细胞因子的检测及其在鸡免疫抑制病中的应用

细胞因子的检测方法分免疫学检测法、分子生物学检测法和生物学活性检测法。感染鸡的多种病毒引起的免疫抑制与细胞因子的分泌水平和表达异常有关。因此,对细胞因子的检测为鸡病毒性免疫抑制病的发病机理和防制方法的研究提供了重要依据。     

非洲猪瘟背景下猪群的高效养殖

非洲猪瘟自2018年8月份发生以来,对我国养猪业的影响非常巨大。很多科研人员和畜牧工作者为非洲猪瘟的防控进行建言献策,对猪场防控非洲猪瘟带来了很大的帮助。文章就非洲猪瘟背景下猪群的健康、免疫及母猪繁殖进行综述,为生猪产业的复产提供帮助,实现猪场养殖效益的最大化。     

鸡新城疫病毒强毒Q-BS株的分离与鉴定

从2003年10月至2004年6月,在河北、辽宁、山东等地区鸡群中大规模发生以神经症状、肠道出血为主的流行性疾病。本文对从河北省某AA肉鸡场的病死鸡中分离的病毒毒株,经过实验室的系统鉴定,证实该分离株具有血凝性,且可被ND标准阳性血清所抑制和中和,不能被AI(H5亚型与H9亚型)标准阳性血清及阴性血清抑制;该分离株的毒价为109.3ELD50/0.1ml,MDT为57.6h,ICPI为1.89,IVPI为2.62,回归试验鸡的临床表现与自然病例基本一致。试验结果证明,该毒株属于嗜神经型新城疫病毒强毒株,并命名为Q-BS株。     

姜曲海母猪发情周期性腺激素及其子宫受体含量的变化规律

以长白猪为对照,测定了姜曲海母猪发情周期血浆中雌二醇和孕酮及其子宫受体含量。发现发情期血浆雌二醇的峰值为58.3±3.9pg/ml,与长白猪比差异不显著。间情期孕酮的最高水平和平均水平均比长白猪高(23.25±1.36对14.28±1.42ng/ml和18.56±1.42对11.76±0.57ng/ml,P<0.01)。发情期和间情期的细胞质雌二醇受体(CER)分别为 410±30.3和367±14.2fmol/mgDNA,其kd值分别为4.8±0.65和4.0±0.8nmol;细胞核雌二醇受体(NER)分别为1390±195.3和620±28.9fmol/mgDNA,其kd值为6.6±2.1和4.4±1.3nmol;细胞质孕酮受体(CPR)分别为364±56.0和147±46.0 fmol/mgDNA;细胞核孕酮受体(NPR)分别为337±51.8和184±67.0fmol/mgDNA。发情期和间情期子宫NER含量较长白猪高(P<0.05),说明此时姜曲海母猪子宫对雌二醇具有较高的敏感性。     

Apoptosis‐Like Events and In Vitro Fertilization Capacity of Sex‐Sorted Bovine Sperm

This study utilized three staining assays (Annexin V, mitochondrial membrane potential (JC‐1) and TUNEL) for flow cytometric analysis of apoptosis in sex‐sorted sperm from four different bulls (A, B, C and D). Correlations between sperm quality and IVF efficiency were then assessed to determine which assay provided the best prediction of IVF efficiency. The results of the Annexin V assays, as well as measures of viable sperm, early apoptosis, necrotic sperm and mitochondrial membrane potential (?ψm) showed that the sex‐sorted sperm collected from bull A significantly differed from those of the other three bulls (p < 0.05). In addition, the levels of DNA fragmentation in sex‐sorted sperm from bull A were significantly lower than those from bulls B and C (p < 0.05). The percentage of cells reaching the cleavage and blastocyst stages in sex‐sorted sperm from bull A were significantly greater than those from the other bulls (p < 0.05). A significant positive correlation was observed between viable sperm and the percentage of cells at the cleavage or blastocyst stages (p < 0.05). In contrast, a negative correlation was found between early apoptotic sperm and the percentage of cells at the cleavage or blastocyst stages (p < 0.05). In conclusion, these results indicated that the Annexin V assay was the most reliable technique for the prediction of the IVF success of sex‐sorted bovine sperm.     

母猪饲粮添加甜菜碱对巴马香猪哺乳仔猪血液指标的影响

本试验旨在研究母猪饲粮添加甜菜碱对巴马香猪哺乳仔猪血液指标的影响。选取3~7胎次妊娠巴马香猪40头,随机分为2组,每组20头,单栏饲养。对照组饲喂基础饲粮,试验组在基础饲粮中添加3.5 kg/t甜菜碱。试验期为母猪配种后第3天至分娩后第21天。试验结束时,从每组随机选取10窝仔猪,每窝选取1头仔猪采血,测定血浆激素含量、抗氧化指标和游离氨基酸含量。结果表明:与对照组相比,甜菜碱组哺乳仔猪血浆胆囊收缩素(CCK)、酪酪肽(PYY)、瘦素(LEP)、丙二醛(MDA)、过氧化氢(H2 O2)和丙氨酸(Ala)含量显著降低(P<0.05),血浆鹅肌肽(Ans)、1-甲基组氨酸(1⁃MeHis)和3-甲基组氨酸(3⁃MeHis)含量显著升高(P<0.05),血浆苏氨酸(Thr)(P=0.069)、谷氨酸(Glu)(P=0.055)和肌肽(Car)(P=0.055)含量呈下降趋势,血浆亮氨酸(Leu)含量呈升高趋势(P=0.069)。综上所述,母猪饲粮添加甜菜碱可降低哺乳仔猪血浆摄食相关因子水平,减弱机体的氧化水平,改变血浆游离氨基酸含量,有利于仔猪的生长发育与机体健康。     

