兽药使用环节存在的问题及对策

经过对兽药生产厂家和经营企业几年的整治,尤其是新<兽药管理条例>和<兽药标签和说明书管理办法>出台后,又经过GMP认证,兽药生产经营市场秩序和经营行为得到了一定的规范.但兽药使用环节中却存在诸多的问题,如:违法使用人用药品;违法使用禁用兽药;不执行休药期规定;未建立台帐等等.这些问题的存在,直接导致了动物产品的安全性问题.对此,笔者分析了兽药使用环节存在问题的原因,并对解决这些问题提出了个人观点.     

正交试验法优化普抗合剂制备工艺

以干浸膏得率和黄芩苷提取率为考核指标,采用正交试验法对普抗合剂水提取醇沉淀制备工艺进行考察.普抗合剂最佳制备工艺方案为加水量10倍,提取2次,每次1 h,55%的乙醇沉淀杂质 .该工艺科学合理,适合于大规模工业生产.     

Forest management and forest state in southern Sweden before and after the impact of storm Gudrun in the winter of 2005

About three times the annual cut in southern Sweden (Götaland) was damaged by the storm Gudrun in January 2005, i.e. almost as much as the normal annual cut for all of Sweden. To establish any differences in forest management and state before and after the storm, measures such as growing stock volume, age-class distribution, and species composition were analyzed within the damaged area. As a reference the situation before and after the storm within the area in Götaland not damaged by the storm was also analyzed. For all analyses, sample plots from the Swedish National Forest Inventory were used. Results based on mean values for the years 2000–2004/2005–2009 showed that the total growing stock for the damaged area decreased by approximately 30 million m³ after the storm. This was mainly caused by a decrease in Norway spruce (Picea abies (L.) H. Karst). Annual growth for pine, spruce, and deciduous trees decreased by 1.8 million m³ in the damaged area. This mainly included stands already thinned and not, as expected, in the stands ready for final felling. Also, the proportional area within each of the age classes 21–40, 41–60, and 61–80 years decreased. The storm led to an increased area in immediate need of precommercial thinning. No changes in choice of species when regenerating could be observed. Furthermore, only marginal adaptation by forest owners to future risk of wind throw could be detected.     

Zooming in on a quantitative trait for tomato yield using interspecific introgressions

To explore natural biodiversity we developed and examined introgression lines (ILs) containing chromosome segments of wild species (Solanum pennellii) in the background of the cultivated tomato (S. lycopersicum). We identified Brix9-2-5, which is a S. pennellii quantitative trait locus (QTL) that increases sugar yield of tomatoes and was mapped within a flower- and fruit-specific invertase (LIN5). QTL analysis representing five different tomato species delimited the functional polymorphism of Brix9-2-5 to an amino acid near the catalytic site of the invertase crystal, affecting enzyme kinetics and fruit sink strength. These results underline the power of diverse ILs for high-resolution perspectives on complex phenotypes.     

Conserved eukaryotic fusogens can fuse viral envelopes to cells

Caenorhabditis elegans proteins AFF-1 and EFF-1 [C. elegans fusion family (CeFF) proteins] are essential for developmental cell-to-cell fusion and can merge insect cells. To study the structure and function of AFF-1, we constructed vesicular stomatitis virus (VSV) displaying AFF-1 on the viral envelope, substituting the native fusogen VSV glycoprotein. Electron microscopy and tomography revealed that AFF-1 formed distinct supercomplexes resembling pentameric and hexameric "flowers" on pseudoviruses. Viruses carrying AFF-1 infected mammalian cells only when CeFFs were on the target cell surface. Furthermore, we identified fusion family (FF) proteins within and beyond nematodes, and divergent members from the human parasitic nematode Trichinella spiralis and the chordate Branchiostoma floridae could also fuse mammalian cells. Thus, FF proteins are part of an ancient family of cellular fusogens that can promote fusion when expressed on a viral particle.     

A comparison of the use of different swab materials for optimal diagnosis of amoebic gill disease (AGD) in Atlantic salmon (Salmo salar L.)

Routine gill swabbing is a non-destructive sampling method used for the downstream qPCR detection and quantitation of the pathogen Neoparamoeba perurans, a causative agent of amoebic gill disease (AGD). Three commercially available swabs were compared aiming their application for timelier AGD diagnosis (Calgiswab^® (calcium alginate fibre-tipped), Isohelix^® DNA buccal and cotton wool-tipped). Calcium alginate is soluble in most sodium salts, which potentially allows the total recovery of biological material, hence a better extraction of target organisms’ DNA. Thus, this study consisted of (a) an in vitro assessment involving spiking of the swabs with known amounts of amoebae and additional assessment of retrieval efficiency of amoebae from agar plates; (b) in vivo testing by swabbing of gill arches (second, third and fourth) of AGD-infected fish. Both in vitro and in vivo experiments identified an enhanced amoeba retrieval with Calgiswab® and Isohelix® swabs in comparison with cotton swabs. Additionally, the third and fourth gill arches presented significantly higher amoebic loads compared to the second gill arch. Results suggest that limiting routine gill swabbing to one or two arches, instead of all, could likely lead to reduced stress-related effects incurred by handling and sampling and a timelier diagnosis of AGD.     

