Isolation of Streptococcus cuniculi from corneal lesion in laboratory-raised mice

Corneal lesions appearing as white mass beneath intact epithelium, with ocular discharge in one mouse, was observed in a batch of laboratory-raised BALB/c mice (n=9 of 56). The affected mice remained active, well-groomed and had normal appetite. Isolates recovered from swab cultures of the external and internal contents of the eye had partial 16S rRNA gene sequence of 99.1% similarity to Streptococcus cuniculi. No previous report of S. cuniculi infection in laboratory rodents has been presented. The isolate was susceptible to all antibiotics tested. We suggest S. cuniculi is an opportunistic bacteria in laboratory mice but are uncertain of its source. Our findings revealed that S. cuniculi is able to colonize laboratory mice and should be considered when mice present with eye lesion or ocular discharge.     

日粮中添加蛋氨酸锌对粤黄鸡繁殖性能和血浆中雌激素和孕酮水平的影响

将567只14周龄的粤黄母鸡分为7个组饲养于双层的种鸡笼中，各组饲以不同的日粮：I)对照组，饲喂无外源添加锌和蛋氨酸的玉米—豆粕型基础日粮；Ⅱ)饲喂添加氧化锌的相同基础日粮；Ⅲ)饲喂添加蛋氨酸的相同基础日粮；Ⅳ)饲喂按N．R．C标准配制的基础日粮；V)饲喂添加低剂量蛋氨酸锌的基础日粮；Ⅵ)饲喂添加中剂量蛋氨酸锌的基础日粮；Ⅶ)饲喂添加高剂量蛋氨酸锌的基础日粮．上述日粮中锌的水平分别为：30．09，70．09，30．09，70．09，78．69，97．19和134．20mg/kg．蛋氨酸的水平分别为：0．28％，0．28％，0．36％，0．36％，0．37％，0．38％和0．38％．实验表明：日粮中添加外源性的锌和蛋氨酸可影响母鸡的蛋质量、受精率、孵化率和血浆中孕酮和雌激素的水平，其中，锌水平分别为70．09，70．09和78．69mg／kg；蛋氨酸的水平分别为0．28％，0．36％和0．37％的第Ⅱ、第Ⅳ和第Ⅴ组，上述指标均显著高于对照组，但日粮中Zn和蛋氨酸的量高于78．69mg/kg和0．37％水平，对种鸡的受精率、孵化率、产蛋量以及血浆中孕酮和雌激素均无促进作用．     

Growth and nitrogen productivity of drip-irrigated winter wheat under different nitrogen fertigation strategies in the North China Plain

Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivum L.) production in the North China Plain (NCP).  Drip fertigation is considered to be an effective method for improving N use efficiency and reducing losses, while the performance of drip fertigation in winter wheat is limited by poor N scheduling.  A two-year field experiment was conducted to evaluate the growth, development and yield of drip-fertigated winter wheat under different split urea (46% N, 240 kg ha^–1) applications.  The six treatments consisted of five fertigation N application scheduling programs and one slow-release fertilizer (SRF) application.  The five N scheduling treatments were N0–100 (0% at sowing and 100% at jointing/booting), N25–75 (25% at sowing and 75% at jointing and booting), N50–50 (50% at sowing and 50% at jointing/booting), N75–25 (75% at sowing and 25 at jointing/booting), and N100–0 (100% at sowing and 0% at jointing/booting).  The SRF (43% N, 240 kg ha^–1) was only used as fertilizer at sowing.  Split N application significantly (P<0.05) affected wheat grain yield, yield components, aboveground biomass (ABM), water use efficiency (WUE) and nitrogen partial factor productivity (NPFP).  The N50–50 and SRF treatments respectively had the highest yield (8.84 and 8.85 t ha^–1), ABM (20.67 and 20.83 t ha^–1), WUE (2.28 and 2.17 kg m^–3) and NPFP (36.82 and 36.88 kg kg^–1).  This work provided substantial evidence that urea-N applied in equal splits between basal and topdressing doses compete economically with the highly expensive SRF for fertilization of winter wheat crops.  Although the single-dose SRF could reduce labor costs involved with the traditional method of manual spreading, the drip fertigation system used in this study with the N50–50 treatment provides an option for farmers to maintain wheat production in the NCP.     

Potential Antiviral Agents from Marine Fungi: An Overview

Biodiversity of the marine world is only partially subjected to detailed scientific scrutiny in comparison to terrestrial life. Life in the marine world depends heavily on marine fungi scavenging the oceans of lifeless plants and animals and entering them into the nutrient cycle by. Approximately 150 to 200 new compounds, including alkaloids, sesquiterpenes, polyketides, and aromatic compounds, are identified from marine fungi annually. In recent years, numerous investigations demonstrated the tremendous potential of marine fungi as a promising source to develop new antivirals against different important viruses, including herpes simplex viruses, the human immunodeficiency virus, and the influenza virus. Various genera of marine fungi such as Aspergillus, Penicillium, Cladosporium, and Fusarium were subjected to compound isolation and antiviral studies, which led to an illustration of the strong antiviral activity of a variety of marine fungi-derived compounds. The present review strives to summarize all available knowledge on active compounds isolated from marine fungi with antiviral activity.