西藏林芝地区市售家禽禽流感免疫状况调查

为了解林芝地区市售家禽禽流感免疫状况,于2008年10～12月间采集了5种家禽的249份血清样本,采用HA和HI试验进行了禽流感血清抗体的检测,发现在5种家禽的249份血清中检出了179份AIV阳性抗体,其中H5阳性数32份,阳性率为12.9%;H9阳性数43份,阳性率为17.3%;H1阳性数19份,阳性率为7.6%;H3阳性数85份,阳性率为34.7%。表明林芝地区市售家禽禽流感免疫状况仍需进一步改进。     

青海省海晏县绵羊布氏杆菌病的调查

用布氏杆菌试管凝集试验(SAT),对海晏地区的绵羊进行了布氏杆菌血清抗体的检测,共检397份血清样品,检出阳性血清2份,阳性率为0.50%;其中:成年母羊血清233份,检出阳性1份,阳性率为0.43%;后备母羊血清91份,检出阳性1份血清,阳性率为1.10%;羯羊血清52份,阳性率为0%;种公羊21份,也未检出阳性。     

牦牛病毒性腹泻病PCR诊断方法的建立

采用阻断ELISA方法对来自天峻县的327份牦牛血清进行了牛BVDV特异性抗体的检测,共检出231份血清阳性,血清阳性率为70.64%。其中:在135份野牦牛血清中检出110份阳性血清,阳性率为81.48%;在192份家牦牛血清中检出阳性121份,阳性率为63.02%。从231份ELISA检测阳性血清中随机抽取了20份,采用RT-PCR方法进行检测,结果共检出18份样品为BVDV/MV RT-PCR阳性,阴性血清未扩增出E0基因,RT-PCR方法检测结果与ELISA方法符合率为90%。     

大理州鸡沙门氏菌血清学调查

为了解大理州鸡群沙门氏菌的感染情况,从大理州9个县(市)的规模化养鸡场及散养场(户),随机采集鸡的血清样本1 424份,进行鸡沙门氏菌血清学相关检测。结果：1 424份血清样品中,检出阳性样品469份,平均阳性率为32.94%。其中规模化养鸡场检测数为1 055份,阳性318份,阳性率为30.14%;散养场(户)17家,抽检样品369份,阳性151份,阳性率为40.92%。抽检样品中,母鸡抽检754份,检测阳性数为264份,阳性率为35.01%;公鸡抽检670份,检测阳性数为205份,阳性率为30.60%。结论：大理州各地区养殖鸡群中普遍存在沙门氏菌的感染,规模化养鸡场鸡沙门氏菌感染率低于散养户,母鸡群比公鸡群的阳性率高。通过对大理州鸡群鸡沙门氏菌感染现状调查,为大理州鸡沙门氏菌的防控及净化提供了依据。     

昆明地区犬细小病毒病的感染状况调查

为掌握昆明地区犬细小病毒病的感染情况,对昆明西山区、官渡区、五华区未免疫犬中各随机抽取50只,共计150只进行了检测.结果表明,检测犬150只,共检出阳性41只,阳性率为27.3%.西山区检出阳性13只,阳性率26%;官渡区检出阳性16只,阳性率32%;五华区检出阳性12只,阳性率24%.     

新疆边境地区奶牛结核病流行病学调查研究

首先用国标(PPD)进行检测,对阳性牛开展进口牛型、禽型结核菌素(PPD)试验,同时进行γ-干扰素试验等验证及流行病学调查,收集各地相应流行菌株,有条件地开展血清学试验及分子流行病学研究工作。每年在定点4个牛场检测样品数为700份,三年项目执行期间去检测奶牛5406头。国产PPD进行检测,检出阳性牛59头,阳性率为1.09%,欧盟PPD比较试验检出阳性牛47头,γ-干扰素试验检出阳性牛24头,国产(PPD)试验与γ-干扰素试验的比较符合率为41%。实验结果显示,国内产结核菌素敏感性较高,进口结核菌素敏感性适中,可以看出PPD试验特异性较低,会出现一定比列的假阳性,造成误判,而γ-干扰素试验有较强的特异性。通过这三年对定点地区定点牛群奶牛结核病的连续检测,无害化处理阳性牛,使定点牛群的阳性感染率同比下降显著。     

