樱桃谷肉鸭呋喃唑酮中毒的诊治

本文记述了临床上常见的一起樱桃谷肉鸭呋喃唑酮中毒及诊治过程,意在提醒养殖户不要盲目用药,造成不必要的损失,同时给出了家禽呋喃唑酮中毒的治疗措施及合理用药剂量,以期对生产实践有一定的指导意义。     

HPLC同时测定烤肉中的丙烯酰胺和杂环胺

建立了高效液相色谱法同时测定烤肉中丙烯酰胺和杂环胺的新方法.选择适宜的样品前处理方法提取和净化样品,经TSK-gel ODS-80TM柱分离并以配备二极管阵列和紫外检测器的HPLC对丙烯酰胺和杂环胺进行测定.结果表明,该方法的线性范围为0.02-32.0μg/mL,检出限为0.2-0.4ng/g;回收率为67.3％-9...     

Effects of ultrasound-assisted thawing on lamb meat quality and oxidative stability during refrigerated storage using non-targeted metabolomics

The aim of this study was to evaluate the changes of ultrasound-assisted thawing on lamb meat quality and differential metabolite profiles during refrigerated storage. Compared with flow water thawing (FW), pH, a*, C*, and sulfhydryl content of lamb were significantly increased, while L*, drip loss and cooking loss were significantly decreased after ultrasound-assisted thawing (UT). On day 1 (UT1 and FW1) and day 7 (UT7 and FW7) in the UT and FW groups, principal component analysis explained 42.22% and 39.25% of the total variance. In this study, 44 (UT1 and FW1) and 47 (UT7 and FW7) differentially expressed metabolites were identified, including amino acids, carbohydrates and their conjugates, nucleic acids, carbonyl compounds and others. The results of this study provide data to clarify the differences between UT and FW, and lay a foundation for the application of ultrasound-assisted thawing in the meat industry.     

Development of a Liquid Chromatography/Amperometric Detection Method for the Determination of Multiresidue Sulfonamide Antibiotics in Meat‐Based Baby Foods

Sulfonamides were oxidized at a polycrystalline gold electrode in neutral buffered phosphate medium at pH 7 and the electrochemical behavior was investigated using cyclic voltammetry technique. A liquid chromatography methodology based on the C₁₈ reverse phase for the simultaneous separation of nine sulfamides, was studied and optimized. The amperometric detector using a polycrystalline gold substrate as working electrode and operating under pulsed amperometric detection mode (PAD) was tested for the determination of the selected molecules. Under optimal chromatographic and amperometric conditions, the limit of detection of the investigated sulfamides are comprised between 1 µM and 0.05 µM and the dynamic linear range spanned generally over three orders of magnitude. A liquid extraction procedure based on the use of acetonitrile solvent was tested and proposed for the quantitative extraction of sulfonamides from homogenized meat samples. The analytical method was successful tested for the determination of sulfonamides in homogenized meat‐based baby foods with reproducibility and recovery levels ranged between 5.0 % and 7.6 %. and 86 %–106 %, respectively.     

畜禽肉化学成分近红外光谱检测技术研究进展

和传统的肉品化学成分检测方法相比,近红外光谱分析是一种能够快速、简单、安全和可同时测定多种化学成分的肉品检测方法。论述了近年来猪、鸡、牛、羊四种动物肉中粗蛋白质、肌间脂肪、脂肪酸、水分、灰分、肌红蛋白和胶原蛋白七种化学成分的近红外光谱分析检测研究进展,并探讨了目前研究中存在的问题及其原因。从已发表的研究结果可以看出,近红外光谱分析具有替代耗时成本高的现有肉品化学检测方法的巨大潜力,特别是用于商业上同步检测多种化学成分。研究大多采用主成分分析法进行特征光谱筛选,偏最小二乘和修正偏最小二乘法建立校正模型,交互验证进行预测结果评价。目前研究热点集中在肉中脂肪酸含量预测模型和应用近红外高光谱图像和多元回归预测肉中化学成分。近红外光谱预测结果差异性较大,这与样品集选择、光谱预处理和建模方法都有很密切的关系。样品选择对近红外预测精度具有重要的意义,非均质肉样影响了近红外化学成分预测精度。总的来说,肌间脂肪、脂肪酸与水分指标预测效果较好,粗蛋白质和肌红蛋白指标预测效果次之,灰分和胶原蛋白指标预测结果较差。     

Determination of benzenic and halogenated volatile organic compounds in animal-derived food products by one-dimensional and comprehensive two-dimensional gas chromatography–mass spectrometry

