集约化养猪场嗜流产衣原体病流行状况的初步调查

本试验对北京郊区5个规模化猪场断奶仔猪、育成猪、育肥猪和怀孕母猪采集血清共507份,同时采集密切接触饲养人员、仔猪、育肥猪的喉头拭子、母猪阴道拭子及公猪的精液共183份。分别使用间接血凝诊断试剂盒、法国ELISA试剂盒检测抗体;利用直接荧光染色法检测抗原,包括166份猪喉头拭子、阴道拭子和精液以及17份饲养人员喉头拭子。结果发现间接血凝诊断试剂盒、ELISA试剂盒抗体阳性率分别为4.14%和2.17%;抗原平均阳性率为14.8%,其中精液阳性率达到37.5%,母猪阴道拭子阳性率为27.5%,饲养人员阳性率为23.5%。本试验证实北京郊区猪嗜流产衣原体在种公猪、母猪群和饲养员呈高流行趋势。同时研究结果显示,5个被调查的规模化猪场嗜流产衣原体抗体阳性率显著低于有报道的其他省市,这与间接血凝诊断试剂盒检测结果高于ELISA试剂有关。针对发现的问题,必须采取有效措施控制种公猪精液污染衣原体现象,阻断向母猪和饲养人员传播,以降低人兽共患病发生的风险。     

Porcine adenoviruses. Isolation and cytopathogenic examination of four serological types

The first report of the isolation of adenovirus from a pig was that of Haig et al. in 1964. The virus was isolated from faeces and was serologically different from many of the common human adenoviruses. In Denmark, six strains have been found in organ material from pigs (Rasmussen 1966). In the USA Kasza (1966) isolated an adenovirus from the brain of a pig with encephalitic symptoms, and in West Germany the virus was demonstrated in tissue culture of pig kidney from a group of animals where up to every tenth kidney was found to be infected (Mahnet & Bibrack 1966).The present study deals with virus strains isolated from non-inoculated cell cultures or from normal or diseased pigs. It includes a serological classification of strains isolated from organ material and a study of the cytopathogenic effect of the viruses in cell cultures of the kidneys and lungs of pig embryos and of the kidneys of bacon pigs and calves.     

Analysis of the Cecum Microbial Diversity of Different Pig Breeds by Illumina Amplicon Sequencing of 16S rDNA Tag

To study the diversity and composition of the bacterial community from cecum samples from Yacha pig, Qingyu pig and Wujin pig, the investigation was designed to reveal mechanism of roughage resistance. Illumina amplicon sequencing of 16S rDNA Tag was used to analyze the cecum microbial diversity of Yacha pig, Qingyu pig and Wujin pig at 90 kg liveweight. The results indicated that the core flora of the three breeds were Bacteroidetes and Firmicutes at the phylum level and Prevotella and Bacteroides at the genus level. Meanwhile bacteria associated with cellulose decomposition were found in all three breeds, in which the number of Fibrobacter and Clostridium in Yacha pig were significantly higher than that in Qingyu pig and Wujin pig (P<0.05),and the number of Prevotella in Yacha pig was significantly higher than that in Wujin pig (P<0.05). The number of Bacteroides in Qingyu pig was significantly higher than that in Yacha pig (P<0.05).The number of Spirochaetes in Qingyu pig was significantly higher than that in Wujin pig (P<0.05). It could conclud that the composition of the cecum bacteria community was similar in above pig breeds, but there were significant differences in distribution and quantity. According to analysis of microbial related to cellulose digestibility, Yacha pig was the strongest among the three breeds, followed by the Qingyu pig and Wujin pig.     

Presence of the di-leucine motif in the cytoplasmic tail of the pig FcRn alpha chain

The sequence of the pig FcRn alpha chain was recently published. The lack of a conserved di-leucine motif in the cytoplasmic tail suggests a rare polymorphism in the described animal, alternatively, a sequencing error. We therefore cloned and sequenced the pig FcRn alpha chain. Our sequence, along with a previous NCBI GenBank submission and five pig derived EST clones clearly demonstrate the presence of di-leucine motif in the cytoplasmic tail of the pig FcRn. No polymorphism in the cytoplasmic tail-encoding region was found in 25 animals from six pig breeds based on single-stranded conformation polymorphism and sequencing analysis, suggesting that the previously described pig FcRn alpha chain may represent a sequencing error in the 3' portion of the gene.     

