西藏高原藏猪盲肠微生物群落结构与多样性的研究

本研究旨在探讨西藏高原放牧藏猪、舍饲藏猪与瘦肉型猪（杜×长×大，DLY猪）盲肠微生物的群落组成及多样性，从而部分揭示西藏高原藏猪肠道微生物的特异性。选用日龄相近的放牧藏猪、舍饲藏猪及DLY猪各5头，放牧藏猪由林芝本地农牧民采用传统方式放牧养殖，舍饲藏猪及DLY猪圈养并饲喂相同饲粮，160日龄时前腔静脉放血屠宰，采集盲肠食糜于液氮速冻待测。采用高通量测序技术测定样品16S rRNA V3-V4区域的基因序列。结果表明，在15个样本的16S rRNA基因V3-V4区测序共获得了659 904条有效序列，其中放牧藏猪213 031条、舍饲藏猪219 417条、DLY猪227 456条。放牧藏猪盲肠微生物OTU总数、Chao1指数、ACE指数及香农（Shannon）指数均显著高于舍饲藏猪与DLY猪（P<0.05），而舍饲藏猪与DLY猪无显著差异（P>0.05）。3个类型猪盲肠微生物共划分为13个门，56个属。厚壁菌门（Firmicutes）是3个类型猪相对丰度共同最高的门。放线菌门（Actinobacteria）与疣微菌门（Verrucomicrobia）在放牧藏猪中相对丰度显著高于其他2个类型猪（P<0.05），舍饲藏猪拟杆菌门（Bacteroidetes）相对丰度显著高于放牧藏猪与DLY猪（P<0.05）；放牧藏猪共有11个属相对丰度显著高于舍饲藏猪与DLY猪（P<0.05）。结果提示，放牧藏猪盲肠微生物群落结构与多样性具备自身独特性，为进一步开发藏猪资源提供参考。     

Study on the Cecal Microbial Community Structure and Diversity of Tibetan Pigs in Tibetan Plateau

The purpose of this study was to investigate the cecal microbial community composition and diversity of grazing Tibetan pigs, captive Tibetan pigs and lean type pigs (DLY pigs) in Tibetan plateau, in order to partially revealed the specificity of the intestinal microbial community of Tibetan pigs. Pigs with the same age were chosen, including 5 grazing Tibetan pigs, 5 captive Tibetan pigs and 5 DLY pigs. The grazing Tibetan pigs were free range husbandry by local herdsman. The captive Tibetan pigs and DLY pigs were reared in pens and fed with same diets. At the age of 160 days, all the pigs were slaughtered by anterior vena cava bloodletting. Cecal chyme was collected and rapidly frozen with liquid nitrogen. The V3-V4 regions of the 16S rRNA genes were amplified and sequenced using high-throughput sequencing techniques. The results showed that a total of 659 904 valid sequences were obtained from the V3-V4 region of 16S rRNA in 15 samples, including grazing Tibetan pigs 213 031, captive Tibetan pigs 219 417 and DLY pigs 227 456. Interestingly, the cecal OTUs quatity, Chao1 index, ACE index and Shannon index of the grazing Tibetan pigs were significantly higher than those of the other pigs (P<0.05), but there was no significant difference between the captive Tibetan pigs and DLY pigs (P>0.05). The microbiota of 3 types of pigs were divided into 13 phyla and 56 genera, and Firmicutes has the highest relative abundance in all pigs. The relative abundance of Actinobacteria and Verrucomicrobia were significantly higher in grazing Tibetan pigs than those of the others (P<0.05), but Bacteroidetes was remarkably higher in captive Tibetan pigs (P<0.05). The relative abundance of 11 genera in grazing Tibetan pigs was significantly higher than captive Tibetan pigs and DLY pigs (P<0.05). These results indicated that the cecal microbial community structure and diversity of grazing Tibetan pigs were unique, which could provide reference for further developing the Tibetan pig resources.     

