Variation in the immune status of two Australian pig breeds

Objective To investigate the variation in immune competence of two Australian pig breeds.
Design A panel of immune tests were used to assess breed and sire differences in weaner piglets of Large White and Duroc breeds.
Procedure All piglets were immunised against porcine leptospirosis. Blood samples were taken for studies on lymphocyte phenotypes, mitogenic responses of blood cells and serological analysis.
Results Significantly larger blood leucocyte numbers were found in Large White piglets compared with Duroc piglets after vaccinations. No significant difference in concanavalin A induced blood cell proliferation was found between these two breeds before or after vaccinations. Some significant breed variation in blood lymphocyte phenotypes was found. While the age-related changes of lymphocyte phenotypes were similar for the two breeds, the Large White breed had significantly larger numbers of CD2+ and CD4+ cells than the Duroc breed after the two vaccinations. There were also significant sire effects on CD8+ cells within the Large White breed after the first vaccination. No significant breed difference was detectable in serum IgG concentrations but sire differences within each breed before the primary vaccination were found. The serum antibody response to vaccination against leptospirosis was generally small, and showed no variations due to either breed or sire. No gender effects were found during the entire study.
Conclusion The study demonstrated significant differences in some important immune components of the pig breeds studied. This may in turn indicate the variation in their immune competence or disease resistance. However, further investigation into the heritability and correlation with specific immune responses is required.     

藏猪生长激素(GH)基因HaeⅡ多态性分析

用PCR-RFLP方法检测了94个藏猪个体的生长激素(GH)基因的HaeⅡ多态性。结果发现了5个HaeⅡ酶切位点,3种等位基因(A、B、C),3种基因型(AA、BB、BC)。A、B、C3种等位基因的频率分别为14.5%、74.5%、11.0%,经T检验,发现3种基因频率之间差异达到极显著水平(P<0.01)。     

PrP genotyping of Austrian sheep breeds

Scrapie, an ovine and caprine transmissible spongiforme encephalopathy, is widely spread among sheep populations in many European countries. As it is known that susceptibility to scrapie is determined genetically, breeding programmes aiming at providing scrapie-resistant flocks have been established. Selection is based on the prion protein (PrP) genotype, which is used to classify animals into risk groups of susceptibility (R1-R5) according to the amino acids encoded by codons at positions 136, 154 and 171, respectively. At position 136 (136V-->136A) alanine and at position 154 (154H-->154R) as well as 171 (171Q-->171R) arginine are the favoured amino acids. Whereas PrP genotyping data are available for many of the European sheep breeds, comparable data for local Austrian sheep breeds are missing. The most known among these are Tyrolean mountain sheep, forest sheep. Tyrolean stone sheep and Carynthian sheep. The genotypes of 112 sheep from these four local breeds were determined. In terms of PrP genetics, Austrian breeds belong to the group of non-valine-breeds, with the exception of the Carynthian sheep, that exhibited a frequency of 136V of 4.2%. The most frequent allele was ARQ with 64.6-71.2% (depending on the breed), followed by ARR (14.8-25.8%). In contrast to the above-mentioned findings, scrapie has never been diagnosed in any of the Austrian sheep breeds. Native Austrian sheep breeds exhibit a very robust constitution, a pronounced adaptation to harsh climates and good reproduction parameters as well as a marked mother instinct. Therefore, these breeds are often used in crossbreeding programmes. Beside the above-mentioned characteristics, our results indicate that the investigated breeds may be effectively used in crossing-out breeding programmes for eliminating valine at position 136 of PrP.     

Association of polymorphism in the alpha (1,2) fucosyltransferase gene with growth performance in two Western pig breeds in Taiwan

The mutation at 307 bp (M307) of the alpha (1,2) fucosyltransferase gene has been proposed as being a marker for selection of E. coli F18 adhesion-resistant pigs. Nonetheless, exactly how this mutation affects pigs' growth performance remains unclear. This study investigated genotypic frequencies and the effect of M307 and the ryanodine receptor (RYR1) on the growth performance of two major Western pig breeds in Taiwan. In total, 1510 (1024 Duroc and 486 Landrace) boars were performance tested using segregated early weaning entrance. The genotypes of M307 and RYR1 were determined by polymerase chain reaction-based restriction fragment length polymorphism. The performance traits included average daily gain, the feed conversion ratio, backfat thickness, and age at 110 kg of body weight. The statistical model included starting age, test season, genotype of M307, genotype of RYR1, and two- and three-way interactions. The data were analyzed within breeds. Consequently, the genotypic frequencies of the AA genotype in M307 were 0.06 and 0.06, and of the GG genotype were 0.53 and 0.64 in Duroc and Landrace pigs, respectively. The genotypic frequencies of the NN genotype in RYR1 were 0.75 and 0.99, and of the nn genotype were 0.01 and 0.00 in Duroc and Landrace pigs, respectively. There was no significant effect of the M307 genotype on the growth performance in either Duroc or Landrace breeds. However, the RYR1 significantly influenced the average daily gain and age at 110 kg of body weight of Duroc pigs. The results suggest that selection of the favorable AA genotype at M307 for E. coli F18 adhesion resistance may not affect the growth performance traits in Duroc and Landrace pigs. However, the effect of the RYR1 on growth performance should be monitored during selection.     

