluded that carnitine supplementation can significantly increase the plasma concentration of free carnitine and accelerate the lipid metabolism in semi-starved rats fed on high fat diet. 相似文献
AIM:To investigate the effect of berberine on IL-1 or tumour necrosis factor (TNF) induced polymorphonuclear leucocyte(PMN)-endothelium adhesion and adhesion molecules.METHODS:Based on the model of human umbilical vein endothelial cell (HUVEC), this study adopted Rose Bengal Stain, cell ELISA, immunocyto-chemical techniques to investigate the effect of berberine on PMN-endothelium adhesion and the expression of cell adhesion molecules (CAMs).RESULTS:Berberine inhibited IL-1, TNF-induced HUVEC adhesion for PMN when pretreated HUVEC and antagonised IL-1, TNF-induced upregulation of ICAM-1 on HUVEC. Meanwhile, TNF-stimulated PMN adhesion for HUVEC and CD18 upexpression on PMN was diminished in the presence of berberine.CONCLUSION: Inhibite PMN-endothelium adhesion by downregulating the CAMs expression to inhibite PMN migration across endothelium is one of the mechanisms of antiinflammation of berberine. 相似文献