山羊Ets-1基因cDNA的克隆与序列分析

根据GenBank已收录的牛(Bos taurus)、人(Homo sapiens)和小鼠(Mus musculus)等物种Ets-1基因序列的同源保守区域,设计特异性引物,采用RT-PCR和RACE技术,分离并克隆了西农萨能奶山羊(Capra hircus)Ets-1基因的cDNA序列。该序列全长2 263 bp(GenBank登录号HQ589338),包括5’UTR 331 bp,CDS 1 326bp和3’UTR 606 bp,编码441个氨基酸组成的蛋白质。核苷酸序列分析发现,山羊编码序列与牛、猪、人、小鼠等的相应序列同源性分别为98%、94%、92%和90%,3’UTR相应序列为96%、83%、81%和77%,5’UTR相应序列为98%、85%、82%和71%。氨基酸序列分析发现,山羊与牛、猪、人和小鼠的Ets-1的相似性较高,均在95%以上。蛋白质结构分析发现,其蛋白质分子量为50 340.8 D,等电点为5.08,具有典型的螺旋-转角-螺旋结构域,不存在跨膜结构,并且整个序列不含信号肽。     

东北民猪荷包猪抗性基因多态性及其与免疫指标的相关性研究

研究目的是检测荷包猪FUT 1和Mx1基因位点多态性及其与免疫指标的相关关系。采用PCR-RFLP技术分析基因多态性,采用ELISA方法检测免疫指标白介素-4(IL-4)、分泌型免疫球蛋白A(sIgA)、α-干扰素(IFN-α)的表达量。结果表明,荷包猪FUT 1基因和Mx1基因Hin6I点酶切位点上显示多态性,优势基因型分别为GG和AA型,在Mx1基因其他两位点处未发现多态性;荷包猪免疫指标IL-4、sIgA、IFN-α的表达量明显高于大白猪(P<0.05),但抗性基因型与免疫指标间的相关性表现不明显。     

"龙桑1号"不同部位中1-脱氧野尻霉素含量测定研究

采用高效液相色谱法测定"龙桑1号"不同部位中1-脱氧野尻霉素的含量。结果:不同部位中DNJ含量差异很大,其中桑根皮中含量最高,为0.624%;秋采桑叶中含量最低,为0.074%。     

猬迭宫绦虫裂头蚴线粒体nad1基因部分序列的多态性研

从湖南省4个不同地区的黑斑蛙大腿肌肉中采集猬迭宫绦虫裂头蚴作为研究对象,用引物Nad1u及Nad1d扩增猬迭宫绦虫裂头蚴的nad1基因片段,应用ClustalX 1.81程序对序列进行比对,同时利用DNAStar 5.0中的MeGalign程序进行同源性分析。结果显示猬迭宫绦虫裂头蚴nad1序列均为570 bp。研究结果为猬迭宫绦虫裂头蚴进一步的分类、鉴定和遗传变异研究奠定了基础。     

两种生理调节剂对南阳牛增重和饲料利用率的影响

选择400kg左右的南阳牛48头随机等数分为组，在相同基础日粮条件下，试验1组和试验2组的日粮中分别添加5mg/kg克伦特罗和2mg/kgF89，对照组不添加，经过47d的育肥试验，克伦特罗和F89组育肥牛的日增重分为0.98和0.78kg，比对照组相应提高了53.1%和218%；饲料转化效率也提高了，料重比分别比对照组降低52.9%和22.4%。克伦特罗使育肥牛的血清生长激素水平上升，T4水平下降。     

Macrocyclic lactone toxicity due to abamectin in farm dogs without the ABCB1 gene mutation

Abstract

CASE HISTORY: A 5-year-old entire female Huntaway from a sheep and beef farm was one of four dogs that developed clinical signs including hypersalivation, depression, blindness and ataxia after the death of another dog. A 4-year-old female Huntaway farm dog from a second farm was observed to be sitting down more often than usual on the day after being fed part of a calf carcass that had been treated with an abamectin pour-on.

CLINICAL FINDINGS: The first dog was ataxic and depressed but did respond to sound. The second dog presented with an acute onset of blindness, mydriasis, absence of a menace response, hypersalivation, gait abnormalities (e.g. high stepping gait and ataxia), and depression. Other presenting signs included muscle tremors, dehydration and difficulty eating. No abnormalities were detected from routine haematology and biochemistry. Analysis of samples of plasma from both dogs revealed concentrations of abamectin of 0.149 mg/L and 0.260 mg/L for the first and second dogs, respectively. Buccal swabs taken from the first dog for DNA testing for the ABCB1 gene mutation, gave a negative result.

DIAGNOSIS: In addition to the presenting signs which suggested a toxicosis, both dogs had measurable concentrations of abamectin in plasma confirming exposure.

CLINICAL RELEVANCE: Farm dogs exposed to concentrated pour-on products containing abamectin have been poisoned and recover or die. The product labels do not carry any warnings as to the risk of poisoning to dogs. This paper discusses two incidents affecting six farm dogs, but the authors are aware of more toxicoses in farm dogs exposed to abamectin.     