Genotypes and antibiotic resistance of Campylobacter coli in fattening pigs

Campylobacter coli is a food-borne zoonotic pathogen causing human gastroenteritis worldwide. The organism is a commensal in the intestine of many food production animals including fattening pigs. The role of the pig as a potential reservoir for C. coli affecting human either directly or via poultry has hardly been investigated and genetic characterization of porcine strains is needed to address this question. For this aim multilocus sequence typing (MLST) and flaB typing was applied to 256 C. coli isolates from faeces of fattening pig collected during 2009 at different slaughterhouses in Switzerland. In addition genotypic resistances towards macrolides and quinolones based on point mutations in the 23S rRNA and gyrA genes, respectively, were determined. Of the 67 sequence types (STs) obtained by MLST, 37 were found for the first time. flaB typing revealed 46 different types with 14 of them being novel and was useful to further differentiate strains with an identical ST. Quinolone resistance was detected in 33.6% and macrolide resistance was found in 10.6% of isolates. Comparison with 99 C. coli pig isolates from 2001 revealed a significant decrease in antibiotic resistance towards both groups of antibiotics and there was high overlap between genotypes of 2001 and 2009. Little overlap of porcine genotypes was found with 97 C. coli isolates from poultry collected 2008, however, macrolide resistance was significantly higher in pig isolates. In conclusion, C. coli from Swiss pig are heterogeneous containing many novel STs, findings that could reflect the partitioned Swiss pig production with almost no international breed exchange. The antibiotic resistance echoes the use of corresponding drugs in the Swiss livestock production and indicates the efficacy of restrictive application of antibiotics in order to reduce resistances.     

10个云南地方猪种微卫星遗传多样性分析

为阐明保山猪、迪庆藏猪、高贡黎山猪、丽江猪、明光小耳猪、滇南小耳猪、撒坝猪、大河猪、昭通猪、大河乌猪10个云南省优良地方猪种的群体遗传多样性和遗传结构,本试验参考ArkDB数据库中家猪14条染色体上的15对微卫星引物,对549个云南地方猪个体的耳组织样品进行了检测分析,计算各微卫星座位等位基因数（Na）、有效等位基因数（Ne）、Shannon's信息指数（I）、表观杂合度（Ho）、期望杂合度（He）、F-统计量（Fis、Fit、Fst）、基因流（Nm）、群体遗传距离等相关参数及多态信息含量（PIC）,采用NTsys 2.10软件构建聚类树,并采用STRUCTRUE 2.3.3软件评估群体遗传结构。结果显示：15个微卫星座位共检测到293个等位基因,各座位等位基因数在5~38个之间,平均等位基因数为19个,平均有效等位基因数8.3682个;10个云南地方猪群体的Shannon多样性、表观杂合度、期望杂合度和多态信息含量分别在1.4374~2.0317、0.6389~0.7756、0.7021~0.8281和0.6647~0.7993之间。各座位单个群体内近交系数（Fis）、总群体近交系数（Fit）、群体间遗传分化系数（Fst）的变化范围分别为-0.0678~0.4594、0.0618~0.5567和0.0713~0.1801;群体间Fst平均值为0.1101,处于中度遗传分化状态,有11.01%的遗传变异来自于群体间,大部分遗传变异来自于群体内;每个座位基因流程度较高,变化范围在1.6392~3.2551之间,平均值为2.0214。基于Nei氏遗传距离构建UPGMA系统发生树显示,高黎贡山猪与迪庆藏猪聚为一支,并与丽江猪、保山猪和明光小耳猪聚为一大支,其结果得到了STRUCTURE分析的验证。综上所述,10个云南地方猪种遗传多样性丰富,群体内有近交现象,群体间处于中度遗传分化,存在着一定的基因交流。     

Soil contamination of Toxoplasma gondii oocysts in pig farms in central China

Toxoplasmosis in pigs is a large threat to pig industry as well as pork consumers. Most pigs become infected by ingestion of oocysts from contaminated environment (soil, water and feed) or infected animal tissues postnatally. In the present study, field studies were conducted to evaluate the relationship between soil contamination status of Toxoplasma gondii oocysts and T. gondii infection in pigs in 12 pig farms with different density of cats in central China. The presence of T. gondii oocysts in soil were determined by PCR and loop-mediated isothermal amplification (LAMP). T. gondii DNA was found in 11 farms with different cat density excepting one farm exposed to low cat density. Twenty (21.1%) and 36 (37.9%) of 95 soil samples were T. gondii positive by PCR and LAMP, respectively (0.01相似文献   

