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采用冰冻切片、组织学染色及扫描电镜的方法对绿鳍马面鲀(Thamnaconus septentrionalis)鱼皮组织结构进行研究。结果显示,绿鳍马面鲀鱼皮由表皮层、鳞片层、真皮层和皮下组织层构成,并据此绘制绿鳍马面鲀鱼皮组织结构模式图。表皮层由上皮细胞和基底细胞组成,其厚度为(26.81±7.48) μm;鳞片层由锥状骨质凸起和基板组成,基板厚度为(22.49±5.19) μm,基板上不均匀地分布2~4行直径大小不一、顶端弯曲程度不同、高度为(257.13±10.41) μm的锥状骨质凸起;真皮层厚度为中部>头部>尾部,平均厚度为(176.97±21.11) μm,主要由胶原纤维构成;皮下组织层主要由胶原纤维和非纤维间质构成。本研究可为开发利用绿鳍马面鲀鱼皮资源提供基础资料。 相似文献
3.
扬子鳄胚胎背部皮肤及鳞甲的发生 总被引:1,自引:0,他引:1
本文观察了16例不同时间的扬子鳄(Alligatorsinensis)胚胎背部皮肤及鳞甲的形态及组织发生过程。孵化第20天,来自胚胎中胚层生皮节的间充质细胞开始向原始表皮下迁移,表皮仅具周皮层与生发层两层细胞。第28天背部鳞片开始明显,左右鳞片之间出现很浅的鳞间沟,前后鳞片交界处的原始表皮、真皮层开始向外突出形成鳞甲原基。第34天鳞甲原基突出伸长,第40天背鳞的纵崤明显。第34~50天中,鳞甲后缘基部的表皮层向鳞甲前缘基部的真皮层不断内陷,鳞甲显著伸长并向体后方水平伸出。背部表皮在孵化第34天出现三层细胞,第40天周皮细胞中开始出现色素沉集。第50天表皮具四层细胞,周皮层细胞中出现大量色素沉集。第60天表皮分层与成体时相似,周皮层已退化。孵化第34天真皮层细胞形态出现多样化,第40天真皮可分上、下两层。第50天真皮上层中形成交织的胶原纤维网,下层中形成平行走向的胶原纤维。本文简要讨论了扬子鳄鳞甲的形态发生特点。 相似文献
4.
Cephalosporins form a large group of β-lactam antibiotics which are used extensively in human medicine and to a lesser extent in domestic animals. In veterinary dermatology, the principle use for the cephalosporins is the clinical management of canine pyoderma associated with Staphylococcus intermedius . In practice, the use of orally administered first generation cephalosporin drugs to affected dogs is well tolerated and highly efficacious. Bacterial drug resistance appears to occur rarely. 相似文献
5.
试验为探究海狸色獭兔与皱襞型獭兔不同交配组合生产性能比较,随机选取6~7月龄健康皱襞型獭兔和海狸色獭兔各40只(30只母兔和10只公兔),进行不同交配组合试验,分别为海狸纯繁组(海狸色獭兔(♂)×海狸色獭兔(♀))、皱襞纯繁组(白色皱襞型獭兔(♂)×白色皱襞型獭兔(♀))、正交组(海狸色獭兔(♂)×白色皱襞型獭兔(♀))和反交组(白色皱襞型獭兔(♂)×海狸色獭兔(♀)),测定母兔繁殖性能和后代生长性能、屠宰性能及被毛品质。结果显示:正交组初生窝重320.71 g、产仔数6.71只、泌乳力1 727.43 g、仔兔断奶成活率83.91%、仔兔断奶窝重5 304.14 g、幼兔料重比4.06、屠宰率62.43%、皮张面积1 160.20 cm2、被毛密度15 951.70根/cm2、被毛细度16.32 μm、粗毛率6.83%;反交组初生窝重315.14 g、产仔数6.52只、泌乳力1 710.00 g、仔兔断奶成活率80.19%、仔兔断奶窝重4 814.82 g、幼兔料重比4.30、屠宰率62.93%、皮张面积1 172.20 cm2、被毛密度16 092.01根/cm2、被毛细度16.43 μm、粗毛率6.78%,经比对两组间差异均不显著(P>0.05);而海狸色纯繁组的初生窝重、产仔数、泌乳力、仔兔断奶成活率、仔兔断奶窝重、皮张面积、被毛密度、被毛细度均较皱襞型纯繁组低、而幼兔料重比、屠宰率及粗毛率均较皱襞型纯繁组高,经比对两个纯繁组间除料重比、屠宰率、被毛细度和粗毛率差异不显著外(P>0.05),其他各指标差异均显著(P<0.05)。综上所述,正交组合亲代的繁殖性能及F1代的生长性能和屠宰性能均略好于反交组合;而反交组合F1代的被毛品质略好于正交组合。 相似文献
6.