辽宁省大连市羊群布鲁氏菌病横断面研究

本研究采用横断面研究方法,通过两个阶段的随机抽样检测,结合问卷调查,获得大连市羊群布鲁氏菌病血清流行率及感染风险因素,初步了解了当地养羊场户对布鲁氏菌病防控相关知识的掌握情况和行为实践特点。研究结果表明,大连市羊布鲁氏菌病场群血清流行率为8.89%(95%CI:6.14%~11.63%)。从饲养模式看,调查的6个种羊场均无布鲁氏菌病感染,而商品代饲养场和散养村羊群布鲁氏菌病血清流行率分别为13.33%(95%CI:5.64%~21.03%)和8.21%(95%CI:5.24%~11.17%),差异不显著(X~2=1.93,p=0.170.05)。从饲养品种看,不同品种羊群之间的布鲁氏菌病血清流行率差异也不显著(X~2=0.15,p=0.930.05)。单因素分析结果表明,"与其他养羊场户共用种公羊""产后胎衣丢弃和喂狗""流产物喂狗""与其他养羊场户共用交通工具""近一年羊贩子进羊圈""近一年在交易市场买卖羊"等行为是羊群感染布鲁氏菌病的风险因素,而"购入前检测布鲁氏疾病"是显著的保护性因素。进一步的logistic回归分析表明,"近一年在交易市场买卖羊"(OR=4.91,95%CI:1.57%~15.35%)"流产物处理不当"(OR=1.87,95%CI:1.06%~3.30%)是主要的羊群布鲁氏菌病感染风险因素。"知信行"调查结果表明,大连市养羊从业者对布鲁氏菌病的认知程度较好,说明兽医部门的宣传工作有成效。但从行为实践角度来看,仍有部分养羊场户存有侥幸心理,在日常养殖和生活中不采取降低布鲁氏菌病感染风险的措施。     

2016——2018年我国部分猪群塞尼卡病毒回顾性监测

塞尼卡病毒(Senecavirus A,SVA)是最近新出现的可引起猪水泡样病变的单股小RNA病毒。为了解SVA的流行状况,采集对2016—2018年从我国辽宁等省份猪群的164份病料和2018年从我国福建等7省份35个屠宰场的458份组织混合样品和95份血清样品,用荧光实时定量RT-PCR方法进行SVA检测和分析。结果显示:在2016年的48份样品中,从3个省份检测出7份阳性样品,阳性率为14.6%。2017年的32份病料中,从5个省份检测出7份阳性样品,占比为21.9%;2018年的84份病料中,从3个省份检测出19份阳性样品,占比为22.6%。屠宰场组织样品中,从6个省份检出55份SVA阳性样品,阳性率为12.0%;血清样品中,从1个省份检出7份阳性样品,阳性率为7.4%。结果表明,我国猪群SVA感染年份至少可追溯到2016年;SVA在我国流行面相对较广,且猪群中存在隐性带毒,因此须重视猪群的SVA监视和监测。     

Sarcocystis sinensis is an ultrastructurally distinct parasite of water buffalo that can cause foodborne illness but cannot complete its life-cycle in human beings

In this study, we compared the morphology of Sarcocystis sinensis and Sarcocystis hominis, and assessed the infectiousness of S. sinensis for human volunteers. The cysts of S. sinensis were from water buffalo (Bubalus bubalis) and those of S. hominis were from cattle (Bos taurus). Transmission electron microscopy of S. sinensis cysts revealed that the cyst wall had leaning, finger-like protrusions measuring 1.44-5.08 μm in length and without invaginations on the tip surface of the protrusions. In contrast, the cyst wall of S. hominis had upright, finger-like protrusions measuring 9.43 μm×2.42 μm and with vesicle-like invaginations on the tip surface of the protrusions. Scanning electron microscopy revealed that surface of the protrusions was arranged as rectangles in S. sinensis, as compared to tongue-shaped in S. hominis. Other distinguishing features of S. sinensis include a thin ground substrate (GS) zone with microtubules and small, circle-like structures located at the base of the protrusions. Human volunteers, after consuming S. sinensis cysts, produced no sporocysts or oocysts in feces, suggesting that humans could not serve as definitive hosts for S. sinensis. By contrast, many sporocysts and oocysts were passed in feces of a human volunteer 11-29 days after ingestion of S. hominis cysts. These results showed that S. sinensis and S. hominis are separate species and S. sinensis cannot use human being as the definitive host.     

气相色谱法测定禽蛋中有机氯农药和多氯联苯残留量

建立了同时测定禽蛋中14种有机氯农药(OCPs)和7种多氯联苯(PCBs)的气相色谱法。样品用乙腈超声提取,浓硫酸净化,气相色谱法测定,外标法定量。21种待测化合物在5～200μg/L时线性关系良好,方法定量限为0.3～0.7μg/kg,在5、20、100μg/kg三个加标水平下,鸡蛋空白样品的平均加标回收率为75.1%～103.8%,相对标准偏差为1.41%～6.64%。本法简便、快速、准确、成本低廉,适用于禽蛋中多种有机氯农药和多氯联苯的快速筛查。