氟烷基因PCR-RFLP检测技术在杜洛克猪和长白猪中的应用

采用PCR-RFLP技术检测了51头杜洛克猪和30头长白猪氟烷基因基因型的分布情况。结果表明，在检测的杜洛克和长白猪群体中氟炕基因显性纯合子频率分别为0．843和0．933．杂合子频率为0．157和0．067，没有发现氟炕基因隐性纯合子。     

氟烷基因型PCR—RFLP诊断技术在种猪性能测定中应用

在国内首先将氟烷基因型ＰＣＲ－ＲＦＬＰ诊断技术用于种猪性能测定中心的种猪测定。通过从猪毛、猪血中提取的ＤＮＡ，用特异性的引物进行ＰＣＲ扩增均能得到６５９ｂｐ的ＤＮＡ片断，并用ＨｈａⅠ内切酶消化ＰＣＲ产物，酶切结果能准确检测猪应激综合症，即ＲＹＲ１基因（氟烷基因）的突变。在测定的长白、约克、杜洛克猪中，发现长白猪Ｈａ１＾ｎ基因基因频率较其它品种高，为９．０％，杜洛克为４．２％，在大约克中未发现。     

丹系长白猪恶性高温综合症（pMHS）基因的检测分析

采集91头丹系长白种猪耳组织样品，用高盐法提取DNA，特异性扩增包含C1843在内的CRC／RYR1660bp片段，用HhaⅠ进行直接酶切，根据电泳图谱确定MHS基因座位上的基因型。结果表明91头丹系长白猪中，杂合猪（MHSN／MHSn）为10头，占10.98％，纯合阴性猪81头占89.02％，没有发现纯合阳性猪。MHSN和MHSn的基因频率分别为0.9451和0.0549。结合国内已有的测定结果，认为目前我国丹系长白猪群中MHSN及MHSn的基因频率分别为0.9086和0.0914。     

应用PCR检测猪氟烷基因的研究

应用PCR－RFLP技术对云南省原种猪场核心群中88头引进外种猪（长白31头，大白59头）进行了氟烷基因的检测，结果检出9头杂合子，未发现阳性猪（nn）。研究表明：（1）长白猪群中不存在氟烷基因；（2）大白群中有9头杂合子且呈现全同胸或父系半同胞；（3）用猪毛进行氟烷基因检测具有方便、减少应激、准确性高等特点。     

丹系长白猪恶性高温综合性（pMHS）基因的检测分析

采集91头丹系长白种猪耳组织样品，用高盐法提取DNA，特异性扩增包含C1843在内的CRC／RYR1660bp片段，用HhaI进行直接酶切，根据电沪图谱确定MHS基因座位上的基因型。结果表明：91头丹系长白猪中，杂合猪（MHS^N/MHSn)为10头，占10.98%,纯合阴性猪81头占89.02％，没有发现纯合阳性猪。MHS^N和MHS^n的基因频率分别为0.9451和0.0549.结合国内已有的测定结果，认为目前我国丹系长白猪群中MHS^N MHS^n的基因频率分别为0.9086和0.0914.     

氟烷基因型PCR-RFLP诊断技术及其对我省种猪的检测

通过从猪毛、猪血中提取ＤＮＡ，用特异性的引物进行ＰＣＲ扩增均能得到６５９ｂｐ的ＤＮＡ片断，并用ＨｈａⅠ内切酶消化ＰＣＲ产物，酶切结果能准确检测猪应激综合症，即ＲＹＲ１基因（氟烷基因）的突变。在我省种猪场饲养的长白、大约克、杜洛克和川白Ⅰ系猪中，发现长白猪Ｈａｌｎ基因频率较其它品种高，为９４％，杜洛克为３７％，在大约克和川白Ⅰ系中未发现。     

