对咸阳市畜禽粪便污染环境问题的初探

对咸阳地区的畜禽养殖状况,畜禽粪便的污染程度,畜禽粪便治理的现状与存在的问题,提出了治理的措施及治理后的前景,以期为政府部门在研究制定咸阳市规范时提供考虑。     

杜仲叶影响绵羊血清代谢组学的研究

为探索杜仲叶（Eucommia ulmoides leaves,EUL）对绵羊营养代谢和生理功能的影响,本研究选取25~30 kg、70~80日龄的湖羊30只,随机分为3组,每组10只,分别为对照组（无杜仲叶日粮组,CTL）、低剂量添加组（10%杜仲叶日粮组,EUL1）、高剂量添加组（20%杜仲叶日粮组,EUL2）。预试期15 d,正试期90 d。试验结束时,通过静脉采血,离心后分别取血浆和血清,血浆用于生化分析,血清用于代谢组学分析。结果显示,饲喂杜仲叶后,EUL1和EUL2组绵羊血浆中葡萄糖、非酯化脂肪酸、高密度脂蛋白和极低密度脂蛋白均升高,EUL2组与CTL组差异显著或极显著（P<0.05;P<0.01）,EUL1组与CTL组差异不显著（P>0.05）;EUL1和EUL2组尿素较CTL组极显著降低（P<0.01）,总胆固醇水平显著降低（P<0.05）,EUL1和EUL2组间差异不显著（P>0.05）。血清样品采用液相色谱-质谱联用仪（LC-MS）进行检测,在正模式下得到593个代谢物,在负模式下得到1 570个代谢物。通过主成分分析（PCA）、偏最小二乘判别分析（PLS-DA）及正交偏最小二乘判别分析（OPLS-DA）发现,各试验组间的差异代谢物较多,能将其得分图明显区分。进一步对变量重要性因子大于1.0（VIP>1.0）的代谢物进行t检验后发现,各组之间有24种特征代谢物差异显著（P<0.05）。这些差异代谢物涉及体内葡萄糖、脂肪酸和氨基酸等的代谢,有的代谢物还与动物的免疫机能相关。杜仲叶饲料对绵羊的营养代谢、生理状态和免疫状况可产生明显的影响,代谢组学可有针对性地分析代谢物发生的步骤及生理作用,为阐明杜仲叶影响营养代谢的机制提供参考。     

四种常用草坪草的水分蒸散与补偿规律的研究

通过调控灌水量,采用蒸散仪法对南京地区四种常用的草坪草的水分蒸散和水分补偿规律进行了研究.研究结果表明,(1)在正常供水条件下,冷地型草坪草(凌志高羊茅、匍匐剪股颖) 的蒸散量普遍高于暖地型草坪草(普通狗牙根、日本结缕草)的蒸散量;在限量供水条件下,蒸散量受土壤水分条件的限制;(2) 温度、水气压的变化与草坪草的蒸散量呈显著的正相关,大气因子对草坪草的蒸散具有显著的影响;不同留茬高度对草坪草的蒸散具有显著的影响,一般在留茬4cm时蒸散量最低.合理的水分补偿应结合气象因子与修剪高度进行;(3)在8～10月,四种草坪草的补水量为凌志高羊茅8.9～216.5mm,匍匐剪股颖79～158.2mm,普通狗牙根116.0mm,日本结缕草107.4mm;(4)草坪草具较大的节水空间,只要灌溉合理就可以避免耗水过多问题.     

秸秆还田与施氮对水稻根系分泌物及氮素利用的影响研究

秸秆还田及适宜的施氮水平,对于提高资源的利用效率及减少环境污染有着重要的意义,本研究以徐稻3号为材料,在盆栽条件下设置3种氮肥水平与2种秸秆处理,研究了秸秆与氮肥处理下水稻根际分泌特性的差异及其与养分吸收利用的关系。结果表明,在同一秸秆处理下,中氮(NN)增加结实期氮素的累积,提高氮(N)素的吸收利用率,同时,NN处理下根系分泌物中苹果酸、琥珀酸、有机酸总量、氨基酸的含量及根系活性上升。在同一氮肥处理下,秸秆还田提高N素吸收累积,增加根系分泌物中苹果酸、琥珀酸及草酸的含量,降低柠檬酸的含量,根系分泌物中有机酸总量、氨基酸含量及根系活性在秸秆还田后明显上升。相关分析表明,结实期根系分泌物中有机酸总量、苹果酸、琥珀酸、氨基酸的含量以及根系活性与氮素累积量及氮素吸收利用率呈显著或极显著的正相关。     

