农药酶免疫分析技术研究进展

自从酶免疫分析原理提出后，近30年来已获得了巨大的进步，成为农药分析的一个非常重要的方法。本文对农药酶免疫分析技术的原理和测定程序进行了评述．并总结了近年酶免疫分析在农药领域研究中的应用，最后，对农药酶免疫分析技术存在的问题和发展趋势作了讨论。     

Gly-Gly肽和Gly-L-Leu肽在蛋鸡肠道内水解的研究

采用蛋鸡离体外翻肠段培养法,将小肠分为十二指肠、空肠前段、中段、后段和回肠五个部位肠段,洗净外翻。2种二肽培养液(Gly-Gly肽和Gly-L-Leu肽溶液)作为两组对照培养液,每种二肽培养液中添加肽酶抑制剂(Bestatin和Amastatin),作为试验培养液,39.5℃培养25min,每5min取样一次,测定培养液中的二肽含量。结果表明,培养5min后,含Gly-Gly肽的对照和试验培养液中均未能检测到完整Gly-Gly肽。而含Gly-L-Leu肽的对照培养液Gly-L-Leu肽的含量降低到16.75％,试验培养液则下降到43.40％。而试验培养液中Gly-L-Leu肽的含量10min后无显著降低(P>0.05)。各培养时段试验培养液Gly-L-Leu含量均显著高于对照培养液(P<0.05)。由此认为,离体肠囊在培养过程中能够迅速释放肠肽酶及一些生物活性物质,快速水解2种二肽。肽酶抑制剂(Bestatin和Amastatin)能抑制Gly-L-Leu的水解,但不能抑制Gly-Gly的水解。     

Impact of cold-season grazing and supplementary feeding on rumen metabolic parameters and micro-organisms in the ewes of Gansu Alpine Fine Wool Sheep北大核心CSCD

An experiment was conducted to scientifically identify the appropriate feed for Gansu Alpine Fine Wool ewes in order to change the animals' breeding mode, which currently can only be mated at the age of 2.5 years due to insufficient nutritional supply. The experiment selected 48 12-month-old ewes and randomly divided them into group a (Diet 1), group b (Diet 2), group c (Diet 3), and a control group with no supplementary feeding. The feed test was run for 90 days. The rumen pH of groups a and b were very significantly higher (P<0.01) or group c significantly lower (P<0.05) than control group. The rumen ammonia nitrogen, protein nitrogen and total nitrogen of groups a, b and c were all higher than control group (P<0.01). The total volatile fatty acids of group a and b were all higher than the control group (P<0.01), group b significantly higher than group c (P<0.05). The molar ratio of acetic acid and propionic acid in group a was very significantly higher than control group (P<0.01), group b and c were significantly higher than control group (P<0.05). The molar ratio of butyric acid in group a was very significantly higher than group c (P<0.01). The ratio of acetic acid and propionic acid in group b was significantly lower than control group (P<0.05). The number of several rumen fiber-degrading bacteria and protozoa in groups a, b and c were very significantly (P<0.01) or significantly (P<0.05) higher than the control. In conclusion, this study shows that supplementary feeding can positively affect the rumen metabolic parameters and the number of several rumen microorganisms in Gansu Alpine Fine Wool ewes. In general, the effects of Diet 1 were the strongest, while Diet 2 also produced notable improvements. © 2018, Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

活化铁尾砂与镁改性生物炭配施对水稻幼苗生长及盐碱土性质的影响

为探究活化的高硅型铁尾砂与镁改性生物炭配施材料对水稻幼苗生长及盐碱土壤理化性质的影响以及改善盐碱地水稻生产力的可行性,本研究应用电子扫描显微镜对生物炭材料进行形貌结构观察,应用傅里叶变换红外光谱仪对生物炭材料进行官能团表征;开展盆栽实验,探究活化铁尾砂与生物炭材料配施对水稻幼苗的形态学和生理学的影响及对盐碱土的改善效果。结果表明,相比于其他生物炭材料,活化铁尾砂-镁改性生物炭材料孔隙较大,表面更加粗糙,对于养分的吸附能力强,表面的官能团丰富。盆栽实验中活化铁尾砂-镁改性生物炭配施组中水稻幼苗株高、根长、根冠比和干质量分别较对照组提高12.61%、191.49%、42.93%和100.00%;叶片的丙二醛和活性氧含量分别降低65.76%和46.46%;过氧化氢酶、超氧化物歧化酶、叶绿素和可溶性蛋白值分别升高117.35%、44.75%、55.00%和19.31%。施用活化铁尾砂-镁改性生物炭材料后,盐碱土的电导率降低,p H、总碳、总氮、土壤有效硅、总磷和总钾含量升高。研究证明活化铁尾砂-镁改性生物炭材料性能优越,并且活化铁尾砂与镁改性生物炭配施改善了盐碱土壤理化性质和养分含量,使水稻幼...     