藏猪与杜洛克猪血液中胰岛素样生长因子-1（IGF-1）含量差异研究

为了解国内、外两类猪种肌肉生长发育及血清中相关细胞因子含量差异,以我国特有的藏猪和国外杜洛克猪作为研究对象,采用酶联免疫分析法（ELISA）测定6月龄藏猪、杜洛克猪血清中胰岛素样生长因子-1（IGF-1）的含量及肌纤维面积。结果显示：藏猪血清中IGF-1含量及肌纤维面积均极显著低于杜洛克猪（P＆lt;0.01）,且两者呈极显著正相关,说明IGF-1是促进猪生长发育特别是背最长肌生长发育的一个重要因素。     

二花脸猪和杜洛克猪的RAPD分析

利用６０个随机引物对二花脸猪（太湖猪的一个类群）和杜洛克猪的基因组ＤＮＡ进行ＲＡＰＤ分析,其中４８个引物可扩增出清晰的ＲＡＰＤ带型,８个引物可扩增出多型式片段。一个引物（ＯＰＢ１３）可在两品种间扩增出一条稳定的重复性好的多态片段,其大小约为１８９０ｂｐ。结果表明,二花脸猪、杜洛克猪群内遗传距离指数分别为０．０３７１、０．０３４５,遗传多样性指数分别为０．４８６、０．４３１,两品种间存在着ＤＮＡ分子     

二花脸猪的高分辨显带核型研究

采用MTX或TdR细胞同步化技术制备了早中期染色体,并应用G-,R-,C-,DA/DAPI显带和银染技术,研究了二花脸猪的高分辨显带核型,其主要结果如下:1.G-带和R-带带型与其它家猪的带型相似,但C-带和Ag-NORs存在多态性;2.Ag-NOR定位于No.7和No.10染色体上;3,DA/DAPI带与端着丝粒染色体C-带相对应。此外,绘制了G带核型模式图,并讨论了染色体的分组及排列、G带带型的一致性、着丝粒异染色质的异质性和Ag-NOR频率与品种的关系。     

长白猪、北京黑猪及东北民猪脂肪酸及氨基酸组成

本文测定了长白猪、北京黑猪及东北民猪背最长肌脂肪酸及氨基酸的组成。结果表明：１，长白猪总饱和脂肪酸含量显著高于北京黑猪（Ｐ＜０．０５）及民猪（Ｐ＜０．０５），北京黑猪显著高于民猪（Ｐ＜０．０５）；民猪的总不论和脂肪酸含量显著高于长白猪（Ｐ＜０．０５），与北京黑猪差异不显著（Ｐ＞０．０５）；不同性别猪各脂肪酸含量差异不显著，２，３个猪种中１５种氨基酸及衍生物含量有显著差异（Ｐ＜０．０５）。民猪和北京黑猪赖氨酸的含量显著高于长白猪，北京黑猪苏氨酸含量低于长白猪（Ｐ＜０．０５）。不同性别个体间游离氨基酸组成除丝氨酸、缬氨酸、苯丙氨酸外，没有显著差异（Ｐ＞０．０５）。     

不同体重阶段川藏黑猪和杜长大猪肌肉中氨基酸含量研究

为了研究不同猪种背最长肌中氨基酸沉积规律,试验采用高效液相色谱检测了不同体重梯度（90、110和130 kg）的川藏黑猪和杜长大（DLY）猪背最长肌中氨基酸含量。结果表明,谷氨酸在两猪种肌肉中含量最高,含硫氨基酸总量在90和130 kg体重梯度时表现为川藏黑猪显著高于DLY猪（P〈0.05）,110 kg体重梯度时极显著高于DLY猪（P〈0.01）,而同一猪种不同体重梯度间各种氨基酸组成差异均不显著（P〉0.05）,鲜味氨基酸占总氨基酸比例（FAA/TAA）在90 kg体重梯度表现为川藏黑猪极显著高于DLY猪（P〈0.01）,130 kg体重梯度时显著高于DLY猪（P〈0.05）。本研究说明川藏黑猪肌肉中与风味相关的氨基酸含量高于DLY猪,我们认为这也是川藏黑猪的肌肉风味比DLY猪更浓郁的重要原因之一。我们的研究初步揭示了不同猪种背最长肌中氨基酸的沉积规律及构成差异,为进一步研究猪肉风味形成机理提供数据。     

