贵州白洗猪主要病毒病疫苗免疫效果分析

白洗猪是贵州省优良地方畜禽品种之一,以中小规模和散养为主,疫病对白洗猪遗传资源保护影响较大。本研究于2020—2023年对白洗猪4种主要病毒性传染病免疫效果进行定期监测,并汇总分析不同条件下的免疫效果、影响因素,旨在为白洗猪疫病防控提供理论参考,更好保护和利用这一地方品种猪。结果表明,强制免疫病种猪瘟、猪口蹄疫免疫效果较好,抗体合格率均超过70%,达到免疫抗体合格率标准;非强制免疫病种猪繁殖与呼吸综合征、猪伪狂犬病抗体合格率较低,分别为10.58%、34.75%。因此,应加大宣传力度,提高猪群疫病防控水平,引导基础设施薄弱、规模较小的养殖场积极开展猪繁殖与呼吸综合征、猪伪狂犬病等疫苗接种工作。

白洗猪与杜洛克猪杂交F1代猪肉品质特性研究

为探究白洗猪与杜洛克猪杂交后代体尺指标、胴体性状及肉品质变化,本试验选择10月龄健康白洗猪16头、白洗猪×杜洛克猪杂交F1代(DBF1)6头测定其体尺指标、屠宰性能及肉品质性状。结果显示,DBF1猪各项体尺指标与白洗猪相比差异不显著(P>0.05),眼肌面积(28.33cm2)、肉色(3.00)、大理石纹(3.50)依然保持在较好水平,不饱和脂肪酸含量(64.33%)、肌内脂肪含量(4.08%)与腿臀比(31.32%)均有所上调,背膘厚(24.69mm)、鲜味氨基酸总量(48.46%)显著或极显著下降(P<0.05;P<0.01),肌肉嫩度及保水能力显著降低(P<0.05)。白洗猪与杜洛克猪杂交后,可在保持其良好的产肉性能、较好的肌肉感官指标和肌纤维嫩度等情况下,提高其后躯载肉性能、瘦肉率及氨基酸种类等,但杂交后肌肉嫩度、营养价值、鲜味、保水能力等方面有所下降。

白洗猪PID1基因克隆及序列分析

本研究旨在对白洗猪磷酸酪氨酸互作结构域1(phosphotyrosine interaction domain containing 1,PID1)基因进行克隆和生物信息学分析。采用Nest PCR及T克隆技术对白洗猪PID1基因进行克隆测序,运用生物学分析软件分析其结构功能及其在种内及种间的遗传进化关系。结果表明,白洗猪PID1基因CDS区全长654bp,编码217个氨基酸,白洗猪与山东莱芜猪、广西陆川猪PID1蛋白氨基酸同源性为98.2%与97.7%;进化树分析结果表明白洗猪与两个猪种间遗传关系相对较远,种间比对黄牛、牦牛、猕猴、小鼠、眼镜王蛇、人、原鸡、非洲爪蟾、大鼠和斑马鱼PID1蛋白氨基酸同源性依次为96.6%、96.6%、96.3%、95.0%、93.9%、91.7%、90.8%、88.2%、69.7%和67.3%;系统进化树分析表明PID1基因在多物种之间的进化高度保守,结构功能分析表明白洗猪PID1基因功能区主要是编码链氨基酸C端的PTB结构域。本研究成功克隆了白洗猪PID1基因,为探究其对白洗猪肌内脂肪沉积方面的影响及为白洗猪种资源开发利用奠定理论基础。