Baby pig diarrhea caused by coccidiosis

Summary

An outbreak of coccidiosis on two Belgian farms is described. Diarrhea started in piglets at 9 or 10 days of life. Zero to three pigs died per litter. The morbidity rate varied from 70 to 90 per cent. Histological examination of the intestines revealed shortening of villi and different stages of the life cycle of coccidia were seen in the enterocytes. Virological examination was negative for corona‐, corona‐like, and rota‐virus. A haemolytic E. coli strain was isolated in one case. As for treatment, good results were obtained by the adding of 1 kg amproleum pre‐mix per ton sow feed. Scouring pigs were treated orally with 2 cc of an amprol solution once a day. The diarrhea stopped one day after treatment.     

New alleles of chicken CD8 alpha and CD3d found in Chinese native and western breeds

Chinese native chicken breeds provide useful resources for the study of genetic diversity. In this study, the alleles of CD8 alpha and CD3d cDNA from Chinese native and introduced western breeds of chicken were analyzed at the sequence level. Six alleles were found, due to 13 amino acid replacements in the extracellular domain of the CD8 alpha sequence. There were four alleles detected in the Chinese strains, and alleles 5 and 6 were identified for the first time. Allele 6 was shared by Langshan, Beijing Fatty and Recessive White Feather chickens. Allele 2, found in the Bigbone strain, was the same as that found in the Leghorn strain H.B15.H7, and allele 3 in the Xianju breed was also the same as in the Leghorn strain H.B15.H12. Two Leghorn lines (RPL line 7 and AY519197) and the Camellia possessed an allele (alleles 1, 4 and 5), respectively, that was not found in the other lines. Nine out of 13 amino acid replacements were situated in the putative major histocompatibility complex (MHC) class I binding CDR1 (positions 30, 33 and 34), CDR2 (positions 58, 62, 63 and 65) and CDR3 (positions 90 and 106). Except for the Xianju breed, the CD8 alpha cDNA of Chinese native chicken breeds shared high homology. Two alleles were found in CD3d. Three additional nucleotides were found at positions 64, 65 and 66 in the newly discovered allele 2. This led to a difference of four amino acids (at residues 22, 23, 24 and 25) in the extracellular domain of CD3d cDNA from the Gushi, Recessive White Feather and ISA chickens compared with these of the White Leghorn and T11.15 (NM_205512). Five hybridoma clones (1C9, 1H5, 4B11, 6G5 and 13C5) against chicken CD8 alpha were generated by DNA immunization. Two monoclonal antibodies (mAbs), 6G5 and 4B11, showed reactivity to the splenocytes from five Chinese native chicken breeds, the Recessive White Feather chicken and the Leghorn (AY519197), while mAbs 1C9, 1H5 and 13C5 showed no reaction with these breeds.     

Use of β-Glucanases and β-1,4-Xylanases to Supplement Diets Containing Alfalfa and Rye for Laying Hens: Effects on Bird Performance and Egg Quality

It is well established that the use of alfalfa in diets for monogastric animals is limited by its high fiber content. However, alfalfa is a natural source of xanthophylls and gives poultry products a desirably yellow color. In addition, alfalfa saponins may contribute to reduce the levels of cholesterol in the meat and egg yolk. We have investigated the potential utilization of β-glucanases and β-1,4-xylanases for enhancing the nutritive value of alfalfa for laying hens. An experiment was conducted with 864 ISA Brown layer hens from 40 to 52 wk of age and fed on diets containing rye (19.6%) or rye and alfalfa (15.1%). The results suggested that inclusion of alfalfa in the diets reduced body weights and total egg mass (P < 0.01). Dietary supplementation with polysaccharidases was unable to significantly improve the performance of laying hens. However, egg yolks from birds that consumed diets containing alfalfa were more deeply pigmented, presenting an increase in yellowness (b*). In contrast, at the percentage of incorporation tested, inclusion of alfalfa in the diets was unable to lower the levels of cholesterol content in the egg yolk. Taken together the results suggest that exogenous plant cell wall hydrolases are not effective for improving the nutritive value of alfalfa-containing diets for laying hens, although inclusion of small percentages of the dehydrated leguminous meal may directly affect the quality of the generated poultry products.     

鸡传染性支气管炎病毒S1基因免疫对鸡的保护作用

将鸡传染性支气管炎病毒肾型 Ｔ 株 Ｓ１ 基因ｃ Ｄ Ｎ Ａ 连接于ｐｃ Ｄ Ｎ Ａ３ 的 Ｈｉｎｄ Ｉ Ｉ Ｉ与 Ｂａ ｍ Ｈ Ｉ位点之间构建含有 Ｃ Ｍ Ｖ 启动子及 Ｂ Ｇ Ｈｐｏｌｙ Ａ 信号序列的鸡传染性支气管炎病毒 Ｓ１ 蛋白真核表达质粒。实验证明, Ｓ Ｐ Ｆ 鸡肌注免疫后血清 Ｉｇ Ｇ 抗体逐渐升高,至第３５ 日龄左右达到高峰,攻毒后血清 Ｉｇ Ｇ 抗体先下降而后升高,血清 Ｉｇ Ｇ 抗体升高幅度不及 Ｉ Ｂ 油苗免疫组。质粒 Ｄ Ｎ Ａ 免疫鸡攻毒后有４０ ％ 的鸡可耐过强毒的攻击,说明 Ｓ１ 基因在体内获得了表达并使鸡产生了一定的免疫力。