国外猪种大量引进导致本土猪种濒临灭绝的原因分析及应对建议(以玉山黑猪为例)

玉山黑猪,距今已有两千多年的饲养历史,像国内其他地方猪种一样,都是老祖宗留给后人的宝贵财富.20世纪80年代以前,农村家庭养猪以饲养地方猪种为主,以玉山黑猪为例,1981年调查时有生产公猪52头,生产母猪9700头,但自从20世纪80年代后期我国大量引进外国瘦肉型猪后,为追求高产肉量和短期经济效益,养猪户纷纷转向养殖外...     

贵州地方猪品种与欧洲猪品种MUC13基因的多态性比较

产肠毒素大肠杆菌(Enterotoxigenic Escherichia coli,ETEC)是导致仔猪腹泻的主要病原,MUC13基因被认为是控制仔猪ETEC易感或抗性的候选基因。本文通过等位基因特异性PCR(Allele-specific PCR)方法对4个贵州地方猪种MUC13基因的多态性进行研究,并与两个欧洲猪群相比较。结果显示:贵州地方猪群中MUC13基因的G等位基因频率较高,特别是香猪和黔北黑猪群体分别达到了95.21%和96.43%,与贵州地方猪品种优良的抗腹泻表现相符。提示贵州地方猪品种MUC13基因的G119A位点可以作为抗腹泻筛选的SNP分子标记。     

7个猪品种IBSP基因结构变异SV13的群体分析

应用Hiseq 2000平台测定了香猪的全基因组序列,从中发现整合素结合涎蛋白(IBSP)基因内含子4中存在结构变异,命名为SV13,为了进一步探究SV13在猪群体中的分布,采用PCR技术检测了7个猪品种的SV13基因型。7个猪品种群体中均存在DD、DA和AA三种基因型,对纯合的DD和AA基因型测序,明确D等位基因缺失了227 bp。香猪、可乐猪和糯谷猪群体以DD为优势基因型,大白猪以AA基因型为主,6个地方猪品种群体中D的基因频率明显高于大白猪品种(P0.01),香猪和大白猪群体基因型频率处于Hardy-Weinberg不平衡状态(P0.05)。SV13可以作为辅助鉴别6个地方猪品种和大白猪的分子标记。     

基于测序技术的海南地方猪TLR2基因多态性分析

为了解海南地方猪TLR2基因的多态性,本研究采用PCR法从五指山猪、临高猪和屯昌猪3种海南地方猪的血液中克隆Toll样受体2(TLR2)基因,并进行测序及序列分析。结果显示,3种海南地方猪TLR2基因的扩增长度均为2649bp,编码区长2358bp。3种猪TLR2基因序列的种内比对结果显示,五指山猪种内有7个核苷酸位点存在多态性,2处位于编码区;屯昌猪种内有5个核苷酸位点存在多态性,均在编码区外;临高猪种内有4个核苷酸位点存在多态性,1处位于编码区。种间比对结果显示3种猪有12个核苷酸位点存在多态性,其中3处为错义突变,导致氨基酸改变。同源性分析结果显示,3种猪的TLR2基因序列高度保守,同源性在99.6%~99.9%之间。蛋白质结构预测分析显示,海南猪TLR2基因在876、1454位点呈现的AG突变均引起了其蛋白质二级结构和三级结构的改变,提示可能存在TLR2功能的变化。本研究填补了海南地方猪TLR2基因多态性空白,为深入研究TLR2基因多态性与猪疫病易感性的关系提供基础研究资料。     

Haplotype diversity in MC1R locus between the Min and white-haired pig breeds

In this article, we investigated the genetic variations in the coding region of porcine melanocortin receptor 1 (MC1R) gene in three pig breeds (Min, Yorkshire and Landrace) with black and white coat colors. Six polymorphic sites were found to be significantly associated with coat color. Two blocks were identified in the linkage disequilibrium map, the haplotypes in the first block are nt67/68indelCC and nt67/68indel--, and the haplotypes in the second block are ACCGA and GTTAG. The median-joining network diagram of MC1R haplotypes showed most Min pigs and other Asia domestic breeds own similar haplotypes to ACCGA, while the haplotypes of Europe pig breeds are similar to GTTAG. The phylogenetic analysis of the MC1R CDS further showed Min pigs are close to Laiwu pigs (Shandong, China), which indicated that the black coat color trait of Min pig might be originated and evolved from the black pig breed in Shandong Peninsula of China.     

