Evaluation of the Leishmania recombinant K39 antigen as a diagnostic marker for canine leishmaniasis and validation of a standardized enzyme-linked immunosorbent assay

Canine infections with Leishmania infantum are important as a cause of serious disease in the dog and as a reservoir for human visceral leishmaniasis (VL). Accurate diagnosis of canine infections is essential to the veterinary community and for VL surveillance programs. A standardized ELISA using a purified recombinant antigen (rK39) specific to VL was compared to the immunofluorescent antibody test (IFAT) as the standard. The ELISA was developed, optimized and evaluated using sera from 6368 dogs. The standardized ELISA and IFAT results were highly concordant. The timing and pattern of ELISA and IFAT seroconversion in dogs followed prospectively after natural infections were very similar. Antibodies reacting with rK39 were more common in asymptomatic canine infections than reported for subclinical human VL. The rK39 ELISA is a relatively simple and rapid assay for assessing the infection status of dogs, and is an alternative to IFAT, especially when screening large numbers of samples.     

豆瓣菜种质资源遗传多样性的RAPD和ISSR分析

以8个豆瓣菜的品种为试材，用筛选出的79个RAPD引物和34个ISSR引物对这8个品种的基因组DNA进行扩增，分别扩增出361条和179条谱带，每个引物扩增出的带在3～10条之间，平均每个引物扩增出约5条带。根据所得的条带进行聚类分析，两种标记产生的聚类图存在一些差异，但它们都可以较好地将8个品种按亲缘关系的远近划分为3个不同的类群。Mantel测试得出相关系数r=0．58155，表明RAPD和ISSR两种分子标记技术的相关度很低。     

Evaluation of the adverse effects of oral firocoxib in healthy dogs

This study evaluated the adverse effects of oral firocoxib in dogs. Six dogs (20.2+/-6.3 kg) were studied. Values for complete blood count (CBC), serum urea, creatinine, alanine transaminase, alanine phosphatase, gamma-glutamyl transferase, occult blood in feces, platelet aggregation, and buccal mucosal bleeding time were measured before and 7, 14, 21, and 29 days after SID treatment with firocoxib 5.3+/-0.34 mg/kg (FG) or lactose 1 mg/kg (LG) for 28 days, in a randomized crossover study. Gastrointestinal (GI) tract endoscopy was performed before treatment began and at 29 days. Lesions were scored from grade 0 to 6. Data were analyzed using anova and paired t-tests (P<0.05). None of the dogs presented adverse clinical effects. There were no significant changes in CBC, biochemical profiles within groups, or differences between groups. Pretreatment mean+/-SD bleeding time (LG, 70.7+/-32.1 sec; FG, 75.8+/-38.1 sec) and platelet aggregation (LG, 86.4+/-10.2%; FG, 85.6+/-9.2%) were not significantly different from readings at 29 days (LG, 95.2+/-25 sec; FG, 91.7+/-24 sec and LG, 73.2+/-15.1%; FG, 84+/-10.3%) nor the groups were different. None of the dogs had positive fecal occult blood tests, and endoscopic lesion scores were grade 0 both before treatment and at 29 days. Administration of firocoxib did not cause any adverse effects on GI, or hematological or serum biochemical variables and appears to have been well tolerated by dogs.     

A study of the effect of hemorrhage on the cardiorespiratory actions of halothane, isoflurane and sevoflurane in the dog

OBJECTIVE: To compare the cardiorespiratory changes induced by equipotent concentrations of halothane (HAL), isoflurane (ISO) and sevoflurane (SEVO) before and after hemorrhage. STUDY DESIGN: Prospective, randomized clinical trial. ANIMALS: Twenty-four healthy adult dogs weighing 15.4 +/- 3.4 kg (mean +/- SD). METHODS: Animals were randomly allocated to one of three groups (n = 8 per group). In each group, anesthesia was maintained with 1.5 minimum alveolar concentration of HAL (1.3%), ISO (1.9%) and SEVO (3.5%) in oxygen. Controlled ventilation was performed to maintain eucapnia. Cardiorespiratory variables were evaluated at baseline (between 60 and 90 minutes after induction), immediately after and 30 minutes after the withdrawal of 32 mL kg(-1) of blood (40% of the estimated blood volume) over a 30-minute period. RESULTS: During baseline conditions, ISO and SEVO resulted in higher cardiac index (CI) than HAL. Heart rates were higher with SEVO at baseline, while mean arterial pressure (MAP) and mean pulmonary arterial pressure did not differ between groups. Although heart rate values were higher for ISO and SEVO after hemorrhage, only ISO resulted in a higher CI when compared with HAL. In ISO-anesthetized dogs, MAP was higher immediately after hemorrhage, and this was related to better maintenance of CI and to an increase in systemic vascular resistance index from baseline. CONCLUSIONS: Although the hemodynamic responses of ISO and SEVO are similar in normovolaemic dogs, ISO results in better maintenance of circulatory function during the early period following a massive blood loss. CLINICAL RELEVANCE: Inhaled anesthetics should be used judiciously in animals presented with blood loss. However, if an inhalational agent is to be used under these circumstances, ISO may provide better hemodynamic stability than SEVO or HAL.     