白洗猪种质特性的研究

为了解白洗猪的种质特性，试验采用测定白洗猪生长发育指标、屠宰性能、肉质特性的方法进行研究。结果表明：白洗猪生长高峰期为2～8月龄，4月龄后公猪生长发育性能优于母猪；平均屠宰率为（73．36±5．40）％，平均眼肌面积为（30．98±2．88）cm2，平均背膘厚为（32．66±3．58）mm，平均皮厚为（4．05±0．37）mm，平均腿臀比为（25．58±1．80）％，平均大理石纹评分为（3．42±0．36）分，平均剪切力为（27．00±1．47）N，平均滴水损失为（1．40±0．25）％，平均失水率为（11．04±1．42）％，平均熟肉率为（68．50±3．30）％。试验测定了17种氨基酸，6种必需氨基酸、11种风味氨基酸和2种其他氨基酸，必需氨基酸中组氨酸的平均含量最高为（1．102±0．308）g／kg，风味氨基酸中以脯氨酸的平均含量最高为（1．266±0．432）g／kg。

LYRM1与LYRM2基因在白洗猪及其杜白杂交一代不同组织中的表达研究

为探究LYRM1与LYRM2基因在白洗猪及其杂交一代(杜洛克与白洗猪的杂交一代,DBF1)不同组织中的表达水平,寻找白洗猪和DBF1猪脂肪沉积候选基因。本实验以10月龄白洗猪和DBF1猪为研究对象,采用实时荧光定量PCR法对白洗猪和DBF1猪心、肝、脾、肺、肾、胃、皮下脂肪、背最长肌的2个基因相对表达水平进行检测。结果表明:LYRM1与LYRM2基因在白洗猪和DBF1猪的8个组织中均有表达,且表达趋势趋于一致;LYRM1、LYRM2基因在白洗猪与DBF1猪皮下脂肪组织中高表达,在背最长肌低表达;LYRM1基因在白洗猪皮下脂肪组织中的表达高于DBF1猪,LYRM2基因在白洗猪皮下脂肪组织中的表达量显著高于DBF1猪(P<0.05)。综上所述,推测LYRM1与LYRM2基因可能为白洗猪和DBF1猪脂肪沉积的候选基因。

PID1基因在白洗猪不同组织器官中的表达研究及生物信息学分析

为了探究PID1基因在白洗猪各组织器官中的表达水平及其结构和功能特性,为PID1基因对猪脂肪沉积的作用及其蛋白质特性研究提供理论基础,试验以白洗猪为研究对象,运用实时荧光定量PCR和Nest PCR法分析PID1基因mRNA在白洗猪9个不同组织器官中的表达水平,运用T克隆、蓝白斑筛选等技术克隆PID1基因的CDS区,进一步运用生物信息学软件分析PID1蛋白的生物特性。结果表明：PID1基因mRNA表达量在肝脏中最高,心脏中最低,其表达水平依次为肝脏〉肾脏〉肺脏〉小肠〉胃〉脾脏〉大肠〉肌肉〉心脏;白洗猪PID1基因的克隆CDS区与NCBI上传的序列一致;白洗猪PID1基因编码217个氨基酸,分子质量为24.8 ku,属亲水性蛋白,在PID1蛋白的二级结构中α螺旋比率较大,跨膜区预测分析未发现跨膜区域。

PPARγ与FAS基因在白洗猪及苏白杂交F1代不同组织中的表达分析

为研究PPARγ和FAS基因在白洗猪及其杂交一代(苏太猪与白洗猪的杂交一代,SBF1代)不同组织中的表达规律,本实验采用实时荧光定量PCR技术分析PPARγ基因和FAS基因mRNA在心脏、肝脏、脾脏、肺脏、肾脏、胃、皮下脂肪和背最长肌8个组织器官中的表达水平。结果显示:PPARγ和FAS基因在白洗猪和SBF1代8个组织中均有表达,PPARγ基因在白洗猪和SBF1代皮下脂肪组织中的表达量极显著高于其他组织,且白洗猪的皮下脂肪组织表达量显著高于SBF1代猪;FAS在2个猪种皮下脂肪组织的表达量均极显著高于其他组织,且SBF1代猪的皮下脂肪组织表达量显著高于白洗猪。结果提示,PPARγ与FAS基因可能在白洗猪和SBF1代猪的脂肪沉积中发挥重要作用,推测在白洗猪中PPARγ基因对其脂肪沉积作用更大,在SBF1代猪中FAS作用更显著,可为白洗猪种质资源利用与新品种培育提供参考。

