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利用家蚕幼虫眠时形成新表皮以及重新合成黑色素分布于新表皮上形成固有体色斑纹等特点,用4龄入眠后的家蚕幼虫体壁组织为材料,观察离体培养体壁的色素代谢变化,探索适宜的家蚕幼虫体壁培养基及培养温度条件,眠蚕体壁的取材方法及取材时间,色素代谢观察的外观标志性状等。实验结果表明:含10%优等胎牛血清的Grace培养基适于家蚕幼虫体壁组织培养,培养温度为26℃;取4龄期入眠11~12 h后剥去旧表皮的体壁组织更容易观察色素代谢的外观性状变化;体壁培养24 h后,刚毛再生和色素沉积是易于观察的色素代谢变化标志性状。通过对家蚕4龄眠蚕离体培养体壁组织的黑色素合成抑制试验,观察到体壁外观性状变化,证明酪氨酸羟化酶催化酪氨酸转化成多巴是家蚕黑色素合成代谢途径中的一个重要环节。  相似文献   

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The normal structure and function of the piscine integument reflects the adaptation of the organism to the physical, chemical, and biological properties of the aquatic environment, and the natural history of the organism. Because of the intimate contact of fish with the environment, cutaneous disease is relatively more common in fish than in terrestrial vertebrates and is one of the primary disease conditions presented to the aquatic animal practitioner. However, cutaneous lesions are generally nonspecific and may be indicative of disease that is restricted to the integument or a manifestation of systemic disease. Regardless, a gross and microscopic examination of the integument is simple to perform, but is highly diagnostic and should always be included in the routine diagnostic effort of the aquatic animal practitioner, especially since various ancillary diagnostic procedures are either not practical or lack predictive value in fish. The purpose of this article is to provide an overview of normal cutaneous biology prior to consideration of specific cutaneous diseases in fish.  相似文献   

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In this study, we conducted a light microscopic and ultrastructural analysis of the integument of the one-humped camel (Camelus dromedarius). In general, the epidermal strata of the camel integument appeared typical of those found in non-desert mammals. Two cell populations were noted in the stratum basale: one with a flat, non-serrated base and the other with a highly serrated base. Typical fine structure was observed in keratinocytes of the stratum spinosum and stratum granulosum. The stratum corneum was six to 10 cells thick. Within the different strata, overall cell morphologies and the general distribution and relative abundance of cellular organelles appeared typical. Dermal features included the presence of myoepithelial cells surrounding apocrine tubular glands. Inter- or intracellular canaliculi within the secretory cells of the apocrine glands, reported to be present in certain other non-desert mammals, were not evident in the camel. Together, these data indicate that while the camel is clearly adapted for a desert lifestyle, these adaptations do not include significant specializations at the cellular or subcellular level in the integument.  相似文献   

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Alterations of the integument of fattening pigs were investigated on a total of eleven farms with the following housing systems: "Krieger" system, fully slatted floors, partially slatted floors and kennel housing systems. For this purpose, the alterations of the integument of the animals were visually assessed at different times during fattening. In addition, spot investigations were carried out on three farms with deep litter systems. In the non-littered systems, significantly more changes at the limbs were observed than in the littered systems. The least damages occurred in the deep litter system. Similar as with cattle, soft and deformable lying areas seem to be a prerequisite for the prevention of such alterations. With respect to injuries caused by tailbiting, apart from possibilities of activity, other parameters such as air quality and space availability also play an important role.  相似文献   

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The significant and continued transboundary spread of Asian avian influenza H5N1 since 2003, paired with documented transmission from avian species to humans and other mammals, has focused global attention on avian influenza virus detection and diagnostic strategies. While the historic and conventional laboratory methods used for isolation and identification of the virus and for detection of specific antibodies continued to be widely applied, new and emerging technologies are rapidly being adapted to support avian influenza virus surveillance and diagnosis worldwide. Molecular tools in particular are advancing toward lab-on-chip and fully integrated technologies that are capable of same day detection, pathotyping, and phylogenetic characterization of influenza A viruses obtained from clinical specimens. The future of avian influenza diagnostics, rather than moving toward a single approach, is wisely adopting a strategy that takes advantage of the range of conventional and advancing technologies to be used in "fit-for-purpose" testing.  相似文献   

