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1.
George Rigos Alexandros Samartzis Morgane Henry Eleni Fountoulaki Efthimia Cotou John Sweetman Simon Davies Ioannis Nengas 《Aquaculture International》2010,18(6):1093-1104
The comparative effects of iron-supplemented levels on growth, tissue distribution, haematology and immunology of gilthead
sea bream, Sparus aurata (2 g) were investigated, using four organic (50, 100, 200, 300 mg ORG/kg diet) and one inorganic iron source (200 INOR mg/kg diet).
Fish were treated for 12 weeks with the experimental diets and maintained at a water temperature of 19–22°C. Growth (final
weight and specific growth rate), tissue distribution (spleen, liver and muscle), haematological parameters (red blood cells,
haematocrit, haemoglobin and mean corpuscular haemoglobin concentration) and non-specific immune indexes (respiratory burst
activity and antibacterial activity of serum) were analysed. No significant differences were found in growth and iron tissue
distribution among the tested groups. Red blood cell counting was statistically higher in fish given 50 ORG, 100 ORG, 200
ORG and 200 INOR feeds. However, haematocrit, haemoglobin and mean corpuscular haemoglobin concentration were not significantly
affected by increasing dietary iron. Fish receiving the 100 ORG diet had the best performance with respect to the respiratory
burst activity and significantly higher values for antibacterial activity of serum were obtained in fish fed with the 300
ORG diet. The present findings provided no clear evidence of the optimum iron concentration. However, there was adequate indication
that iron supplementation enhanced the performance of gilthead sea bream, mainly from a haematological and immunological point
of view. 相似文献
2.
通过饲喂使用一种独特的可持续生产的，有机认证的蛋白原料的无鱼粉日粮，海虾在一个生长季节可以增重高达23克。这一生产系统包括低饲养密度，自然手段调控微生物食物链，改善环境和动物福利。生产成本显著降低，生产的有机产品的价值提高。 相似文献
3.
The larviculture of Mediterranean marine fish species has focused on the production of Spurus auruta and Dicentrarchus labrar . European fry production of these species has increased from 12 million in 1987 to 28 million in 1989 and is expected to rise to nearly 40 million fry in 1990.
Within differing hatchery systems, larval survival has been improved through the use of commercially available w3-HUFA rich live food enrichment diets. This combined with the use of surface cleaning techniques has led to a standardization of larval rearing procedures enabling mass production of quality fry. Increased concern with larval hygiene has resulted in larger larval rearing batch production and regular sterilization periods in most European units.
Market pressure is stimulating established producers to diversify their species range and industrial quantities of Puntazzo puntuzzo , and Pagrus major are already being produced. Work has started on the larval culture of Dentex dentex, Pagrus pagrus and Seriola dumerilli . 相似文献
Within differing hatchery systems, larval survival has been improved through the use of commercially available w3-HUFA rich live food enrichment diets. This combined with the use of surface cleaning techniques has led to a standardization of larval rearing procedures enabling mass production of quality fry. Increased concern with larval hygiene has resulted in larger larval rearing batch production and regular sterilization periods in most European units.
Market pressure is stimulating established producers to diversify their species range and industrial quantities of Puntazzo puntuzzo , and Pagrus major are already being produced. Work has started on the larval culture of Dentex dentex, Pagrus pagrus and Seriola dumerilli . 相似文献
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5.
K Pittman A Pittman S Karlson T Cieplinska P Sourd K Redmond B Ravnøy E Sweetman 《Journal of fish diseases》2013,36(2):115-127
Mucous cell size and distribution were investigated in the skin of five salmon using a novel stereology‐based methodology: one (48 cm) fish to test 15 tissue treatment combinations on measures of cell area and density on the dorsolateral region and, using the most suitable treatment, we mapped mucous cell differences between body regions on four (52 cm) salmon, comprising a male and a female on each of two diets. The section site, decalcification, embedding medium and plane of sectioning all impacted significantly on mucous cell size, whereas mucous cell density is more robust. There were highly significant differences in both mucosal density and mean mucous cell size depending on body site: the dorsolateral skin of the four salmon had significantly denser (about 8% of skin area) and larger (mean about 160 μm2) mucous cells, whereas the lowest mean density (about 4%) and smallest mean area (115 μm2) were found on the head. We found that 100 random measurements may be sufficient to distinguish differences >7 μm2 in mean mucous cell areas. The results further suggest that salmon exhibit a dynamic repeatable pattern of mucous cell development influenced by sex, diet and possibly strain and season. 相似文献
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7.
