[目的]对体成熟和老龄关中奶山羊睾丸进行代谢组学分析,探究关中奶山羊睾丸衰老代谢规律,为睾丸衰老症提供代谢标志物.[方法]根据关中奶山羊年龄、体质量和精液质量,选择体成熟(24月龄,C组)和老龄(60月龄,T组)关中奶山羊公羊各6只,采集双侧睾丸组织样本,使用液相色谱串联质谱(LC-MS/MS)方法对睾丸组织代谢物进行检测分析,利用多维和单维相结合的统计方法对2组不同代谢物进行检测、对比与鉴别,通过富集差异代谢物筛选关中奶山羊睾丸发育和衰老代谢中的潜在关键通路.[结果]LC-MS/MS检测到2组关中奶山羊睾丸中有129种差异代谢物,与T组相比,C组有74种代谢物显著上调,55种显著下调;对前35个差异代谢物进行比较鉴定发现,21个显著上调,14个显著下调.通过对不同代谢产物的富集和分析,获得了 9条潜在的关键代谢途径,即铁死亡、ABC转运蛋白、谷胱甘肽代谢、精氨酸生物合成、氨基酸糖和核苷酸糖代谢、胆碱在肿瘤中的代谢、精氨酸和脯氨酸代谢、嘌呤代谢及牛磺酸和亚牛磺酸代谢.[结论]筛选出了与关中奶山羊睾丸发育和衰老相关的129种差异代谢物,鉴定了前35种差异代谢物,获得了 9条潜在的关键代谢通路.

[目的]探究不同泌乳阶段的山羊乳与牛乳中核苷酸物质含量的差异性,为功能羊乳产品的差异化利用提供科学依据.[方法]采集山羊和奶牛泌乳初期不同时间(2,7,15 d),泌乳盛期不同时间(30,50,100 d)和泌乳末期(200 d)的奶样,采用快速溶剂萃取技术处理后再采用高效液相色谱串联质谱(LC-MS/MS)法,精确测定次黄嘌呤、尿苷、黄嘌呤、羟基嘌呤、腺嘌呤核苷酸、次黄嘌呤核苷酸、尿嘧啶核苷酸、胞嘧啶核苷酸和鸟嘌呤核苷酸等9种核苷酸物质的含量.[结果]次黄嘌呤、尿苷、黄嘌呤、羟基嘌呤、腺嘌呤核苷酸、次黄嘌呤核苷酸、尿嘧啶核苷酸、胞嘧啶核苷酸和鸟嘌呤核苷酸等9种核苷酸物质在整个试验期山羊乳中均检出;腺嘌呤核苷酸、尿嘧啶核苷酸、次黄嘌呤核苷酸仅在泌乳初期2～15 d牛乳中检出,鸟嘌呤核苷酸在泌乳2～100 d牛乳中检出,次黄嘌呤在整个试验期牛乳中均未检出,其他4种核苷酸物质(黄嘌呤、羟基嘌呤、胞嘧啶核苷酸和尿苷)在整个试验期牛乳中均检出.除次黄嘌呤和牛乳中的羟基嘌呤外,牛乳和羊乳中的其他核苷酸物质含量均随泌乳时间的延长总体呈下降趋势.山羊乳中腺嘌呤核苷酸、尿嘧啶核苷酸、次黄嘌呤核苷酸、胞嘧啶核苷酸、鸟嘌呤核苷酸、尿苷和黄嘌呤含量显著或极显著高于牛乳;山羊乳中羟基嘌呤含量在泌乳2～15 d显著高于牛乳(P＜0.05),在泌乳30～200 d极显著低于牛乳(P＜0.01).[结论]不同泌乳阶段山羊乳与牛乳中核苷酸物质含量存在明显差异,这可能与山羊与奶牛的泌乳方式不同有关.