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We have amplified, cloned and sequenced (part of) the open reading frame of the S1 segment encoding the sigma C protein of avian reoviruses isolated from chickens with different disease conditions in Germany and The Netherlands during 1980 up to 2000. These avian reoviruses were analysed phylogenetically and compared with sequences of avian reoviruses in the Genbank database. The avian reoviruses could be grouped in 5 different genotyping clusters and this classification was identical when the sequences were compared of the 5' end, the 3' end or the whole open reading frame of the sigma C protein. Therefore sequencing of either part of the gene encoding the sigma C protein seems to be reliable for classification. We were unable to identify a correlation between sigma C sequences of the avian reoviruses and the disease condition they were isolated from. The sequences found in The Netherlands and in Germany are, like those in Taiwan, more dispersed than the known avian reovirus sigma C sequences in the USA and Australia. We did not establish temporal or geographic differences in the avian reoviruses studied.  相似文献   

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Atherosclerotic lesions are prevalent in companion psittacine species. Parrots account for much of the veterinary scientific information on avian atherosclerosis, but the lesions have been described in virtually all avian orders. This review presents a synthesis of the epidemiologic, clinical, diagnostic, and therapeutic information known in psittaciformes, at this time, which may help in the veterinary management of atherosclerotic diseases. The article further expands on nondomestic avian species for which information is restricted to pathologic and prevalence studies. A thorough knowledge of atherosclerosis is of the upmost importance for avian clinicians as the disease is common, affects most species of birds, and seems to be associated with captive lifestyles characterized by decreased activity and nonnative diets. Therefore, avian veterinarians are expected to be largely exposed to this chronic medical condition through patient presentation and should be prepared to properly manage this disease.  相似文献   

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进行了部分禽用生物制品外源病毒检测的鸡胚检查法、细胞检查法和鸡检查法。鸡胚检查法应用SPF鸡胚检验;细胞检查法主要通过鸡红细胞吸附试验、禽白血病病毒ELISA和禽网状内皮组织增生症病毒IFA检验疫苗是否含有外源鸡红细胞吸附因子、禽白血病病毒和禽网状内皮组织增生症病毒,并提出疫苗检验的判定标准,为各兽用生物制品生产企业新城疫疫苗的外源病毒检验提供参考。  相似文献   

11.
Psittacines and other companion avian species often develop wounds requiring some form of medical or surgical therapy. Advancing technology in the field of wound care and management continues to evolve for use by the veterinary clinician. Although not all wounds can be successfully treated, many can be reduced and minimized with therapy. Consideration of the overall health, management, and nutrition of the avian patient will also aid in wound management. The avian patient with normal immune function and optimal nutrition will have improved wound healing compared with an immunocompromized or malnourished patient. The duration of treatment and potential stress of the wound-management program should also be taken into consideration when selecting a treatment program for the avian patient.  相似文献   

12.
The diagnosis of eastern equine encephalitis (EEE) virus infection in avian species is relatively difficult when compared with other species. There are no characteristic histologic lesions in the avian brain that would serve to distinguish EEE from infections with, for example, Newcastle disease or highly pathogenic avian influenza virus. Traditionally, virus isolation (VI) and/or hemagglutination inhibition (HI) has been used for a definitive diagnosis of EEE in birds. Recently, we developed an immunohistochemistry (IHC) technique for confirmatory diagnosis of EEE infection in equine brain. This test also detected EEE virus in formalin-fixed avian brain. VI confirmed IHC finding in two cases of EEE in ring-neck pheasants. IHC is a rapid, sensitive test for confirming and differentiating a histopathologic diagnosis of EEE in avian species and should be considered as an alternative test to VI or HI.  相似文献   

13.
The interest in avian medicine grows every year, and the degree of successful diagnosis and treatment in our avian patient has increased tremendously over the last 2 decades. For a veterinarian interested in avian practice there are many decisions to be made before one just accepts a patient. As outlined in this summary, there are many decisions to make regarding the level and diversity a practitioner wishes to explore (only exotics, poultry, ratites, Columbiforms, raptors, and so on) and then which equipment will be necessary to perform that level of practice. There is no master list of equipment that every avian practitioner must own. Needs must be catered to the species seen and the individual interest of the practitioner. Continuing education courses are now offered throughout the country on various aspects of avian medicine. The Association of Avian Veterinarians provides a journal, yearly conference, Web site, and a wide range of support materials. The author implores interested veterinarians to investigate these great learning experiences before casually deciding to add avian patients to a general companion animal practice.  相似文献   

14.
This paper indicates the need for, and the benefits to be gained by, better standards of avian nursing. The subject is approached by a discussion of the behaviour of birds in general and suggests ways in which stress in the hospitalized bird can be reduced to the minimum. The dangers of young birds becoming imprinted are emphasized. The contrasts between mammalian and avian anatomy, particularly of the respiratory and renal systems, are considered together with the implications when nursing birds. There is a discussion of the avian metabolic rate, the nutrition of sick birds, and some indications for physiotherapy in birds are mentioned.  相似文献   

