自由放养下绵羊的营养参数

根据绵羊的营养参数和饲养标准,结合日增重水平,计算了不同日增重水平对应的体重月平均动态及其所对应的粗蛋白日需要量和代谢能日需要量。不同日增重水平,达到生长期望所需要的日数不同,日增重水平越高,达到生长期望总所需要的粗蛋白和代谢能越少,但月平均的日需要量越多。自由放养的东北细毛羊当年生羔羊的日增重水平仅相当于舍饲饲养日增重的100g水平,根据代谢能计算,年总需干草340kg,可以作为计算载畜量的基本参数。自由放养情况下,即使能量满足需要,粗蛋白也短缺。当年生羔羊日增重在150￣200g,9￣10月龄内体重达到46￣50kg是北方草地家畜生产的理想目标,通过补饲可以实现。     

Ovipositor length of threeApocrypta species: Effect on oviposition behavior and correlation with syconial thickness

We investigated oviposition behavior in three non-pollinating fig wasps: the sympatric speciesApocrypta bakeri Joseph onFicus hispida L.,A. westwoodi Grandi onF. racemosa L., andApocrypta sp. onF. semicordata Buch.-Ham. The oviposition behavior differs significantly between one pair of species (A. bakeri andA. westwoodi) and the other species (Apocrypta sp. onF. semicordata).A. bakeri andA. westwoodi were similar in the following aspects: the posture of the abdomen and the action of the hind legs before penetration, and the bending ovipositor sheath during penetration. In contrast, the oviposition behavior ofApocrypta sp. is quite different. This difference can be explained by the significant correlation between ovipositor length and syconial thickness.Apocrypta sp. has a shorter ovipositor than the two other species, which correlates with the thinner syconial wall of its host figF. semicordata. It is deduced that the ovipositor length adapts to the syconial thickness and induces the oviposition behavior in the different species to diverge. For all threeApocrypta species, the midleg length and hindleg length are significantly correlated with their ovipositor lengths. This may be explained as due to the fact that body movement adjusting the hindlegs and midlegs up and down, or forward and backward, is also influenced by the ovipositor length.     

哺乳犊牛的消化特点与蛋白质需要

本文从犊牛的消化生理特点出发,综述了犊牛出生后的生理特征及蛋白质、必需氨基酸的需要量,并对代乳品中蛋白质原料进行了论述。     

潜叶蝇在大庆市日光温室蔬菜上的发生与为害

对潜叶蝇在北方节能日光温室蔬菜上的发生和为害进行调查研究。结果表明,3～11月潜叶蝇在日光温室蔬菜上均有发生,其中5月中旬～6月中旬、9月下旬～10月中旬是为害高峰期;一日中9:00～11:00、13:00～15:00是潜叶蝇成虫为害高峰期;3月下旬、6月上中旬潜叶蝇/明显升高。     

Relationship between the intracellular calcium concentration changes and left ventricular hypertrophy and function in the spontaneously hypertensive rats

AIM:To elucidate the relationship between the intracellular calcium concentration changes and left ventricular hypertrophy and function in the spontaneously hypertensive rats (SHR).METHODS:Intracellular free calcium concentrations were measured by Fura 2 methodology and left ventricular function quantitated by cardiac catheterization in 20 SHR aged 10, 22, and 34 weeks and 20 age-matched Wistar-kyoto (WKY) rats.RESULTS:(1) The systolic blood pressure(SBP), intracellular calcium concentrations and left ventricular mass / body weight index (LVM/BW) were significantly higher in all three age groups of SHR than the corresponding groups of WKY; (2) Compared with age-matched WKY groups, the peak left ventricular pressure descending rate(-dp／dt_max) decreased while left ventricular relaxation time constant (τ)increased significantly in SHR aged 22 and 34 weeks. The peak left ventricular pressure ascending rate(dp／dt_max) and the left ventricular contractility index were significantly increased only in the 34 weeks SHR; (3) Intracellular calcium concentrations showed a positive correlation with LVM/BW,SBP,-dp／dt_max and τ(r=0.47-0.83,P<0.01)and a negative correlation with dp／dt_max and the left ventricular contractility index (r=-0.46,P<0.05 and r=-0.81, P<0.01).CONCLUSION:Intracellular calcium overload is one of the potential mechanisms in the induction of left ventricular hypertrophy as well as of systolic and diastolic dysfunction.     

Cell proliferation and nestin expression in cortex and SEZ of MCAO rats

AIM:To explore the effect of brain ischemia injury on cell proliferation and nestin expression in cortex and subependymal zone (SEZ).METHODS:Using a local brain ischemia model(MCAO), BrdU positive cells of cortex and subependymal zone (SEZ), also nestin positive cells, were observed by immunohistochemistry.RESULTS:BrdU and nestin positive cells in SEZ of MCAO rats were obviously increased. In cortex, only nestin positive cells were observed.CONCLUSION:Neural stem cells in SEZ and cortex were activated after brain ischemia, it may be related with neural recovery after brain ischemia injury.     

咯菌腈对草莓灰霉病Botrytis cinerea的毒力及防效研究初报

用生长速率法测定了咯菌腈、多菌灵、硫菌·霉威、苯醚甲环唑4种药剂对草莓灰霉病Botrytis cinerea的毒力。结果表明,4种药剂对草莓灰霉菌菌丝的生长都有不同程度的抑制作用,随药剂浓度增加抑制作用增强,其EC50值分别为0.0472、95.7193、0.4854、1.3611 mg/L,其中咯菌腈的毒力最强。田间防治试验结果表明:2.5%咯菌腈FC每667 m2施药量120 mL时防效为83.7%,80 mL时防效为67.7%;65%硫菌·霉威WP每667m2施药量100 g时防效为65.3%。     

苏云金杆菌小试生产发酵影响因子的研究

利用 1 0L全自动发酵罐对苏云金杆菌小试生产的发酵条件进行了研究。结果显示 ,不同的温度、pH值、培养基成分及接种方式对发酵产量和发酵周期均有影响 ;在培养基配方中存在葡萄糖时 ,葡萄糖单独灭菌对提高苏云金杆菌发酵产量是重要的。初步生物测定显示 ,发酵上清中存在一些杀虫增效因子 ,建议配制苏云金杆菌制剂时尽可能加以利用。     

姬松茸与双孢蘑菇不同菌株的RAPD扩增研究

以4个姬松茸菌株和2个双孢蘑菇菌株为材料，用20个随机引物对它们进行RAPD扩增，通过对供试菌株遗传相似系数的估算和系统聚类分析，构建姬松茸和双孢蘑菇遗传相关树状聚类图谱，结果表明，进行RAPD扩增的20个随机引物中，有12个能产生三种带型，当遗传相似系数升至0.8713时，这6个菌株被分为3类，第一类为菌株18和26，第二类为菌株13和12，第三类为菌株33和45。     

莴苣‘红帆’品种下胚轴愈伤组织诱导与植株再生

 莴苣下胚轴愈伤组织诱导时, MS+ 6-BA 0. 5 mg/ L+ 2, 4-D 1 mg/ L+ NAA 0. 1 mg/ L 效果最好,出愈率达94%; 愈伤组织分化为芽时, MS+ 6-BA 1. 0 mg / L+ NAA 0. 05 mg/ L 分化频率最高, 达100% ; 再生苗在1/ 2MS+ NAA 0. 5 mg/ L 中诱导生根成为完整植株。