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比目鱼是研究维生素A(Vitamin A,VA)对软骨组织发育影响的一个很好的动物模型,可供研究其潜在的形态变化、细胞分化、增殖以及基因表达调控。不同生命阶段(胚胎、幼虫、幼年或成年阶段)的软骨发育及体内稳态主要受视黄酸调控,其是VA的活性代谢物。鱼类不能合成VA,必须从日粮中摄入。因此,日粮中VA的失衡可能会改变VA的稳态,导致基因表达、骨细胞增殖和分化受到影响,最终导致骨骼畸形。骨骼畸形是影响比目鱼养殖生产效率和质量的重要因素之一。然而,不同种类的比目鱼在骨形成过程中表现出不同的发育时间,因此不同种类的比目鱼对VA的需求也可能不同。本文综述了日粮VA含量对比目鱼发育影响的研究现状,强调日粮VA失衡引起的骨骼畸形。 相似文献
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本研究进行6周的饲养试验,评估维生素E(VE)和汞对比目鱼生长性能和汞生物学蓄积的影响。试验采用2×3因子设计,将360条比目鱼随机分到6组,每组3个重复,每个重复20条鱼。对照组饲喂基础日粮,处理组分别在基础日粮中添加100、200 mg/kg VE、15 mg/kg汞、15 mg/kg汞+100 mg/kg VE、15 mg/kg汞+200 mg/kg VE。结果显示,日粮添加汞显著抑制比目鱼的增重、特定生长率、饲料效率和蛋白效率(P<0.05),而VE显著改善增重(P<0.05)。汞和VE对试验期间比目鱼的存活率无显著影响(P>0.05)。日粮补充VE对比目鱼粗脂肪、水分有一定影响。VE显著降低肌肉、肝脏和肾脏汞含量(P<0.05),但日粮添加汞降低了组织VE含量(P<0.05)。汞显著降低了比目鱼机体二十碳五烯酸和二十二碳六烯酸含量(P<0.05),补充VE后显著改善了机体亚麻酸和二十碳五烯酸含量(P<0.05)。结果表明,日粮中添加VE对比目鱼生长发育具有促进作用,同时有降低无机汞在机体蓄积的潜在作用。 相似文献
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《中国家禽》2015,(17)
为探讨PGC-1β基因在鸡骨骼肌中的表达情况,研究利用实时荧光定量PCR法检测了慢生型清远麻鸡和速生型隐性白羽鸡的比目鱼肌(主要含慢肌纤维)和趾长伸肌(主要含快肌纤维)PGC-1βm RNA的发育性表达变化。结果表明,清远麻鸡从0~9周龄,比目鱼肌和趾长伸肌的PGC-1βm RNA表达均呈"W"的趋势,比目鱼肌在0周龄时表达最高、5周龄时表达最低,趾长伸肌在9周龄时表达最高、7周龄时表达最低;隐性白羽鸡比目鱼肌呈"先升后降再升"的表达趋势,1周龄时出现峰值、7周龄时表达最低,趾长伸肌在3周龄时表达最高,显著高于其他各周龄(P0.05),其他各周龄间差异不显著(P0.05);相同周龄清远麻鸡比目鱼肌和趾长伸肌PGC-1βm RNA表达水平低于隐性白羽鸡。结果提示,鸡骨骼肌PGC-1βm RNA表达发育模式具有品种、年龄和表型特异性,并可能与肉品质存在关联。 相似文献
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在公路工程施工过程中的压实质量以及压实效果直接对提高路面的强度、减少塑性形变、渗透系数、饱水量及可能产生的形变并增加稳定性。本文不仅介绍了公路路基路面工程施工压实施工的关键性因素怒,研究了公路工程路基路面压实施工技术措施,并强调了公路工程路敏压实度控制的有效控制。 相似文献
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在公路工程施工过程中的压实质量以及压实效果直接对提高路面的强度、减少塑性形变、渗透系数、饱水量及可能产生的形变并增加稳定性.本文不仅介绍了公路路基路面工程施工压实施工的关键性因素怒,研究了公路工程路基路面压实施工技术措施,并强调了公路工程路敏压实度控制的有效控制. 相似文献
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探讨运动对大鼠骨骼肌细胞凋亡及钙离子含量的影响。将大鼠分为对照组、一般运动组和强运动组,对照组大鼠正常活动,一般运动组大鼠跑台速度为18m/min,强运动组大鼠跑台速度为25m/min,一般运动组和强运动组大鼠均运动至力竭。分别检测大鼠比目鱼肌和胫骨前肌细胞凋亡情况,大鼠血清和大鼠后肢组织匀浆上清中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和钙离子水平,大鼠肌肉组织中Bax、Bcl-2表达水平。结果发现,一般运动组大鼠比目鱼肌中细胞凋亡率和SOD活性均明显高于对照组,差异极显著(P0.01)。强运动组大鼠比目鱼肌中的SOD活性明显低于一般运动组,差异极显著(P0.01)。试验组大鼠血清中MDA水平均明显低于对照组,差异极显著(P0.01)。一般运动组大鼠胫骨前肌和比目鱼肌中MDA水平均明显高于对照组和强运动组,差异极显著(P0.01)。一般运动组大鼠比目鱼肌中钙离子水平和Bax表达水平明显高于对照组,差异显著(P0.05)。一般运动组大鼠比目鱼肌中Bcl-2表达水平明显低于对照组,差异极显著(P0.01)。表明一般运动比高强度运动更易导致比目鱼肌细胞凋亡,作用机制可能与钙离子浓度、氧自由基水平、Bax、Bcl-2有关。 相似文献
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文章旨在评估一种商品复合碱性矿物质对比目鱼生长性能、养分消化利用及非特异性免疫的影响。试验选择平均初始体重为(144.06±0.17)g的比目鱼900条,随机分为3组,每组5个水族箱,每个水族箱饲养60条。对照组饲喂基础日粮,处理组日粮分别在基础日粮中添加2和4mg/kg碱性矿物质,试验持续105d。结果:随着日粮碱性矿物质添加水平的升高,比目鱼的料重比表现为显著线性和二次趋势降低(P<0.05),蛋白效率和杯状细胞数量表现为显著的线性和二次曲线升高(P<0.05)。2和4mg/kg碱性矿物质组比目鱼的存活率较对照组分别提高28.95%和33.91%(P<0.05),肝脏指数分别提高21.11%和29.44%(P<0.05),肠道相对长度分别提高28.36%和27.57%(P<0.05)。2mg/kg碱性矿物质组比目鱼的干物质表观消化率分别较对照组和4mg/kg碱性矿物质组显著提高5.76%和4.68%(P<0.05),同时血清溶解酶活性较对照组和4mg/kg碱性矿物质组分别显著提高76.01%和61.39%(P<0.05)。结论:日粮添加碱性矿物质可以改善比目鱼饲料利用率和干物质消化率,对消化道组织学和非特异性免疫、抗氧化有积极影响,其中本试验条件下2mg/kg的添加水平最适宜。 相似文献
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An 11-month old entire male mouse was presented with mucopurulent discharge and corneal scarring of the left eye. This mouse previously had a history of ear mites that responded to therapy, and had undergone surgery to remove a large discharging mass from the left side of the neck. The eye problem was noted prior to surgery, but after the ear mite infection. Examination revealed absence of a palpebral reflex in the left eye, and no spontaneous movements of the left ear or lip and whiskers. Examination of the left eye revealed extensive corneal vascularisation and pigmentation. Intraocular structures were not visible. A diagnosis of facial nerve paralysis and secondary exposure keratitis was made. Surgery was performed to close the lateral canthus and reduce corneal exposure. Following surgery the eye discharge ceased and corneal vascularisation resolved, however corneal pigmentation persisted. 相似文献