湘岭猪不同世代、不同屠宰体重胴体性状和肌肉品质测定分析

试验旨在探讨不同世代、不同屠宰体重湘岭猪胴体性状和肌肉品质的差异。试验选择体重140 kg左右的湘岭猪Ⅰ世代阉公猪4头(组4),进行屠宰测定和肉质评定。另选择前期屠宰的零世代14头湘岭猪的屠宰测定数据作为对照,按宰前活重分为3组,分别为90 kg组(组1)、100 kg组(组2)、125 kg组(组3)。结果表明:1)胴体性状:胴体重、屠宰率、胴体长、三点平均背膘厚和脂率这5个指标有随着屠宰体重的增加而增加的趋势,后腿比有随着屠宰体重的增加而呈降低的趋势。三点均皮厚组4最高,极显著高于其他3组(P<0.01);瘦肉率以组2最高,以组4最低,组4显著或极显著低于其他3组。骨率以组3最低,组1最高,组1极显著高于组2和组3(P<0.01),组4显著高于组3(P<0.05)。2)肉品质:b1h值以组1最低,组2最高,组1显著低于组3和组4(P<0.05);pH24以组4最低,显著低于其他3组(P<0.05);贮存损失以组3最低,组1最高,组1显著高于组2和组3(P<0.05);失水率以组4最低,组2最高,组4极显著低于组2,显著低于组1;熟肉率组1显著高于组2(P<0.05)。综上所述:在这次试验条件下,胴体性状以零世代中90 kg组和100 kg组较好,Ⅰ世代中140 kg组较差;肌肉品质各组均有优劣,整体以零世代中90 kg组和Ⅰ世代中140 kg组较好。     

不同品种猪PBD-124基因多态性及差异表达研究

【目的】 克隆获得猪β-防御素-124（porcine beta-defensin-124,PBD-124）基因CDS区并探究其多态性,分析PBD-124基因在不同品种猪及同种猪不同组织内的表达情况。【方法】 采用RT-PCR方法扩增并克隆猪PBD-124基因CDS区,利用PCR-RFLP酶切法对大白猪、民猪和野杂猪PBD-124基因的Bln Ⅰ酶切位点进行多态性检测,利用实时荧光定量PCR方法检测该基因在不同品种猪肝脏、脾脏和血液内的表达差异。【结果】 试验成功克隆出猪PBD-124基因CDS区,长423 bp,共编码140个氨基酸,测序结果发现其存在c.257 G>A和c.263 T>G 2个突变位点,因2个突变位点间隔过近,可能存在连锁,仅对第1个突变位点进行酶切,大白猪中检测到GG、GA、AA 3种基因型,而民猪和野杂猪中仅检测到GA和AA 2种基因型,3个群体中AA基因型均为优势基因型,大白猪、民猪和野杂猪的AA基因型频率分别为0.5261、0.9412和0.6452,且3个群体均处于Hardy-Weinberg平衡（P>0.05）。3个群体的多态性均不高,大白猪处于中度多态（0.25<PIC<0.5）,民猪和野杂猪则处于低度多态（PIC<0.25）。实时荧光定量PCR结果显示,PBD-124基因在大白猪、民猪、野杂猪的脾脏、肝脏及血液中均有表达,且存在表达差异。【结论】 猪PBD-124基因CDS区长423 bp,共编码140个氨基酸,与参考序列比对发现2个突变位点,均未引起氨基酸突变;3个群体多态性均不高;PBD-124基因在不同品种猪及同种猪不同组织间表达均存在差异。     

