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991.
The effect of partial substitution of dietary fish meal with a high‐value soybean meal (HVS) and a commercial soybean meal (CSM) on the growth performance in juvenile Japanese seabass (8.3±0.2 g body weight) was determined. Nine isonitrogenous (crude protein 44%) and isoenergetic (20 kJ g?1) practical diets replacing 0 (the control), 15%, 30%, 45% and 60% fish meal protein by soybean meal protein (HVS or CSM) were formulated. Each diet was randomly assigned to four replicate cages (1.5 × 1.5 × 2.0 m). Fish were fed twice daily for 10 weeks. Growth was significantly reduced with increased soybean inclusion in fish fed both the soybean sources. Independent of the soybean source used, increased inclusion of soybean meal decreased the growth performance. When the substitution level was 45% or more in CSM and 60% in HVS, the specific growth rate (SGR) and the feed efficiency ratio (FER) were significantly lower compared with the control. These results indicated that CSM protein could substitute for 30% fish meal protein, while the substitution level of HVS protein could be 45%, which did not influence the growth of juvenile Japanese seabass. The higher substitution level for HVS compared with CSM was probably due to better nutritional values.  相似文献   
992.
大亚湾鱼卵、仔稚鱼种群特征与环境因子的相关关系   总被引:2,自引:0,他引:2  
为了解大亚湾鱼卵、稚仔鱼种群动态变化及其与环境因子的关系, 2015年采用浅水I型浮游生物拖网对大亚湾鱼卵、仔稚鱼进行了4个季度的调查,结果表明,4个季度共采获鱼卵31361粒,仔稚鱼244尾。经鉴定分析共有27种,其中鱼卵19种,隶属于6目16科18属;仔稚鱼18种,隶属于5目15科16属;鱼卵、仔稚鱼共有种11个。鱼卵平均丰度为614.55 ind/1000 m^3,稚仔鱼的平均丰度为3.69 ind/1000 m^3。鱼卵丰度季节变化由高到低依次为夏季、春季、冬季、秋季;空间分布显示,丰度由高到低依次为中央列岛、人工鱼礁区、湾口东岸。鱼卵多样性指数(H¢)范围为0.05~2.26,平均值为0.86,稚仔鱼多样性指数(H?)范围为0~2.53,平均值丰度0.82;鱼卵均匀度指数(J)范围为0.02~0.99,平均值为0.50;稚仔鱼均匀度指数(J)范围为0~1.00,平均值为0.52。根据Pearson相关性结果分析表明,与种群关系最密切的环境因子为温度和溶解氧(P<0.01)。研究结果显示,春夏季是大亚湾海域鱼类产卵的重要时期,中央列岛海域是大亚湾鱼类繁殖的关键区域。  相似文献   
993.
Reasons for performing study: Osseous abnormalities. associated with collateral ligament (CL) injury of the distal interphalangeal (DIP) joint have been documented using magnetic resonance imaging (MRI) but there is currently limited information about the frequency of osseous pathology associated with CL injury. Objectives: To determine the frequency of occurrence of osseous abnormality coexistent with CL injury of the DIP joint and describe the distribution and character of osseous lesions; and to establish if there was an association between osseous abnormality and increased radiopharmaceutical uptake (IRU). Hypotheses: There would be a higher incidence of osseous abnormality at the insertion of an injured CL than at the origin; and a relationship between the presence of osseous abnormality and duration of lameness. Materials and methods: Magnetic resonance images of 313 feet of 289 horses with foot pain and a definitive diagnosis of collateral desmopathy of the DIP joint were analysed retrospectively for presence and type of osseous abnormality in the middle and distal phalanges. Scintigraphic images were examined and the presence of IRU in the middle or distal phalanges recorded. Results: Osseous abnormalities were detected in 143 (45.7%) feet, 27 (18.8%) of which had osseous and CL injury alone, while the remaining 116 had CL related osseous injury and multiple injuries within the hoof capsule. Entheseous new bone and endosteal irregularity of the middle and distal phalanges were the most frequent types of osseous abnormality. There was a higher incidence of osseous abnormalities medially than laterally and at the ligament insertion than at the origin. There was a significant association between presence of IRU and osseous injury. Conclusions: A variety of osseous lesions of differing severity are associated with CL injury. Normal radiopharmaceutical uptake does not preclude significant osseous pathology associated with CL injury. Clinical relevance: Further studies are necessary in order to determine if osseous abnormalities associated with CL injury influence prognosis for return to performance.  相似文献   
994.
2011年6月3日~6月21日和8月2日~8月20日,调查了黄河干流山西段鱼类组成的现状及群落结构特征。结果表明,全段共采集鱼类42种,隶属5目9科,其中以鲤科鱼类最多,共24种,占总种数的57%。渔获物数据表明,该流域小型鱼类较多,小型化现象明显,优势种为鲤、残、鲶、鲫,和麦穗鱼。物种组成差异和多样性分析结果表明,不同河段鱼类群落有明显的空间分异,风陵渡、刘家畔、关河口、圣天湖物种丰富,多样性水平高,群落结构稳定,而军渡和老牛湾物种少,群落较为简单。与历史资料相比,黄河干流山西段鱼类物种数减少,群落结构发生了较大变化。水体污染、大量水工建筑以及过度捕捞等因素是导致变化的主要原因。  相似文献   
995.