撒坝猪及其配套系氟烷基园检测与遗传效应分析

利用ＰＣＲ－ＲＦＬＰ技术对云南省楚雄州种猪场１０４头种猪包括撒坝纯种７１头,加系大约克１０头,丹系长白８头,美系杜洛克９头及三元杂大长撒６头）进行了氟烷基因检测。发现杂合子猪（Ｎｎ）４头,包括２头大约克,２头大长撒,未发现阳性猪（ｎｎ）,其余皆为阴性（ＮＮ）。对大长撒氟烷基因杂合子与同群阴性猪作生长和肉质性状比较,显示其杂合子在瘦肉率、日增重和料重比等有优势,而肉质性状无明显差异。本文还就氟烷基因     

家猪13/17罗伯逊易位染色体遗传规律的研究

本研究采用微量全血培养法对１３／１７ 染色体易位猪的５ 种交配组合所产３４２ 头后代的染色体组型进行了分析。结果表明,家猪１３／１７ 罗伯逊易位染色体的遗传符合孟德尔遗传规律,且具有稳定的遗传性。１３／１７ 易位纯合子互交后代仍然为１３／１７ 易位纯合子;１３／１７ 易位杂合子互交后代出现１３／１７ 易位纯合子（２ｎ ＝ ３６） ,１３／１７ 易位杂合子（２ｎ ＝ ３７） 和正常核型家猪（２ｎ ＝ ３８） 三种核型,经卡方检验符合１ ２ １ 的理论比值。本文还讨论了家猪和野猪的染色体进化,１３／１７ 罗伯逊易位染色体的应用。     

辽宁种猪氟烷基因位点多态性分析

采用PCR—RFLP技术分析辽宁种猪氟烷基因（RYR1）多态性基因多态性,3个外国猪种氟烷基因HhaI酶切位点上都显示多态性,荷包猪未检测到多态性,优势基因型均为NN。试验结果表明,荷包猪群体均为氟烷阴性纯合子,外来猪种可见杂合子。     

氟烷基因型PCR-RFLP诊断技术在种猪性能测定中的应用

在国内首先将氟烷基因型PCR－RFLP诊断技术用于种猪性能测定中心的种猪测定。通过从猪毛、猪血中提取的DNA,用特异性的引物进行PCR扩增均能得到659bp的DNA片断,并用HhaⅠ内切酶消化PCR产物,酶切结果能准确检测猪应激综合症,即RYR1基因（氟烷基因）的突变。在测定的长白、大约克、杜洛克猪中,发现长白猪Ha1n基因基因频率较其它品种高,为9．0％,杜洛克为4．2％,在大约克中未发现。     

苏钟Ⅰ系和Ⅱ系猪的氟烷基因及其对产肉性能的影响

:对 3 0 1头瘦肉型新品系苏钟 系和 系仔猪进行氟烷测验 ,阳性率为 1 .3 3 %。随机抽取氟烷阴性猪 3 4头进行基因型检测 ,有 6头为杂合子 ,由此得知 NN、Nn和 nn3种基因型的频率分别为 81 .2 6%、1 7.4 1 %和 1 .3 3 %,N和 n2种基因的频率分别为 89.97%和 1 0 .0 3 %。对 3种基因型猪的肉质进行评定结果显示 ,4头氟烷阳性猪 ( nn)肉质最差 ,出现 3头严重 PSE肉和 1头轻度 PSE肉 ,而氟烷阴性猪 ( NN或 Nn)未发生 PSE肉。2 0头苏钟 系氟烷阴性猪用阳性公猪测交 ,对产出的 2 0 8头后代进行氟烷测验 ,共检出 4窝中的 2 1头阳性猪。对测交后代进行肥育性能和肉质测定 ,发现阳性猪的日增重和饲料报酬等较低 ,屠宰率、眼肌面积和瘦肉率较高 ,肉质较差     