湖南省衡阳市生猪生产现状分析

从湖南省衡阳市生猪生产的现状入手,详细分析了衡阳市近10年来生猪存栏、肉猪出栏、猪肉产量及生猪价格情况,发现衡阳市的生猪生产整体水平较高,运行良好;其生猪价格呈周期性波动,大约每3~4年为1个波动周期。建议:一是继续巩固衡阳市生猪生产地位,平稳发展;二是建立完善的兽医服务体系;三是完善产品市场体系、加快产业化发展。     

Methicillin resistant Staphylococcus aureus colonization in pigs and pig farmers

Methicillin resistant Staphylococcus aureus (MRSA) colonization has recently been identified in pigs and people that work with pigs, raising concerns about the role of pigs as reservoirs of MRSA for human infection. The objectives of this study were to evaluate the prevalence of MRSA colonization in pigs and pig farmers in Ontario, Canada and to characterize MRSA strains. Nasal and rectal swabs were collected from 285 pigs from three different age groups from 20 pig farms. Nasal swabs were collected from farm personnel and a brief questionnaire was also administered. The prevalence of MRSA colonization in farms was 45% (9/20) whereas the prevalence in pigs was 24.9% (71/285). There was no difference in MRSA colonization between age groups. The prevalence of MRSA colonization in pig farmers was 20% (5/25). There was a correlation between the presence of MRSA in pigs and humans on farms (P value=0.001). The results of spa typing revealed the predominant strain in pigs and humans was eGenomics spa type 539 (Ridom t034, clonal complex 398) which accounted for 59.2% of isolates and has been reported in pigs in Europe. A common human epidemic clone, CMRSA-2 (USA100, clonal complex 5) was also found in both pigs and pig personnel. Indistinguishable strains were found in pigs and pig personnel on all five farms with a colonized human. This study demonstrates that MRSA is common in pigs in Ontario, Canada, and provides further support to concerns about transmission of MRSA between pigs and humans.     

No serological evidence for the presence of swine vesicular disease virus in South Africa.

An indirect ELISA incorporating a protein A-peroxidase conjugate was developed for detecting antibodies to swine vesicular disease virus (SVDV) in pig sera. This test and a conventional virus neutralization test were found to be equally sensitive. A total of 2846 pig sera collected from various abattoirs in South Africa were tested using the indirect ELISA. No serological evidence of infection with SVDV in pigs in South Africa was found.     

Five-year trends in female pig mortality on commercial breeding farms in Japan

High mortality in female pigs on breeding farms is a critical problem in the U.S. swine industry. The objectives of this study were to determine whether female pig mortality on Japanese commercial farms increased; to investigate correlations between the mortality and herd-management factors, especially herd size and lactation length; and to determine herd repeatability in female pig mortality. A five-year annual measurement data between 1999 and 2003 were abstracted from recording files of 113 farms in Japan. The year-effects on measurements were analyzed by using repeated measures data between 1999 and 2003 in mixed-effects linear models. The annual mortalities for female pigs in 1999, 2000, 2001, 2002 and 2003 were 4.93%, 5.25%, 5.40%, 5.32%, and 4.85%, respectively. The year-effect on the female pig mortality was not found for the five years. Neither herd size, lactation length nor other management factors were found to be consistently correlated with female pig mortality for the five years. The repeatability of the mortality was 36.5% on commercial farms. In conclusion, female pig mortality did not increase during these five years in Japan. Herd size and lactation length were not risk factors for female pig mortality.     