[目的]探究苜蓿干草与燕麦干草的组合效应对关中奶山羊采食量、瘤胃发酵参数、产奶量、乳品质的影响,为合理利用苜蓿干草和燕麦干草资源提高关中奶山羊的生产性能提供支持.[方法]选取体况相近的泌乳中期关中奶山羊240只,随机分为对照组及T1、T2和T3组,每组3个重复,每个重复20只羊.对照组饲喂50％配方精料十 50％苜蓿干草,T1组饲喂50％配方精料+25％苜蓿干草+25％燕麦干草(m(苜蓿)∶m(燕麦)=1∶1),T2组饲喂50％配方精料+30％苜蓿干草+20％燕麦干草(m(苜蓿)∶m(燕麦)=3∶2),T3组饲喂50％配方精料+37.5％苜蓿干草+12.5％燕麦干草(m(苜蓿)∶m(燕麦)=3∶1),进行75 d的饲喂试验.期间进行采食量、产奶量、瘤胃发酵参数(pH,NH3-N、乙酸、丙酸、异丁酸、丁酸、异戊酸、戊酸、总挥发性脂肪酸含量及乙酸/丙酸)、乳成分(乳蛋白、乳脂肪、乳糖、全乳固体含量及脂蛋比)数据的采集及测定.[结果]与对照组相比,T3组奶山羊的日干物质采食量和产奶量显著提高(P＜0.05).4个处理组奶山羊瘤胃液的pH差异不显著,T1和T3组奶山羊瘤胃液的NH3-N显著高于对照组和T2组(P＜0.05).T1、T2和T3组奶山羊瘤胃液的乙酸、丙酸、戊酸、乙酸/丙酸和总挥发性脂肪酸含量显著高于对照组(P＜0.05);T3组的乳脂肪、全乳固体含量和脂蛋比显著高于其他3组(P＜0.05).T3组和对照组乳蛋白含量显著高于T1和T2组(P＜0.05),4组奶山羊瘤胃液乳糖含量差异不显著(P＞0.05).[结论]苜蓿干草与燕麦干草以质量比3∶1比例组合,可以提高关中奶山羊的消化性能和生产性能,改善奶山羊乳品质.

为了研究FSH和二氢吡啶以及二者联合使用对关中奶山羊精液品质、精子形态变化的影响,选择年龄、膘情、体重相近的成年关中奶山羊公羊36只,随机分为4组,每组3个重复,每个重复3只羊.对照组公羊饲喂基础日粮,试验1组在基础日粮中添加二氢吡啶(剂量为每日每头50mg),试验2组采用减量注射FSH(第1天40U/只,第2天20U/只,第3天10U/只),试验3组同时使用二氢吡啶和FSH,对关中奶山羊射精量、密度、精子活力及精子的形态变化进行测定.结果表明,关中奶山羊公羊使用FSH与二氢吡啶对提高精子活力和射精量效果极显著(P<0.01),试验1组、试验2组及试验3组精子密度显著高于对照组(P<0.05),二者联用极显著提高了鲜精与冻精活力,降低精子畸形率;单纯使用FSH的试验2组与对照组间在第6周后精子活力差异不显著(P>0.05).

[目的]试验旨在从代谢组学角度探究关中奶山羊睾丸发育代谢机制.[方法]选择1月龄断奶雄性关中奶山羊和24月龄体成熟的雄性关中奶山羊各6只,采集睾丸组织,使用液相色谱-质谱(LC-MS)技术对睾丸组织进行化学检测,通过多维和单维分析相结合的方式对两组不同代谢物进行化学检测、对比与鉴别,通过富集差异代谢物分析筛选关中奶山羊发育代谢中的潜在关键通路.[结果]在1和24月龄关中奶山羊睾丸组织中共筛选出334个差异代谢物,其中显著上调137个,显著下调197个.对前36个差异代谢物进行比较鉴定发现,分别为脂质和类脂质分子、有机酸及其衍生物、未分类化合物和苯丙烷和聚酮化合物四大类.经相关性分析发现,在1和24月龄关中奶山羊睾丸发育过程中,脂质和类脂质分子与甘油磷脂呈最大正相关,羧基及其衍生物与甘油磷脂呈最大负相关.对不同的代谢物进行富集分析,筛选出7条潜在的重要代谢通路,分别为肿瘤中的胆碱代谢、精氨酸和脯氨酸代谢、肿瘤中的中心碳代谢、铁死亡、谷胱甘肽代谢、氨酰-tRNA生物组成以及牛磺酸和亚牛磺酸代谢.[结论]本试验从代谢组学角度揭示了 1和24月龄关中奶山羊睾丸的差异代谢物及代谢机制,为今后哺乳动物睾丸的发育研究奠定了基础.