白洗猪不同组织FTO基因的表达研究

为了探究FTO基因在白洗猪不同组织器官中的m RNA差异表达情况,本研究以10月龄贵州白洗猪为研究对象,采用RT-PCR方法对试验猪只9个组织进行试验。结果表明:10月龄白洗猪9个组织中FTO基因m RNA均有表达,且表达量有所差异,总体上说,白洗猪FTO基因m RNA的表达丰度由大到小为脾>肾>心>小肠>肺>肌肉>大肠>肝>胃。表明FTO在10月龄白洗猪中为多组织表达肉质关联基因,可为优质白洗猪的选育提供遗传背景参考。

白洗猪线粒体DNA控制区分子遗传变异分析

对濒临灭绝贵州地方猪种白洗猪线粒体DNA控制区进行分子遗传学研究，为其科学保种和合理开发利用提供科学依据。PCR扩增线粒体DNA控制区全序列，直接测序分析。结果表明：白洗猪线粒体DNA控制区全长1254-1314bp，可以分为3个区；按中间重复区序列是否发生变异可以分为A、B2种类型；聚类分析和单倍型遗传距离分析显示，各类型分布频率很不均衡，遗传多样性呈降低趋势。结果说明，贵州白洗猪可能有2个母系起源，该物种已经濒临灭绝，单倍型多样度较丰富，但是遗传多样性正在逐步丧失，亟需进行科学的保护。

基于博弈论的P2P系统激励机制

针对P2P系统中的白洗问题,提出一种新的激励机制,采用博弈理论分析方法,揭示传统Tit-for-Tat策略在具有白洗用户的P2P系统中进化的不稳定性,指出引入恰当的身份费用改进Tit-for-Tat策略是种遏制白洗攻击的有效方法。仿真实验结果表明,该机制能够有效提升系统整体性能。

Purification and Identification of Antifreeze Proteins in Ammopiptanthus mongolicus

The conventional protein chromatography technique was adopted to purify the antifreeze proteins (AFPs) from the leaves of Ammopiptanthus mongolicus (Maxim.) Cheng f. Two bands on native PAGE gel showed thermal hysteresis activity, one was band B1, whose thermal hysteresis was 0.46 ℃ at 8 g/L, which showed two bands (67 kD, 21 kD) on SDS_PAGE gel; the other was B3, whose thermal hysteresis was 0.45 ℃ at 10 g/L, and it contained only a single protein (39.8 kD). Both B1 and B3 are not glycoproteins, because neither do they interact with Shiff_reagent, nor show ultraviolet characteristics of a typical glycoprotein.

Detection of disseminated pancreatic cells by amplification of cytokeratin-19 with quantitative RT-PCR in blood,bone marrow and peritoneal lavage of pancreatic carcinoma patients

AIM： To evaluate the diagnostic potential of cytokeratin-19 （CK-19） mRNA for the detection of disseminated tumor cells in blood, bone marrow and peritoneal lavage in patients with ductal adenocarcinoma of the pancreas. METHODS： Sixty-eight patients with pancreatic cancer （/7 = 37）, chronic pancreatitis （n = 16）, and non-pancreatic benign surgical diseases （/7 = 15, control group） were included in the study. Venous blood was taken preoperatively, intraoperatively and at postoperative d 1 and 10. Preoperative bone marrow aspirates and peritoneal lavage taken before mobilization of the tumor were analyzed. All samples were evaluated for disseminated tumor cells by CK-19-specific nested-PCR and quantitative fluorogenic RT-PCR. RESULTS： CK-19 mRNA expression was increased in 24 （64%） blood samples and 11 （30%） of the peritoneal lavage samples in the patients with pancreatic cancer. In 15 （40%） of the patients with pancreatic cancer, disseminated tumor cells were detected in venous blood and bone marrow and/or peritoneal lavage. In the peritoneal lavage, the detection rates were correlated with the tumor size and the tumor differentiation. CK-19 levels were increased in pT3/T4 and moderately/poorly differentiated tumors （G2/G3）. Pancreatic cancer patients with at least one CK-19 mRNA-positive sample showed a trend towards shorter survival. Pancreatic cancer patients showed significantly increased detection rates of disseminated tumor cells in blood and peritoneal lavage compared to the controls and the patients with chronic pancreatitis. CONCLUSION： Disseminated tumor cells can be detected in patients with pancreatic ductal adenocarcinorna by CK-19 fluorogenic RT-PCR. In peritoneal lavage, detection rate is correlated with tumor stage and differentiation. In the clinical use, CK-19 is suitable for the distinction between malignant and benign pancreatic disease in combination with other tumor-specific markers.

