核酸疫苗在防治寄生虫病中的应用

所谓核酸疫苗，就是把外源基因克隆到真核质粒表达载体上，然后将重组的质粒DNA直接注射到动物体内，使外源基因在活体内表达，产生的抗原激活机体的免疫系统，引发免疫反应。核酸疫苗是继灭活疫苗，减毒活疫苗和基因工程重组蛋白疫苗之后的第3代疫苗。1994年5月世界卫生组织全球疫苗和免疫规化等三个机构在日内瓦联合召开核酸疫苗会议，与会者充分肯定了核酸疫苗的潜在应用价值。     

DNA疫苗及其在动物传染病中的应用

DNA疫苗(DNA vaccine)又称基因疫苗 (gene immunication),核酸疫苗(nuclenic acid immunication),是一种将某种保护性抗原的编码基因克隆到真核细胞表达调控序列的质粒中,并制成DNA的重组质粒,直接给动物注射后,质粒     

寄生虫核酸疫苗的研究概况

核酸疫苗是一种将某种保护性抗原的编码基因克隆到真核细胞表达调控序列的质粒中 ,制成 DNA的重组质粒 ,直接给动物注射后质粒 DNA在组织内扩散 ,被宿主细胞摄取 ,随后通过宿主细胞的转录翻译系统 ,表达保护性抗原蛋白 ,在抗原蛋白释放分泌的同时 ,诱导机体发生免疫应答 ,产生对该抗原的保护性免疫 ,以达到治疗和预防疾病的目的。因此核酸疫苗又称基因疫苗 [1]。其包括 DNA疫苗和 RNA疫苗 ,目前研究最多的是 DNA疫苗 ,由于其不需要任何化学载体 ,又称 DNA疫苗。本文就寄生虫核酸疫苗的研究作一综述。1　核酸疫苗的研究概况1 994年 5…     

核酸疫苗的免疫效果与安全性

核酸疫苗是通过基因重组手段将编码某种抗原蛋白质的基因与载体重组后直接导入动物体内,在宿主体内表达抗原从而引起机体免疫应答的新型疫苗,是一种与传统疫苗截然不同的新型疫苗,被誉为第三代疫苗。核酸疫苗可诱导细胞免疫并可抵抗母源抗体干扰,它的诞生给基因治疗和免疫学领域带来了不可估量的前景。核酸疫苗目的基因、质粒载体的选择,接种剂量以及应用的佐剂等因素直接影响到核酸疫苗的免疫效果。DNA疫苗自诞生以来,其安全性一直是人们关心的问题,也是DNA疫苗得以日后应用于临床的关键。     

核酸免疫与核酸疫苗研究进展

核酸免疫是利用重组DNA技术将保护性抗原蛋白基因克隆到真核表达载体,并将其直接导入体内,使抗原蛋白经过内源性表达递呈给免疫系统,诱发机体产生特异性的体液免疫和细胞免疫反应。核酸免疫也称DNA免疫或基因免疫。用于免疫注射的质粒DNA称为核酸疫苗(nucleicacidvaccine)或DNA疫苗(DNAvaccine)。核酸疫苗不同于传统的弱毒苗、灭活疫苗及蛋白亚单位苗,它是带有特异抗原基因的真核表达质粒。1　核酸免疫的发展核酸免疫是随着现代分子生物学和免疫学的发展而产生的。70年代末,Israel等将纯化的多瘤病毒DNA直接注射小鼠,证实裸DNA可被…     

核酸疫苗在防治寄生虫病中的应用

所谓核酸疫苗,就是把外源基因克隆到真核质粒表达载体上,然后将重组的质粒DNA直接注射到动物体内,使外源基因在活体内表达,产生的抗原激活机体的免疫系统,引发免疫反应.核酸疫苗是继灭活疫苗、减毒活疫苗和基因工程重组蛋白疫苗之后的第3代疫苗.1994年5月世界卫生组织全球疫苗和免疫规化等三个机构在日内瓦联合召开核酸疫苗会议,与会者充分肯定了核酸疫苗的潜在应用价值.     