山猪及其杂种黑猪的肥育性能与肉质测定

为探明以山猪为素材的优质商品猪的杂交生产模式,研究选用杜洛克和巴克夏为父本与山猪母本杂交产出的杜山和巴山后代,以及山猪为父本再与杜山、巴山母本回交产出的山杜山和山巴山后代,以纯种山猪为对照,对以上含1/2、3/4山猪血统的商品猪的生长速度、饲料报酬、胴体与肉质等方面进行分析比较。结果表明:杜山和巴山二元杂种猪分别比纯种山猪日增重提高48.5%(P0.01)和45.4%(P0.01);杜山和巴山的背膘厚显著低于纯种山猪(P0.05),眼肌面积高于山杜山(P0.05)、山巴山(P0.05)和纯种山猪(P0.01);杜山的瘦肉率高于巴山(P0.05)、山杜山(P0.05)、山巴山(P0.01)和纯种山猪(P0.01);纯种山猪的大理石纹评分高于杜山(P0.05)和巴山(P0.01);失水率以巴山最高,极显著高于山杜山和纯种山猪(P0.01);纯种山猪的熟肉率高于杜山(P0.01)、巴山(P0.01)、山杜山(P0.05)和山巴山(P0.05);所有营养成分指标间差异均未达到显著水平。综合所有测定结果,二元杂交组合杜山优于巴山,回交组合山杜山也优于山巴山。     

梅山猪与西方猪生长性能和胴体特性的比较研究

综述了梅山猪与西方猪生长性能和胴体特性的比较研究.结果表明梅山猪主要以生长性能差和脂肪组织高度发育为特性,梅山猪与西方猪相比,具有显著较低的日增重、采食量和瘦肉组织百分率以及较高的饲料转化率和背膘厚度,但梅山猪的肉质优于欧洲猪的.     

不同地方猪重要经济性状关联位点SNP芯片分型及群体遗传结构研究

旨在分析四川省7个地方猪种类群和山东省徒河黑猪重要经济性状关联SNP位点基因型分布及群体间遗传结构。本研究采用中芯一号芯片对23头成华猪、26头雅南猪、60头青峪猪、57头内江猪、151头丫杈猪、57头乌金猪（凉山类群）、51头平原藏猪、109头高原藏猪和28头徒河黑猪共562头健康种猪进行了单核苷酸多态性（single nucleotide polymorphism,SNP）分析,利用Plink软件对获得的基因型数据进行质控,结合R等软件,统计分析猪7个重要经济性状的基因型;采用Mega X软件进行聚类分析,使用Plink软件进行主成分（PCA）分析,通过VCFtools软件计算猪群间的群体遗传分化指数（Fst）,分析群体间遗传关系远近。结果显示,四川省地方猪群体中,采食量、酸肉和应激性状的非优势基因型比例均在2.20%以下;抗仔猪腹泻、料重比（FCR）、公猪精液品质和多肋性状的非优势基因型比例分别为8.99%、11.80%、73.97%和95.32%;徒河黑猪群体中,应激性状已无q等位基因,采食量和酸肉性状的非优势基因型比例较低,均为3.57%;公猪精液品质、抗仔猪腹泻、料重比和多肋性状的非优势基因型比例较高,分别为39.29%、50.00%、82.14%和92.86%;聚类和主成分分析显示,徒河黑猪与四川地方猪种间遗传距离远,丫杈猪、乌金猪、内江猪和藏猪（平原和高原）各自聚为一类,品种间群体分层结构明显,雅南猪、成华猪、青峪猪聚为一类;Fst指数计算结果表明,同属于湖川山地猪的丫杈猪和青峪猪间存在高度遗传分化。结果提示,四川省地方猪群体的采食量、酸肉、应激、抗仔猪腹泻和料重比性状的非优势基因型比例较低,公猪精液品质和多肋性状的非优势基因型比例较高;徒河黑猪群体的应激性状已无q等位基因,采食量和酸肉性状的非优势基因型比例较低,公猪精液品质、抗仔猪腹泻、料重比和多肋性状的非优势基因型比例较高;群体遗传结构研究结果表明,丫杈猪与青峪猪都归类于湖川山地猪有待商榷。     