微塑料对双酚A在鲤鱼肠道中累积及生长生理的影响

探明微塑料（MPs）对双酚A （BPA）在鱼类肠道中累积特征及鱼类生长生理的影响,本研究以黄河鲤鱼为模型生物,分析了0.5 μm聚苯乙烯微塑料（PS-MPs）与BPA联合作用下鲤鱼肠道中微塑料及BPA的累积特征、鲤鱼生长及其抗氧化酶活性,以及它们之间的响应关系。结果表明：联合处理下鲤鱼肠道中的PS-MPs含量随时间呈线性增加,且随投加的微塑料浓度增加而增加,而PS-MPs累积速率随时间呈先增加后减小趋势,其中在BPA+PS（L）处理（1 mg·L^-1 BPA+20 μg·L^-1 PS-MPs）下,0.25 d时鲤鱼肠道中PS-MPs累积速率达到峰值（373.81 μg·g^-1·d^-1）,BPA+PS（H）处理（1 mg·L^-1 BPA+100 μg·L^-1 PS-MPs）下,则是在0.125 d达到最高（644.00 μg·g^-1·d^-1）。与单一BPA暴露相比,联合暴露下鲤鱼肠道中BPA累积量增加,与BPA （1 mg·L^-1 BPA）处理相比,BPA+PS （L）和BPA+PS （H）处理下鲤鱼肠道中BPA含量分别提高了6.13%和9.74%,BPA累积速率分别增加了190.01%、373.80%。相较于对照处理,BPA处理和MPs与BPA联合处理均引起鲤鱼肠组织中超氧化物歧化酶（SOD）活性、过氧化氢酶（CAT）活性、还原型谷胱甘肽（GSH）含量、丙二醛（MDA）含量增加,使体质量下降幅度减缓,其中BPA、BPA+PS （L）和BPA+PS （H）处理下鲤鱼体质量（21 d）较对照处理分别下降1.22%、3.90%、4.33%。当微塑料投加量达到100 μg·mL^-1时,联合处理会增加鲤鱼肠道中SOD活性、CAT活性和GSH含量,抑制MDA产生,从而缓解MPs和BPA联合作用对鲤鱼造成的氧化损伤,并且减缓鲤鱼体质量下降。研究表明,微塑料的存在会增加双酚A在鲤鱼肠道中的累积,且两者联合作用对鲤鱼产生了协同毒理效应,导致鲤鱼生长速率减缓,体质量下降。     

镉胁迫对凡纳滨对虾血细胞基因表达的影响

为探讨镉(Cd)胁迫下凡纳滨对虾(Litopenaeus vannamei)血细胞的分子响应,以不同浓度的Cd2+(0,0.5 mg/L和5 mg/L)进行胁迫,于不同胁迫时间取血淋巴,测定血细胞中Trx 2、Grx 2、Grx 3和MGST 3的基因表达量变化.结果显示,Trx 2、Grx 3和MGST 3表达量在胁...     