Methacarn preserves mucus integrity and improves visualization of amoebae in gills of Atlantic salmon (Salmo salar L.)

Two aqueous fixation methods (modified Davidson's solution and modified Davidson's solution with 2% (w/v) Alcian blue) were compared against two non‐aqueous fixation methods (methacarn solution and methacarn solution with 2% (w/v) Alcian blue) along with the standard buffered formalin fixation method to (a) improve preservation of the mucous coat on Atlantic salmon, Salmo salar L., gills and (b) to examine the interaction between the amoebae and mucus on the gill during an infection with amoebic gill disease. Aqueous fixatives demonstrated excellent cytological preservation but failed to deliver the preservation of the mucus when compared to the non‐aqueous‐based fixatives; qualitative and semi‐quantitative analysis revealed a greater preservation of the gill mucus using the non‐aqueous methacarn solution. A combination of this fixation method and an Alcian blue/Periodic acid–Schiff staining was tested in gills of Atlantic salmon infected with amoebic gill disease; lectin labelling was also used to confirm the mucus preservation in the methacarn‐fixed tissue. Amoebae were observed closely associated with the mucus demonstrating that the techniques employed for preservation of the mucous coat can indeed avoid the loss of potential mucus‐embedded parasites, thus providing a better understanding of the relationship between the mucus and parasite.     

Evaluating the use of garlic (Allium sativum) for the remedy of Cryptocaryon irritans in guppies (Poecilia reticulata)

Garlic (Allium sativum) has been shown to possess antimicrobial properties against a range of disease‐causing agents, including fish parasites. Our study aimed to investigate the potential use of garlic as a treatment against Cryptocaryon irritans infection, using guppies (Poecilia reticulata) as the fish model. Garlic was freeze‐dried, powdered, and used as it is or as an aqueous extract. The content of allicin, its main active ingredient, was 1.25 mg/g in garlic powder and 0.82 mg/ml in the aqueous extract, as determined by HPLC analysis. Aqueous garlic extract fully immobilized C. irritans theronts and protomonts within 20 and 40 min, respectively, following exposure to 5 µl/ml. Treatment trials were performed, in which infected fish were fed with garlic powder‐supplemented feeds (5%, 10%, or 20% supplementation), bathed in garlic aqueous extract (250 or 500 µl/L) and subjected to a combined treatment which included both feeding and bathing. Results revealed that the tested treatments failed to cure the infection, though reduction in infection intensity on the caudal fin, but not on the gills, was evident following dietary supplementation with 20% of powdered garlic in one of the trials.     

C型肉毒梭菌肉毒毒素的提取与鉴定

[目的]通过对C型肉毒梭菌肉毒毒素的提取与鉴定,为类毒素和抗毒素的制备及抗原性分析奠定基础.[方法]将分离鉴定得到的C型肉毒梭菌通过扩大培养、产毒培养后将产生的肉毒毒素采用除菌过滤、硫酸铵盐盐析、离心、透析、浓缩的方法从产毒培养基中分离提取出来.再将提取的肉毒毒素通过SDS-PAGE鉴定毒素蛋白的分子量.[结果]分离出来的毒素蛋白重链和轻链分别在98和53 KDa左右,与C型肉毒毒素的理论分子量相符.[结论]提取的肉毒毒素是C型肉毒毒素.     

Remote sensing and forest inventories in Nordic countries – roadmap for the future

The Nordic countries have long traditions in forest inventory and remote sensing (RS). In sample-based national forest inventories (NFIs), utilization of aerial photographs started during the 1960s, satellite images during the 1980s, laser scanning during the 2000s, and photogrammetric point clouds during the 2010s. In forest management inventories (FMI), utilization of aerial photos started during the 1940s and laser scanning during the 2000s. However, so far, RS has mostly been used for map production and research rather than for estimation of regional parameters or inference on their accuracy. In recent years, the RS technology has been developing very fast. At the same time, the needs for information are constantly increasing. New technologies have created possibilities for cost-efficient production of accurate, large area forest data sets, which also will change the way forest inventories are done in the future. In this study, we analyse the state-of-the-art both in the NFIs and FMIs in the Nordic countries. We identify the benefits and drawbacks of different RS materials and data acquisition approaches with different user perspectives. Based on the analysis, we identify the needs for further development and emerging research questions. We also discuss alternatives for ownership of the data and cost-sharing between different actors in the field.