贵州白香猪与3种杂交猪脏器系数及血液生理指标比较

试验对贵州白香猪及贵州白香猪与大约克猪、杜洛克猪、长白猪3种杂交猪的体重、脏器系数和血液生理指标进行了比较。结果显示,贵州白香猪体重极显著低于3种杂交猪（P＜0.01）;贵州白香猪的脏器指标除心脏外与3种杂交猪均存在差异;贵州白香猪红细胞总数(RBC)和红细胞压积(HCT)极显著高于大约克猪×香猪（YX）（P＜0.01）;贵州白香猪的平均红细胞血红蛋白浓度(MCHC)、白细胞中淋巴细胞数量(LYM)、白细胞中淋巴细胞比率(LYM,%)及白细胞中中性粒细胞比率(GRA,%)与长白猪×香猪（LX）间存在显著差异（P＜0.05）。     

HABP4基因在大白猪和莱芜猪杂交一代中表达量差异研究

采用实时荧光定量PCR技术检测透明质酸接合蛋白（HABP4）基因在大白猪和莱芜猪2种杂交子代背最长肌组织中的表达水平差异情况。试验结果表明,HABP4基因在所检测的背最长肌组织中均有表达。且在2种杂交一代背最长肌组织中的表达水平有所不同。HABP4基因的表达量在正交一代的背最长肌中显著高于反交一代。本试验为猪屠宰性状的改良提供了分子遗传学依据,并为深入研究不同品种猪体内HABP4基因的生物学作用及作用机制奠定了基础。     

An analysis of mortality in the grower/finisher phase of swine production in the United States

Over a 6-month period, the mean mortality risk (based on 393 operations participating in the United States National Animal Health Monitoring System 1995 National Swine Study, and representing operations with ≥ 300 market hogs in 16 states), was 2.3 ± 0.2% in the grower/finisher production phase (where figures after the ± represent the standard error of the estimate). Mortality ≥ 4% was experienced by 13.5 2.9% of grower/finisher operations, while 63.6 ± 5.3% had ≤ 2% mortality. To identify factors associated with ≥ 4% mortality, stepwise logistic regression [Statistical Analysis Systems, (1989). SAS/STAT^® User's Guide, Version 6, 4th edn, Vol. 2. SAS Institute, Cary, NC, 794 pp.]was performed twice: once using operations with all mortality rates, and again excluding operations with between 2% and 4% mortality. Final models were run with SUDAAN [Shah, B.V., Barnwell, B.G., Bieler, G.S., (1996). SUDAAN User's Manual, Version 6.40, 2nd edn. Research Triangle Institute, Research Triangle Park, NC, 492 pp.] to take the sample design into account. In addition, SAS and SUDAAN logistic regression models were developed to analyze factors associated with > 2.3% mortality among grower/finisher pigs. Mean weaning age ≤ 28 days entered all models as being associated with increased mortality in the grower/finisher unit. Not obtaining all grower/finisher pigs from farrowing units belonging to the operation was associated with ≥ 4% mortality among grower/finisher swine. Not typically giving grower/finisher pigs antibiotics or other agents as disease-preventives or growth-promotants in the feed or water, and ranking producer organizations as very or extremely important sources of antibiotic information were associated with ≤ 2.3% mortality in the grower/finisher phase.     

滇南小耳猪与DLY商品猪背最长肌营养成分比较分析

本试验为比较研究滇南小耳猪与DLY商品猪肉的营养价值,分别检测了53头滇南小耳猪和58头DLY猪背最长肌肉的水分、粗蛋白质、粗脂肪、灰分、氨基酸及脂肪酸等营养成分含量,比较分析其差异性。结果显示,滇南小耳猪背最长肌的水分含量极显著低于DLY商品猪背最长肌（P < 0.01）,粗蛋白质、粗脂肪含量极显著高于DLY商品猪（P < 0.01）,灰分含量差异不显著（P > 0.05）;其中滇南小耳猪背最长肌的7种必需氨基酸（苏氨酸、缬氨酸、蛋氨酸、异亮氨酸、亮氨酸、赖氨酸、苯丙氨酸）、肉豆蔻酸、棕榈酸、油酸、顺式异油酸、11-顺-二十碳烯酸,饱和脂肪酸、单不饱和脂肪酸、总脂肪酸含量均极显著高于DLY商品猪（P < 0.01）。综上所述,滇南小耳猪与DLY猪相比具有更高的营养价值和开发价值。     

