野古草居群光合作用对光强和CO2浓度的响应特征

以移植于同一环境的辽宁地区4个野古草居群为对象,比较了它们的光合作用对光强和CO₂浓度的响应差异,为研究其居群表型性状多样性的生理基础提供参考。结果表明,野古草光合速率对光强和CO₂浓度的光合响应特征参数在居群间多数存在显著差异,居群P₁(本溪)、居群P₂(北镇)具较高的光饱和点(分别为1782和1690 μmol/m²·s)、表观量子效率(分别为0.0553和0.0564)及表观羧化效率(分别为0.0568和0.0783),较低的CO₂补偿点(分别为14和12 μmol/mol),具有较高的光能生产潜力。居群P₃(建平)、居群P₄(彰武)的气孔导度低(分别为0.1227和0.1176 mol/m²·s),蒸腾速率低(分别为2.67和2.68 mmol/m²·s),持水能力强。     

生长激素轴的组成及其对奶牛泌乳的调控

奶牛泌乳主要受到以生长激素为核心的生长激素轴的调控,其调控原理错综复杂,鉴于此,在前人研究的基础上结合生长激素轴的组成及特点对其调控机制进行简单综述,以期対生长激素的泌乳调控有较深入的了解。     

谷子RNA干扰相关酶类基因家族的鉴定与分析

Dicers酶类、Argonautes蛋白以及RNA依赖的RNA聚合酶(RNA-dependent RNA polymerases,RDRs)是RNA干扰(RNA interference,RNAi)机制中重要的核心蛋白,但在谷子(Setaria italica)中尚无系统报道.为了研究谷子中与RNA干扰相关酶类基因的特征,本研究对谷子的RNA干扰相关酶类基因家族进行了蛋白质理化性质、亚细胞定位预测、蛋白质保守基序、基因保守结构域、基因家族成员间系统发育关系以及组织特异性表达谱分析.研究共发现24个与谷子RNA干扰相关酶类基因,包括7个DCL(Dicers),13个AGO(Argonautes),4个RDRs.系统进化树分析表明,这些家族被分为3个进化支.同一家族基因成员具有共同的保守结构域.虽然大多数基因可同时在不同发育时期的叶、茎和穗中表达,但其在各时期的穗和茎中的表达量最高.本研究为详细探讨这些基因在谷子生殖和生长发育中的表观遗传修饰作用提供了理论依据.     

Genomic differentiation with isolation by distance along a latitudinal gradient in the spotted-leg treefrog Polypedates megacephalus

The patterns of isolation by distance (IBD) entailing increased genetic differentiation among populations have aroused extensive concerns for evolutionary biologists. Although the IBD may act on spatial processes contributing to the genetic differentiation among populations in anuran species, the factors shaping the IBD of frogs among populations in natural systems are largely unknown. Here, we studied the genetic differentiation among six populations with 24 individuals of the spotted-leg treefrog along a latitudinal gradient (1860.31 km) based on 1020 single nucleotide polymorphisms from restriction site-associated DNA sequencing. The results showed that the genetic diversity differed significantly among populations and that the insular populations had higher genetic diversity than the mainland populations. Furthermore, we also found a significant genetic differentiation among populations (F_ST = 0.277) and no sign of inbreeding (F_UNI = −0.145). The IBD was detected for all populations, and a higher degree of the IBD was indicated when controlling for the effects of the isolation between Hainan and mainland populations caused by the Qiongzhou Strait. Our findings suggest that the form of the Qiongzhou Strait plays a key role in shaping the genetic diversity and population differentiation in treefrogs.     

