清远市肿眼肉鸡病原诊断和药敏试验

广东省清远地区3群肉鸡临床表现不同程度的肿眼、流鼻水等症状,临床治疗处理效果不理想。在3群病鸡中各取病鸡鼻窦腔分泌液进行细菌分离培养、革兰氏和瑞氏染色,并对分离菌株进行了玻片凝集和生化试验。结果表明,革兰氏染色呈阴性,瑞氏染色呈蓝色,油镜下可见细菌呈短杆菌或球杆菌,两极着色,3群分离株均与副鸡嗜血杆菌A型血清完全凝集反应,与B和C型血清无凝集反应,确定肿眼肉鸡病原为A型副鸡嗜血杆菌。同时选用多种药物研究了该病原菌的药敏性,结果显示,A型副鸡嗜血杆菌对头孢噻呋、氟苯尼考和青霉素3种药物均表现极敏。     

2019—2020年河南省小麦茎基腐病病原菌鉴定及致病力测定

为监测小麦茎基腐病病原菌的变化,2019—2020年自河南省安阳、濮阳和鹤壁等17个市129个采样点采集小麦茎基腐病病株样品并分离病原菌,对所有分离物进行形态学鉴定,利用特异性引物、ITS和EF-1α基因序列进行分子生物学鉴定,并于室内对优势病原菌菌株进行致病力测定。结果表明,共分离得到892株镰孢菌Fusarium分离物,所得分离物中假禾谷镰孢F. pseudograminearum共851株,所占比例为95.41%,为优势种;禾谷镰孢F. graminearum共16株,所占比例为1.79%。除信阳市外,其他16个市优势病原菌均为假禾谷镰孢。不同假禾谷镰孢菌株存在明显的致病力分化,但多数为强致病力菌株。     

Population Dynamics of Biocontrol Agents and Pathogens in Soils and Rhizospheres

Understanding the dynamics between a pathogen and a biocontrol agent (BCA) in soil or in an infection court such as the rhizosphere is crucial for predicting the success of biological control. This is especially true for biological control using the strategy of reduction of initial inoculum prior to infection. By studying the population density fluxes over time, one can observe how the BCA and pathogen influence each other's population and life cycles, and how the biological and physical environment influence this relationship. Methods for quantifying fungi and bacteria in soil, including classical (dilution plating, baiting, bioassays), immunological (ELISA, IFC, immunomagnetic) and molecular (DNA hybridization, PCR, marker and reporter genes) methods, are discussed and critiqued. Finally, the value of mathematical modeling of population dynamics as a means of providing important information about the tripartite relationship between the pathogen, BCA, and host plant is reviewed.     

传染性腺胃炎组织病理学和超微结构的研究

近两年来，我国的许多地区流行了一种以腺胃肿胀，生长严重受阴为特征的传染病－－传染性腺胃炎。对肿胀的腺胃组织进行组织学和超微结构的观察表明，腺上皮细胞以网状细胞组织增生为主，肿胀的细胞内有大量的空泡样结构，与马立克氏病、淋巴细胞白血病有明显的区别。朋腺胃组织的超薄切片中可观察到４种病毒颗粒，其中有３种业已证明分别为网状内上组织增生症病毒、冠状病毒和新城疫病毒，另一种病毒呈球形，大小在６０￣８０ｎｍ，     

The current status of antibiotic use in equine reproduction

Antibiotics are infused into the uterine lumen, added to semen extenders and given systemically for infections of the reproductive tract of the mare and stallion. Evidence‐based guidelines for determining treatment length and route of administration are limited and use is frequently based on convenience or tradition. Current recommended antibiotic use for the treatment of bacterial and fungal endometritis, placentitis and metritis in the mare and genital infections of the stallion are presented. Antibiotic classes used for reproductive problems are also reviewed.     

中华鳖常见疾病的诊断及其综合防治

结合常见的鳖病病原、病症,对PCR、核酸杂交及ELISA等快速诊断技术进行分析,寻找适合中华鳖病原的早期预警方法,进而探讨优良的中华鳖养殖管理模式及鳖病的综合防治方法,以期应用于生产,促进养鳖业的快速发展.     

樟子松叶枯病病原菌的初步研究

本文介绍了樟子松叶枯病病症的观察和病原菌的分离培养过程，对病原菌的形态、培养特性等进行了初步研究，经鉴定樟子松叶枯病病原子囊菌亚门、盘菌纲、星裂盘菌目、斑痣盘菌科、小散斑诉Ｌｏｐｈｏｄｅｒｍｅｌｌａｓａｌｃｉｇｅｎａ种。     

国外森林衰退病病原的若干概念

森林衰退病发生的原因，国外的学者对此有不同的见解，其致病因素也由单一因素发展到多种因素，因而在衰退病病原方面提出了若干的概念。该文就目前病原的几种概念进行简要叙述。     

片形吸虫病病原的研究概况

片形吸虫病是反刍动物的一种重要的寄生虫病之一，可引起严重的经济损失。近年来有关片形吸虫病病原的研究较为迅速，尤其是病原的种类以及病原代谢的研究更为热烈。本文将从病原的种类及分布、病原的糖类代谢、脂类代谢和蛋白质代谢作一简单概述。     

Effect of fungal toxins on germination of Striga hermonthica seeds

Fourteen fungal toxins were assayed in vitro to evaluate their effect on seed germination of the parasitic weed Striga hermonthica . Among them, T-2 toxin proved to be the most active, being able to inhibit 100% seed germination at 10⁻⁵ M, and being still active when tested at a concentration of 10⁻⁷ M (19% inhibition). Deoxinivalenol was also very active, causing 100% and 69% reduction in germination when assayed at 10⁻⁴ and 10⁻⁵ M respectively. Cytochalasin E, tenuazonic acid, fumonisin B₁, enniatin and nivalenol were shown to have an inhibitory effect of around 50% at 10⁻⁴ M, whereas other toxins had lower or no activity. The high activity shown by some fungal toxins suggests that they may have potential for use as more natural and safe herbicides to suppress parasite seed germination.