Deforestation and Cultivation with Maize (Zea mays L.) has a Profound Effect on the Bacterial Community Structure in Soil

In this study, the effect of deforestation and cultivation of maize (Zea mays L.) on the physicochemical characteristics and the bacterial community structure in soil were studied at the national park Área de Protección de Flora y Fauna Nevado de Toluca in Mexico. Soil was sampled from three forested areas in the national park, from three deforested areas grazed by animals and from three areas cultivated with maize. The soil was characterized chemically and biologically, whilst the bacterial community structure was investigated through 454 pyrosequencing of the 16S rRNA gene. The pH in the forest soil decreased from 6·1 to 5·3 in the maize‐cultivated soil, whilst the soil organic C content decreased 1·4 times in the arable soil compared with the forest soil. The microbial biomass C decreased 2·9 times in the arable soil compared with the forest soil, but the metabolic quotient qCO₂ (ratio basal respiration to microbial biomass C) nearly doubled. Deforestation and maize cultivation reduced the abundance of Proteobacteria, Actinobacteria and Bacteroidetes, whereas Acidobacteria, Chloroflexi, Gemmatimonadetes and Firmicutes were resistant to these changes. It was found that soil characteristics were affected negatively by deforestation and nearly half of the organic matter was lost, and on these sloped fields, erosion will be high, further decreasing soil fertility. Although the relative abundance of a number of bacterial groups was reduced by deforestation, others were not affected by land‐use change. Copyright © 2014 John Wiley & Sons, Ltd.     

Evaluation of adverse effects of long-term oral administration of carprofen, etodolac, flunixin meglumine, ketoprofen, and meloxicam in dogs

OBJECTIVE: To evaluate adverse effects of long-term oral administration of carprofen, etodolac, flunixin meglumine, ketoprofen, and meloxicam in dogs. ANIMALS: 36 adult dogs. PROCEDURES: Values for CBC, urinalysis, serum biochemical urinalyses, and occult blood in feces were investigated before and 7, 30, 60, and 90 days after daily oral administration (n = 6 dogs/group) of lactose (1 mg/kg, control treatment), etodolac (15 mg/kg), meloxicam (0.1 mg/kg), carprofen (4 mg/kg), and ketoprofen (2 mg/kg for 4 days, followed by 1 mg/kg daily thereafter) or flunixin (1 mg/kg for 3 days, with 4-day intervals). Gastroscopy was performed before and after the end of treatment. RESULTS: For serum gamma-glutamyltransferase activity, values were significantly increased at day 30 in dogs treated with lactose, etodolac, and meloxicam within groups. Bleeding time was significantly increased in dogs treated with carprofen at 30 and 90 days, compared with baseline. At 7 days, bleeding time was significantly longer in dogs treated with meloxicam, ketoprofen, and flunixin, compared with control dogs. Clotting time increased significantly in all groups except those treated with etodolac. At day 90, clotting time was significantly shorter in flunixin-treated dogs, compared with lactose-treated dogs. Gastric lesions were detected in all dogs treated with etodolac, ketoprofen, and flunixin, and 1 of 6 treated with carprofen. CONCLUSIONS AND CLINICAL RELEVANCE: Carprofen induced the lowest frequency of gastrointestinal adverse effects, followed by meloxicam. Monitoring for adverse effects should be considered when nonsteroidal anti-inflammatory drugs are used to treat dogs with chronic pain.     

甜瓜种质资源苗期抗白粉病鉴定

在明确甜瓜白粉病生理小种的基础上,对从国内外搜集的109份甜瓜种质材料进行苗期接种鉴定。子叶展平后,采用孢子悬浮液法接种S.fuliginea属的2F小种,接种12～15d充分发病后开始调查抗感反应。鉴定结果显示,供试甜瓜种质中,高抗材料19份,中抗材料37份,中感材料33份,感病材料20份。抗病材料中有6份美国的厚皮甜瓜,1份法国厚皮甜瓜,2份日本厚皮甜瓜,2份中国薄皮甜瓜。研究将为改良甜瓜白粉病抗性和甜瓜抗病育种提供有潜在利用价值的基因资源和基本技术支持。     

不同连作年限土壤对大棚黄瓜根系活力及光合速率的影响

分别以大棚黄瓜连作４,２５年的土壤为处理,以露地菜田非连作土壤为对照进行盆栽黄瓜试验,研究不同连作年限土壤对黄瓜根系活力、光合速率及产量的影响,结果表明,连作２５年土壤栽培的黄瓜与连作４年土壤栽培的黄瓜根系活力、光合速率及产量均有显著差异,连作４年土壤栽培的黄瓜根系活力、光合速率及产量均高于连作２５年土壤栽培的黄瓜,而连作２５年１４年土壤栽培的黄瓜与对照相比均无显著差异。     

绵羊在澳大利亚的引进和传播

在欧洲白人到达之前,澳大利亚并没有畜牧业,土著人也没有饲养牲畜。1788年,英国“第一舰队”抵达植物湾,不仅带来了大量农作物,随船还带有羊、牛、猪等若干家畜,这些家畜成为澳大利亚早期畜牧业的基础。后经麦克阿瑟、佩平等优秀养羊者的改良培育,外加优越的放牧条件和科研配种技术的投入,羊毛业有了飞速发展,大量羊毛出口成为促进澳大利亚19世纪经济增长的重要原因,其副业羊肉生产也得益于冷冻技术的应用而有所发展。迄今澳大利亚已发展为现代农牧业最为发达的国家之一,羊群总数及羊毛产量稳居世界第一,特别是澳洲美利奴羊毛,更是享誉世界。故旧大陆绵羊的传入,不仅是家畜的传播,更是新旧大陆农业文明交流的重要结晶,对澳大利亚畜牧业产生了不可估量的重大影响。     

日光节能温室不同温度对黄瓜产量及其生理指标影响的研究

本试验采用三种温度处理,研究黄瓜产量、转化酶、IAA、叶绿素变化规律.结果表明不同处理的产量存在极显著差异.结瓜期各个处理IAA、转化酶、叶绿素变化趋势基本一致,在含量和活性上存在差异,基本趋势是C处理大于B处理,B处理大于A处理.