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101.
Solomon Tulu TADESSE Oene OENEMA Christy van BEEK Fikre Lemessa OCHO 《农业科学与工程前沿(英文版)》2021,8(1):159-174
102.
103.
本研究遵循动物福利"5F"原则,结合150家规模化奶牛养殖场实地调研数据,构建奶牛场动物福利评价体系,测度动物福利水平,并进一步建立嵌入动物福利水平测度值的规模化奶牛养殖场收入函数,验证关联效应.结果表明:生理福利和环境福利是影响我国规模化奶牛养殖场动物福利的最重要的2个维度,受访的规模化奶牛养殖场生理福利和环境福利的... 相似文献
104.
Fish contribute a significant amount of animal protein to the diets of people in Bangladesh, about 63% of which comes from aquatic animals. In Bangladesh, fish is mainly derived from two sources: capture and culture. Aquaculture has shown tremendous growth in the last two decades, exhibiting by about 10% average annual growth in production. Capture fisheries, although still the major source of supply of fish, have become static or are in decline due to over‐fishing and environmental degradation, and it is now believed that aquaculture has the greatest potential to meet the growing demand for fish from the increasing population. At present, aquaculture production accounts for about one‐third of the total fish production in Bangladesh. This paper examines the impact of an aquaculture development project in Bangladesh on food security, with particular emphasis on the poor. The analysis shows a positive impact of aquaculture development on employment, income and consumption. A number of implications for policy in areas that might strengthen these outcomes are discussed and recommendations are presented. 相似文献
105.
Abstract Condition indices are often used as surrogates of fish health, growth, and feeding and to compare ecological well-being among fish populations. In an effort to identify easily measured indices, growth and food consumption were compared with gonadal-somatic index, liver-somatic index (LSI), fat-somatic index and relative weight ( W r ) for ages 1–3 walleye, Sander vitreus (Mitchill), in Lake Erie from 1986 to 1988. The LSI and W r were significantly correlated with growth rate or food consumption, but correlations were too small to be considered biologically meaningful. Furthermore, no consistent relationships between condition indices and growth or consumption were found among combinations of fish age and season. None of the indices are considered reliable surrogates for more laborious estimates of growth and food consumption for Lake Erie walleye. Significant relationships between W r and relative abundance of key prey species warrant further investigation. 相似文献
106.
逆流运动训练对多鳞四须鲃摄食、生长和体营养成分的影响 总被引:6,自引:2,他引:6
在室内条件下[水温(28?1) ℃],设置0.7 BL/s和2.0 BL/s 2个流速组以及一个静水对照组,研究了不同逆流运动训练对多鳞四须鲃幼鱼[体质量(75.21?2.82) g]摄食、生长和体营养成分的影响。实验分1~23 d和23~45 d两个阶段,共进行45 d。实验结果表明,多鳞四须鲃平均日摄食率随流速增加而增大,但体长特定生长率、体质量特定生长率和食物转换率均以0.7 BL/s组最高,静水组次之,2.0 BL/s组最低,且三者间差异显著(P<0.05)。不同流速下多鳞四须鲃肌肉水分和灰分含量差异不显著(P>0.05),但随流速增大,多鳞四须鲃肌肉中蛋白质含量增加,而脂肪含量却显著下降。在实验末期,2.0 BL/s流速组的氨基酸总含量(82.63%)、必需氨基酸总含量(34.34%)和鲜味氨基酸总含量(33.50%)均显著高于静水对照组(78.27%,32.6%,30.63%)(P<0.05)。研究表明,较低流速(0.7 BL/s)的运动训练明显促进多鳞四须鲃的生长,提高食物转化率和增加肌肉蛋白质含量,高流速(2.0 BL/s)的运动训练不利于生长,但却能显著提高肌肉必需氨基酸和鲜味氨基酸含量。 相似文献
107.