DNA疫苗在动物医学上的研究进展

DNA疫苗,又称核酸疫苗或基因疫苗,是指将编码引起保护性免疫应答的目的基因片段插入质粒载体,然后将重组质粒直接导入机体,通过宿主细胞的转录系统表达目的抗原,进而诱生保护性免疫应答的一种生物制剂。目前在动物医学领域,DNA疫苗已经在许多动物身上进行了研究,并取得了一定的     

核酸疫苗的研究与应用

核酸疫苗(nucleicacidvaccine)是指将含有编码某种抗原蛋白的外源基因(DNA或RNA)序列质粒载体作为疫苗,直接导入到动物细胞内,通过宿主细胞的表达系统合成抗原蛋白,诱导宿主产生对该抗原蛋白的免疫应答,以达到预防和治疗疾病的目的。核酸疫苗又称为基因疫苗或裸DNA疫苗,核酸疫苗包括DNA疫苗和RNA疫苗。这种免疫称为核酸免疫、基因免疫、DNA介导的免疫以及遗传免疫等。核酸疫苗与传统疫苗相比有许多优势。1核酸疫苗的研究历史核酸疫苗是由基因治疗发展而来的,1990年Wolff等发现,在小鼠肌肉组织内直接注射质粒DNA后,质粒及其携带的外…     

核酸疫苗的应用现状和发展前景

核酸疫苗是将编码某种抗原蛋白的外源基因（DNA）与质粒重组后直接导入动物细胞内，并通过宿主细胞的转录系统合成抗原蛋白，诱导宿主产生对该抗原蛋白的免疫应答，以达到预防和治疗疾病的目的。因此，核酸疫苗也称基因疫苗。它包括DNA疫苗和RNA疫苗，其中DNA疫苗由于不需任何化学载体，故又称裸DNA疫苗。同单链RNA相比，双链DNA具结构稳定、操作简单等许多优点，所以DNA疫苗比RNA疫苗更受学者们的青睐。１核酸疫苗在疾病防治方面的应用自１９９０年，Wolff发现DNA能直接诱导机体产生免疫应答以来，通过国内外学者的不断努力，…     

第三代新型疫苗--核酸疫苗的研究概况

核酸疫苗(nucle ic acid vaccine)也称基因疫苗(genetic vaccine)或DNA疫苗(DNAbased immunization),是指将含有编码某种抗原蛋白的外源基因与质粒重组后直接导入动物细胞内,并通过宿主细胞的转录系统合成抗原蛋白,诱导宿主产生对该抗原蛋白的免疫应答,以达到预防和治疗疾病的目的。核酸疫苗包括DNA疫苗和RNA疫苗。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

A brief history of the prevention of infectious diseases by immunisations

Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.     

Micronutrient Content of Certain Tropical Conventional and Unconventional Feed Resources of Southern India

The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies.     

Bovine Mastitis in Selected Areas of Southern Ethiopia

A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian, were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.2%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples, Staphylococcus accounted for 39.2%, Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area.     

不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响

本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P0.05),干物质采食量(DMI)显著降低(P0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。     

Microsporidial keratopathy in two dogs

A microsporidial keratopathy is described in two dogs. Both dogs presented with a unilateral stromal keratopathy characterized by multifocal coalescing opacities, and the diagnosis was made on histopathologic examination of keratectomy specimens. Transmission electron microscopy (TEM) on formalin‐fixed, paraffin‐embedded corneal tissue was performed in one dog, and the morphologic features were consistent with Nosema species infection. Both dogs were initially diagnosed and treated by superficial keratectomy. One dog received additional antifungal medication and underwent a penetrating keratoplasty following local recurrence two years later. No other systemic lesions attributable to the microsporidial infection were identified clinically. The clinical and diagnostic pathology findings, treatment, and follow‐up are discussed.     