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The association between ocular squamous cell tumors and various measures of solar radiation was evaluated for 2,775 contemporaneous Hereford cattle. The animals were from 34 herds located in 21 states in the United States and in one Canadian province. Examinations and photographs were made of the eyes of all cows and heifers in a herd; 33 herds were examined between June and August 1957 and 1 herd was examined in 1958. Solar radiation was measured by altitude and mean annual hours of sunshine applying to an individual herd, and global radiation, a cloudiness index, and elevation of nearby National Weather Service stations. All measures of solar radiation provided evidence of a significant association between increasing risks of developing cancer eye and increasing levels of radiation; adjustments were made for possible confounding effects of age and corneoscleral pigmentation. Associations were evident whether affliction was defined as the occurrence of any type of tumor (ie, plaque, papilloma, or carcinoma), or as the occurrence of only papilloma or carcinoma. Average ages of affected cattle also tended to be lower at high radiation levels than at low levels, further supporting the hypothesis that solar radiation has an important role in the development of this disease. In view of the heritability of eye pigmentation and its inhibitory effect on lesions, cancer eye may be controlled by selective breeding for increased pigmentation in and around the eye to afford protection against the harmful effects of incident UV radiation. 相似文献
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Bestami Yilmaz Ismail Demircioglu Deniz Korkmaz Aydın Alan Rahsan Yilmaz Abdulkadir Ciris 《Anatomia, histologia, embryologia》2021,50(2):373-378
Eyes are the most primarily required sensory organs during the migration of migratory birds and Northern Bald Ibises (Geronticus eremita) are known to make long migrations. This study examined for the first time the structure of pecten oculi in northern bald ibises by using macroscopic anatomy as well as light and electron microscopic methods. In the study 20 eye globes from 10 adult bald ibises were used. The pecten was of pleated type. As in most bird species, it was located on the optic nerve head and projects into the vitreous from the optic nerve head. The wider basal part was observed to attached to retina and its free apical part was found in camera vitrea bulbi embedded in corpus vitreum. The pecten had 13–14 accordion like pleats lying between the basal and apical parts. In addition to arterial and venous vessels, numerous capillary vessels as well as melanocytes were observed within each pleat. The bridge binding the pleats at the apical part showed a stronger pigmentation compared to other parts of the pecten. The results of the study indicated that the general morphology of pecten oculi in northern bald ibises which is a migratory bird species were similar to that in other diurnal bird species. 相似文献
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Blue discoloration of the iris was found in the left eye of a male laboratory Beagle dog, which had a normal tricolor coat and clinically showed no visual impairment. Ophthalmoscopically, the affected eye revealed red-colored tigroid fundus, in which no tapetum was present. The retinal vasculature and the optic disc showed no noticeable changes. Histopathologically, in the left eye melanocytes had extremely few melanin granules in the anterior segment, including the anterior border layer, in the stroma and sphincter muscle of the iris and in the stroma of the ciliary body and choroid. However, the posterior pigment epithelium of the iris, the pigment epithelium of the ciliary body and the retinal pigment epithelium showed normal pigmentation. The tapetal elements were completely absent. Number and distribution of the S-100 protein-positive melanocytes with or without melanin granules in the iris, ciliary body and choroid of the left eye were similar to those of the normal right eye. Ultrastructurally, melanocytes in the anterior segment of the affected iris possessed no or few melanosomes which were incompletely melanized. In the right eye, no abnormal features were observed. Based on these results, the present case was diagnosed as unilateral ocular subalbinism with tapetal aplasia in a Beagle dog. 相似文献
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M. Abdo Y. Z. Hosaka A. Erasha M. Nada S. Ali M. Uehara 《Anatomia, histologia, embryologia》2014,43(4):257-264