军牧1号白猪、杜洛克猪和藏猪的氟烷基因和酸肉基因多态性分布

为了研究军牧1号白猪、杜洛克猪和藏猪氟烷基因和酸肉基因的多态性分布情况,试验采用PCR-RFLP方法对61头军牧1号白猪、51头杜洛克猪和51头藏猪的氟烷基因和酸肉基因多态性进行了检测。结果表明:军牧1号白猪的氟烷基因表现为单一的NN型;杜洛克猪的氟烷基因表现为多态性,等位基因N的频率为0.196 1,基因型分布符合哈代-温伯格平衡(χ2=3.033 9,P=0.081 5);藏猪的氟烷基因表现为单一的nn型。3个猪种的酸肉基因均表现为单一的rn/rn型。     

氟烷基因在四川省大约克夏猪中的分布

采用PCR -RFLP技术 ,检测了“九五”期间四川省绵阳市种畜场大约克夏猪选育群第四世代 10 3个个体的氟烷基因型 ,摸清了Haln 基因在该群体中的分布 ,Haln 基因频率为 2 .913%。检测结果为该场建立大约克夏猪应激抵抗群提供了科学依据     

应用聚合酶链式反应(PCR)技术检测野猪的氟烷基因

猪应激综合征(Procine Stress Syndrome,PSS)是指猪在应激因子的作用下发生恶性高热综合症(Malignant Hyperthermia Syndrome，MHS)。试验随机选取18头纯种野猪提取基因组DNA进行聚合酶链式反应，扩增得到RYR。基因特异片段，经过HhaⅠ酶切阳性鉴定可断定这18头猪的RYR1基因都没有发生突变，因此不存在猪应激综合征问题。     

Diminished expression of ACTH signaling proteins and steroidogenic limiting factors in adrenocortical cells isolated from halothane nn pigs

Previous studies demonstrated significantly lower plasma cortisol level in homozygous halothane-positive (Hal nn) pigs, as compared with homozygous halothane-negative (Hal NN) pigs. To determine whether such difference is attributed to the fundamental alterations in adrenocortical function, F1 offsprings from Pietrain (Hal nn)xErhualian (Hal NN) were intercrossed to produce F2 sibling pigs with segregated genotypes. Adrenocortical cells were isolated from the Hal nn and Hal NN F2 pigs, respectively, and cultured with or without ACTH challenge. Cortisol levels in culture medium, as well as the content of MC2R, cAMP, CREB, phosphorylated CREB (pCREB), StAR and P450scc in adrenocortical cell lysates, were determined. Cortisol, cAMP, StAR and P450scc levels were significantly lower in Hal nn adrenocortical cells under basal condition without ACTH challenge. ACTH significantly increased cortisol level in the medium and the protein content of MC2R, StAR, P450scc in adrenocortical cell lysates, regardless of genotypes. Total CREB protein content was not different between genotypes and treatments, whereas pCREB content exhibited significant effects of genotype and treatment, being higher in Hal NN than in Hal nn under basal condition and in response to ACTH challenge. These results indicate that the compromised cAMP/PKA/pCREB signaling pathway of ACTH and diminished expression of limiting factors in adrenocortical steroidogenesis (StAR and P450scc) may contribute to the significantly lower plasma cortisol levels in Hal nn pigs.     

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.     

山西地区6个猪种氟烷敏感基因的检测

采用PCR-RFLP技术对大白猪、长白猪、杜洛克猪、山西白猪、山西黑猪和马身猪等6个品种（系）482头猪进行了氟烷敏感（Hal）基因检测。结果表明,在山西黑猪和马身猪中,只检测到氟烷敏感阴性纯合子（NN）;而在长白猪、大白猪、杜洛克猪和山西白猪群体中,均检测到NN、Nn两种类型的个体,Haln的基因频率分别4.1%、1.8%、1.4%和1.7%。在今后的育种工作中,应加强对氟烷敏感基因的检测,选育抗应激群体。     