Goat milk is an integral part of china' s milk industry, in order to explore the protein group differences of guanzhong dairy goats in different lactation periods. In this study, TMT technology was used to analyze the differences between the colostrum group and mature milk histone group of Guanzhong dairy goats. The credible proteins were analyzed and identified by PCA and univariate analysis. Combined with the screening conditions of differential proteins: Fold change > 1.2 and P-value<0.05, the differential proteins were obtained. Enrichment analysis of differential proteins was performed using GO and KEGG databases. The results showed that a total of 241 differential proteins were screened out in colostrum and mature milk, of which 80 proteins were significantly up-regulated and 161 proteins were significantly down-regulated. Differentially expressed proteins are mainly enriched in Acute-phase response, Lactose biosynthetic process, Ro Protein Signal Transfer, Extracellular region, Extracellular space, Golgi apparatus, GTPase activity and GTP binding. The KEGG pathway enrichment analysis showed that the most significantly different proteins were enriched in the Ras signaling pathway, chemokine signaling pathway, complement pathway, Rap1 signaling pathway, and PPAR signaling pathway. Our results showed that goat colostrum showed more metabolic pathways related to immune diseases and mature milk showed more pathways related to cancer, which promoted the study of protein polymorphism in goat milk and It provides a theoretical basis for further study on the nutritional value of goat milk in different lactation periods.

[目的]探讨了不同pH值、渗透压的稀释液对关中奶山羊冻精品质的影响,以确定关中奶山羊精液最佳保存与冷冻效果.[方法]通过显微检测在不同pH值、渗透压的稀释液处理对降温前、平衡后与解冻后的精子的活率、复苏率、精子顶体完整率、精子畸形率及精子冻后存活时间等指标进行评估.[结果]关中奶山羊精液稀释液pH值为7.3时,降温前、平衡后与解冻后的精子活率最高,分别达到(0.742±0.011)％,(0.645±0.011)％,(0.489±0.012)％;冻后活率、复苏率及解冻后顶体完整率分别达到(0.431±0.009)％,(63.1±0.427)％,(65.7±2.018)％;精子存活时间在降温前、平衡后及解冻后分别达到(12.50±0.141)h,(11.96±0.186)h,(11.61±0.753)h,冻后8 h活率为(0.52±0.014)％;当渗透压为△0.754℃时,其精子的保护效果最佳,降温前、平衡后与解冻后的精子活率分别达到(0.752±0.045)％,(0.671±0.024)％,(0.649±0.036)％;冻后活率、复苏率及解冻后顶体完整率分别达到(0.481±0.019)％,(63.6±0.377)％,(69.9±1.068)％;精子存活时间在降温前、平衡后及解冻后分别达到(11.82±0.165)h,(11.94±0.145)h,(11.70±0.753)h,冻后8 h活率达到(0.43±0.033)％.[结论]关中奶山羊精液稀释液最合适的pH值是7.3,最佳渗透压为△0.754℃,这一结果对奶山羊稀释液配方优化提供了一定的理论指导.

[Objective] Using the Internet of things, cloud computing, big data, and artificial intelligence technology to improve the intelligent and precise breeding technology of large-scale dairy goat farms and accelerate the genetic progress and improvement effect of dairy goats are important trends in the development of intelligent animal husbandry. [Method] The system uses C programming technology, Java programming technology, Internet of things information technology, and data fusion technology to make the best pairing combination according to the individual physiological information, behavior information, individual phenotype, pedigree analysis, genome data, proteome data and metabolome data of dairy goats, and develops an intelligent and accurate breeding system for large-scale dairy goat farms. [Result] Including web server and smart phone client, by setting the "intelligent mode" to realize the intelligent adjustment of the goat farm environment and breeding matching. [Conclusion] The intelligent control of the equipment can be realized without manual intervention, so as to accelerate the genetic progress and breeding effect, which will be quickly promoted and applied in the field of modern dairy goat breeding.