Studies of ocular development in the dromedary camel (Camelus dromedarius) have not been reported previously. The aim of the present investigation was therefore to document the major landmarks and the time course in the prenatal development of the eye tunics in dromedary camel and its accommodation with the surrounding hard environment of the desert. Serial histological sections of dromedary camel embryos and foetuses were used. Age estimation was made on the basis of gestational size, crown vertebral‐rump length (CVRL), which ranged 1.2–110 cm. The eye of the dromedary camel developed in a similar manner to that of the human and domestic animals eyes; the principal differences were in the time of occurrence of certain developmental events, pigmented peripheral cornea near the limbus, a remarkably thickened Descemet's membrane and pigmentation in the corneo‐scleral junction, which represent an adaptive modification in relation to a severe environment. 相似文献
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Development of the New Zealand White Rabbit Eye: I. Pre‐ and Postnatal Development of Eye Tunics 
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下载免费PDF全文 The New Zealand white (NZW) rabbit has been and is right now regularly utilized in ophthalmic surgery evaluation. Inside NZW rabbit eye, the visibility of ocular structures throughout surgical procedure is fantastic. Younger rabbits are used in different ages for the evaluation of ophthalmic surgery. Complete studies of ocular development in the NZW rabbits have not been reported previously. The aim of the present investigation was to describe the major landmarks and the time course of the pre‐ and post‐natal development of the complete eye tunics of the NZW rabbit to give a superb model as well as a fruitful area for further ophthalmological investigations. Serial histological sections of NZW rabbit prenatal (E13–E28) and post‐natal (P1–P14) stages were examined, respectively. The eye of the NZW rabbit developed in a similar manner to that of the human and domestic animals eyes; the principal differences were at the time of occurrence of certain developmental events, absence of pigmentation which represent an exploited benefit for ophthalmic surgery, remarkable Bowman's membrane at E25, poor developed ciliary stroma and juvenile retinal layer until P9. In human, the basic morphogenetic processes of the development of eye tunics are completed towards the end of the first half of gestation period. However, the latter represents the beginning stage of the development of eye tunics in the rabbit. Thus, allowing various extensive ophthalmic researches to be performed. 相似文献
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Dunkel B Sweeney RW Habecker PL Komaromy AM 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(2):181-183
This report describes a unique case of presumed migration of Parelaphastrongylus tenuis through the spinal cord into the eye of a llama where it survived and matured within the ocular environment. Blindness of the eye was most likely attributable to migration of the parasite through the central nervous tissue. 相似文献
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Barros PS Safatle AM Godoy CA Souza MS Barros LF Brooks DE 《Veterinary ophthalmology》2005,8(3):189-192
This paper describes the use of amniotic membrane in the reconstructive surgical repair of generalized keratomalacia, ankyloblepharon, and after fibrous histiocytoma removal in two dogs and a cat. Case 1 was an 11-year-old female Yorkshire terrier with severe bullous keratomalacia in the left eye (OS). A frozen canine amniotic membrane graft and a third eyelid flap were applied. At day 80 postoperatively, only a mild scar and corneal vascularization were present. Case 2 was a 4-year-old female Siamese cat with symblepharon of both eyes after rhinotracheitis. Resection of the conjunctiva and frozen canine amniotic membrane transplant were performed. One month later, there was a little corneal scarring and corneal vascularization. Case 3 was a 6-year-old female terrier with a scleral and corneal mass at the 11-12 o'clock position (OS). Resection of the mass and amniotic membrane transplantation were performed. The mass was a fibrous histiocytoma localized to the sclera and cornea. This eye healed with mild conjunctivalization and no pigmentation. Amniotic membrane transplantation can be used as a method of reconstruction of the ocular surface with good repair of the cornea and minimal scarring in small animals. 相似文献