梅山猪和香猪Prop-1基因的初步比较

Prop-1基因编码一种影响垂体前叶发生的转录因子,在人和动物均已发现由于该基因突变而引起的综合性垂体功能障碍,进而影响生长和繁殖。梅山猪和香猪的繁殖力和生长性能差异非常显著,为了了解这些差异的遗传基础,对两种猪的Prop-1基因进行了测序和比较。梅山猪Prop-1基因第198密码子为TTG,编码亮氨酸,而香猪为GTG,编码缬氨酸,即两种猪的Prop-1基因产物不同;在Prop-1基因终止密码下游250bp左右有一个腺苷酸丰富区,梅山猪有14个腺苷酸串联,香猪有11个腺苷酸串联。上述结果为进一步研究梅山猪和香猪之间生产性能差异的遗传基础提供了新线索。     

Some characteristics of a laboratory produced strain of Oesophagostomum dentatum

The isolation of Oesophagostomum dentatum from pig is described, and several morphological characteristics of the parasite and some special features about its life-cycle are illustrated and discussed.Ninety-eight female worms with a tail-length of about 350 μm were isolated from one sow. The eggs were separated from the uterus and transferred to a culture medium. The infective larvae obtained were fed to a Vietnamese miniature pig. As a control for the species isolation, a Belgian landrace pig was infected with 2000 L₃, which had originated from the Vietnamese pig. Eight weeks later the control animal was slaughtered; the tail-length of 200 female worms isolated was measured. The measurements showed a symmetric and normal distribution with a mean of 313.23 μm.Five three-month-old sows were each infected orally with 50 000 O. dentatum larvae. The prepatent period was found to be between 26 and 28 days. The egg-counts fluctuated widely and after killing the pigs only a small number of mature worms were found to be present. Histological examination of the mucosa of the intestines did not show a prolonged histotropic phase. Two hundred worms from each pig were measured, and the lengths were 8.72 to 10.83 mm for females, 7.70 to 8.74 mm for males. The length of the spicules ranged from 1004 to 1043 μm, and the tail-length of the females from 299 to 18.75 μm. Only the measurements of the tail-length belonged to a symmetric population. The adult worms had a buccal capsule with parallel sides and a club-shaped oesophagus.     

Characterization of pig T cell growth factor and its species-restricted activity on human, mouse and sheep cells

Crude T cell growth factor was prepared from pig blood cells in mixed lymphocyte culture together with Concanavalin A. The TCGF was recovered from the crude supernatant by ammonium sulphate precipitation and fractionated by gel exclusion chromatography to yield active fractions corresponding to an apparent molecular weight of 23,000d. The TCGF was further purified by isoelectric focussing and was found to migrate as a single peak of pI 5 - 5.5. The crude preparation was found to support the growth of mouse and sheep activated cells but had no effect on human activated cells. Human TCGF supported the continued growth of activated pig cells whereas mouse and sheep TCGF had no such effect.     

Monoclonal antibodies specific for pig serum and cell surface IgM

Two monoclonal antibodies were prepared which react specifically with pig serum immunoglobulin and with the population of B lymphocyte-bearing surface immunoglobulin. Comparison of our monoclonal antibodies with reagents specific for gamma, mu and alpha immunoglobulin chains in double immunodiffusion and immunoelectrophoresis revealed that the monoclonal antibodies recognise IgM in pig serum and mu chain or mu chain-like molecules on B lymphocytes. The monoclonal antibodies, designated LIG 2 and LIG 4, reacted positively with adult pig sera but not with fetal or precolostral sera or with sera from other animal species. LIG 2 and LIG 4 reacted with 15 per cent of cells from the peripheral blood lymphocyte population, 20.2 per cent of spleen cells and 20 per cent of lymph node cells, but did not react with pig erythrocytes, granulocytes or cells isolated from thymus, or with the lymphocytes of other species. Positive reactions were also found on lymphatic and intestinal tissue sections. No genetic polymorphism was found in the pig population revealed by the monoclonal antibodies. The monoclonal antibodies LIG 2 and LIG 4 may be useful for studying the pig immune system, especially as a standard reagent for measuring pig serum IgM and for the identification of positive B lymphocytes.     