Acute myelogenous leukemia and acute leukemic appendicitis:A case report

Acute myelogenous leukemia(AML)can involve the gastrointestinal tract but rarely involves the appendix. We report a male patient who had 1 year partial remission from AML and who presented with apparent acute appendicitis as the initial manifestation of leu-kemia relapse.Pathological findings of the appendix revealed transmural infiltrates of myeloblasts,which indicated a diagnosis of leukemia.Unfortunately,the patient died from progression of the disease on the 19th d after admission.Although leukemic cell infiltration of the appendix is uncommon,patients with leu-kemia relapse can present with symptoms mimicking acute appendicitis.

Effect of Raw Material for Distillers Grains Production on Protein Quality for Ruminants

The present experiment was focused on quality of dry distillers＇ grains with solubles （DDGS） produced from corn （DDGSc）, wheat （DDGSw）, triticale （DDGSt）, and wet distillers grains from corn （WDGc） for ruminants. The products were tested for dry matter （DM）, crude protein （CP）, neutral detergent fibre （NDF）, acid detergent fibre （ADF） acid detergent insoluble nitrogen （NIAD）, amino acid （AA） profile, CP degradability and intestinal digestibility （ID） of rumen undegraded protein （RUP）. The average content of CP （g/kg DM） ranged from 289.9 （DDGSc） to 356.9 （DDGSw）. The highest content of essential AA was in WDGc （440.1 g/160g N） followed with DDGSc. The most variable was the content of Lys in DDGSw （from 13.69 to 22.79 g/160 g N）. The NIAD was found the highest for DDGSw （from 16.8% to 36.2%）, effective CP degradability was only 50.2% and ID of RUP 82.2%, total essential AA 81.2%, Lys 77.69% and Met 81.4%. Lys was generally the least digestible AA. The ruminally degradable CP fraction was in the range from 52.6% to 70.2% for DDGSc. ID of total and essential by-pass AA was very high 96.2% and 96.1%, Lysine 90.9% and Methionine 96.7%. From these data it can be concluded that DDGS from grains are a good source of protein for ruminants.

The Effect of Urea Treatment on the Chemical Composition and Rumen Degradability of Sorghum Stover

The objectives of the study were to investigate the effects of different levels of urea treatments on chemical composition, nutritional value and rumen degradability of sorghum stover. Two groups of animals were used in this experiment. The first group, which served as control, was offered untreated sorghum stover. The other, the experiment group recived sorghum stover to which was added 2%, or 4% urea. Crude protein （CP） content of the treated sorghum was enhanced （P 〈 0.05） over the untreated one, and ranked as 7.30% and 6.05% CP for 4% and 2% respectively. Nutrient detergent fiber （NDF） content was decreased （P 〈 0.05） from 92.5% （control） to 89.8% and 87.8% for 2% and 4% urea respectively.Ether extract （EE） content was decreased （P 〈 0.05） from 1.77% （control） to 1.63% and 0.82% for 2% and 4% respectively. The rumen degradability was increased （P 〈 0.05） from 59.2% （control） to 64.2%, and 67.2% for 2%, and 4% sorghum and in hours 0, 4, 8, 16, 24, 48, 72 and 96.