江西地方猪种SLA-DRB基因外显子2的多态性研究

采用PCR-RFLP法对3个江西地方猪种(乐平花猪、修水杭猪和万安花猪)的SLA-DRB基因外显子2的PCR产物进行多态性分析。通过限制型内切酶RsaⅠ酶切后,共产生9种组合带型。通过检测发现:乐平花猪有8种组合带型,即AA、AB、AC、BB、BC、BD、CD和DD;修水杭猪有3种组合带型,即AA、AB和AC;万安花猪有4种组合带型,即AA、AC、BC和CC,且3个猪种中均以A为优势带型,在猪种中频率相差不大。χ2检测表明,乐平花猪和修水杭猪SLA-DRB基因外显子2在RsaⅠ酶切位点达到了Hardy-Weinberg平衡状态,而万安花猪未达到Hardy-Weinberg平衡状态。     

Stimulation of pig growth performance by porcine growth hormone and growth hormone-releasing factor

The current study was undertaken to determine the effects of human growth hormone-releasing factor [hpGRF-(1-44)-NH2] on growth performance in pigs and whether this response was comparable to exogenous porcine growth hormone (pGH) treatment. Preliminary studies were conducted to determine if GRF increased plasma GH concentration after iv and im injection and the nature of the dose response. Growth hormone-releasing factor stimulated the release of pGH in a dose-dependent fashion, although the individual responses varied widely among pigs. The results from the im study were used to determine the dose of GRF to use for a 30-d growth trial. Thirty-six Yorkshire-Duroc barrows (initial wt 50 kg) were randomly allotted to one of three experimental groups (C = control, GRF and pGH). Pigs were treated daily with 30 micrograms of GRF/kg body weight by im injection in the neck. Pigs treated with pGH were also given 30 micrograms/kg body weight by im injection. Growth rate was increased 10% by pGH vs C pigs (P less than .05). Growth rate was not affected by GRF; however, hot and chilled carcass weights were increased 5% vs C pigs (P less than .05). On an absolute basis, adipose tissue mass was unaffected by pGH or GRF. Carcass lipid (percent of soft-tissue mass) was decreased 13% by GRF (P less than .05) and 18% by pGH (P less than .05). Muscle mass was significantly increased by pGH but not by GRF. There was a trend for feed efficiency to be improved by GRF; however, this was not different from control pigs. In contrast, pGH increased feed efficiency 19% vs control pigs (P less than .05). Chronic administration of GRF increased anterior pituitary weight but did not affect pituitary GH content or concentration. When blood was taken 3 h post-injection, both GRF- and pGH-treated pigs had lower blood-urea nitrogen concentrations. Serum glucose was significantly elevated by both GRF and pGH treatment. This was associated with an elevation in serum insulin. These results indicate that increasing the GH concentration in blood by either exogenous GH or GRF enhances growth performance. The effects of pGH were more marked than for GRF. Further studies are needed to determine the optimal dose of GRF to administer in growth trials and the appropriate pattern of GRF administration in order to determine whether GRF will enhance pig growth performance to the extent that exogenous pGH does.     

我国地方猪品种-乌金猪的生理特性研究

对生长在海拔1172.5m的云南省威信县的乌金猪进行生长发育、生产性能以及生理指标的测定。乌金猪的体温为(39.03±0.34)℃,呼吸频率为(28.30±2.31)次/min,脉搏频率为(82.87±3.65)次/min;15min、30min、45min、60min、2h、24h的血沉值分别为(2.67±0.88)mm、(5.33±1.54)mm、(9.87±2.33)mm、(15.07±3.34)mm、(29.43±4.07)mm、(98.10±9.98)mm;血红蛋白含量为(158.00±21.00)g/L,红细胞含量为(6.00±0.39)×1012个/L,白细胞含量为(12.36±1.18)×109个/L,嗜酸性白细胞含量为(2.40±0.39)×108个/L,血小板数为(23.03±3.12)×1010个/L。白细胞分类计数:嗜酸性白细胞占(3.14±0.86)%,嗜碱性白细胞占(0.60±0.77)%,嗜中性晚幼白细胞占(0.00±0.00)%,嗜中性杆状核白细胞占(3.03±0.62)%,嗜中性分叶核白细胞占(33.90±3.25)%,淋巴细胞占(55.83±3.42)%,单核细胞占(3.50±0.63)%。     

