乳酸菌发酵法检测牛乳中抗生素残留

目的建立一种简单、准确的检测牛乳中抗生素残留的方法-乳酸菌发酵法。方法以接种量和温度为变量,优化发酵条件;以青霉素为目标抗生素,建立检测方法;以发酵4 h未凝乳的样品中抗生素最低浓度为检测限,测定本方法对20种抗生素的检测限;对比本方法和GB/T 4789.27方法检测111个商品乳样品中抗生素残留检出率,验证本方法的准确性。结果建立了乳酸菌发酵法检测乳中抗生素残留的具体方法;确定了本方法对8类20种抗生素的检测限,其中4类12种抗生素的检测限低于其在牛乳中的最大残留限量(MRL);本方法和GB/T 4789.27方法检测111个商品乳样品抗生素残留检出率分别为9.0%和11.7%。结论本方法操作简单,结果准确,适合企业及基层检测单位作为初筛方法检测牛乳中的抗生素残留。     

微生物法检测乳中抗生素残留及假阳性产生的原因

介绍了乳中抗生素残留检测的常用微生物法氯化三苯四氮唑法、纸片法、活性试验法、试剂盒方法,并从乳本身因素、外来因素2个角度分析实际检测过程中引起假阳性结果的原因,为乳中抗生素检测提供理论参考。     

酶联免疫法与乳及乳制品中抗生素残留的检测

对酶联免疫检测技术(ELISA)做了介绍,并对该技术在乳及乳制品抗生素残留检测的应用进行了评述.阐述了该项技术在乳及乳制品抗生素残留检测中的应用前景.     

国标TTC法与AOAC纸片法检测乳中β-内酰胺类抗生素残留对比研究

对乳中抗生素残留的两种微生物检测法进行了比较,确定2种标准方法对6种广谱β-内酰胺类抗生素的检测限,同时指出国标TTC法在检测灵敏度方面的缺陷.建议乳中抗生素残留检测过程中,采用特异性与灵敏度高、经济简便、检测限达到MRLS规定的AOAC纸片法作为国标TTC检测法的补充.     

免疫分析技术在乳及乳制品抗生素类兽药残留检测中的应用

为了预防与治疗乳牛疾病,抗生素类兽药被广泛应用于乳牛的饲养过程中。而滥用抗生素导致牛奶中抗生素残留超出最大允许残留量,不仅会对牛奶品质造成影响,而且可能会危害到牛奶饮用者的身体健康。因此,如何快速、准确地检测乳与乳制品中抗生素类兽药残留是乳品检测行业和企业亟需解决的问题。本文主要介绍了牛乳中兽药残留的来源、危害及其现状,阐述了酶联免疫分析技术、胶体金免疫层析技术的检测原理及其在应用过程中所具有的不同特点,最后对2种方法的优势与不足进行简要总结,并对免疫分析法在乳与乳制品抗生素类兽药残留检测中的应用前景做出展望。     

乳与乳制品抗生素残留及其在病牛乳中持续时间的探讨

1986年6～7月对南京、无锡、苏州、常州、徐州、淮阴、泰州、盐城等市的10个乳牛场使用抗生素的情况和乳与乳制品中抗生素残留量及其持续时间进行了探讨。結果:各乳牛场均使用青霉素、链霉素等抗生素药物治疗乳牛的各种疾病。应用TTC法检测乳与乳制品中抗生素残留量的检出率时,生奶3.6%,消毒牛奶11.48％、奶粉39.58％;青链霉素水剂在常量下不论给药途径如何,奶中残留持续时间都不超过48小时。病侧乳室灌注抗生素后,在邻室分泌出的乳中不存在抗生素残留;肌肉注射抗生素,奶中残留经24小时就呈阴性,而乳室灌注法奶中的残留要经48小时才转阴性,因此提倡肌注法给药。     

牛乳中β-内酰胺类抗生素残留检测方法的对比研究

对乳中抗生素残留的2种微生物检测法进行了比较,确定2种方法对6种广谱-β内酰胺类抗生素的检测限,同时指出了国标TTC法对6种广谱抗生素均不能检出欧盟法典规定的MRL残留浓度,而AOAO纸片法对其检测限均在MRL浓度范围内,且符合欧盟药典确定的最大残留量限制。建议乳中抗生素残留检测过程中,采用特异性与灵敏度高、经济简便、检测限达到MRLs规定的AOAO纸片法作为国标TTC检测法的补充。     

