微孔草Actin基因核心片段的克隆及序列分析

提取微孔草Microula sikkimensis叶片的总RNA,并以其为模板,运用RT-PCR方法扩增出Actin基因的核心序列。通过连接、转化后对阳性克隆进行PCR鉴定并测序,序列分析结果表明:微孔草Actin基因核心片段长599 bp,编码199个氨基酸。将该序列与GenBank中已注册的植物Actin基因序列进行同源性比较,发现它们之间的同源性在84%以上,氨基酸序列同源性在95%以上,具有高度的保守性。     

结缕草肌动蛋白基因全长cDNA的克隆及序列分析

根据植物肌动蛋白(Actin)基因编码区的保守序列设计引物,提取结缕草叶片的总RNA,进行RT-PCR。并采用RACE技术扩增出1560bp的Actin基因全长cDNA序列。序列分析表明,该基因的开放阅读框(ORF)为1134bp,编码377个氨基酸,5′非编码区117bp,3′非编码区309bp。所得序列与GenBank中收录的其他植物肌动蛋白核苷酸序列的一致性均在85%以上,氨基酸序列的一致性高达97%以上。将其命名为ZjACT,GenBank登录号为GU290545。根据高等植物肌动蛋白相似性构建的系统进化树显示,结缕草肌动蛋白与大麦和圆锥小麦肌动蛋白之间的亲缘关系最为密切,在进化中分化时间最为接近。进一步分离克隆了结缕草Actin基因的基因组DNA序列(登录号GU290546),它由4个外显子和3个内含子组成。本研究有助于揭示植物Actin基因家族的进化历史,为研究植物Actin基因家族功能和进化上的多样性奠定理论基础,同时也为开展草坪草和牧草Actin基因的功能分析和利用研究提供参考。     

蒙古冰草肌动蛋白基因片段的克隆与组织表达分析

本研究利用同源序列法分离蒙古冰草Actin基因同源片段,并分析蒙古冰草Actin基因在根、茎、叶中的表达特征。根据禾本科植物小麦Actin基因的保守序列设计1对引物A1,经RT-PCR扩增,从蒙古冰草cDNA中克隆到1个长度为541 bp的Actin基因片段,使用DNAman和DNAUSER等分子生物学软件进行序列分析,结果表明,该序列编码179个氨基酸,并推测该片段具有Actin超基因家族的保守结构域,含有1个ATP结合位点,抑制蛋白结合位点和胶溶蛋白结合位点;该基因片段的氨基酸序列与小麦Actin基因的同源性为99%,与玉米同源性为96%,与水稻同源性为93%。组织器官特异性表达分析结果表明,该基因在根、茎、叶中的表达量恒定。将该基因片段命名为MwACT1,并在GengBank中登记注册,登录号为FJ490410。     

塔乌库姆冰草肌动蛋白基因片段的克隆及序列分析

根据其他植物Actin基因的保守序列设计一对简引并性物,以塔乌库姆冰草叶片总RNA为模板,采用RT-PCR的方法扩增出Actin基因片段并连接到载体上,阳性克隆经PCR检测后进行测序。结果表明：该片段长约600bp,编码199个氨基酸,所得序列与GenBank中注册的其他植物Actin基因序列同源性均在81%以上,与其他肌动蛋白的氨基酸序列同源性达88%。     

盐生草根系基因HgAKR6C的克隆与初步功能分析

醛酮还原酶（AKR）是构成Shaker型K+通道蛋白的保守核心结构域，在植物应对非生物胁迫时起到关键作用。本研究采用西北旱区典型盐生植物盐生草作为研究材料，基于课题组前期盐生草根系盐胁迫转录组学数据分析结果，筛选并克隆得到耐盐基因HgAKR6C。HgAKR6C基因蛋白质编码区（CDS）全长951 bp，共编码氨基酸317个。系统发育进化树分析表明，HgAKR6C与拟南芥中AtAKR6C1基因亲缘关系最近。亚细胞定位表明该基因可能主要定位于细胞质和细胞核中。qRT-PCR结果表明HgAKR6C在盐处理24 h时表达量达到峰值。构建酵母异源表达载体转化缺陷型菌株发现，HgAKR6C基因可能参与Na+的外排和介导K+的吸收。综上所述，HgAKR6C具有调节盐生草耐盐性的功能，而盐生草根系耐盐基因HgAKR6C的调控机制还需进一步的研究验证。     