为了探究萨能奶山羊细管冻精最适冷冻程序,本试验设置5个不同的冷冻程序[在5～-10℃温区内,各组降温速率相同(6℃/min),在-10～-140℃危险温区内设置5个不同梯度的降温速率(25℃/min,35℃/min,40℃/min,55℃/min,65℃/min)]用于程序化冷冻中.试验利用全自动细管精液程控冷冻仪编制冷冻程序,通过casa系统测定精液在不同冷冻程序下精子活力变化,同时利用特异性荧光探针(异硫氰酸镧-花生凝集素,FITC-PNA)检测解冻后精子顶体完整率,用低渗精子肿胀法(HOST)检测解冻后精子质膜完整率.结果表明,冷冻程序C组(5～-10℃,降温速率6℃/min;-10～-140℃,降温速率40℃/min)解冻后精子活力、质膜完整率和顶体完整率最高,分别达到60.75％、38.10％和71.01％,均显著高于其他组(P<0.05).在危险温区内,降温速率为40℃/min可以较好地保证冷冻萨能奶山羊精子的活力和质膜功能,同时利用程序化冷冻程序C组可显著提高精子的受精能力,C组的降温速率可以提高冷冻萨能奶山羊解冻后精液质量.

为了研究不同组合的水煮大豆与干炒大豆对关中奶山羊产奶性能、瘤胃发酵参数的影响.试验选用泌乳期关中奶山羊240只,分为4组,每组3个重复,每个重复20只羊,预试期15 d,正试期75 d;对照组饲喂85％基础日粮+15％干炒大豆作为饲料,试验1组饲喂85％基础日粮+6％水煮大豆+9％干炒大豆作为饲料,试验2组饲喂85％基础日粮+9％水煮大豆+6％干炒大豆作为饲料,试验3组饲喂85％基础日粮+15％水煮大豆作为饲料.结果表明:与对照组相比,在日粮中添加9％水煮大豆+6％干炒大豆可以显著提高关中奶山羊产奶量(P<0.05),能够有效提升乳成分中的乳蛋白含量.同时,经过处理的水煮大豆,能够有效调节瘤胃内环境稳定性.研究表明,日粮中添加水煮大豆可提高奶山羊产奶量,改善乳品质,调节瘤胃内环境.

Purpose: To assess Chinese residents’ dietary exposure to aflatoxin B1(AFB1) from corn-based foods and corresponding health risk.Methods: Dietary intake of aflatoxin B1from corn-based foods in different population groups was simulated by Monte Carlo simulation and Bootstrap sampling,and health risk associated with AFB1 intake was evaluated by applying a quantitative cancer potency formula developed by Joint FAO/WHO Expert Committee on Food Additives.Results: Simulated AFB1 intake(90% confidence interval) from corn-based foods in different population groups of high corn consumption,2-6-year-old children,standard adults,urban standard adults and rural standard adults was 29.98(19.03-68.59),10.18(6.46-23.30),5.46(3.47-12.49) ng/(kg.d) and 13.37(8.49-30.60) ng/(kg.d) at the 99th percentile,respectively;and the evaluated cancer risk was 0.924(0.587-2.114),0.314(0.199-0.718),0.168(0.107-0.385) cancers/(105persons.a) and 0.412(0.262-0.943) cancers/(105persons.a).Conclusion: The health risk associated with AFB1in corn-based foods in China is relatively low.

Studies regarding plant phosphorus accumulation and utilization efficiency can provide scientific basis for reasonable application of phosphate.Dynamics of phosphorus content of winter wheat and utilization efficiency of winter wheat was conducted based on the long-term positional fertilization experiment on dry highland of the Loess Plateau.The results show that the phosphorus contents of winter wheat plants with application of phosphate fertilizer presented a V shape curve.Phosphorus contents of winter wheat were high during the early growth period,and decreased with the crop growth,and reached the minimum in the filling stage,and then rebounded in the last stage.Phosphorus of winter wheat accumulated mainly in two stages,i.e.,stage of jointing—flowering and stage of filling—mature.Sufficient supply of phosphorus in these two stages could ensure better growth of winter wheat.In terms of phosphorus utilization efficiency,yield and other indicators,phosphate application should be controlled in a reasonable range between 45～90 kg/hm2 in the scenario of nitrogen application 90 kg/hm2.