优质肉鸡S3系体重与体尺性状指标的主成分分析

为研究地方优质肉鸡S3系体重和体尺性状之间的内在相关性,12周龄时选取同一饲养条件下的150只鸡(公母各半)进行体重和体尺性状等7个指标的测定。结果表明:S3系公鸡的体重、体斜长、龙骨长、胸角均显著高于母鸡(P0.05);公母鸡体重、体斜长、胸宽、胫围这4项指标变异系数较大,有较大选育空间;体重与体斜长、龙骨长、胸宽、胸角、胫围呈极显著正相关(P0.01),相关系数分别为0.57、0.52、0.51、0.49和0.47,与胸深、胫长呈显著相关(P0.05),相关系数分别为0.44和0.39;其他各体尺指标间也存在不同程度的正负相关性(P0.05或P0.01);体重和7个体尺性能指标综合成5个复合指标,累计贡献率达92.6355%,其中第l、2、3、4、5主成分分别解释总变异的36.5353%、22.8642%、13.3115%、10.4535%和8.4710%;各主成分的特征根分布较广,经统计计算入选的5个主成分所包含信息的侧重点各有相同,分别都在一定程度上反映了S3鸡的体型特征和生长发育规律,为今后选育出更加符合市场需求的屠宰加工优质型肉鸡指明了的方向。     

Efficacy of tropicamide,homatropine, cyclopentolate,atropine and hyoscine as mydriatics in Angora goats

Abstract

AIM: To document the efficacy of five commercially available mydriatics for their potential for diagnostic and therapeutic use in Angora goats.

METHODS: Over 8 weeks, the mydriatic effects of 1% tropicamide, 2% homatropine, 1% cyclopentolate, 1% atropine and 0.25% hyoscine were evaluated. Given as block treatments, drugs were applied randomly to one eye of 10 Angora goats, and the contralateral eye served as a control. Vertical and horizontal pupil diameters were measured to document onset ofeffect, time to reach a difference of 5 mm in the vertical/horizontal pupil diameter between eyes, time to maximum pupillary dilation, and duration of mydriatic action.

RESULTS: Onset of mydriasis for all drugs occurred within 15 minutes. Time to reach a difference of 5 mm in the vertical pupil diameter between eyes was shortest for 1% tropicamide and 0.25% hyoscine (0.5 h), then 2% homatropine and 1% atropine (0.75 h), and longest for 1% cyclopentolate (1.5 h). The maximum vertical pupillary dilation occurred earliest with 1% tropicamide and 1% atropine (2 h), followed by 0.25% hyoscine (3 h), 2% homatropine (4 h), and latest with 1% cyclopentolate (8 h). The duration of vertical dilation of the pupil was shortest with 1% tropicamide (6 h), then 2% homatropine (12 h), 1% cyclopentolate (12 h), 1% atropine (24 h), and longest for 0.25% hyoscine (96 h).

The time to reach maximum horizontal dilation of the pupil in treated eyes was shortest with 1% cyclopentolate (1 h), followed by 1% tropicamide (1.5 h), 0.25% hyoscine (3 h), 2% homatropine (3.5 h), and 1% atropine (4 h). The duration of horizontal pupil dilation was shortest with 1% tropicamide (4.5 h), and longest with 0.25% hyoscine (48 h).

CONCLUSION: All five mydriatics induced clinical dilation. Tropicamide (1%) had the shortest duration of effect, but gave incomplete dilation. Good dilation was achieved with 1% cyclopentolate and 2% homatropine, but took too long to reach maximum dilation for routine mydriasis. The largest vertical dilation of the pupil was achieved with 1% atropine and 0.25% hyoscine, but pupils remained dilated for more than 24 h.

CLINICAL RELEVANCE: For routine mydriasis in goats, it is recommended that 1% tropicamide be used, though there may be incomplete dilation. For a longer duration of mydriasis, such as in the treatment of anterior uveitis, 1% atropine or 0.25% hyoscine would be the drugs of choice.