动物源性食品中抗生素残留的分类及检测方法的研究进展

随着抗生素在动物饲养过程中的普遍应用, 抗生素的不合理使用现象日益普遍, 造成动物源性食品(牛奶、肉类、水产品、鸡蛋、蜂蜜等)中抗生素的残留, 从而对人体健康造成潜在的危害, 因此动物源性食品中抗生素残留检测是控制食品质量安全的重要环节。本文对动物源性食品中抗生素残留的现状, 抗生素残留的种类及检测方法作了阐述, 并对抗生素检测方法的应用前景进行了展望, 以期为有关部门在检测动物源性食品中抗生素的残留的工作提供技术参考。     

牛乳中抗生素的残留及其控制对策

乳品中残留抗生素不仅危害人体的健康，而且也会对经济贸易造成影响。本文对牛乳中抗生素的残留来源、种类、危害、残留现状、检测方法进行了综述，并就控制牛乳中抗生素残留的对策谈了看法。     

动物源性食品中抗生素多残留检测的研究进展

研究动物源性食品中抗生素残留的分析检测方法,对保证我国食品安全至关重要。动物源性食品种类繁多、基质效应强,痕量抗生素残留检测的准确性和灵敏度取决于样品前处理效果。该文以动物源性食品中抗生素多残留的样品前处理方法为主线,重点综述近年来新型吸附剂、新前处理方法在动物源性食品中抗生素多残留超灵敏检测方面的研究进展,以期为动物源性食品中抗生素多残留的快速筛查和精准定量提供借鉴思路。     

广州市牛奶中抗生素残留的现状分析

为了控制牛乳中抗生素的残留,对广州市牛奶中抗生素残留进行监测。结果表明不同给药途径及剂量可造成不同的残留时间;生牛奶及奶粉中抗生素残留阳性率显著比消毒牛奶高;出口生牛奶抗生素残留阳性率显著比内销生牛奶高;进口消毒牛奶及奶粉中未检出抗生素。     

深圳市售奶粉中11种喹诺酮类抗生素含量检测分析

目的了解深圳地区市售奶粉喹诺酮类抗生素的污染情况。方法从深圳市各区超市和食品商店中购买不同种类的奶粉样品110份,用高效液相色谱-串联质谱法进行环丙沙星、氧氟沙星等11种喹诺酮类抗生素的检测。结果在深圳各区抽检的奶粉样品中未检出11种喹诺酮类抗生素,检出率为0。结论深圳市售奶粉喹诺酮类抗生素残留现象整体情况良好,但仍应加强奶源及奶粉生产过程中的监管,定期开展监测工作。     

Detection of antibiotics in sheep milk by receptor-binding assays

Receptor-binding assays to detect antibiotics in sheep milk were evaluated. Specificity of the Betastar Combo, SNAP and Twinsensor^BT tests was optimal using inhibitor-free bulk sheep milk (99–100%), and no differences between the visual or instrumental classification were found. For individual sheep milk free of antibiotics, specificity was elevated by the Betastar Combo and SNAP tests. However, lower specificity was obtained by the Twinsensor^BT test, especially in the last weeks of the lactation period. Regarding cross-reactions, interferences related to drugs other than β-lactams and tetracyclines were not detected. Furthermore, the use of azidiol, as a preservative of milk, had no effect on the test. In all cases, the detection capability was able to detect most β-lactams and tetracyclines at or below maximum residues limits. The receptor-binding tests evaluated showed a very good performance in the detection of antibiotics in sheep milk, thus being suitable for milk quality control programmes.     

牛奶中β-内酰胺和四环素类抗生素二联检测试纸条的初步研究

抗生素越来越多地被应用于畜牧业中,其在乳制品中的残留问题也备受关注.乳品中残留抗生素不仅危害人体的健康,而且影响经济贸易的正常进行.为适应基层检测牛奶中抗生素残留的需求,作者采用胶体金免疫层析方法,建立了可以同时测定牛奶中的β-内酰胺类抗生素和四环素类抗生素的二联胶体金试纸条.该方法简单可靠,可同时检测牛奶中12种β-内酰胺类抗生素和4种四环素类抗生素,是一种值得推广的定性筛选方法,可作为液相色谱等定量检测仪器法的补充.     

2019年我国不同地区牧场生牛乳中致病菌污染及抗生素耐药情况研究

目的 了解我国不同地区牧场生牛乳中致病菌污染情况和细菌耐药特征。方法 对2019年9—11月采集自43家不同地区牧场的53份生牛乳样品进行6种致病菌的分离鉴定,对分离株开展抗生素耐药性检测。结果 53份样品中大肠埃希氏菌、金黄色葡萄球菌、蜡样芽孢杆菌和单核细胞增生李斯特氏菌(单增李斯特菌)的污染率分别为62.26%(33/53)、20.75%(11/53)、5.66%(3/53)和3.77%(2/53),克罗诺杆菌和沙门氏菌均未检出。选取117株分离株进行药物敏感性实验,其中58株菌耐药,总体耐药率为49.57%(58/117);90株革兰氏阴性菌中有33株耐药,耐药率为36.67%(33/90);27株革兰氏阳性菌中有25株耐药株,耐药率为92.59%(25/17)。结论 不同地区牧场采集的生牛乳中细菌污染情况差异较大,污染随气温降低呈下降趋势。同时生乳中细菌分离株多重耐药率高,需进一步严格控制兽用抗生素的使用。     

