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KUNIHIKO  KONNO  CHO  YOUNG-JE  TAKEYA  YOSHIOKA  PARK  SHINHO  NOBUO  SEKI 《Fisheries Science》2003,69(1):204-209
ABSTRACT:    Jumbo squid was very similar to Japanese common squid in terms of myofibrillar Ca2+-, Mg2+- and K+(EDTA)-ATPase activities. Myofibrils of jumbo squid were significantly stabilized upon addition of Ca2+ and destabilized by increasing KCl concentration for heating. Incubation of muscle homogenate of jumbo squid induced a selective cleavage of myosin into two major fragments and the cleavage was inhibited by EDTA. Autolysis was prominent at and above 0.3 M NaCl where myosin filaments dissolve. The enzyme involved in the autolysis was proved to be unstable showing maximal autolysis rate at 25°C. Washing the homogenate partially reduced the autolysis activity.  相似文献   
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Effect of dietary protein and lipid levels on growth and body composition of juvenile turbot was determined at optimum salinity and temperature conditions of 17 g L?1 and 19.2 °C, respectively, by using 3 × 2 (protein levels: 550, 600 and 650 g kg?1; lipid levels: 69 and 168 g kg?1) factorial design with three replications of each. Fish were hand‐fed to satiety twice daily throughout the feeding trial. Weight gain and specific growth rate of fish were significantly (P < 0.05) increased with increased dietary lipid level, but not by dietary protein level. Daily feed intake was significantly (P < 0.05) affected by both dietary protein and lipid levels. Feed efficiency ratio and protein efficiency ratio were significantly (P < 0.05) affected by dietary lipid level, but not by dietary protein level. Moisture content of whole body was significantly (P < 0.05) affected by dietary lipid level, but not by dietary protein level. Crude lipid content of whole body was significantly (P < 0.05) affected by dietary lipid level, but not by dietary protein level. Significantly higher 20:5n?3, 22:6n?3 and n?3 highly unsaturated fatty acids were observed in turbot fed the low lipid diet than fish fed the high lipid diet in all protein levels, but significantly lower 18:2n?6 was observed in fish fed the former compared with the latter. In considering results of growth, specific growth rate and efficiency of feed, optimum dietary protein and lipid levels for juvenile turbot seemed to be 550 and 168 g kg?1 of the diet, respectively, under optimum salinity and temperature conditions.  相似文献   
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A 3 (protein levels, 380, 460 and 520 g kg–1 diet) × 2 (lipid levels, 65 and 140 g kg–1 diet) factorial experiment with three replicates was conducted. Weight gain, feed efficiency and daily feed intake were not significantly affected by dietary protein level, but were by dietary lipid level. Weight gains of fish fed 65 g lipid kg–1 diet were significantly, or slightly, higher than for 140 g lipid kg–1 diet at all protein levels. Daily protein intake was significantly affected by both dietary protein and lipid levels ( P  < 0.002). Daily lipid intake was not significantly affected by dietary protein level, but was by dietary lipid level ( P  < 0.001). Protein efficiency ratio was significantly affected by dietary protein level ( P  < 0.02), but not by dietary lipid level. Protein efficiency ratio tended to improve with the decrease of dietary protein level at the same lipid level. Moisture, protein and lipid contents of whole fish were significantly affected by dietary lipid level ( P  < 0.01). Increased dietary lipid did not improve growth or feed efficiency, but increased body fat deposition. It was concluded that the optimum dietary protein and lipid level for growth of juvenile ayu may be 380 and 65 g kg–1 diet, respectively, when fish were fed to satiety three times daily in seawater.  相似文献   
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The objective of the present study was to investigate the effects of corn dried distiller's grains with solubles (DDGS) and enzyme premix (mannanase + phytase) supplementation on the growth performance, carcass and meat quality parameters in finishing pigs. Sixty hybrid pigs (L × LW × D) with initial weight of 63.92 ± 1.50 kg were used in a 3 × 2 factorial design with main effects of DDGS levels (0, 10 and 20%) and enzyme premix levels (0% vs. 0.14%). Average daily gain (ADG, P < 0.01) and average daily feed intake (ADFI, P < 0.05) were decreased due to an increased level of DDGS additive while the feed conversion ratio was improved (P < 0.05) by adding enzyme premix. The diet cost/gain (won/kg) was saved (P < 0.01) due to an increased level of DDGS additive. There were no significant differences in carcass characteristics and meat quality parameters of Longissimus dorsi muscle by DDGS level and enzyme premix. Palmitoleic acid, oleic acid and monounsaturated fatty acid (MUFA) decreased (P < 0.05) according to DDGS level. The results indicate that DDGS may be used in feeds for finishing pig as a replacement of corn and soybean meal without affecting their carcass characteristics and meat quality.  相似文献   
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This paper describes a neuroendocrine (NE) tumor of the lung that was observed during the necropsy of a 14-year-old female black spider monkey (Ateles paniscus) with sudden death. Grossly, multifocal firm and coalescing nodular masses were observed in the lung. The histological examination showed the tumor to be an typical NE tumor with polygonal cells grouped in small solid aggregates, with regularly sized, spherical, centrally placed nuclei with modest, lightly granular cytoplasm suspended in a fibrovascular stroma. The immunohistochemical examination revealed the tumor to be positive for cytokeratin, chromogranin A and synaptophysin, and negative for CD56. To the best of our knowledge, this is the first report of NE tumor in the lung of the black spider monkey.  相似文献   
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The global community has committed, as the first priority of the Sustainable Development Goals(SDGs), to end poverty in all its forms everywhere. While the decline of global poverty continues, progress has slowed and remains uneven through different parts of the world. To ensure that no one is left behind in China and beyond, research will be critical to inform paths out of poverty. In this regard, it is valuable to take stock of international experiences and the various pathways out of poverty with a focus on agriculture. Africa's agricultural growth has been largely driven by land expansion and poverty reduction has been the slowest among all regions. South Asia agriculture has been led by diversification of smallholder agriculture and its poverty reduction impact has been large, but its future poverty reduction is limited by rural–urban migration and lack of formal jobs in urban centers. Social protection programs have been used by many Latin American countries as the region is more urbanized than any other developing regions. China's agricultural and economic success was driven by agriculture-led reforms and rural development. These changes brought significantly higher incomes among rural residents, which accounted for highest initial levels of poverty and hunger, and in increased availability of food at affordable prices. Investments in nutrition, health, education, clean water, and good sanitation also complemented progress. The foremost lesson is that smallholder-led agriculture growth in land scarce countries often have the largest impact on poverty reduction. Secondly, nonfarm employment and rural–urban migration must follow once agricultural productivity has reached a certain level. However, premature exiting from agriculture can do more harm. Thirdly, even before large scale poverty reduction through sectoral and regional development is exhausted, social safety nets must be established to cover those who have not benefited from growth and development. Productive social safety nets have proven to be cost-effective in many countries. Urban poverty should also be part of the protection scheme when large proportion of rural population moves to cities.  相似文献   
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