Genetic Introgression Between Arctic Charr (Salvelinus Alpinus) and Brook Trout (Salvelinus Fontinalis) in Bavarian Hatchery Stocks Inferred from Nuclear and Mitochondrial DNA Markers

Nuclear insulin-like growth factor 2 gene (IGF-2), growth hormone 1 gene (GH-1) and internal transcribed spacer 1 (ITS-1) of the ribosomal DNA as well as the mitochondrial NADH-3 and NADH-4 dehydrogenase genes (ND-3/4) exhibited species-specific restriction fragment patterns and three microsatellite loci (Sfo18, Ssa85 and Ssa197) had non-overlapping allele size ranges in Arctic charr and brook trout and were used as diagnostic markers for testing genetic purity of hatchery stocks and wild populations of Arctic charr and brook trout in Bavaria, Germany. Screening of four wild populations (three in Arctic charr and one in brook trout) revealed only a single hybrid (back-cross to brook trout) individual in L. Starnberg. In contrast, in three (out of five) hatchery stocks of Arctic charr and in both hatchery stocks of brook trout hybrids were detected with the frequency from 3 to 100%. Three hatchery stocks (SS2, SA and BS1) represent a hybrid swarm because they contained a very high proportion of hybrids (from 83 to 100%) and most or all hybrid individuals had alien alleles at only one or a few of six unlinked diagnostic loci, indicating that post-F₁ hybrids represent the majority of individuals in these stocks and introgression has taken place. Release or escape of introgressed individuals from hatcheries into natural water bodies should be avoided in order to protect the biological diversity and genetic integrity of native fish populations.     

承德市坝上高原典型土壤的系统分类研究

中国土壤分类尚处于发生分类占主体、系统分类快速发展的并用阶段。为了解承德市坝上高原典型土壤在中国土壤系统分类中的归属,本文在该区域栗钙土、灰色森林土、黑土等发生分类土壤类型区,挖取8个具有典型代表性的土壤剖面,进行土壤形成条件调查,并分层取样进行理化性状分析。结果发现：（1）8个土壤剖面具有的诊断表层有：有机表层、暗沃表层、淡薄表层;诊断表下层有：钙积层、雏形层;诊断特性有：半干润土壤水分状况、湿润土壤水分状况、滞水土壤水分状况、潮湿土壤水分状况、冷性土壤温度状况、纤维有机土壤物质、半腐土壤有机物质、潜育特征、氧化还原特征、盐基饱和度。（2）按照《中国土壤系统分类检索（第3版）》,8个土壤剖面归属为3个土纲（雏形土、有机土、新成土）、4个亚纲、5个土类、6个亚类。按照《中国土壤分类系统》,8个土壤剖面归属为5个土纲、6个亚纲、7个土类、8个亚类。（3）8个土壤剖面在发生分类与系统分类中发生分异的分类级别存在明显差异,两种分类体系的不同分类级别之间关系较为复杂,并不呈简单的、一对一的对应关系。     

Analysis of sampling strategies to substantiate freedom from disease in large areas

In this paper, we deal with the strategies of surveys to substantiate freedom from disease for a certain territory. Infection might not be distributed homogeneously. So, a relatively high within-herd prevalence might be observed while the herd-level prevalence is lower. For this situation, we compare various two-stage sample strategies.

The calculation of appropriate sample sizes becomes quite complicated. The theoretical generalization of the hypergeometric distribution by Cameron and Baldock [Prev. Vet. Med. 24 (1998) 1] introduces a simple way to evaluate multi-stage sample sizes while regarding real-test properties. We demonstrate the theoretical foundations of these calculations. These principles open up the possibility of optimizing costs or other relevant variables, by choosing the appropriate sample strategy (each of which ensures the same -level for the first stage). In addition, we evaluate the statistical power of the complete strategies under consideration.

Furthermore, we apply our theoretical results to a data example of Brucella melitensis. We used the herd-size situation in Germany, characterized by many small sheep holdings and only a few large ones. The consequences of real-test properties on sample sizes and on the applicability of several strategies are discussed.     

Lameness Associated with Mineralization of the Central Tarsal Bone and a Small Osseous Cyst-Like Lesion in Two Sport Horses

The clinical features, response to local analgesia, and imaging findings of two mature sport horses with lameness associated with abnormal mineralization of the dorsal aspect of the central tarsal bone and a small osseous cyst-like lesion are described. Although the radiological findings and the lesions identified using magnetic resonance imaging were similar, the lameness characteristics and responses to perineural analgesia differed. One horse failed to respond to treatment and was retired. The second horse was humanely destroyed. Postmortem examination confirmed the presence of an osseous cyst-like lesion distal to the subchondral bone plate of the central tarsal bone and extensive dense cancellous bone extending one-half the dorsoplantar depth of the bone.     

Laboratory procedures for the diagnosis of gastrointestinal tract diseases of dogs and cats

An increasing number of laboratory tests are available for diagnosis of gastrointestinal tract diseases in dogs and cats. Use of these tests can lead to more accurate and rapid diagnoses. This review discusses laboratory tests, both new and old, and the role they currently play in the evaluation of animals presented with gastrointestinal problems. A minimum database helps assess the severity of the disorder, detect extra-gastrointestinal causes of problems and assists in formulating diagnostic and therapeutic plans.

Faecal examination remains one of the most important diagnostic procedures in the investigation of gastrointestinal problems. Zinc sulphate faecal flotation is an excellent routine screening technique for helminth and protozoal infections, including giardiasis. Rectal cytology can assist in the diagnosis of large bowel disorders. Interpretation of faecal immunodiagnostic tests is hampered by insufficient knowledge of test sensitivities and specificities. Routine faecal cultures are not warranted and faecal occult blood tests are rarely indicated.