Over a 6-year period seven adult horses of different breeds and genders developed multifocal, exudative, oozing dermatitis characterized histologically by epidermal spongiotic vesicles and perivascular eosinophilic, neutrophilic and mixed mononuclear inflammation. Three horses were pruritic. Systemic disease was not noted. Two horses had a history of recurrent urticaria (hives) and one horse had nodules or welt-type lesions that progressed to exudative, oozing lesions. Interepithelial immunoglobulin (Ig)G was detected by avidin-biotin complex-peroxidase staining, but the pattern of staining was more consistent with epithelial oedema than specific IgG deposition associated with pemphigus. The exudative oozing lesions developed under circumstances suggesting that dermal oedema progressed to intracellular and intercellular epidermal oedema, which in turn progressed to the spongiotic vesicular epidermal lesions. 相似文献
7.
Ji-young Jung Eui-hwa Nam Seol-hee Park Seung-hee Han Cheol-yong Hwang 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(2):199-205
In humans, skin barrier dysfunction is thought to be responsible for enhanced penetration of allergens. Similar to conditions seen in humans, canine atopic dermatitis (CAD) is characterized by derangement of corneocytes and disorganization of intercellular lipids in the stratum corenum (SC) with decreased ceramide levels. This study was designed to evaluate the effects of a moisturizer containing ceramide on dogs with CAD. Dogs (n = 20, 3~8 years old) with mild to moderate clinical signs were recruited and applied a moisturizer containing ceramide for 4 weeks. Transepidermal water loss (TEWL), skin hydration, pruritus index for canine atopic dermatitis (PICAD) scores, and canine atopic dermatitis extent and severity index (CADESI) scores of all dogs were evaluated. Skin samples from five dogs were also examined with transmission electron microscopy (TEM) using ruthenium tetroxide. TEWL, PICAD, and CADESI values decreased (p < 0.05) and skin hydration increased dramatically over time (p < 0.05). Electron micrographs showed that the skin barrier of all five dogs was partially restored (p < 0.05). In conclusion, these results demonstrated that moisturizer containing ceramide was effective for treating skin barrier dysfunction and CAD symptoms. 相似文献
8.
针对兔皮生产周期长的特点,在传统兔皮鞣制技术的基础上,在脱脂工段加入适量的脱脂酶,将脱脂时间从原来的1h延长至8h,在跳过软化工序进行短时间浸酸后,次日进行铬鞣。结果表明,除能有效缩短加工时间、简化加工工艺外,该工艺加工的兔皮皮板柔软丰满,手感良好,收缩温度在99℃左右,证明这种短流程的兔皮鞣制工艺具有可行性。 相似文献
9.
G. Vichi I. Porcellato L. Mechelli G. Fantauzzo E. Razzuoli P. Modesto S. Mecocci C. Brachelente 《Equine Veterinary Education》2022,34(5):e193-e197
The present report describes a case of cutaneous papillomatosis related to equine papillomavirus type 2 (EcPV2) with concomitant cutaneous habronemiasis. A 2-year-old female Pura Raza Española horse was referred for a dermatological evaluation because of the onset of cutaneous multifocal, nodular lesions on the face characterised by a warty and partially ulcerated overlying epidermis. Multiple biopsies were taken from these lesions, and cutaneous viral papillomas with a concomitant severe focal eosinophilic dermatitis with intralesional Habronematidae nematode larvae were diagnosed. Immunohistochemistry revealed papillomaviral capsid protein L1 in the epidermal proliferative lesion, confirming the presence of a productive infection. Rt-qPCR confirmed the presence of EcPV type 2. To the authors’ knowledge, this is the first report of EcPV2-related papillomas with concurrent habronemiasis. 相似文献
10.
犬皮肤病是犬临床诊治中常见病之一。犬因品种、年龄、个体、营养、生活环境等不同而引起的皮肤病有很大的差异。本文就几种常见的犬皮肤病的不同的临床症状进行了简要综述,旨在给饲养者提供一些早期的、简单的鉴别及诊断,能尽快做出相应的预防和护理措施,并及时就诊。 相似文献