不同猪种肉质相关基因Hal、RN和FTO的多态性研究

为了明确肉质相关基因氟烷基因(Hal)、酸肉基因(RN)和脂肪肥胖相关基因(FTO)在国内外不同猪种群体间的遗传变异特性,本研究以大约克、长白、杜洛克和金华猪等猪种群体为研究对象,应用PCR-RFLP技术分别检测了Hal、RN和FTO基因的多态性,并分析了FTO基因上2个多态位点g.276G＞T和c.594C＞G的遗传变异情况.结果表明:(1)在杜洛克猪中发现了Hal的基因型HalN Haln,其频率为0.166,但未发现基因型Haln Haln,其它猪种群体中仅检测到了基因型HalN HalN;(2)在已检测的所有猪种群体中只检测到RN基因的rn/rn基因型,未发现rn/RN和RN/RN基因型;(3)在FTO的g.276G＞T位点上,金华猪呈现单态,其它猪种群体均呈现多态.在FTO的c.594C＞G位点上,4个猪种群体均呈现多态,3个外来猪种群体均以CC基因型频率较高,而金华猪则以GG基因型频率较高.研究结果提示,由于Hal基因在养猪生产中的利弊双重性,因此在某些猪种群体中仍然存在较高频率的HalN Haln基因型.此外,结合FTO基因的生理功能和已有的研究结果,可在特定的猪群中将其作为影响猪肉质性状的候选基因.本研究发现FTO的基因型分布在我国优良地方猪种金华猪与国外3个种猪群间存在较大差异,为深入研究不同品种猪的肉质形成机理提供了基础数据.     

贵州地方猪品种对氧磷脂酶1基因的多态性研究

本试验以欧洲猪种为参照,研究贵州地方猪对氧磷脂酶1(paraoxonase,PON1)基因的多态性,探讨基因多态性与地方猪的脂肪沉积之间是否存在相关性。研究采用锚定聚合酶链反应技术对香猪、糯谷猪、萝卜猪和可乐猪共138个贵州地方猪品种PON1基因的单核苷酸多态性(single nucleotide polymorphisms,SNP)进行研究。结果表明,猪群PON1基因的163/165位点出现A/T、G/A变异,515位点检测到C/T突变,均以3种基因型存在。经卡方(χ²)检验,贵州地方猪群PON1基因515位点的基因型频率和基因频率与欧洲猪品种间的差异不显著(P>0.05);163/165位点中,贵州地方猪种A等位基因的频率为83.7%,明显高于欧洲猪品种(25.2%)。贵州地方猪品种PON1基因的163/165位点A等位基因占优势,编码的第55位氨基酸为甲硫氨酸(Met55),与脂代谢异常人群的基因型相同;欧洲猪种以B等位基因为主(P<0.01),编码的第55位是亮氨酸(Leu55),与正常人群的基因型一致。以人PON1蛋白的晶体结构为模板,推导出香猪PON1蛋白的三维结构。地方猪PON1基因变异导致的Met55突变可能影响PON1水解酶活性中心的疏水环境,可能使蛋白的水解酶活性下降,使得地方猪品种的脂肪沉积量和肉质不同于欧洲猪种。由此推测,贵州地方猪品种PON1基因163/165位点存在多态性,可能与地方猪种的脂肪沉积和肉质有一定的相关性。     

三江白猪相对于亲本特异性条带的筛选

本试验是出于三江白猪的保种计划所做的研究。利用RAPD技术,在前期研究的基础上,利用已筛选出的15条10bp的随机引物,在已经优化的RAPD反应条件基础上,对三江白猪及其亲本长白猪与东北民猪组织DNA进行PCR分析。从中筛选出三江白猪相对于亲本的特异性条带,找出三江白猪相对于亲本的基因组变异情况,为三江白猪种间特异性条带的确定奠定基础。     

豚鼠染色体核型及带型的研究

用骨髓细胞染色体制备法研究了豚鼠染色体核型及带型。结果表明：豚鼠染色体核型为2n=64,雄豚鼠为XY,雌豚鼠为XX;在常染色体中,亚中着丝粒或近端着丝粒的染色体有14对、端着丝粒的有17对;X染色体为中着丝粒,Y染色体为端着丝粒。所有染色体均能出现明显的C带带型,其中常染色体和X染色体的着丝粒部位被深染,两个臂均为浅染;Y染色体几乎全部深染,极易识别。染色体标本经G显带技术处理后,豚鼠常染色体和性染色体的着丝粒区均浅染,两臂上显示出清晰的G-带带型。Ag-NOR s位于1、19、20号染色体上,Ag-NOR s的众数为3个,分布范围1~6之间,Ag-NOR s具有多态性,在不同的染色体上银染的颗粒大小、深浅度不同。