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211.
Subepiglottic cysts (SECs) are an infrequent cause of upper respiratory tract noise and exercise intolerance in horses. They may also be associated with no clinical signs and be an incidental finding during routine upper airway endoscopy. The aim of this study was to assess the effect on performance of horses undergoing surgical removal of SECs. The case records of 15 horses (1995–2009) diagnosed with SECs were retrieved. Eleven (73%) of the 15 horses included in the study were Thoroughbred racehorses. Eleven (73%) of the 15 horses had no preoperative clinical signs related to the SECs, with the remaining 4 (27%) having a respiratory noise (n = 4), nasal discharge (n = 1), difficulty swallowing (n = 1) or a cough (n = 1). Endoscopic examination in the standing horse was diagnostic in 93% (n = 14) of horses. Nine (82%) of the 11 Thoroughbred horses were yearlings, of which only one horse (11%) presented with clinical signs consisting of a respiratory noise and nasal discharge. Four of the 11 (36%) Thoroughbred horses were found to have concurrent epiglottic entrapment. Surgical removal was successful in all cases. Eight of the 11 (73%) Thoroughbred horses in this study raced following SEC removal. The majority of SECs are identified during routine endoscopic examinations and are not associated with clinical signs. The prognosis following surgical removal of SECs is good and future performance does not appear to be affected.  相似文献   
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松材线虫病的发生原因、危害症状及防治策略   总被引:1,自引:0,他引:1  
松材线虫病能够引起大面积松树出现枯死现象,对松树林产生毁灭性伤害,属于世界性病害。为了有效促进我国林业发展,需要对松材线虫病加强防治。而目前我国在防治松材线虫病过程中难度相对较大,防治技术也比较滞后,资金不足等问题导致难以高效控制松材线虫病。基于此,深入探究松材线虫病的发生原因、危害症状,并提出了有效的防治策略。  相似文献   
214.
乌尼尔  张晶  海棠 《草地学报》2019,27(3):589-595
为了探索放牧干扰对羊草(Leymus chinensis Tzvel)根际土壤小型动物-土壤线虫群落的影响规律,本试验以土壤线虫为生物指标对典型草原放牧区及围栏区羊草根际土壤线虫群落特征及区系进行了研究,结果表明:羊草根际共捕获34属线虫,放牧影响羊草根际线虫总数量及优势类群,不同土层土壤线虫总数量的分布规律为:围栏区>放牧区,放牧区优势及次优势类群中植物寄生线虫类所占比例明显高于围栏区。放牧区羊草根际土壤线虫Shannon多样性指数显著高于围栏区。放牧区瓦斯乐斯卡指数及自由生活线虫成熟度指数低于围栏区,说明放牧区土壤健康状况较差。放牧影响羊草根际土壤线虫区系的分布,放牧区0~10 cm,10~20 cm羊草根际土壤线虫区系分布在B区和D区,表明放牧区土壤线虫食物网相对于围栏区受干扰大、土壤线虫食物网不稳定,且退化。  相似文献   
215.
在病虫害防治过程中切断传染路径是重要的传统防治方法。松干线虫的主要传染媒介是松墨天牛,伐除病死木、熏蒸方法处理残余伐根、诱捕器捕杀天牛成虫3种方法相结合,处理染病林分,并和没有进行处理的林分进行比较,试验表明,染病个体植株数明显下降,松墨天牛虫口密度大幅度降低。基于这样的思路,设计了试验方案,收集大量数据,并进行数据处理分析,得出结论,为松干线虫的防治提供理论依据。  相似文献   
216.
This report describes bilateral mammary gland infection with a previously unidentified Cephalobus species of nematode. Only one previous case of verminous mastitis due to a Cephalobus species has been reported, pre-dating the widespread use of molecular diagnostics. This report describes the case presentation and management, as well as the morphological and molecular methods of nematode identification.  相似文献   
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218.
南方根结线虫是一种严重危害我国蔬菜安全生产的土传病害,生产上亟需一种有效的防控方法。本研究从根结线虫卵囊中分离到一株生防真菌NF-06,通过形态学和分子生物学方法将其鉴定为粉红螺旋聚孢霉Clonostachys rosea。通过离体活性测定的方法测定NF-06发酵滤液对根结线虫2龄幼虫的致死作用,发现24、48和72 h后2龄幼虫的相对死亡率分别达63.6%,75.5%和87.0%。以产孢量为指标,优化菌株NF-06固体发酵条件,确定最佳基础培养基为麦麸和麦秸秆混合物,其比例为4:1(wt/wt),在基础培养基中添加10%玉米粉、2%蚕豆粉和0.05% KH2PO4可获得最大产孢量;最优培养条件为初始pH值7.0,初始含水量40%,接种量5%,产孢量达8.9×1010 CFU/g。室内盆栽防治效果测定显示,菌株NF-06固体发酵物能够有效降低土壤中的线虫数量和番茄根结指数,其中5 g/株穴施处理的线虫减退率和防治效果分别达67.9%和69.6%。本研究为生物杀线虫剂的开发和利用提供理论依据。  相似文献   
219.
Benzimidazole (BZ) resistance is widespread in nematode parasites of livestock, but very little is known about the levels of BZ resistance in parasites with avian hosts. We investigated BZ resistance in Trichostrongylus tenuis, a nematode parasite of red grouse, Lagopus lagopus scotica. BZ anthelmintics had been in use in this system for up to 15 years, yet existing phenotypic evidence for resistance was inconclusive. We screened 1530 individuals from 14 populations at the principal β-tubulin locus for BZ resistance (isotype 1, residue 200) and 940 of these at two further resistance sites (isotype 1, residue 167; isotype 2, residue 200). No BZ resistant genotypes were found. Alternative mechanisms may be responsible for BZ resistance in this system, or the method and timing of treatments may reduce selection pressure for BZ resistance by creating substantial refugia for susceptible genotypes.  相似文献   
220.
Osseous cyst‐like lesions (OCLLs) were diagnosed by standing low‐field magnetic resonance (MR) imaging in 9 mature horses (age range 6–17 years). All horses had been subjected to a routine lameness evaluation (including standard foot radiographs) with no diagnosis being reached prior to MR imaging. The duration of lameness ranged from one month to one year. OCLLs were diagnosed in 12 feet. The site of the lesions included the distal phalanx in 11 feet (subchondral bone in 4, insertion of collateral ligaments of the distal interphalangeal joint in 4, insertion of the distal sesamoidean impar ligament in 3) and the subchondral bone of the distal aspect of the middle phalanx in one foot. OCLLs were characterised by discrete spherical or elliptical areas of high or intermediate signal in all MR sequences. In most cases the lesion was surrounded by a rim of bone with abnormally low signal.  相似文献   
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