《Journal Of Applied Aquaculture》2013,25(3):101-111
ABSTRACT The production ability of freshwater rotifer, Brachionus calyciflorus, cultured with two algal species, Chlorella vulgaris, and Spirulina platensis, and a baker's yeast, Saccharomyces cerevisiae, were studied using semicontinuous culture method. B. calyciflorus was fed with the above three types of food at five different concentrations (125, 250, 500,750, and 1,000 μg/mL). Among the three different types of diet, maximum production of B. calyciflorus (489.20 ±10.91 individuals/mL; P < 0.05) was obtained with C. vulgaris, followed by S. cerevisiae, and S. platensis. Moreover, in each of the three diets, the maximum rotifer production was obtained at a particular concentration (C. vulgaris, 750 μg/mL; S. cerevisiae, 750 μg/mL; and S. platensis, 500 μg/mL) beyond which the rotifer production decreased. The peak production due to C. vulgaris (489 individuals/mL) was better than S. cerevisiae (321 individuals/mL) when the number of rotifers was considered. The present study indicates that the quantity and quality of food have a significant role on the rotifer production and that C. vulgaris at 750 μg/mL appears suitable to feed to rotifers for maximal production. 相似文献
108.
T. Ahmad S.P. Singh B.K. Khangembam J.G. Sharma R. Chakrabarti 《Aquaculture Nutrition》2014,20(3):265-272
The effect of temperature on the food consumption rate and the digestive enzyme activities of Clarias batrachus (80.60 ± 5.34 g) were evaluated. Fish were exposed to six different temperatures of 10, 15, 20, 25, 30 and 35 °C following an acclimation temperature of 25 °C. The rate of temperature change was 2 °C day?1. Highest food consumption was recorded at 25 °C. It gradually reduced with decreasing water temperature. Food consumption rate was significantly (P < 0.05) lower at 10 °C compared with other treatments. Hence, 46.67, 8.20–23.58 and 1.02–6.15% reduced food consumptions were recorded in groups exposed at 10, 15 and 20 °C temperatures, respectively, compared with the 25 °C. The consumption rate was not affected in fish exposed at 30 and 35 °C. Total protease, trypsin and chymotrypsin activities were significantly (P < 0.05) higher in fish exposed at 25 °C compared with others. Lipase activity was significantly (P < 0.05) higher in fish exposed at 30 °C compared with others. Lowest enzyme activities were recorded at 10 °C. Water temperature below 25 °C affected the food consumption and digestive enzyme activities in fish that served as indicators of stress in fish. 相似文献
109.
Hongsheng Yang Xiutang Yuan Yi Zhou Yuze Mao Tao Zhang & Ying Liu 《Aquaculture Research》2005,36(11):1085-1092
To investigate the effects of body size and water temperature on feeding and growth in the sea cucumber Apostichopus japonicus (Selenka), the maximum rate of food consumption in terms of energy (Cmaxe; J day?1) and the specific growth rate in terms of energy (SGRe; % day?1) in animals of three body sizes (mean±SE) – large (134.0±3.5 g), medium (73.6±2.2 g) and small (36.5±1.2 g) – were determined at water temperatures of 10, 15, 20, 25 and 30°C. Maximum rate of food consumption in terms of energy increased and SGRe decreased with increasing body weight at 10, 15 and 20°C. This trend, however, was not apparent at 25 and 30°C, which could be influenced by aestivation. High water temperatures (above 20°C) were disadvantageous to feeding and growth of this animal; SGRe of A. japonicus during aestivation was negative. The optimum temperatures for food consumption and for growth were similar and were between 14 and 15°C, and body size seemed to have a slight effect on the optimal temperature for food consumption or growth. Because aestivation of A. japonicus was temperature dependent, the present paper also documented the threshold temperatures to aestivation as indicated by feeding cessation. Deduced from daily food consumption of individuals, the threshold temperature to aestivation for large and medium animals (73.3–139.3 g) was 24.5?25.5°C, while that for small animals (28.9–40.7 g) was between 25.5 and 30.5°C. These values are higher than previous reports; differences in sign of aestivation, experimental condition and dwelling district of test animals could be the reasons. 相似文献
110.