15.
为了较全面地了解禽流感病的研究现状,本文综述了禽流感病毒的HA基因、NA基因、NF基因,通过从病人分离的禽流感病毒基因组与人流感病毒基因组比较,结果表明禽流感病毒感染人;RT-PCR方法用于建立禽流感病的分子生物学诊断技术已逐步成熟,该技术具有敏感性高、特异性强等优点;禽流感病毒重组禽痘病毒rFPV-HA-NA活载体疫苗和H5-HA质粒的核酸疫苗对预防禽流感病可能具有广阔的前景.  相似文献   

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Much of the information previously available concerning avian clinical pathology was drawn from data from domestic avian species, in particular, poultry. Clinical pathology of nondomestic avian species such as psittacines, however, has come a long way toward establishing normal reference values for caged birds. As a result, it is important for the avian clinician to learn which clinical tests can be used to detect and evaluate a single disease or disease processes by learning what information is gained from hematologic, biochemical, or cytologic samples acquired during a patient's clinical examination.  相似文献   

17.
Toll样受体家族(Toll-like receptors,TLRs)作为一种膜表面分子,是模式识别受体(pattern recognition receptors,PRRs)的主要组分,在脊椎动物和无脊椎动物中都可识别入侵的病原体相关分子模式(pathogen associated molecular patterns,PAMPs)。通过对鸡和斑胸草雀的基因组进行比对分析,发现禽中存在10种Toll样受体,其中TLR2 a、b、3、4、5和7已经证明和哺乳动物同源;有些经过基因倍增生成两个基因,TLR1La和TLR1Lb,TLR2 a和2 b;禽TLR21可能与鱼类和两栖动物的同源;禽TLR15是禽类特有的一类受体。各种禽Toll样受体在抵御各种微生物的感染过程中发挥各自重要的作用,本文就禽Toll样受体的研究进展进行简要综述。  相似文献   

18.
γ-谷氨酰环化转移酶(Y-GCT)催化γ-L-谷氨酰-L-氨基酸转换成5-氧-L-脯氨酸和L-氨基酸。当用γ-L-〔~(14)C〕-谷氨酰-α-L-氨基丁酸为该酶的底物时,观察到γ-GCT广泛分布于家蚕和蓖麻蚕的中肠、马氏管,后丝腙,脂肪体和体壁等组织中。家蚕各组织的γ-GCT在五龄中期均出现活力峰;并在白蛹期,脂肪体和体壁的γ-GCT突出地再现活力峰。这些结果表明,蚕体的γ-GCT的组织分布和活力变化,蚕体的γ-谷氨酰转肽酶和5-氧-L-脯氨酸酶存在相应关系,蚕体各主要组织细胞,将能通过这三种酶的联合作用吸收和传递氨基酸。  相似文献   

19.
1. The oxygen flux across the integument of eggs of domestic fowl, domestic duck, mallard, moorhen, pheasant and turkey shows a ten‐fold increase during the first week of incubation.

2. Suggestions are made as to how this is brought about. An assessment is also made of the contribution of the various components to the overall “resistance“ of the integument.  相似文献   


20.
Control of colibacillosis is important to the poultry industry. We have found that the presence of a gene for increased serum survival, iss, is strongly correlated with Escherichia coli isolated from birds with colibacillosis. Therefore, the iss gene and its protein product, Iss, are potential targets for detection and control of avian colibacillosis. The iss gene was amplified from a virulent avian E. coli isolate and sequenced. The sequences of the gene and the predicted protein product were compared with those of iss from a human E. coli isolate and lambda bor. The iss gene from the avian E. coli isolate has 96.8% identity with the iss gene from the human E. coli isolate and 89.4% identity with lambda bor. The Iss protein from the avian isolate has 87% identity with Iss from the human isolate and 90% identity with Bor. The low identity between the two Iss proteins is because of a frame-shift in their respective coding sequences. In sum, iss from this avian E. coli isolate is very similar to iss from a human E. coli isolate, but because of a frameshift mutation in the coding sequence of iss from the human E. coli isolate, Iss proteins from avian and human E. coli isolates have only 87% identity. The strong association of iss with E. coli isolated from birds with colibacillosis, suggests that this sequence be studied for its value as a marker or target to be used in colibacillosis control.  相似文献   

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