家蚕茧分级和检验方法研究初报

为了适应仪器评茧和提高蚕茧质量,从技术层面研究了统一的家蚕茧分级标准,初步确定了蚕茧分级办法、质量标示、质量综合得分计算方法、检验方法及茧价计算方法等。依照统一的蚕茧分级标准及方法,可促进蚕茧收购与销售“按质评级、分等计价”,有利于“优茧优价”政策的全面实施。     

Toxicosis in newborn pigs associated with cutaneous application of an aerosol spray containing chlorpyrifos

Weakness, lethargy, ataxia, lateral recumbency, limb paddling, tremors, salivation, and diarrhea were observed in newborn pigs on a commercial swine farm. Many pigs became moribund and died. All had been treated with an aerosol wound spray containing 2.5% chlorpyrifos. A controlled study was undertaken to determine whether the aerosol spray was the cause of these clinical signs. Pigs exposed to aerosol spray containing 2.5% chlorpyrifos at 3 hours (n = 4) and 6 hours (n = 3) after birth developed clinical signs similar to those on the farm; none survived. Pigs exposed at 24 hours (n = 5) after birth developed clinical signs consistent with those that had developed in pigs on the farm; 3 died and 2 survived. Of 3 pigs exposed to the same spray at 36 hours after birth, 1 developed tremors 7.5 hours later and diarrhea 9 hours later, then returned to normal.     

卡死克对草地天敌昆虫通缘步甲的影响

试验研究了卡死克对通缘步甲成虫的急性致死毒性及田间撒施卡死克毒饵后对其种群数量消长的影响。室内口腔灌喂250ppm浓度的卡死克药液2μl／头后的第1～15天，灌药组与灌清水组的存活率均在70～90％，统计结果无显著差异，说明药剂对该步甲元急性致死毒性。在毒饵撒施后的7～17天，采用陷阱诱捕法调查对通缘步甲田间种群数量的影响，结果表明：处理区与对照区的日均诱捕数量为28．3和28．5头，两区间的差异并不显著。卡死克既不杀伤草地上游猎捕食的通缘步甲又能有效控制蝗虫种群数量的增长，使其能够发挥控制害虫的作用。通缘步甲发生数量大，与蝗虫种群消长有跟随现象，是一种值得研究保护利用的优势天敌种类。     

限饲对肉鸡的影响

从上世纪20年代肉用仔鸡兴起至今已经过了80多年，这期间科研工作者和生产者无论从肉鸡的选育角度和饲养角度，都是单纯追求提高肉鸡的增重速度，这样虽然使肉用仔鸡的出场日龄大大提前，但肉鸡生长过快，也使肉鸡的体重迅速增长与骨骼、内脏器官发育缓慢之间的矛盾更加突出。肉鸡出现猝死症、腿部畸形和腹水症等疾病，     

野兔圈养管理技术

野兔肉质细嫩、香醇、味美,并含有丰富的人体所需的营养物质,特别是胆固醇含量很低(仅为0.4%),是消费者特别是心血管患者及肥胖者理想的动物蛋白食品。野兔家养成为近几年来发展起来的新兴产业,由于需要较高的管理技术,在很多地方还处于试养阶段,还没有形成规模,野兔的供应还远远不能满足市场的需要,发展前景看好。我所于2006年引进种兔5组,采取圈养的方式进行饲养并获得成功。为了使这一产业在我州得以推广,现将野兔家养的关键技术总结如下。1圈舍的准备根据不同的条件,可修建砖混结构的圈舍,也可利用废弃的猪圈、牛圈、羊圈和鸡鸭舍稍加改…     

Isolation of poxvirus from debilitating cutaneous lesions on four immature grackles (Quiscalus sp.).

Poxvirus was isolated from nodules on four immature grackles (Quiscalus sp.) collected in two residential areas of Victoria, Texas. All of the birds were emaciated and had nodules on the eyelids, bill, legs, toes, and areas of the skin on the wings, neck, and ventral abdomen. These pox nodules were extensive and probably interfered with both sight and flight. The preliminary diagnosis was confirmed by virus isolation, histopathology, and electron microscopy. Poxvirus was isolated on the chorioallantoic membrane of embryonated hen's eggs and in Muscovy duck embryo fibroblast cell culture. Phaenicia calliphoridae (blowfly) larvae were found in one of the pox nodules, raising the possibility of mechanical transmission of the virus by contaminated adult blowflies.