中国草鱼和泰国草鱼利用牧草作食饵的比较

通过对中国草鱼（Ｃｔｅｎｏｐｈａｒｙｎｇｏｄｏｎｉｄｅｌｌａ）和泰国草鱼（Ｐｕｎｔｉｕｓｇｏｎｉｏｎｏｔｕｓ）分别在常规的尼罗罗非鱼（Ｏｒｅｃｈｒｏｍｉｓ，ｎｉｌｏｔｉｃｕｓ）、鲤鱼（Ｃｙｐｒｉｎｕｓｃａｒｐｉｏ）和黑鱼（Ｃｈａｎｎａｓｔｒｉａｔａ）混养体系中养殖７个月，比较两者对牧草（Ｂｒａｃｈｉａｒｉａｍｕｔｉｃａ）的利用效果。试验结果表明，中国草鱼与泰国草鱼相比，无论是每尾体重，还是每尾体长、平均每尾日增重都有明显优势（Ｐ＜０．０５）．而且，放养３个月后，中国草鱼每尾体重和每尾日增重均极显著地优于泰国草鱼（Ｐ＜０．０１）．中国草鱼和泰国草鱼的年产量分别为２１８６ｋｇ／ｈｍ￣２，１２３３ｋｇ／ｈｍ￣２．中国草鱼的成活率比泰国草鱼低，两者分别为３８％和８６％。     

银皖鲫生物学的初步研究

银皖鲫是以方正银鲫作母本，草鱼作父本，进行远缘杂交培育的新型鲫鱼品种，具有适应性强、生长快、食性广、易饲养、耐低氧、抗病力强等特点，是池塘养殖的优良品种。     

氨氮胁迫对四鼻须鲤鱼肝脏GST酶活力的影响

实验采用生态毒理学方法,以NH4Cl为实验药物,设置0、50、150和250mg/L实验浓度。通过对野生和养殖群体的四鼻须鲤鱼氨氮对肝脏谷胱甘肽巯基转移酶（GST）活力的影响,比较两个群体抗氨氮能力。结果表明：在相同的氨氮浓度和胁迫时间下,四鼻须鲤鱼养殖群体GST酶活力的变化趋势与野生群体大致相同。除250mg/L浓度组在胁迫5d和10d时,野生群体酶活性略低于养殖群体外,在其余时间点的野生群体酶活性均高于养殖群体,而且,在高浓度氨氮胁迫下,野生群体肝脏的GST酶活性达到峰值的时间比养殖群体更短,显示出较强的抗氨氮能力。     

Sulfadiazine pharmacokinetics in grass carp (Ctenopharyngodon idellus) receiving oral and intravenous administrations

This study aimed to examine the bioavailability (BA) and pharmacokinetic (PK) characteristics of sulfadiazine (SDZ) in grass carp (Ctenopharyngodon idellus) after oral and intravenous administrations. Blood samples were collected at predetermined time points of 0.083, 0.17, 0.5, 1, 2, 4, 8, 16, 24, 48, 72, and 96 hr (n = 6). The samples were extracted and purified by organic reagents and determined by the ultra‐performance liquid chromatography. The software named 3P97 was used to calculate relevant PK parameters. The results demonstrated that the concentration–time profile of SDZ was best described by a one‐compartmental open model with first‐order absorption after a single oral dose. The main PK parameters of the absorption rate constant (K_α), the absorption half‐life (t_{1/2 Kα}), the elimination rate constant (K_e), the elimination half‐life (t_1/2Ke), and the area under concentration–time profile (AUC_0‐∞) were 0.3 1/h, 2.29 hr, 0.039 1/h, 17.64 hr, and 855.78 mg.h/L, respectively. Following intravenous administration, the concentration–time curve fitted to a two‐compartmental open model without absorption. The primary PK parameters of the distribution rate constant (α), the elimination rate constant (β), the distribution half‐life (t_1/2α), the elimination half‐life (t_1/2β), the apparent distribution volume (V_SS), the total clearance (CL), and AUC_0‐∞ were 9.62 1/hr, 0.039 1/hr, 0.072 hr, 17.71 hr, 0.33 L/kg, 0.013 L h^?1 kg^?1, and 386.23 mg.h/L, respectively. Finally, the BA was calculated to be 22.16%. Overall, this study will provide some fundamental information on PK properties in the development of a new formulation SDZ in the future and is partially beneficial for the appropriate usage of SDZ in aquaculture.     

山西草地螟发生预测模糊近似推理模型

模糊近似推理方法是模糊集理论应用前景十分广泛的一种方法.我们用此法为山西草地螟发生预测建立了一个模糊近似推理模型,初步试用效果满意.本文在模型的预报输出中引用了特征展开近似推理方法,大幅度地简化了运算过程;并且使得模型可以带入较多的因素.     