Nutritional Value Evaluation of Saccharum spontaneum L. Germplasm Resources

The contents of dry matter, crude fat, crude protein, neutral detergent fiber, acid detergent fiber, crude ash, Ca and P in 43 Saccharum spontaneum L.germplasms during the vegetative period were determined. Among them, the crude protein, crude fat, neutral detergent fiber, acid detergent fiber, P and Ca contents were treated as the judging indicators. The nutritional value evaluation was carried out with the analytic hierarchy process(AHP). The results showed A49(Guangxi)had the highest nutritional value. Its dry matter, crude protein, crude fat, crude ash,neutral detergent fiber, acid detergent fiber, Ca and P contents were 32.35%,7.20%, 4.06%, 8.07%, 75.81%, 50.72%, 0.23% and 0.16% respectively. While A3(Guangdong) had the lowest nutritional value. Its dry matter, crude protein, crude fat, crude ash, neutral detergent fiber, acid detergent fiber, Ca and P contents were32.24%, 4.62%, 0.51%, 6.38%, 46.40%, 40.02%, 0.15% and 0.09% respectively.The crude protein content differed significantly among different germplasms. A48 had the highest crude protein content(9.11%), and A14 had the lowest crude protein content(3.72%). Based on the evaluation results, the 43 Saccharum spontaneum L.germplasms were divided into 3 groups: high-nutritional value type, moderate-nutritional value type and low-nutritional value type. We hoped to provide a theoretical reference for the application of Saccharum spontaneum L. as a forage grass.

贵州3个地方猪种的mtDNA D-loop序列遗传多样性分析

为了研究3个贵州地方猪种（白洗猪、从江香猪和黔北黑猪）mtDNA D-loop区的遗传多样性,本试验采用PCR直接测序的方法测定了3个贵州地方猪种共57个个体的mtDNA D-loop区全序列.结果表明,3个贵州地方猪种mt DNA D-loop区序列长度为1254 ～1314bp,可分为高变区、串联重复区和保守区,串联重复片段有4种,可分为A型和B型;D-loop区的碱基含量特点为A＋T明显高于G＋C;在白洗猪、从江香猪和黔北黑猪的高变区分别检测到6、6、8个均为转换的突变位点,分别定义了4、4、6种单倍型,单倍型多样度（Hd）为0.6386～ 0.8974,核苷酸多样度为0.0025 ～0.0035,3个贵州地方猪种均表现出较为丰富的遗传多样性.

Alteration of surfactant proteins A and D in bronchoalveolar lavage fluid of pneumocystis carinii pneumonia

Objective To understand the interaction between surfactant proteins and pneumocystis carinii pneumonia (PCP),and the impact of corticosteriods on surfactant proteins.Methods We established rat models of PCP and bacterial pneumonia induced by subcutaneous injection of 25mg cortisone acetate.At 8- 12 wk,the bronchoalveolar lavage fluid(BALF)of rats was collected.Total nucleated cells of BALF were counted and differentiated,and the concentrations of surfactant protein A(SP-A)and surfactant protein D(SP-D)were measured by immunoblotting assay.The rats were divided into three immunosuppressive groups and a normal control group.Group I,normal control(n = 6),consisted of healthy SD rats;group Ⅱ,negative control(n = 6),consisted of rats with cortisone acetate injection for over 8 wk without lung infection;group Ⅲ,bacterial pneumonia(n = 11),rats were injected with cortisone acetate over 8 wk that resulted in bacterial pneumonia without other pathogens isolated;and group Ⅳ,PCP(n = 14),rats with injected cortisone acetate for 8 - 12 wk and developed PCP without other pathogens isolated.Results Our results indicated that the total cell count in BALF in the negative control group was lower than that in the normal control group(P ＜ 0.001).During PCP infection,the total cell count and the percentage of polymorphonuclearcytes(PMNs)in BALF were significantly increased(P ＜ 0.01),but were lower than those in the bacterial pneumonia group.The concentration of SP-A of BALF in PCP(45.1 ± 22.1 μg/ml)was significantly increased in comparison with that in the negative control(16.2 ± 9.9 μg/ml,P ＜ 0.05)and bacterial pneumonia groups(6.2 ± 5.6 μg/ml,P ＜ 0.001).We also found that the relative content of SP-D was significantly higher in PCP(24249 ±4780 grey values)than that in the negative control (13 384 ± 2887 grey values,P ＜ 0.001)and that in bacterial pneumonia(11 989 ± 2750 grey values,P＜0.001).SP-A and SP-D were also higher in the moderate to heavy group of PCP than those seen in the mild group(P ＜ 0.01,P ＜ 0.001).SP-A and SP-D were higher in the negative control group than those in the normal control group,but there was no significant difference between the 2 groups.Conclusion These results suggest that the concentrations of SP-A and SP-D in BALF are increased by pneumocystis carinii specific stimulation,but the alteration is not related to the corticosteriod usage.