Nutrient Composition Comparison of Longissimus Dorsi between Diannan Small-ear Pigs and DLY Commercial Pigs

This study was conducted to compare the nutrient composition of longissimus dorsi between Diannan Small-ear pigs and DLY commercial pigs.53 Diannan Small-ear pigs and 58 DLY commercial pigs were chosen and longissimus dorsi samples were collected to determine the content of moisture,crude protein,crude fat,ash,amino acids and fatty acids.The results showed that the moisture content of Diannan Small-ear pigs was extremely significantly lower than DLY commercial pigs (P < 0.01).However,the content of crude protein and crude fat were extremely significantly higher than DLY commercial pigs (P < 0.01).And there was no significant difference in ash content (P > 0.05).The levels of threonine,valine,methionine,isoleucine,leucine,lysine and phenylalanine in longissimus dorsi of Diannan Small-ear pigs were extremely significantly higher than that of DLY commercial pigs (P < 0.01),and the content of myristic acid,palmitic acid,oleic acid,cis different oleic acid,11-cis-20 carbon olefine acid,saturated fatty acids,monounsaturated fatty acids and the total fatty acids in longissimus dorsi of Diannan Small-ear pigs were also extremely significantly higher than that of DLY commercial pigs (P < 0.01).In conclusion,Diannan Small-ear pigs had a better value in nutrient and development.     

Pneumocystis carinii in large domestic animals in Denmark. A preliminary report

By microscopic examination of toluidine blue O stained autopsy lung imprints Pneumocystis carinii was shown in 6 calves out of 160 (3.8%), in 1 sheep out of 28 (3.6%) and in 8 pigs out of 119 (6.7%). This is the first report of Pneumocystis carinii in calves, sheep and pigs in Denmark.     

Ochratoxin A as a suppressor of mitogen-induced blastogenesis of porcine blood lymphocytes

The in vitro effect of ochratoxin A on pig lymphocytes stimulated by the mitogen Concanavalin A was studied by measuring the rates of ³H-thymidine incorporation in DNA.Ochratoxin A inhibited the mitogenic response to Concanavalin A in a dose dependent way. An almost total inhibition was obtained with ≥ 1 mg ochratoxin A/1, approximately 60 % inhibition was produced by 0.5 mg ochratoxin A/1 and approximately 10 % inhibition by 0.06 mg ochratoxin A/1.The immunosuppressive effect of ochratoxin A was not altered much by different contents of bovine serum albumin, 0.1 or 0.3 %, in the cell culture medium.     

Faecal pH throughout the reproductive cycle of sows in commercial pig herds

Despite the importance of swine intestinal health, there are no easy-to-use and cost-efficient methods to evaluate it under field conditions for sows. To provide some indication about intestinal health, pH of faeces could be used but reference values for the currently high-performing commercial sow breeds are missing. In response, faecal pH of healthy sows from three different herds (herd A: 230 sows, herd B: 350 sows, herd C: 500 sows) was measured throughout the reproductive cycle. Within each herd, 10 sows were selected and rectal faeces samples were collected at different time points during the reproductive cycle: day 90 of gestation, day 1, 7, 14 and 21 of lactation, 7 days post-weaning and day 30 of the next gestation. In addition, data on sow body condition (back fat), feed composition and coarseness of the feed were collected. For individual pH measurements, the pH ranged from 6.30 to 7.93. However, for all herds together, the average faecal pH value of the sows throughout the reproductive cycle ranged from 6.89 to 7.15. Also, the variations due to sow and time of sampling during the reproductive cycle were low with coefficients of variation of less than 5%. The results from the pairwise comparisons of the statistical model showed that in the last stages of lactation (i.e., at day 21), significantly lower average pH values (p ≤ .05) are expected when compared to earlier stages of lactation (days 3 or 7), or at day 7 post-weaning or compared to day 30 of the next gestation. Bearing its limitations, our study provided reference faecal pH values from high-performing commercial sows under field conditions and as such they could be used directly in the field. Yet, further research is needed to provide more information on the factors affecting pH values throughout the reproductive cycle of the sow.