Animal-derived products are particularly vulnerable to contamination by volatile organic compounds (VOCs). These lipophilic substances, which are generated by an increasing number of sources, are easily transferred to the atmosphere, water, soil, and plants. They are ingested by livestock and become trapped in the fat fraction of edible animal tissues. The aim of this work was to determine the occurrence, risk for human health and entryways of benzenic and halogenated VOCs (BHVOCs) in meat products, milks and sea foods using gas chromatography– mass spectrometry (GC–MS) techniques. In the first part, the occurrence and levels of the BHVOCs in animal products were studied. One muscle and three fat tissues were analysed by GC–Quad/MS in 16 lambs. Of 52 BHVOCs identified, 46 were found in the three fat tissues and 29 in all four tissues, confirming that VOCs are widely disseminated in the body. Twenty-six BHVOCs were quantified in fat tissues, and risk for consumer health was assessed for six of these compounds regulated by the US Environmental Protection Agency (EPA). The BHVOC content was found to be consistent with previous reports and was below the maximum contaminant levels set by the EPA. In the second part, the performance of GC×GC–TOF/MS for comprehensively detecting BHVOCs and showing their entryways in animal-derived food chains was assessed. Meat, milk and oysters were analysed by GC–Quad/MS and GC×GC–TOF/MS. For all these products, at least a 7-fold increase in the contaminants detected was achieved with the GC×GC–TOF/MS technique. The results showed that the production surroundings, through animal feeding or geographical location, were key determinants of BHVOC composition in the animal products.     

流动注射在线吸附预富集-火焰原子吸收光谱法测定鸵鸟肉中的微量硒

以香烟过滤嘴为微柱吸附材料,建立了流动注射(FI)在线预富集-火焰原子吸收光谱法(FAAS)联用技术测定鸵鸟肉中微量硒。在最佳的仪器工作条件下,硒的增敏因子为4.7,检出限为0.0017μg/mL,相关系数r为0.9987。方法用于鸵鸟肉中微量硒的测定,RSD=2.47%,加标平均回收率99%—101%。     

狗脑抗吗啡镇痛肽“60a”的分离纯化及部分一级结构

本实验室从正常狗脑中又分离获得一个暂称这为“６０ａ”的肽。冻干粉经ＳｅｐｈａｄｅｒＧ－５０和羧甲基纤维素ＣＭ２２柱层析，再经反相高效液相层析纯化得最后样品，经ＳＤＳ电泳和等电聚焦电泳鉴定均为一条带，分子量约８０００，等电点在ｐＨ７．８左右；Ｎ－末端氨基酸为Ｍｅｔ；自Ｎ－末端的部分氨基酸序列为：Ｈ２Ｎ－Ｎｅｔ－Ｌｅｕ－Ｓｅｒ－Ｐｒｏ－Ａｌｓ－Ａｓｐ－Ｌｅｕ－Ｔｈｒ－Ａｓｐ－Ｉｌｅ－Ｌｅｕ－Ｐｈｅ－Ｔ     

德国牧羊犬产仔后的母性行为

本文观测德国牧羊犬三只母犬与其２４只幼仔之间的行为变化规律。记录分析母犬纸饰幼仔、清理巢区、哺乳、对幼仔求乞的拒绝、诱导与训练幼仔的物品嬉戏、格斗嬉戏、挖掘嬉戏以及标记等行为。着重指出母性行为的时间分配、舐饰及清理巢区的生态生物学意义。     

犬冠状动脉周期性血流减少时冠状窦内血浆TXB_2及6-K-PGF_(1α)升高的意义

目的：观察冠状动脉（冠脉）发生周期性血流减少（ＣＦＲｓ）时血栓烷Ａ２（ＴＸＡ２）及前列环素（ＰＧＩ２）的变化及意义。方法：犬剖胸分离出２～３ｃｍ长的冠脉前降支（ＬＡＤ）,用血管钳钳夹方法损伤冠脉内膜后放置血管缩窄环,使冠脉达临界狭窄。缩窄环近端置电磁流量计,诱发ＣＦＲｓ,在ＣＦＲｓ出现前及ＣＦＲｓ出现后４０ｍｉｎ冠状窦内采血,用放免法测ＴＸＡ２及ＰＧＩ２的代谢产物ＴＸＢ２及６－Ｋ－ＰＧＦ１α。结果：ＣＦＲｓ出现４０ｍｉｎ后,ＴＸＢ２及６－Ｋ－ＰＧＦ１α均显著升高（Ｐ＜０．０１）（ＴＸＢ２从７５．６２±４８．８７ｎｇ／Ｌ升至１０９．２２±４５．９９ｎｇ／Ｌ;６－Ｋ－ＰＧＦ１α从１６．１４±９．２８ｎｇ／Ｌ升至３５．５７±１７．２１ｎｇ／Ｌ）。结论：发生ＣＦＲｓ时,血管内皮细胞分泌的６－Ｋ－ＰＧＦ１α随血小板分泌的ＴＸＢ２一同显著升高,其机理可能是血管内皮细胞的一种应激性反应。