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991.
Equine herpesvirus-1 is a highly prevalent and frequently pathogenic infection of equids. The most serious clinical consequences of infection are abortion and equine herpesvirus myeloencephalopathy (EHM). In recent years, there has been an apparent increase in the incidence of EHM in North America, with serious consequences for horses and the horse industry. This consensus statement draws together current knowledge in the areas of pathogenesis, strain variation, epidemiology, diagnostic testing, vaccination, outbreak prevention and control, and treatment.  相似文献   
992.
Objective – To describe a case of Dieffenbachia ingestion in a dog presented for dysphagia and airway obstruction successfully treated with a temporary tracheostomy and supportive care beyond that reported in the veterinary literature. Case Summary – An 8‐year‐old male neutered Labrador Retriever, weighing 30 kg, was presented with the complaint of choking and gagging. Abdominal radiographs showed that he had a distended stomach full of foreign material and a gastrotomy was performed. After receiving preanesthetic medication, the dog developed inspiratory stridor and during anesthetic induction, marked oropharyngeal swelling complicated tracheal intubation. During surgery a large amount of dog bedding and Dieffenbachia plant material was removed. Because of the severity of the oropharyngeal swelling, the dog required a temporary tracheostomy and treatment for an acute allergic reaction related to the Dieffenbachia ingestion. The patient was discharged after 6 days in the hospital and had no significant complications. New or Unique Information Provided – To our knowledge, this is the first reported case of successful treatment of an airway obstruction related to the toxicity of Dieffenbachia ingestion.  相似文献   
993.
白鲫消化系统胚后发育的组织学研究   总被引:11,自引:0,他引:11       下载免费PDF全文
用连续石蜡切片方法对全长5~155mm的白鲫消化系统胚后发育进行了光镜观察,描述了其仔鱼、稚鱼、幼鱼摄食器官、消化器官发育的组织结构特征;讨论了腭褶、鳃耙侧突起胚后发育的组织结构特点在摄食中的作用及消化系统胚后发育的组织结构特点同摄食方式和食性转化的关系。  相似文献   
994.
Under experimental challenges, the gastrointestinal (GI) tract of fish has been proposed as an infectious route of several pathogenic bacteria. Is this also the case for diseased fishponds? A field research was conducted to verify this hypothesis. A crucian carp (Carassius carassius) reared fishpond with motile Aeromonas septicaemia outbreak was sampled in this study. A total of 62 strains of Aeromonas hydrophila were isolated and identified. The clonal relationship among these strains was determined by sequencing the gyrB gene, ERIC‐PCR, RAPD‐PCR, and the presence of seven virulence genes. Strains with identical genotypes were further confirmed as the same clone by multilocus sequence typing analysis. Experimental infection assays were also conducted in zebrafish (Danio rerio). The results show that the same clone strains identical to those in the blood of diseased fish existed in the intestinal digesta of diseased and uninfected fish. Regardless of their origins, all these strains were highly pathogenic to zebrafish. The result indicates that pathogenic strains of A. hydrophila had existed in the GI tract of fish before the infection occurred. This increases our knowledge on infectious route of A. hydrophila in crucian carp.  相似文献   
995.
对3种淡水有胃鱼的消化系统进行了比较解剖观察。描述了与摄食有关的齿、咽喉齿、舌和鳃耙的形态学特征;测量了体长、头长、吻长、口裂宽、口腔长。对几种鱼胃的形态、幽门盲囊、肝、胰脏、胆囊进行了描述;测量了食道长、胃长、胃直径、肠长、消化道长和腹腔长;并计算了有关比值。探讨了摄食习性与消化系统形态结构特点之间的关系。  相似文献   
996.
谷氨酰胺是猪体内最丰富的非必需氨基酸,能够抑制肠细胞凋亡、促进增殖发育维持肠道正常结构,最近研究发现谷氨酰胺促进肠粘膜细胞抗凋亡基因、增殖基因和细胞因子生成可能是其维持肠道正常功能的机制之一。本文综述了谷氨酰胺在肠道中的作用及其机制,并提出了今后研究的方向。  相似文献   
997.
