Patterns of Tetracapsuloides bryosalmonae infection of three salmonid species in large,deep Norwegian lakes

Proliferative kidney disease (PKD), caused by the myxozoan endoparasite Tetracapsuloides bryosalmonae, is of serious ecological and economical concern to wild and farmed salmonids. Wild salmonid populations have declined due to PKD, primarily in rivers, in Europe and North America. Deep lakes are also important habitats for salmonids, and this work aimed to investigate parasite presence in five deep Norwegian lakes. Kidney samples from three salmonid species from deep lakes were collected and tested using real-time PCR to detect PKD parasite presence. We present the first detection of T. bryosalmonae in European whitefish in Norway for the first time, as well as the first published documentation of the parasite in kidneys of Arctic charr, brown trout and whitefish in four lakes. The observed prevalence of the parasite was higher in populations of brown trout than of Arctic charr and whitefish. The parasite was detected in farmed, but not in wild, charr in one lake. This suggests a possible link with a depth of fish habitat and fewer T. bryosalmonae-infected and PKD-affected fish. Towards a warmer climate, cold hypolimnion in deep lakes may act as a refuge for wild salmonids, while cold deep water may be used to control PKD in farmed salmonids.     

Gill-associated virus and its association with decreased production of Penaeus monodon in Australian prawn farms

Gill‐associated virus (GAV) was found to be associated with decreased prawn, Penaeus monodon, production when prawns from three farms (n = 45 ponds, 1800 prawns) were monitored for GAV over the production season using a graded RT‐nPCR. The grading system used was a visualization of either the outer or inner nested PCR products. Prevalence and loading of GAV were associated with disease severity. Ponds with a higher initial prevalence and a larger increase in GAV load over the production period suffered disease outbreaks. Ponds with low initial prevalence of GAV but a larger increase in prevalence and large increase in load over the production period suffered chronic disease with no disease outbreak identified, yet low production. However, the ponds with moderate to low initial prevalence of GAV with a low increase in prevalence and load of GAV over the production period incurred no disease outbreak and comparatively high production. Ponds with GAV prevalence greater than 75% at 1 month post‐stocking should be considered for termination as they have a high probability (95%) of having a disease outbreak. Emergency harvest when a disease outbreak occurs will significantly limit mortality losses.     

不同含盐土壤圆盘入渗特征试验

不同含盐土壤水分入渗特征是获得准确的土壤水力参数的基础。该文通过圆盘入渗试验,分析了4种土壤在5个（-1、-3、-6、-9和-12 cm）负水头下的入渗特征。结果表明,随着水头的减小,4种土壤的吸湿率线性减小,稳定入渗率和非饱和导水率呈不同程度减小。随土壤含盐量增加稳定入渗率和导水率呈增大规律。根据实测资料确定了不同负水头下非饱和导水率的Gardner指数模型参数,为盐渍化土壤水力参数的确定提供理论参考。     

鸡眼区相关淋巴组织对ND疫苗点眼免疫应答Ⅱ.眼区局部T淋巴细胞亚群的变化

本研究采用流式细胞仪技术对鸡眼区相关淋巴组织(HALT)在鸡新城疫疫苗点眼免疫后的局部T淋巴细胞亚群的变化进行了研究。研究发现,LaSota 系ND疫苗点眼免疫后眼区相关淋巴组织对ND疫苗可产生良好的细胞免疫应答。免疫组结膜相关淋巴组织(CALT)和哈氏腺(HG)中CD4 T及CD8 T淋巴细胞数量于首免后迅速升高。免疫期间其百分比含量明显高于非免疫组,到40 日龄时,有恢复到正常值的趋势。     

螺旋插补铣在加工多孔盘类零件中的应用

传统的盘类加工工艺方法在加工此类Q345材质零件时，刀具成本较高，生产效率低。通过生产实例的加工工艺，证明了螺旋插补铣在孔加工中的低刀具成本优势与高的生产效率。     

新型稀有元素微肥研制配方的肥效试验

对洛阳市农科所新技术开发公司研制的4个不同配方的新型稀有元素微肥在莲豆上进行了肥效试验，结果表明：Ⅱ^#配方的微肥产品，对莲豆的营养生长和生殖生长均有十分显著的促进作用，不但可以促进莲豆的生长发育，而且可以大幅度地提高莲豆的英果产量，是施用于英果类蔬菜作物营养平衡、肥效较好的最佳配方；Ⅱ^#微肥还可能更广泛地适用于以营养体为收获对象的茎叶类蔬菜作物，在高效多功能生态农业微肥新产品的研制开发方面具有较高的利用价值和广阔的应用前景。     

COMPUTED TOMOGRAPHY OF THE LLAMA HEAD: TECHNIQUE AND NORMAL ANATOMY

Computed tomography was performed on the head of 6 normal adult llamas. The animals were under general anesthesia and positioned in dorsal recumbency on the scanning table. The area scanned was from the external occipital protuberance to the rostral portion of the nasal passage, and the images are presented in both a bone window and a soft tissue window to allow evaluation and identification of the anatomy of the head. Computed tomography of the llama head can be accomplished by most computed tomography scanners utilizing a technique similar to that used in small animals with minor modification of the scanning table.     

基于植株类农作物根施技术产品的开发

工厂化农业是一种受控农业,对作物湿度的变化要求比自然农业大得多。为此,在市场调研的基础上,对现有可控设施环境内植株类农作物根施水肥药等技术中的同类型产品进行了对比研究,运用活塞连杆机构设计并开发了一种新型农用机具,使其密封、安全、通用性能更趋合理。其不但制造成本低廉,而且操作简便,经济实用,具有良好的推广前景。     

平湖剑子麦、洪湖大太宝、崇阳红麦、延岗坊主、万年2号抗赤霉病性基因分析

本试验将抗性组分分析法与单体分析法相结合,进行了小麦抗性基因染色体定位和抗性评价。结果表明,平湖剑子麦是抗性较稳定的中抗至抗病品种,其抗性基因涉及6D、7A、3B、5B和6B 等染色体。洪湖大太宝抗性基因和感病基因并存,是一个中抗偏感或中感品种。崇阳红麦属感病品种。延岗坊主的抗性基因位于染色体3A 上,感病基因位于5D 上,是一个中抗品种.万年2号麦穗前期抗病基因位于4D 和5A 上,是中抗品种。两种方法结合研究多基因控制的赤霉病抗性,能获得比较准确的结果和较多的遗传信息。     

Studies on the Pathogenesis of Shimao Zheng (Fleece-eating) in Sheep and Goats

Research on the disease called shimao zheng, which had resulted in widespread fleece-eating and shedding by sheep and goats in the Haizi area of Akesa County of Gansu Province of China, was carried out by both laboratory studies and pathological observations. There was a marked deficiency of sulfur in the wool and tissues of the affected animals. The pathological changes were mainly loss of fleece, exposure of the skin, keratinization of the epidermal cells, narrowing and reduced numbers of the fleece follicles, and fewer sebaceous glands and sweat glands. Histologically, there was atrophy of the striated and cardiac muscles and of the epithelium of the convoluted tubules of the kidney, together with a glomerulonephritis. The disease was considered to be a local nutritional and metabolic disorder, probably mainly caused by sulfur deficiency.