无芒隐子草SAMS1基因的克隆及干旱胁迫下的表达分析

以无芒隐子草干旱诱导的cDNA文库中获得的一个与S-腺苷甲硫氨酸合成酶(SAMS)基因同源性较高的EST序列为基础,采用RT-PCR技术克隆该基因全长序列(命名为CsSAMS1),该序列全长1 399 bp,编码397个氨基酸,具有SAMS基因的典型结构特征。无芒隐子草SAMS1蛋白为亲水性蛋白,无跨膜结构域,其空间结构主要由α-螺旋和无规则卷曲结构构成。与近缘植物SAMS的氨基酸序列多重比较分析表明,不同植物的SAMS的氨基酸相似程度非常高(92%~100%), 其中无芒隐子草与水稻的相似性最高(99%), 说明SAMS基因在植物进化中非常保守。CsSAMS1基因在无芒隐子草幼苗干旱过程中的半定量和实时定量RT-PCR表达模式分析均表明,干旱胁迫诱导该基因在根中大量表达, 叶中表达量变化不明显。CsSAMS1基因受干旱胁迫的诱导表达,为进一步探讨其应用于草类作物抗旱性的遗传改良奠定了基础。     

四翅滨藜AcDREB2转录因子编码基因的克隆及其表达

脱水应答元件结合蛋白(DREB)在植物响应盐和干旱胁迫中发挥重要作用。为研究DREB在耐盐碱耐干旱的先锋植物四翅滨藜(Atriplex canescens)中的功能及其应用前景,本研究设计了一对简并引物,通过PCR扩增和RACE法克隆得到四翅滨藜DREB转录因子编码基因AcDREB2。该基因cDNA全长为867 bp,共编码242个氨基酸。序列BLAST比对与同源性分析结果表明,该基因与其他植物的DREB具有较高的同源性。利用RT-PCR方法进行表达模式分析发现,AcDREB2在四翅滨藜叶中高丰度表达,且其表达受NaCl和渗透胁迫处理的快速诱导,表明AcDREB2参与了四翅滨藜的抗逆响应。     

甘肃红豆草无色花青素还原酶LAR基因的克隆和表达分析

以甘肃红豆草为材料,采用RT-PCR法克隆无色花青素还原酶LAR基因,分析该功能基因在甘肃红豆草不同器官表达的差异性。结果表明,克隆的甘肃红豆草LAR基因,与GenBank已报道LAR基因(登录号:HM152981)序列相似性达到98.34%,其ORF长为1089 bp,编码362个氨基酸残基;其编码的氨基酸序列与不同属豆科物种的相似性存在较大的差异。基因序列已注册到GenBank,序列登录号为KP013623。LAR基因在甘肃红豆草不同器官表达差异较大;其中叶中表达量最高,其次是花和果,茎中表达量最低,这与器官间缩合单宁含量的变化规律一致。推测其表达与甘肃红豆草缩合单宁器官间的积累差异有关。这些研究结果也为探索缩合单宁积累和表达调控的机制提供基础。     

四翅滨藜AcDREB2转录因子编码基因的克隆及其表达

脱水应答元件结合蛋白(DREB)在植物响应盐和干旱胁迫中发挥重要作用.为研究DREB在耐盐碱耐干旱的先锋植物四翅滨藜(Atriplex canescens)中的功能及其应用前景,本研究设计了一对简并引物,通过PCR扩增和RACE法克隆得到四翅滨藜DREB转录因子编码基因AcDREB2.该基因cDNA全长为867 bp,共编码242个氨基酸.序列BLAST比对与同源性分析结果表明,该基因与其他植物的DREB具有较高的同源性.利用RT-PCR方法进行表达模式分析发现,AcDREB2在四翅滨藜叶中高丰度表达,且其表达受NaCl和渗透胁迫处理的快速诱导,表明AcDREB2参与了四翅滨藜的抗逆响应.     

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.     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.     

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.