巨魾的生物学特性初步研究   总被引:3,自引:1,他引:3  
对巨魾(Bagarius yarrelli Sykes)栖息江河进行实地调查了解,并解剖61尾体长20.4-43.5cm、体重124—1200g的野生巨魾研究其内脏器官特点,还对野生活体巨魾进行人工驯养研究。研究了解了巨魾外部形态结构特征和消化系统的组成;计算肠长与体长比值为1.19;确定巨魾食性为底栖肉食性鱼类。  相似文献   
998.
The aim of the present study was to evaluate the effects of three formulated diets: wheat‐gluten‐protein‐based diets supplemented with Lys‐Gly dipeptide (LG) or free lysine and glycine (FL), a control diet without lysine supplementation (C) and commercial starter Bio Oregon (BO) for on the growth and digestive system morphology of yellow perch. After 48 days of experimental feeding, fish fed LG diet showed the highest body mass. Fish fed LG diet showed the highest number of gastrin/cholecystokinin positive cells and the lowest number of CD3‐positive cells. The brush border of anterior intestine was the most PepT1 immunopositive in fish fed LG diet, the weakest in fish fed C diet. The largest hepatocytes were observed in fish fed BO, while the smallest in those fed FL diet, the difference being statistically significant. Relative hepatocyte cytoplasm volume occupied by lipids was higher in fish fed BO and FL compared to those fed C and LG. Number of proliferating cell nuclear antigen‐positive hepatocyte nuclei did not significantly differ among experimental groups. These results indicate that wheat‐gluten‐protein‐based diets supplemented with dipeptide Lys‐Gly (LG) were appropriate for yellow perch.  相似文献   
999.
将海洋红酵母(Rhodotorula sp.) C11以104、105和106 CFU/g饵料添加到基础饵料中,每一剂量组设3个平行,每一平行50头幼参,用100 L塑料桶进行30 d静水充气养殖试验。试验期间每日投饵1次,投喂量为幼参体重的5%。投喂试验结束后,评估其对幼参消化酶及免疫反应的影响。结果显示,与对照组比较,投喂海洋红酵母C11 104、105 CFU/g,显著提高了幼参肠道胰蛋白酶活力(P<0.05);投喂海洋红酵母C11 104 CFU/g,显著增加淀粉酶活力(P<0.05)。投喂海洋红酵母C11 105 CFU/g,幼参体腔细胞的吞噬活力显著高于对照组(P<0.05)。与投喂基础饵料的幼参比较,投喂海洋红酵母C11 105、106 CFU/g,幼参具有较高的体腔液溶菌酶(LSZ)活力(P<0.05)。投喂海洋红酵母C11 104 CFU/g,幼参具有较高的体腔细胞裂解液(CLS)LSZ活力(P<0.05)。投喂海洋红酵母C11 104 CFU/g,幼参体腔液总一氧化氮合酶(T-NOS)活力显著增加(P<0.05),投喂海洋红酵母C11 104、105、106 CFU/g,幼参CLS的T-NOS活力显著提高(P<0.05)。本研究表明,饵料补充海洋红酵母C11可促进幼参的消化酶活力和免疫反应。  相似文献   
1000.
为探究福寿螺(Pomacea canaliculate)能否有效利用草鱼(Ctenopharyngodon idellus)摄食水葫芦(Eichhornia crassipes)后产生的粪便,该研究对草鱼粪便、水葫芦饵料处理组福寿螺的生长、体组成、消化酶活力、氮磷富集量等进行比较分析。结果显示:1)两组福寿螺体质量均极显著增加(P<0.01),其中水葫芦组特定生长率(SGR)、食物转化率(FCR)均极显著高于草鱼粪便组(P<0.01);成活率(SR)无显著差异(P>0.05);2)两组福寿螺软体部的体组成差异不显著(P>0.05);3)水葫芦组的胃淀粉酶活力显著高于草鱼粪便组(P<0.05),纤维素酶、脂肪酶活力无显著差异(P>0.05);4)两组福寿螺均能有效富集氮(N)、磷(P)元素,且两组间无显著差异(P>0.05)。结果表明福寿螺摄食草鱼粪便不仅能满足螺本身的基本生长需求,还能间接减轻水体中的N、P负荷,表明在已有的“水体-水葫芦-草鱼”养殖模式中,可利用福寿螺解决草鱼粪便污染问题。  相似文献   
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