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41.
草履蚧Drosicha corpulenta(Kuwana)是北方园、林、果树上的重要害虫,而红瓢虫属Rodolia Mulsant的昆虫是其重要天敌。本文对北京园林植物上的三种红瓢虫(暗红瓢虫Rodolia concolor(Lewis)、红环瓢虫Rodolia limbata(Motschulsky)和浅缘瓢虫Rodolia ru- focincta(Lewis)进行研究,描绘了它们的外生殖器及鉴别特征,其中对浅缘瓢虫外生殖器的描述尚属首次。  相似文献   
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The present work was designed to investigate the microscopic structure of the oesophagus in the southern white-breasted hedgehog (Erinaceus concolor) using histochemical staining, Scanning electron microscope (SEM), and stereological procedures. Four adult males were included in our study. Serial sections of the entire length of the oesophagus were stained with aldehyde fuchsin, alcian blue (pH 2.5), Periodic acid Schiff (PAS), and Masson's trichrome. Then, the total volume of the oesophagus, and the total volume of its different layers, were estimated using Cavalieri's principle. The oesophageal epithelium was a non-keratinized stratified squamous type. Muscularis mucosa was present as a thick layer between lamina propria and submucosa and its thickness was increased toward the stomach. Tunica submucosa was a loose connective tissue containing an oesophageal gland with PAS-positive and AB-positive reactions throughout the submucosa and become denser toward the stomach. The tunica muscularis consisted of two distinct striated muscle layers, and its thickness was decreased toward the stomach. On SEM images, the cervical and thoracic oesophagus showed shallow folding, while the abdominal part had deeper folds. The present findings indicate that the histological properties of the oesophagus in southern white-breasted hedgehogs have slight similarities with rodents and considering its epithelium, submucosal glands and tunica muscularis more resemble with dog oesophagus. The obtained results may be quite helpful to improve the current knowledge of the histophysiology of the hedgehog gastrointestinal tract as a member of eulipotyplan mammals and as a pet for biologists and veterinarians.  相似文献   
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Abstract

Protease and trypsin-like activities of the digestive system of the tropical sierra Scomberomorus concolorwere evaluated. Sierra digestive tract extracts hydrolyzed specific substrates for trypsin, chymotiypsin, and leucine aminopeptidase At least eight bands of activity were observed by using SDS-PAGE. In PAGE and serineinhibition assays, one fraction resembled bovine trypsin. An ammonium sulfate (40-60%) trypsin-like fraction displayed different inhibitions with tosyllyschloromethyl ketone (96%) and soybean trypsin inhibitor (100%). Maximum activity was found using benzoyl-L-arginine-p-nitroanilide as substrate at pH 9.0 at 25°C and around 50°C at pH 7.8. The capacity of the trypsin-like fraction to work at different pHs (4, 7, and 9) at 25°C and different temperatures (0 and 40°C) at pH 7.8 were detected.  相似文献   
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Predation by feral cats (Felis catus) and red foxes (Vulpes vulpes) are key threatening processes for many endangered wildlife species. Toxin delivery through compulsive oral grooming is a potential mechanism to supplement existing control techniques for feral cats and red foxes, particularly when high prey densities reduce the uptake of toxic food baits by cats. We investigated the efficacy of different grooming traps by applying a gel containing toxic para-aminopropiophenone (PAPP) to the fur of feral cats and red foxes in experimental pens. Grooming behaviour and signs of poisoning in these animals were recorded by video. More cats interacted with “walk past” grooming traps triggered by sensor beams than with trap models that required the cat to enter a pipe or baited cage. After triggering a trap that had applied PAPP gel to their fur, 14 of 16 feral cats showed symptoms of anoxia, and 8 of these cats were dead by the following morning without exhibiting signs of distress. Seven of 12 foxes were observed to groom fur to which toxic gel had been applied and 3 of these ingested a lethal quantity of PAPP as a result. Our successful proof-of-concept trials support further development of grooming trap sensors and toxin delivery mechanisms to provide humane and targeted feral cat control, although this technique is unlikely to be as successful for fox control, given that foxes appear to not groom as fastidiously as cats.  相似文献   
47.
王云霞  张萍  葛蓓蕾  雅蓉  杨英  靳磊 《草业学报》2021,30(6):205-213
为探明钾素与渥丹百合生长发育及鳞茎活性成分积累的关系,采用Hoagland营养液浇灌技术,研究不同钾水平(K0、K1、K2、K3、K4)对渥丹百合株高、茎粗、叶片数、叶绿素含量的影响,采用分光光度法、火焰光度法测定并分析了鳞茎中活性物质(多糖、总酚、总黄酮、皂苷)及钾含量的积累.结果表明:1)渥丹百合农艺性状对钾水平的...  相似文献   
48.
渥丹百合种内花粉多样性研究   总被引:3,自引:0,他引:3  
应用光学显微镜和扫描电子显微镜对渥丹百合种内10个居群花粉的形态、大小、表面纹饰、生活力等性状进行了比较研究.结果表明,渥丹百合花粉皆呈椭球体,花粉大小差异不显著,花粉都具单萌发沟,沟长达两端,但不同变种的花粉网脊上基粒形状差异显著,网脊宽度/网眼直径(R/L值)表现为大花百合(L.concolor var.megalanthum Wang et Tang)最小,黄花渥丹(L. concolor var.concolor f.coridion Kitag.)最大.花粉生活力测定表明大花百合的花粉生活力较低.  相似文献   
49.
以有斑百合花粉为试材,通过离体培养,利用单因子试验研究蔗糖、硼酸、以及钙、镁、钾离子对花粉萌发和花粉管生长的影响.并在此基础上进行多因子试验比较了蔗糖、H3 BO3、CaCl2和Ca(NO3)2·4H2O对有斑百合花粉萌发的影响.结果表明:蔗糖、硼和钙对有斑百合花粉萌发影响较大,而钾和镁的影响较小;适宜的花粉培养液为蔗...  相似文献   
50.
美洲狮和亚洲黑熊蛔虫ITS序列扩增及序列分析   总被引:1,自引:1,他引:0  
以采自广州动物园美洲狮和亚洲黑熊体内的蛔虫样品为研究对象,提取样品的总DNA,以保守引物对核糖体DNA内转录间隔区(ITS)序列进行PCR扩增、测序及网上比对。结果表明,美洲狮体内样品获得与GenBankTM公布的狮弓首蛔虫相似性很高的ITS-1、ITS-2和5.8S序列,亚洲黑熊体内样品获得与GenBankTM公布的转移拜林蛔虫相似性很高的ITS-2序列,并首次获得样品的ITS-1与5.8S序列。序列分析结果表明,美洲狮体内蛔虫样品为狮弓首蛔虫,亚洲黑熊体内蛔虫样品为转移拜林蛔虫。  相似文献   
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