万佛湖初级生产力和鱼产力的评估与分析   总被引:1,自引:1,他引:1  
利用浮游生物计数法和黑白瓶测氧法对万佛湖的初级生产力进行测定,并以此对万佛湖鲢、鳙鱼产量进行测算.结果表明,浮游生物计数法评估万佛湖鲢、鳙鱼产力达1100~2000t,黑白瓶法评估鱼产力为2200t.比万佛湖实际产量高很多,说明水库的鱼产力尚未达到上限.  相似文献   
996.
提出了一种基于电容式湿度传感器的植物粉料含水率测量方法。由电容式湿度传感器和数据采集卡组成的测量系统获取植物粉料含水率数据,应用一阶差分法剔除奇异值后,通过惯性滤波法处理数据。由菊花粉含水率的13个测量值与烘干法测得的真值对比试验结果可知,测量值与真值之间的最大相对误差为1.61%,平均相对误差为0.76%,均小于5%(测量样品数为5时置信区间为95%),表明该方法能够用于测量低水分植物粉料的含水率。  相似文献   
997.
不同阶段猪用颗粒饲料物理性能的对比分析   总被引:1,自引:0,他引:1  
对某饲料厂不同阶段猪用4种颗粒饲料的物理性能包括直径、长度、硬度、容重、含粉率和耐久性指数(Pellet Durability Index, PDI)等进行测定,对结果进行归类总结并采用统计学的方法参照有关标准进行分析。结果表明,4种颗粒饲料直径在2.87~3.94 mm之间,母猪料直径最大,小猪料最小,两两之间差异显著(P<0.05),而且随着猪只年龄的增加,颗粒饲料的直径呈递增趋势。颗粒长度在8.62~11.94 mm之间,以大猪料最长,小猪料最短,长径比偏高。颗粒硬度在3.86~6.47 kg之间,以大猪料最大,小猪料最小,中小猪料显著低于大猪料和母猪料(P<0.05),只有小猪料符合有关要求。颗粒容重在576.7~614.6 g/L之间,母猪料最大,小猪料最小,两两之间差异显著(P<0.05),与直径呈相同的增减趋势。含粉率以小猪料最大,且只有小猪料与大猪料之间差异显著(P<0.05)。颗粒PDI以大猪料最大,小猪料最小,各阶段猪料的含粉率和PDI均符合有关要求。建议饲料厂家注重颗粒饲料物理性能指标的控制,调整饲料配方和工艺参数,不断改进颗粒饲料的质量。  相似文献   
998.
为探索竹粉替代面粉填充脲醛树脂胶黏剂的可行性,减少面粉在非食品工业的消耗,充分利用竹材加工剩余物,以竹粉作为脲醛树脂胶黏剂的填充剂,研究了竹粉的添加量、粒度对脲醛树脂胶黏剂的粘度、胶合性能和甲醛释放量的影响,以及竹粉在胶液中的分散情况,并采用傅里叶变换红外光谱对添加了竹粉的脲醛树脂胶黏剂进行了分析。结果表明:竹粉在脲醛树脂胶液中易分散,且随竹粉粒度的减小,竹粉分散越均匀;竹粉粒度、添加量对脲醛树脂胶黏剂的胶合强度有较显著的影响,但对甲醛释放量的影响不显著;当添加量为脲醛树脂胶黏剂( UF)胶液质量15%的220-240目竹粉时,竹粉填充不影响其胶合强度和甲醛释放量。  相似文献   
999.
本试验旨在研究日粮中添加不同剂量葡萄籽粉替代玉米对成年母羊体重和经济效益的影响。试验选取年龄相近(15~16月龄)、健康状况良好的成年母羊32只,根据体重相近原则随机分为4组,对照组饲喂基础日粮,试验Ⅰ、Ⅱ和Ⅲ组分别用葡萄籽粉替代基础日粮中7%、14%和21%玉米。结果表明,试验各组间羊增重差异不显著(P>0.05),但试验Ⅰ组平均日增重比对照组提高了14.50%,且经济效益比对照组平均提高了37.74%。提示,本试验中在基础日粮中使用葡萄籽粉替代7%玉米对成年母羊的增重效果和经济效益最佳。  相似文献   
1000.
Infrastructure development and overfishing in the Amazon make it imperative to define adequate scales for the ecosystem‐based management of commercial fisheries and the wetlands on which they depend. We mapped fisheries and fish ecology data from Brazil, Peru, Bolivia and Colombia to an explicit GIS framework of river basins and mainstems. Migratory species account for more than 80% of the known maximum catches of commercial fisheries across the Amazon. Of these migratory species, we nominated six long‐distance migratory fish taxa as flagship species to define the two main commercial fishery regions. The migrations of at least one goliath catfish species define a large‐scale longitudinal link joining the Andes, Amazon Lowlands and Amazon River estuary. Migratory Characiforms demonstrate interbasin wetland connectivity between nutrient‐rich and nutrient‐poor rivers over at least 2 million km2, or about one‐third of the Amazon Basin. We show that flooded forest area is the most important wetland variable explaining regional variations in migratory characiforme biomass as indicated by maximum annual fishery catches. The sustainable management of Amazon fisheries will require transnational cooperation and a paradigm shift from local community management alone to a more integrated approach that considers both rural and urban consumers and challenges, and the realistic life histories of migratory species.  相似文献   
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