Serum tests for gastric inflammation are now under development. The serum trypsin-like immunoreactivity test remains the gold standard technique for the diagnosis of exocrine pancreatic insufficiency. Breath hydrogen tests can be helpful in assessing the functional relevance of mild abnormalities in small-bowel biopsy specimens. Subnormal concentrations of serum cobalamin appear to be more specific indicators of gastrointestinal disease in cats than in dogs. Tests for small intestinal bacterial overgrowth remain controversial and assessment of gastrointestinal permeability has yet to prove its value in the diagnostic assessment of companion animals with gastrointestinal problems. Faecal alpha₁-protease inhibitor (α₁-PI) shows promise for the diagnosis of protein-losing enteropathy.     

Relationship Between Echocardiographic Measurements and Body Size in Horses

The objectives of this study were to evaluate the optimal body size variable, and to determine mathematical model that best fits echocardiographic measurements to body size in the equine species. One hundred fifty horses of various breeds, aged 1 week to 17 years, body weight (BW) 38-890 kg, and free from cardiac disease were used in this study. Based on their age (ie, younger or older than 2 years), animals were separated into two groups. In each horse, the BW, height at withers (HT), thoracic circumference (TC), and the body length were measured; the body surface area was calculated; and a standard two-dimensional and M-mode echocardiography was performed allowing classic cardiac measurements to be taken. Correlations between each echocardiographic measurement and each of the anthropometric variables were assessed via a Pearson's product-moment analysis and using linear, logarithmic, and power regression analysis in all animals and within the two groups. The dimensional, but not functional, echocardiographic measurements showed a close correlation with all body size variables, especially during growth. The relationship between cardiac measurements and body size was best described using power regression models with TC as the anthropometric variable, but the relationship was also very accurately described using BW, body surface area, or body length. In the equine species, dimensional echocardiographic reference values should be established using power regression equations on TC. Such a correction for body size could increase the diagnostic value of echocardiography in equine cardiology.     

Squamous cell carcinoma of the equine stomach

Summary

Both clinical and pathological features of seven horses suffering from a squamous cell carcinoma of the stomach are presented. The main complaints in the horses, aged six years or more, were loss both of weight and of condition. Metastases had often developed.

The diagnostic difficulties and possibilities are discussed.     

湘北地区典型水稻土的发生特性及其在中国土壤系统分类中的归属

选取湘北地区7个发育于2种母质的水稻土剖面样点,通过对其成土环境、剖面形态特征以及土壤理化性质进行野外观测和室内分析,按中国土壤系统分类方案,检索出诊断层和诊断特性,确定其在中国土壤系统分类中的归属,并评述土系的生产性能。结果表明:供试水稻土归属于水耕人为土亚纲下的简育和铁聚水耕人为土2个土类,底潜简育水耕人为土、普通简育水耕人为土、普通铁聚水耕人为土、漂白铁聚水耕人为土4个亚类;进一步按照土族和土系划分标准,划分出7个土族和7个土系。在相同成土环境下,同种母质发育的水耕人为土,土壤系统分类比土壤发生分类具有更强的划分能力。其划分的基层土壤单元(土族和土系),对农业生产、土地资源利用更具有指导意义。     

一次河北强降雪天气过程物理量诊断分析

利用Micaps、物理量场剖面及海岛自动站等同步资料,对2009年11月8～12日发生在河北区域性大暴雪高影响天气过程进行诊断分析。结果表明,大暴雪成因为3个不同时空尺度系统影响所致:8日降雨与强锋区弱切变南压及前期大雾抬升有关;9～10日暴雪是在天气尺度锋区的特定环流背景下,不同层面的温、湿场的"三支"气流辐合区恰好覆盖河北东部;11～12日中-大雪为环流快速调整后新生低槽东移所致;物理量诊断分析表明,9～10日石家庄地区强降雪时段850 hPa以下为下沉气流即升压降雪,渤海至太行山区偏东风和比湿大值区从8日持续到10日;11～12日新一轮低值系统垂直速度大值区中心为-10.0 hPa/h,12 h后倾45°,中心值为-7.0hPa/h,明显系统降雪时比湿中心高度达600 hPa,移到河北东部降雪时高度回落至700 hPa,与850 hPa的高比湿区形成上下叠加的形式,并随着系统快速东移入海,到20:00河套冷空气已进入太行山区西部降雪逐渐停止,低值系统迅速东移至华北东部出现中-大雪天气。华北东部降雪前渤海大于16 m/s偏东风维持时间大于18 h,950 hPa以下渤海中心区域主导风向水汽输送对强降雪落区动态变化具有指示意义;相对不同地区衍生的灾害性天气与持续降雪、持续低温及地形有关。     

利用多普勒雷达产品诊断分析雷雨大风

利用常规实况场、物理量场、雷达产品资料,对2007年7月30日河南省东北部出现的雷雨大风天气进行诊断分析。结果表明,造成这次强对流天气过程的原因是副高西北侧、槽前深厚的西南气流内产生的飑线发展东北移造成的;持续5 d的深厚低压槽前较强的西南急流,一方面把大量热量、水汽和动量向北输送,使当地具有大量的不稳定能量存储,为对流的发生提供了热力和动力条件,另一方面,高低空深厚一致的西南气流决定了雷雨大风的移动方向。雷达图上,2条回波带的合并形成的"人"字型回波使对流加强,雷雨大风最大风速出现在"人"字型回波顶端及其移动路径上;根据多普勒雷达风廓线上风场的突然上传,可以提前35 min预报雷雨大风天气。