民和县某奶牛场流产类疫病的血清学调查

本文采用虎红平板凝集试验和正向间接血凝试验对民和县某奶牛场奶牛进行了流产类疫病的血清学检测。结果从第一批次的178份血液样品中未检出布病阳性血清;在第二批次的160份血清样品中,检出衣原体阳性3份,阳性率为1.9%;从第三批次的96份血清样品中,检出弓形虫阳性48份,阳性率为50%。     

消毒奶中抗生素残留的调查

随机采取市售消毒奶150份，采用TTC法进行抗生素残留检测，结果表明：检出有抗生素残留的阳性乳3份，均为省内产品，阳性率占总份数的2．0％，其余147份均为阴性，即无抗生素残留。     

青海省三角城种羊场部分种羊中流产类疾病的血清学检测

应用布鲁氏菌病RBPT(Rose-Bengal Plate Agglutination Test)、衣原体和弓形虫IHA(Indirect Hemagglutination Assay),对来自青海省三角城种羊场的59份试情公羊的血清、60份后备母羊的血清进行特异性血清抗体的检测。结果:在119份被检血清中,检出衣原体阳性血清3份,阳性率为2.52%,其中在59份试情公羊血清中检出3份,阳性率5.08%;在后备母羊的血清未检出衣原体阳性血清;所有的血清中均未检测到布氏杆菌和弓形虫阳性血清。     

乌鲁木齐市市售牛奶中抗生素残留调查及生鲜乳理化分析

对乌鲁木齐市售纯牛奶和生鲜牛奶中抗生素残留情况进行调查,同时对某奶牛场中生鲜牛奶中的成分进行分析,为加强新疆乳制品质量控制提供依据。采用TTC法(GB 4789.27-2008)检测乳品中抗生素残留情况,采用乳成分分析仪和体细胞计数仪测定生鲜乳中脂肪、蛋白、乳糖、体细胞数。检测结果显示生鲜牛奶72份和市售包装纯牛奶及袋装纯牛奶83份的阳性率均为0%。该奶牛场中生鲜牛奶中体细胞数50万个/ml为70.45%,其脂肪含量为3.93g/100g、蛋白质含量为3.84g/100g、乳糖含量为5.61g/100g。乌鲁木齐市售纯牛奶和生鲜牛奶中没有检测出抗生素残留,奶牛场中生鲜乳成分达到国家标准,为市民提供了营养健康的奶制品。     

纯牛奶中抗菌药物残留的检测

为了解山西省交城县各大超市销售纯牛奶中抗菌药物残留情况，随机采购此牛奶50份，分别用TTC法、微生物检测法和酶标免疫分析法进行抗生素残留检测。TTC法检测出阳性率为8％，可疑率为6％；微生物法检测出青霉素类残留阳性率为10％。酶标免疫分析法检测出四环素类阳性率为8％；链霉素残留阳性率为22％；磺胺二甲嘧啶检测全部为阴性。结果表明，交城县各大超市售纯牛奶中有部分存在抗菌药物残留。     

牦牛乳中沃氏葡萄球菌的分离鉴定与耐药性分析

在利用Baird-Parker(BP)琼脂平板培养基分离牦牛乳中金黄色葡萄球菌的过程中分离得到经基质解析电离飞行时间质谱(matrix-assisted laser desorption ionization-time of flight-mass spectrometry,MALDI-TOF-MS)鉴定为沃氏葡萄球菌的微生物,对其进行生化鉴定和抗生素药敏及抑菌实验,同时对牦牛乳样品中的抗生素残留进行测定。结果表明:该菌具有沃氏葡萄球菌的生化特征,对大部分抗生素极敏感,仅复方新诺明对其没有抑制作用;牦牛乳样品均为抗生素残留阴性。虽然在牦牛乳中检测出了条件致病菌沃氏葡萄球菌,但因乳样品来源的环境纯净使其对大部分抗生素敏感。     

辽宁省原料乳中β-内酰胺酶的检测及结果分析

为了解辽宁省原料乳中是否含有β-内酰胺酶抗生素残留,对其质量状况进行调查.采用《乳及乳制品中舒巴坦敏感β-内酰胺酶类药物检验方法——杯碟法》检验方法对辽宁省送检的186批次原料乳样品进行检测.结果 共检出23批次β-内酰胺酶阳性样品,原料乳阳性样品检出率高达12.4％.调查发现,辽宁省原料乳中β-内酰胺酶检出率较高,在...     