基于体外细胞模型的霉菌毒素毒性评价

霉菌毒素是由多种真菌产生的次级代谢产物,广泛存在于食品和饲料中。霉菌毒素污染的粮食和饲料会给畜牧业生产和畜产品质量安全带来极大隐患。研究霉菌毒素致毒机理,为今后研究其对动物及人的影响开展更深入更全面的研究提供理论依据。细胞模型作为一种常用的体外试验方法广泛用于毒理学研究中。本文简述了黄曲霉毒素B_1(AFB_1)、赭曲霉毒素A(OTA)、脱氧雪腐镰刀菌烯醇(DON)、玉米赤霉烯酮(ZEA)和展青霉素(PAT)的一般特性,并综述了利用细胞模型进行AFB_1、OTA、DON、ZEA和PAT毒性、联合毒性及致毒机理研究的进展。     

饲粮中添加不同生物制剂对杜寒杂交肉羊生产性能和屠宰性能的影响

本试验旨在比较饲粮添加不同生物制剂对杜寒杂交肉羊生产性能、屠宰性能、组织器官发育及肉品质的影响。采用单因素试验设计,选取平均体重约为32 kg的杜寒杂交F1代肉羊160只,随机分为5组,每组4个重复,每个重复8只。对照组采用基础饲粮,试验组分别添加21 mg/kg莫能菌素、4×109CFU/kg地衣芽孢杆菌、3.2×109CFU/kg酿酒酵母菌、1.1 g/kg复合生物制剂(地衣芽孢杆菌≥6×109CFU/g、酿酒酵母菌≥4×109CFU/g、碱性蛋白酶≥1 000 U/g)。预试期10 d,正试期56 d,每2 d记录1次采食量,每20 d进行1次称重,当复合生物制剂组羊只的平均体重达到约50 kg时,每组选取10只羊进行屠宰,测定其屠宰性能、组织器官重量和肉品质指标。结果表明:1)复合生物制剂组平均日增重、屠宰率显著高于对照组(P0.05);地衣芽孢杆菌组和复合生物制剂组料重比显著低于对照组(P0.05)。2)地衣芽孢杆菌组、酿酒酵母菌组、复合生物制剂组复胃重量均显著高于对照组(P0.05),复合生物制剂组复胃重量占宰前活重比例显著高于对照组和莫能菌素组(P0.05);地衣芽孢杆菌组、酿酒酵母菌组、复合生物制剂组小肠重量及其占宰前活重比例均显著高于对照组、莫能菌素组(P0.05)。3)酿酒酵母菌组肾脏重量占宰前活重比例显著高于对照组(P0.05),其他内脏器官重量占宰前活重比例在各组间无显著差异(P0.05)。4)各组肉品质指标差异不显著(P0.05)。综合得出,从作为饲料添加剂对肉羊生产性能作用效果来看,地衣芽孢杆菌、酿酒酵母菌、复合生物制剂可以替代莫能菌素,地衣芽孢杆菌好于酿酒酵母菌,复合生物制剂最佳。     

Amplification,Sequence Analysis and Tissue Expression Detection of FUT2 Gene Coding Regions of Dongchuan Pigs

Porcine alpha (1,2) fucosyltransferase (FUT2) gene was importance in glycosphingolipid biosynthesis-globo series, potentially played a regulatory role during Escherichia coli (E. coli) F18 infection process in weaned piglets. In order to explore sequence structure of porcine FUT2 gene and its biological function, this test amplified FUT2 gene CDS sequence of Dongchuan pigs by PCR, forecasted and analyzed the protein sequences and functional regions of FUT2 gene, its expression level was detected in 11 tissues of 8 Dongchuan weaned piglets in 35 days old at the meantime. The results showed that the CDS sequence of FUT2 gene was 1 023 bp, which encoded 340 amino acids. FUT2 protein was fat-soluble hydrophilic protein, which the structure was not stable, including a transmembrane helix structure, but without signal peptide that suggested the FUT2 protein was a membrane protein;FUT2 protein included 2 N-glycosylation sites (No. 185 and No. 305 amino acids), without O-glycosylation sites, there were 14 potential phosphorylation sites, included 6 Ser, 2 Thr and 6 Tyr, analyzing the functional regions found that the FUT2 protein had a superfamily of conserved domains:FUT1-FUT2-like (58-319 amino acids). The phylogenetic tree result showed that the relative relationship between swine and cattle was relatively close, but was distant from chimpanzee, human, mouse and rat. FUT2 gene was expressed in all 11 tissues of Dongchuan weaned piglets, there were higher expression in digestive tract and immune tissues. The present results suggested that FUT2 gene might play a role to resistance to E. coli F18 in weaned piglets, and might indirectly against E. coli F18 through the synthesis of fucosyltransferase.     