不同品种猪IGFBP-3启动子区突变位点筛查及分析

以军牧1号白猪、大白猪、东北野猪、巴马香猪和西藏小型猪为研究对象,通过PCR扩增5个品种猪IGFBP-3基因5′调控区序列(约2 000bp)并进行测序分析,来研究不同品种猪IGFBP-3基因启动子区序列的差异。同源性比对分析发现5个品种猪IGFBP-3基因5′调控区存在约50处突变;启动子预测发现在-185bp附近为核心启动子区的几率最大;突变共导致9处转录因子结合位点发生改变,其或可造成不同品种猪IGFBP-3表达量的差异,进而影响不同品种猪的体型大小。     

猪品种遗传多样性的研究进展

从猪品种的体型外貌、染色体带型、血型和蛋白质以及DNA分子水平等几个方面对猪的遗传多样性进行论述 ,并对遗传多样性的度量参数作了分析。认为猪种遗传多样性的研究是保种和利用的理论基础 ,从形态到DNA分子水平对猪品种遗传多样性的研究在遗传资源大量流失的今天具有重要意义。     

6个猪种FUT1基因的多态性分析

α(1,2)岩藻糖转移酶基因1(α-1,2-Fucosyltransferase gene,FUT1)是可以调节大肠杆菌F18侵染猪小肠、并引起仔猪水肿和腹泻的一个抗性基因。采用PCR-SSCP方法,检测了FUT1基因在大白猪、长白猪、杜洛克、马身猪、山西黑猪、晋汾白猪6个猪种中的多态性。结果表明:在大白猪、长白猪和杜洛克这3个引进品种中,存在A、B、C 3种单倍型,A单倍型的平均分布频率为0.58;而在地方品种马身猪及其培育品种山西黑猪和晋汾白猪中只发现了单倍型A。经测序比对发现B单倍型第5位碱基发生了C→A的转换,第145个碱基处发生了T→C的突变;而单倍型C的第372位碱基A发生缺失。大白和杜洛克2个种群Hardy-Weinberg不平衡,FUT1基因在国外引进猪种大白、长白、杜洛克种群多态性丰富。     

三个贵州地方猪品种SERPINA3基因拷贝数变异的多态性研究

为了研究地方猪品种SERPINA3基因拷贝数变异(Copy Number Variation,CNV)的多态性变化,采用实时荧光定量PCR方法,对香猪、糯谷猪和柯乐猪3个贵州地方猪品种的SERPINA3基因的拷贝数进行了分析,并与大白猪相比较。结果显示,在4个猪品种中,SERPINA3基因的拷贝数均以增加为主,香猪的SERPINA3基因的拷贝数最少,为10.45±0.37,大白猪的拷贝数最多,达18.02±0.92,糯谷猪与柯乐猪分别为14.40±0.94、14.05±0.91。其中香猪、糯谷猪和柯乐猪3个贵州地方猪品种的SERPINA3基因拷贝数与大白猪相比差异极显著(P0.01),糯谷猪与柯乐猪之间的差异不显著(P0.05),糯谷猪和柯乐猪与香猪相比差异极显著(P0.01)。结果提示:SERPINA3基因的拷贝数在猪品种之间存在丰富的多态性变化。     

Stimulation of pig growth performance by porcine growth hormone: determination of the dose-response relationship

The present study was undertaken to determine the relationship between dose of porcine growth hormone (pGH) and growth performance of pigs. Porcine GH was administered daily for 35 d [buffer-injected control = (C); 10 micrograms/kg body weight (BW) = (L); 30 micrograms/kg BW = (M); 70 micrograms/kg BW = (H)] to barrows (initial wt = 50 kg). Growth rate was significantly increased by pGH (14% for H dose vs C). Feed efficiency was increased in a dose-related manner (L = 7%, M = 10%, H = 17%) by pGH. There was a concurrent change in carcass composition of pGH-treated pigs. The H dose of pGH decreased the percentage of carcass lipid by 25% (P less than .05). Muscle mass was significantly increased in H vs C pigs (31 vs 26 kg). Serum insulin-like growth factor 1 (IGF-1) concentration increased in a manner that was linearly related to the pGH dose (r = .87). No antibodies to pGH were detected in any of the pigs. In summary, these results extend our earlier findings that pGH increases growth performance markedly. Based on the present findings it appears that the maximally effective dose of pGH is greater than 70 micrograms.kg BW-1.d-1 since several indices of the growth-promoting and metabolic effects of pGH (% carcass protein, % carcass lipid and feed efficiency) had not plateaued.