Structural analysis of a nanoparticle containing a lipid bilayer used for detergent-free extraction of membrane proteins

In the past few years there has been a growth in the use of nanoparticles for stabilizing lipid membranes that contain embedded proteins. These bionanoparticles provide a solution to the challenging problem of membrane protein isolation by maintaining a lipid bilayer essential to protein integrity and activity. We have previously described the use of an amphipathic polymer （poly（styrene-co-maleic add）, SMA） to produce discoidal nanoparticles with a lipid bilayer core containing the embedded protein. However the structure of the nanoparticle itself has not yet been determined. This leaves a major gap in understanding how the SMA stabilizes the encapsulated bilayer and how the bilayer relates physically and structurally to an unencapsulated lipid bilayer. In this paper we address this issue by describing the structure of the SMA lipid particle （SMALP） using data from small angle neutron scattering （SANS）, electron microscopy （EM）, attenuated total reflection Fourier transform infrared spectroscopy （ATR-FTIR）, differential scanning calorimetry （DSC） and nuclear magnetic resonance spectroscopy （NMR）. We show that the particle is disc shaped containing a polymer ＂bracelet＂ encircling the lipid bilayer. The structure and orientation of the individual components within the bilayer and polymer are determined showing that styrene moieties within SMA intercalate between the lipid acyl chains. The dimensions of the encapsulated bilayer are also determined and match those measured for a natural membrane. Taken together, the description of the structure of the SMALP forms the foundation for future development and applications of SMALPs in membrane protein production and analysis.

Effect of Long-term Experimental Warming on the Nutritional Quality of Alpine Meadows in the Northern Tibet

The nutritional quality of grasslands is closely related to recruitment of young and population dynamics of livestock and wild herbivores. However, the response of nutritional quality to climate warming has not been fully understood in the alpine meadow on the Tibetan Plateau, especially in the Northern Tibet. Here, we investigated the effect of experimental warming(beginning in 2008) on nutritional quality in three alpine meadows(site A: 4313 m, B: 4513 m and C: 4693 m) in the Northern Tibet. Crude protein(CP), neutral detergent fiber(NDF), acid detergent fiber(ADF), crude ash(Ash), ether extract(EE) and water-soluble carbohydrate(WSC) were examined in 2018–2019. Experimental warming only increased the content of CP by 27.25%, ADF by 89.93% and NDF by 41.20%, but it decreased the content of Ash by 57.76% in 2019 at site B. The contents of CP and WSC both increased with soil moisture(SM). The content of CP decreased with vapor pressure deficit(VPD). The combined effect of SM and VPD was greater than air temperature(Ta) in controlling the variations of the CP content, ADF content and nutritional quality. Compared to Ta, VPD explained more of the variation in NDF and Ash content. All of these findings suggest that warming effects on nutritional quality may vary with site and year, and water availability may have a stronger effect on the nutritional quality than temperature in the alpine meadow of the Northern Tibet.