The effects of creep feed composition and form and nursery diet complexity on small intestinal morphology and jejunal mucosa-specific enzyme activities after weaning in pigs

Fifty-six litters from first-parity sows standardized to 12 piglets were used to determine the effects of creep feed composition and form and the provision of low- or high-complexity nursery diets on the evolution of small intestinal histomorphology and jejunal mucosa-specific enzyme activities postweaning. At 5 d of age, litters (initial bodyweight [BW] 2.31 ± 0.61 kg) were assigned to one of four creep feeding regimens (n = 14): 1) commercial creep feed (COM), 2) liquid milk replacer (LMR), 3) pelleted milk replacer (PMR), or 4) no creep feed (NO). At weaning (21 d of age), six pigs per litter were provided a HIGH- (contained highly digestible animal proteins) or LOW- (contained corn and soybean meal as main protein sources) complexity nursery diet (n = 7). At 21, 28, and 59 d of age, two pigs per pen (one castrated male and one female) were euthanized, and ileal and jejunal segments for histomorphological measurements and jejunal mucosal scrapings were collected to determine specific mucosa enzyme activities. At weaning, pigs provided COM had a greater ileal absorptive capacity (M) than LMR or NO, which were not different (14.1 vs. 10.4 and 10.5 ± 0.9 μm²; P < 0.05); PMR was intermediate. On days 28 and 59, M was not different among pigs regardless of creep feed treatments. Pigs fed LOW had reduced jejunal villus height (VH; P < 0.001) and M (P < 0.001) on day 28 vs. day 21. The VH and M were not different for pigs fed HIGH or LOW by the end of the nursery period. For all dietary treatments except COM-HIGH and COM-LOW, jejunal mucosal maltase-specific activity was not different between days 21 and 28 of age but greater on day 59 (P < 0.05). For pigs that received COM-HIGH, maltase-specific activity was not different between days 21 and 28 but greater on day 59 than day 28 (P < 0.05). For pigs that received COM-LOW, maltase-specific activity was not different between days 21, 28, and 59. Regardless of creep or nursery treatment, sucrase-specific activity was the greatest on day 59, followed by days 21 and 28 (P < 0.001), and lactase-specific activity was greater on day 21 than on days 28 and 59 (P < 0.001), which were not different. Therefore, pigs that provided LOW diet had greater villus atrophy and reduced M during the first week after weaning vs. pigs that provided HIGH, regardless of creep feeding regimen, but were able to recover by the end of the nursery period.     

棕榈粕替代部分玉米对藏羊母羊小肠形态发育、消化酶活性及抗氧化功能的影响

试验旨在探究精料补充料中使用不同比例棕榈粕替代玉米对藏羊母羊肠道组织形态学、消化酶活性、pH、脂多糖以及抗氧化能力的影响。选取初始体重相近且健康的2～3月龄高原型藏羊母羊120只,随机分为4组,每组30只,每组6个重复,每个重复5只母羊,分别饲喂0%、15%、18%和21%水平的棕榈粕替代精料中玉米。试验期97d。结果显示：1)0%组与15%组间小肠各段的绒毛高度、绒毛宽度、隐窝深度、黏膜厚度以及绒毛高度/隐窝深度差异均不显著（P>0.05）;2)0%组空肠的α-淀粉酶、纤维素酶、脂肪酶及糜蛋白酶显著或极显著小于15%组（P<0.05或P<0.01）;3)0%组空肠的谷胱甘肽过氧化物酶、过氧化氢酶活性显著低于15%组与18%组（P<0.05）,相较于21%组差异不显著（P>0.05）;4)18%组与21%组空肠的脂多糖含量显著或极显著高于0%组（P<0.05或P<0.01）,与15%组相比差异不显著（P>0.05）。由此可见,棕榈粕可替代部分玉米饲喂藏羊母羊,推荐替代玉米的比例为15%。     

在循环养殖系统中不同溶氧量对虹鳟幼鱼代谢水平的影响

在循环养殖系统中设置四种溶氧水平,分别为7.05、8.82、11.84和15.80 mg/L,其中8.82 mg/L为对照组,对虹鳟幼鱼（体长13.0-18.5 cm）的代谢水平及生长率进行了研究。结果表明,饲养30 d后7.05mg/L的低溶氧使虹鳟幼鱼耗氧率和排氨率下降,11.84和15.80 mg/L溶氧下饲养的鱼耗氧率明显增加,15.80 mg/L使鱼的排氨率显著高于对照组。并且11.84和15.80 mg/L组虹鳟幼鱼在24 h内都具有高的代谢水平。随着溶氧量提高,虹鳟幼鱼的增重率、特定生长率和饲料转化率均随之升高,表现出生长指标的明显变化。