Establishment of a Duplex Real-time RT-PCR Assay for the Differential Detection of Nipha Virus and Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus

To establish a rapid,sensitive and specific assay for the differential detection of Nipah virus (NiV) and highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV),a duplex Real-time RT-PCR was developed with specific primers and probes targeting to the special sequences of NiV M gene and HP-PRRSV nsp2 gene by optimization of reaction conditions.The performance of the assay was linear ranging from 4.6×10¹ to 4.6×10⁷ copies/μL for RNA standard control of NiV M (NiV-M-RNA) and from 4.1×10¹ to 4.1×10⁸ copies/μL for RNA standard control of HP-PRRSV nsp2 (HP-PRRSV-nsp2-RNA),and detection limits of the assay was 46 copies for the NiV-M-RNA and 4.1 copies for the HP-PRRSV-nsp2-RNA,respectively.The coefficients of variation (CVs) of both inter-assay and intra-assay repeatability were less than 2.0%,showing good repeatability.The assay was able to specifically detect NiV and HP-PRRSV simultaneously without cross-reaction with classical swine fever virus (CSFV),porcine epidemic diarrhea virus (PEDV),swine influenza virus (SIV),porcine parvovirus (PPV),pseudorabies virus (PRV) and porcine circovirus type 2 (PCV2).Of the 236 samples from pigs for both NiV and HP-PRRSV detection by the established assay,all the samples were negative for NiV,8 samples were HP-PRRSV positive.In conclusion,this assay offers a useful approach for the differential detection of NiV and HP-PRRSV in clinical specimens from the pigs.     

Biological Functions of TLRs in Mammalian Ovulation Processes

Toll-like receptors (TLRs) is the main category of pattern recognition receptors.It is not only expressed in classical immune cells,but also expressed in the ovary and the genital tract of a variety of mammals.It plays an important role in ovarian activities.Biological functions of TLRs in the ovulation processes is the main research content in the field of reproductive immunology because that ovulation is a core event in ovarian activities and the key to determine the success or failure of reproductive.This review will concentrate on expression and distribution of TLRs in mammalian ovary,regulation mechanisms of TLRs expression and function,and the functions and significance of the ovulation process.Then we analyze briefly its possible functions in ovulation-related diseases.We want to provide a reference in research areas of reproductive immunology.     

Study on the Change Rule of Egg Yolk Antibody in Laying Hens after First Immunization by Japanese Encephalitis Virus

The purpose of this experiment was to study the immunization rule of the egg yolk antibody affected by different vaccines,immunization dose and injection ways and further to discuss the optimal immunization procedures of the laying hens for the preparation of egg yolk antibody against swine Japanese encephalitis virus.180 brown laying hens without any vaccines were selected and divided into 18 groups randomly,each group of 10 hens.Groups 1,2 were the control groups,injected with the sterile saline;Groups 3 to 10 were injected with subcutaneous or intramuscular injection,and the vaccine was injected with 0.2,0.5,1.0 and 1.5 mL successively.Groups 11 to 18 were also adopted two kinds of injection,followed by the same dose of vaccine immunization.Six eggs of each experimental group were gathered before immune day and after 3,7,10,14,18,21 and 28 days,the egg yolk antibody was extracted and the titer was determined.As a result,the egg yolk antibody titers of groups 1 to 6,11 and 12 were all 0,and no significant immune response produced;The hens from 7 to 10 groups were injected with the inactivated vaccine.After 7 days,the average antibody titer reached the peak,and the duration of the antibody was 14 days.The hens from 13 to 18 groups were injected with the attenuated virus vaccine.After 14 days,the average antibody titer reached the highest value,and the duration of the antibody was 21 days.The egg yolk antibody titers were not significantly different in the two compared experiment groups with the same injection dose but with different injection ways (P>0.05).With the same injection way of each experiment group,and the difference was significant (P>0.05).Compared with some groups with the same injection and vaccine,the titer of yolk antibody was gradually increased with the increase of the immune dose,and the difference was significant (P<0.05).The results showed that,no matter intramuscular or subcutaneous injection,in order to produce a significant immune response to hens,the immune antigen dose was 1.0 mL inactivated vaccine or 0.5 mL attenuated vaccine at least.Compared with the attenuated and inactivated vaccine,inactivated vaccine stimulated the body to produce the antibody faster,but the maintenance time was shorter;The lower dose of attenuated vaccine could stimulate the body to produce antibodies,but the speed was slower,the maintenance time was longer.