The study on soil particle composition and enrichment of available phosphorus was conducted with a long-term fertilization field experiment and laboratory analysis methods.The results showed the smaller soil particle was,the higher the proportion of soil particles was in four fertilization treatments,but the different fertilizer treatments would influence the proportion of the same particle size.The combined application of nitrogen fertilizer,organic fertilizer on the basis of a single P application(NP、PM、NPM),would help to increase the 0.25 mm proportion of particles,the NPM was the most obvious.The long-term application of organic fertilizer could improve available phosphorus in soil particles,in same time the proportion of the water-soluble phosphorus in available phosphorus of the soil particles may be increased.Available phosphorus in the soil(including Olsen-P,water-soluble phosphorus) mainly enriched in the 2 mm soil particles,the highest enrichment rate of available phosphorus was in 0.25 mm soil particles.The combined application of nitrogen and phosphorus fertilizer(NP) or nitrogen,phosphorus and organic fertilizer(NPM) could significantly improve enrichment rate of available phosphorus in 0.25 mm soil particles,but the application of phosphorus and organic fertilizer(PM) could increase enrichment rate of available phosphorus in 0.25~2 mm soil particles.

Cucumber angular leaf spot is an important disease in cucumber production in Shaanxi.The incidence of cucumber caused by Pseudomonas syringae was over 50%.Through tissue plating and Koch's pustule methods,one pathogen was isolated from diseased cucumber plant in Yangling of Shaanxi province.The pathogen was identified as Pseudomonas syringe strain CP001 based on morphological characteristics,cultural physiological and chemical characteristics,and the sequence of 16S ribosomal DNA.Biological characteristics of strain CP001 had been preliminarily studied.Results showed that optimal pH was 6-8,and temperature was 22-29 ℃.

The impact of fertilization on water use efficiency(WUE) of winter wheat on dry-land of Loess Plateau was researched through observing the factors about water use efficiency under different fertilization treatments.The results show that increasing nitrogen application decreased the leaf WUE in prior period of growing periods but increased it in later period and increased the LAI of wheat.There was no obvious impacts on leaf WUE and LAI by increasing the phosphate fertilizer.Increasing nitrogen application significantly increased WUE in level of biomass and yield by increasing biomass and field of wheat and more phosphate fertilizer application increased the biomass and yield but was no significant impacts on WUE in level of biomass and yield.Correlation analysis between biomass,yield,LAI and WUE were significantly correlated because of increasing the LAI of wheat by fertilizing and then increasing the photosynthetic efficiency of population and accumulation of dry matter and increasing the WUE finally.

With the aid of Licor-6400 portable photosynthesis system,the physiological indexes and relate denvironmental factors were measured and influence of environmental factors on photosynthetic physiologic indexes and leaf water use efficiency of winter wheat was studied on dryland of Loess Plateau.The results howed that diurnal fluctuation of physiological rate(Pn)of leaf was a not obvious two-hump curve and that oftranspiration rate(Tr)was a typical resupinate"U".the Pn and Tr in a.m.were distinctly higher than in p.m.,but the time at which the maxium appeared was different in different growth stage.The time of maxium appeared of Tr and Pn was same in elongation stage and the time of maxium appeared of Tr was later than that of Pn in grain filling stage.The effects of environmental factors on physiologic indexes in elongation stage was more obvious than that in grain filling stage.The most important environmental factors on Pn and Tr were photosynthetic active radiation(PAR)and CO2 concentration.The influence of Temperature(T)and relative humidity(RH)on stomatal conductance(Gs) was progressively increased and the influence on Intercellular CO2 concentration was obvious.The diurnal fluctuation of water use efficiency was a not obvious two-hump curve and the time of maxium appeared was earlier than those of Pn and Tr.The daily mean WUE in filling stage was lower than that in elongation stage to 30.5%.The correlations among Pn,Tr and Gs reached 1% significant level and there was a significant negative correlation between temperature of leaf and Gs.