Finney BP Gregory-Eaves I Sweetman J Douglas MS Smol JP 《Science (New York, N.Y.)》2000,290(5492):795-799
The effects of climate variability on Pacific salmon abundance are uncertain because historical records are short and are complicated by commercial harvesting and habitat alteration. We use lake sediment records of delta15N and biological indicators to reconstruct sockeye salmon abundance in the Bristol Bay and Kodiak Island regions of Alaska over the past 300 years. Marked shifts in populations occurred over decades during this period, and some pronounced changes appear to be related to climatic change. Variations in salmon returns due to climate or harvesting can have strong impacts on sockeye nursery lake productivity in systems where adult salmon carcasses are important nutrient sources. 相似文献
8.
S. A. Rider S. J. Davies A. N. Jha R. Clough J. W. Sweetman 《Journal of animal physiology and animal nutrition》2010,94(1):99-110
The bioavailability of trace elements in fishmeal diets is influenced by their chemical forms and dietary anti‐nutritional factors. In formulated fish feed, supplemented organically bound minerals may be more bioavailable than inorganic minerals. A 10‐week feeding trial was undertaken with rainbow trout (Oncorhynchus mykiss) to determine whether the inclusion of organically bound selenium (Se) and zinc (Zn) improved uptake and assimilation of these elements compared to commonly used inorganic forms. The three diets tested included a control diet, no added Zn or Se; an organic Se‐yeast and Zn‐proteinate supplemented diet; and an inorganic sodium selenite and Zn‐sulphate supplemented diet. The endpoints tested were apparent digestibility, whole body levels, tissue distribution and Se‐ and Zn‐dependent enzyme activities. Digestibility of residual Se in the basal diet was 54.2 ± 1.0% and supplemented Se‐yeast was significantly more digestible than selenite (p < 0.05). Digestibility of residual Zn was 21.9 ± 2.0% and no significant difference was found between the treatments (p = 0.89). Whole body Se was raised by both Se sources and to a greatest extent by Se‐yeast (p < 0.001). Zn‐sulphate, and to a lesser extent Zn‐proteinate, both raised whole body Zn (p < 0.05). Dietary Zn in the basal diet was found to be above requirements, yet Zn‐sulphate had a significantly greater retention than Zn‐proteinate in those tissues that responded to Zn supplementation. Se‐yeast significantly raised Se in all tissues to a greater extent than selenite, except in the pyloric caeca and liver where the greatest increases were by selenite. Only Se‐yeast elevated Se‐dependent thioredoxin reductase activity (p < 0.05) and neither forms of Se affected glutathione peroxidise activity (p = 0.059). Alkaline phosphatase and carboxypeptidase B were not affected by Zn supplementation (p = 0.51 and p = 0.88 respectively). In all aspects, Se‐yeast was found to be a highly bioavailable form of Se in comparison to selenite. Because of its superior bioavailability, organically bound Se would be a preferred Se source for supplementation of fishmeal trout diets than selenite. 相似文献
9.
Eleni Fountoulaki Henry Morgane George Rigos Vasilaki Antigoni Eleni Mente John Sweetman Ioannis Nengas 《Aquaculture Research》2010,41(9):e208-e216
This study aimed to investigate the effect of increased zinc dietary levels on the growth performance, feed utilization, immune status and induced wound healing in European sea bass (Dicentrarchus labrax). Fish weighing 10 g were fed five diets containing organic zinc at 30, 70, 110 and 150 mg kg?1 diet and one inorganic zinc source (zinc oxide) at 150 mg kg?1 diet for a period of 12 weeks. No significant (P>0.05) differences were found in the growth performance parameters (final weight, specific growth rate), immunological indices tested (respiratory burst activity in whole blood) and the wound‐healing process. Zinc accumulation in the skin, vertebrae and liver increased significantly (P<0.01) with increased dietary zinc levels but not in muscle. The highest zinc concentrations were obtained in skin tissue, followed by vertebrae, liver and muscle tissue. Using the concentration of zinc in skin as a response criterion, broken‐line analysis showed that the supplementation of 148 mg organic Zn kg?1 diet seemed to be the optimum dietary zinc supplementation level for sea bass juveniles. 相似文献
10.
水产养殖业面临的挑战之一是被看作世界渔业生产的净贡献者,而不是潜在食品级渔业资源的消费者。水产养殖业的发展需开发新的渔业和甲壳类动物饲养策略,如果可能的话,使用非食品级和可以本地获得的饲料原料。1替代性蛋白原料替代性蛋白原料的一个必要特性,是一定不能影响对动物 相似文献