Retention data for antibiotics commonly used for bovine infections

This study was designed to observe the maximum time that various antibiotics used in different ways as treatment of bovine infections persisted in milk after final treatment. Both Delvotest-P and Bacillus stearothermophilus (Difco) disc assay procedures were utilized for detection of antibiotic preparations used for treatment of mastitis. None persisted in milk longer than specified on their respective labels. Because antibiotic residues were detected in milk consequent to treatment for intrauterine infections, guidelines for withholding times following intrauterine treatment should be established.     

Contamination of milk and milk products by Yersinia enterocolitica at stages in the technological process of their production and manufacture

Contamination of milk and its products with Yersinia enterocolitica at various stages of the production process was studied for the first time. Yersinia were detected in fresh milk (at dairy farms, in tanks at reception compartments of dairy plants) and in pasteurized milk (in tanks at the plant, in paper-bags on sale). All Yersinia strains isolated from milk are pathogenic for man and highly resistant to antibiotics. A possible role of man, in particular of workers at dairy farms and plants, in Yersinia dissemination, is shown. Unlike milk, sour milk foodstuffs virtually do not participate in propagation of the infection.     

Evaluation of a microbiological indicator test for antibiotic detection in ewe and goat milk

Antibiotics are widely used for therapeutic and prophylactic purposes in dairy animals. The presence of residual antibiotics in milk could cause potentially serious problems in human health and have technological implication in the manufacturing of dairy products. The aim of this study was to evaluate Delvotest Accelerator (DSM Food Specialties, Delft, the Netherlands), a new system for a fully automated microbial test to detect antibiotic residues in ewe and goat milk. Forty-three samples of raw, whole, refrigerated bulk-tank milk samples (22 of ewe milk and 21 of goat milk) were analyzed during the whole lactation period. Four concentrations of 4 antibiotics were diluted in milk: penicillin G at 1, 2, 3, and 4 μg/L; sulfadiazine at 25, 50, 100, and 200 μg/L; tetracycline at 50, 100, 200, and 400 μg/L; and gentamicin at 25, 50, 100, and 200 μg/L. The detection limit of the Delvotest Accelerator was calculated as the range of antibiotic concentrations within which 95% of positive result lie. The range of detection limit of penicillin G and sulfadiazine was easily detected by Delvotest Accelerator at or below the European Union maximum residue limits, both for ewe and goat milk samples. In contrast, the system showed a lower ability to detect tetracycline and gentamicin both for ewe and goat milk samples. Very low percentages of false-positive outcomes were obtained. Lactation phase did not seem to be a crucial factor affecting the ability of the Delvotest Accelerator to detect spiked milk samples. A higher detection ability was observed for goat milk samples compared with ewe milk samples. A negative correlation between the percentage of positive milk samples detected and milk fat, protein, and lactose contents was observed for gentamicin only.     

Effects of mannan oligosaccharide or antibiotics in neonatal diets on health and growth of dairy calves

Seventy-two Holstein calves were used to study the effect of feeding antibiotics or mannan oligosaccharides (MOS) in milk replacer. Calves were fed a 20% protein, 20% fat milk replacer containing antibiotics (400 g/ton neomycin + 200 g/ton oxytetracycline), MOS (4 g of Bio-Mos/d), or no additive (control) for 5 wk. Milk replacer was reconstituted to 12.5% dry matter and fed at 12% of birth weight during wk 1 and 14% of birth weight in wk 2 to 5. Fecal scores were monitored 3 times per week; body weight, heart girth, withers height, hip height, and hip width were measured at birth and weekly to 6 wk of age. Addition of MOS or antibiotics increased the probability of normal scores for fecal fluidity, scours severity, and fecal consistency as compared to control calves during the course of the study. Consumption of calf starter increased at a faster rate in calves fed MOS, and these calves consumed more calf starter after weaning (wk 6), than those fed antibiotic. No treatment differences in growth measures, total blood protein, or blood urea nitrogen were detected during the trial. Addition of MOS or antibiotics to milk replacer improved fecal scores in calves. Feed intake was improved in MOS-fed calves compared to antibiotic-fed calves, but this difference did not result in growth differences during the experimental period. The results suggest that antibiotics in milk replacers can be replaced with compounds such as mannan oligosaccharides to obtain similar calf performance.