Effects of the halothane genotype and slaughter weight on texture of pork

The objective of this study was to investigate the effects of the halothane (HAL) genotype, slaughter weight (SW), and the HAL x SW interaction on compositional and textural traits of raw and cooked pork. Pigs were bred to exhibit one of the three HAL genotypes (NN, Nn, and nn) with otherwise equivalent genomes. The nn halothane reactors are known to typically produce PSE pork, whereas NN pigs do not typically produce PSE pork. Pietrain x Large White gilts and boars, all with verified Nn genotype (by DNA test), were mated to obtain F2 littermates of the three HAL genotypes. These pigs were slaughtered at either 101 +/- 3 ("light") or 127 +/- 3 ("heavy") kg BW and were evaluated for longissimus muscle traits. The pH at .5 h after death (pH1) was 6.35, 6.13, and 5.68 in NN, Nn, and nn pigs, respectively. Sarcomere length was greater in nn than in NN and Nn pigs (1.94 vs 1.83 and 1.85 microm, respectively). Mechanical resistance was higher in nn than in NN pigs for both raw and cooked meat. Meat from nn pigs was judged by a trained panel to be less rough, more cohesive, harder, more fibrous, less granular, more elastic, and less easy to swallow than meat from NN pigs. For most traits under study, the heterozygotes were intermediate between the homozygotes but closer to NN than to nn pigs. Muscle from heavy pigs had longer sarcomeres and less moisture than muscle from light pigs. The n allele of the HAL gene unfavorably affects pork texture, and this effect is maintained throughout the range of 101 to 127 kg BW.     

皮特兰猪的氟烷基因检测与分子选育

以PCR-RFLPs法为检测方法,针对氟烷基因开展无应激皮特兰猪的分子选育,共检测从2003-2007年若干世代共28批次皮特兰猪。结果显示,在所检测的共994头样本中,具NN基因型的为361头,具Nn基因型的为374头,具nn基因型的为259头。试验结果表明,随着世代选育的进展,群体中N基因和NN基因型的频率逐渐升高,至第17批次时均达100%,后均维持在较高水平,Hard-Weinberg平衡亦呈现平衡-不平衡-平衡的现象,直至此基因最终在群体中失去平衡。试验结果还表明,利用基因技术对家畜进行分子育种是可行的。     

Effects of transport stress on concentrations of cortisol, corticosteroid-binding globulin and glucocorticoid receptors in pigs with different halothane genotypes

Effects of stress on concentrations of cortisol and corticosteroid-binding globulin (CBG) in blood plasma and on glucocorticoid receptor concentrations in muscle cytosol were studied in pigs representing three Halothane (Hal) genotypes (NN, Nn, nn). At 12 wk of age, animals were divided into four groups: pigs subjected to transport (5 h in a truck), pigs treated with amperozide prior to transport, pigs not transported but treated with amperozide and pigs neither transported nor given amperozide. Animals were slaughtered the week they reached 100 kg live weight (3 mo later). The Hal gene showed no major influence on the variables studied except for cortisol concentrations (P = .06) measured directly after transport at 12 wk of age (NN = 66.8 nM, Nn = 61.4 nM, nn = 69.4 nM). However, the response in each Hal genotype differed, depending on whether or not the pigs had been exposed to transport. Two weeks after transport, NN pigs developed higher cortisol concentrations than untransported animals, whereas the response was reversed in nn animals; Nn pigs showed no difference in this regard. At slaughter, the effect of transport (12 wk of age) on cortisol and CBG was still apparent. In NN pigs cortisol and CBG concentrations were elevated (P less than or equal to .05, P = .08, respectively), whereas concentrations tended to be lower in nn pigs (P = .17, P = .07, respectively) when compared with untransported pigs. Transported pigs had lower receptor concentrations at slaughter (P less than or equal to .01) than untransported pigs. However, pigs given amperozide in connection with transport had a receptor concentration comparable to that in untransported pigs. Our study shows conclusively that transport stress had long-term effects on cortisol, CBG and glucocorticoid receptor concentrations. In addition, amperozide had long-term effects on cortisol and receptor concentrations.