反转旋耕刀滑切角分析与计算

对反转旋耕刀滑切角的分析与计算表明：反转旋耕刀滑切角的意义及方程与正转旋耕刀相同，可以按照统一的方法描述旋耕刀滑切角的特性，并计算其大小。由于工作范围不同，反转旋耕刀滑切角是从大逐渐减小的，其变化规律与正耕刀不同。如果反旋刀入土时不能满足滑切要求，则在整个切土过程中都不满足滑切要求。在切土阶段，反转旋耕刀的动态滑切角大于正转旋耕刀，但由于反转旋耕切草类似于无支承切割以及反旋刀抛土性能差等特点，反转旋耕刀的缠草总是仍然比较突出。     

Modelling carbon dynamics in mixed grass–red clover swards

Growth and carbon dynamics in mixed grass–red clover leys were simulated using a growth model for pure stands based on radiation use, allocation within plant and loss of biomass. The model and its parameter values were taken from previous applications of the model to pure swards of grass and red clover grown in the same experiment at the same sites and years.     

双低菜籽粕对草鱼和鲤甲状腺、肝、肾组织结构的影响

以组织学方法,研究了投喂不同含量双低菜籽粕对草鱼和鲤甲状腺、肝、肾组织的影响。结果表明:在试验的前28 d,双低菜籽粕各不同含量的日粮(17%、34%、51%、68%)对草鱼甲状腺、肝脏组织没有影响,但菜籽粕含量为68%的试验组草鱼肾小管上皮出现颗粒变性。第42天后,菜籽粕含量为68%的试验组草鱼甲状腺滤泡上皮轻度增生,滤泡结构不规则;菜籽粕含量等于或大于51%的试验组草鱼肝脏出现颗粒变性和空泡变性,肾小球有透明变性,肾脏轻度淤血。在试验的第28天,双低菜籽粕含量等于或大于52.2%的试验组鲤甲状腺滤泡上皮细胞的高度增加,肝细胞空泡变性,有轻微的肾小球透明变性。第42天后菜籽粕含量等于或大于34.8%的试验组鲤甲状腺滤泡上皮细胞的高度增加,滤泡胶质的边缘出现缺刻;肝脏出现淤血,部分肝细胞坏死;肾小球透明变性,肾脏淤血。     

谷氨酸铜对罗非鱼和草鱼生长性能血清生化指标和体组成的影响

为研究谷氨酸铜制剂对罗非鱼、草鱼的生长性能、血清生化指标和鱼体组成的影响，选用180尾罗非鱼、135尾草鱼，分别随机分为3个处理组，每组3个重复，每个重复20或15尾。在基础饲料中添加五水硫酸铜作为对照组（10 mg/kg），试验组添加谷氨酸铜（高、低剂量组分别为10、5 mg/kg，按铜离子计），饲养8周。结果表明：与对照组相比，谷氨酸铜高、低剂量组罗非鱼的增重率分别提高3.9%和5.8%，草鱼的增重率分别提高4.0%和5.9%；罗非鱼特定生长率分别提高1.9%和3.3%，草鱼分别提高2.5%和3.5%；罗非鱼和草鱼的平均饵料系数分别降低7.6%和3.7%。两种鱼的血清生化指标及体组成各试验组间均无显著差别（P＞0.05）。由此可见，日粮中添加适量谷氨酸铜可提高鱼体的生长性能，且效果优于五水硫酸铜。     

Spatial variability of common carp populations in relation to lake morphology and physicochemical parameters in the upper Midwest United States

Weber MJ, Brown ML, Willis DW. Spatial variability of common carp populations in relation to lake morphology and physicochemical parameters in the upper Midwest United States.
Ecology of Freshwater Fish 2010: 19: 555–565. © 2010 John Wiley & Sons A/S Abstract – Common carp (Cyprinus carpio) is a widespread invasive species that is tolerant of a wide range of environmental conditions. Despite the circumpolar distribution of the species, limited information is available describing factors related to spatial variation in population characteristics. Eighty‐four lakes and impoundments in the upper Midwest United States were sampled to investigate the relationships of common carp relative abundance with size structure, condition and growth rates. We also investigated abiotic factors (lake morphology, physical solids and water quality) that may broadly influence common carp populations. Common carp size structure and condition were inversely related to relative abundance. Common carp relative abundance increased and size structure shifted to smaller individuals with increased lake depth, whereas lake surface area, watershed:surface area ratio and physical solids were also important in explaining common carp abundance and size structure. Common carp condition was best explained by water quality parameters and increased with metrics of lake productivity. We conclude that knowledge of factors associated with variation in common carp populations among lakes provides insights into the autecology and broad provisions for management of this generalist invasive species.