Antibiotic residues (bacterial inhibitory substances) in the milk of cows treated under label and extra-label conditions

The objectives of this study were to describe the depletion pattern of antibiotic residues (microbial inhibitory substances) from the milk of cows treated under field conditions of clinical disease and antibiotic administration, including both label and extra-label use, and to determine if the type of extra-label use, the route of administration, and the drug used were factors associated with prolonged shedding of residues in milk.

Milk samples from 138 cows, treated with a variety of antibiotic products on farms in southwestern Ontario in 1989 and 1990, were collected before treatment and for six days after cessation of treatment. Samples were tested for antibiotic residues with the Brilliant Black reduction test (BR-test) and the Bacillus stearothermophilus var calidolactis disc assay. In 13/138 (9.4%) of cow treatments, at least one milk sample was positive on both antibiotic residue tests after the label milk withholding time for the drug(s) used. In ten of these instances, the antibiotics were administered in extra-label fashion and in three the drugs were reportedly used according to label instructions. Extra-label use of antibiotics was significantly associated with increased risk of antibiotic residues in milk beyond the label withholding time. No significant differences in risk were observed among the various antibiotic products used in the study.

The farms involved in this study were selected on the basis of their proximity to our laboratory; therefore, the frequency of antibiotic residue detection after withholding times may not be indicative of the provincial or national situation. If farmers and veterinarians find themselves in a situation where extra-label use of an antibiotic is necessary, use of an alternative antibiotic that can be used at label dose and with a known withdrawal time may avoid a problem with residues.

     

鲜牛奶中抗生素残留的检测

随机采取市售鲜牛奶250份,采用TTC法进行抗生素残留检测。表明:检出有抗生素残留的阳性乳2份,均为西宁市区产品,阳性率占0.8%,其余248份均为阴性,无抗生素残留。     

2017年酒泉市部分地区市动物性食品喹诺酮类抗生素残留情况调查与分析

研究旨在初步了解并分析甘肃省酒泉市部分地区市动物性食品喹诺酮类抗生素残留情况,为相应的膳食安全评估提供基础数据。于2017年3—10月在酒泉市部分地区随机采集动物性食品共235份,应用超高效液相色谱-串联质谱法对被检样品中喹诺酮类抗生素残留进行检测与分析。结果表明:235份样品中有14份样品检测含有喹诺酮类抗生素残留,检出率5.96%,其中猪肉、鸡肉、鸡蛋、羊肉和牛肉的检出率分别为4.56%(2/43)、4.17%(1/24)、25.00%(5/20)、4.69%(6/128)和0.00%(0/20),且2份鸡蛋样品检测超标,超标率0.85%(2/235);此外,14份阳性样品中恩诺沙星的检出率最高,为64.28%(9/14)。说明酒泉市部分动物性食品存在喹诺酮类抗生素残留,对消费者健康造成一定的威胁,应引起相关部门的重视。     

乳房淋巴结内注射胸腺五肽治疗奶牛隐性乳房炎的研究

将患隐性乳房炎的奶牛30头随机分为5组,3个试验组奶牛分别在乳房淋巴结内注入低、中、高剂量的胸腺五肽（TP-5）;阳性药物对照组奶牛在乳房内灌注＂乳炎＂（主要含林可霉素和新霉素）;空白对照组,不作任何处理。治疗前和治疗后1、2、3周采集奶样进行细菌学检查和体细胞计数（SCC）。停药后4d之内每天采样进行牛奶抗生素残留检测。结果表明,和空白对照组比较,经药物治疗后各组感染乳区有不同程度减少,牛奶SCC减少的幅度依次为阳性药物对照组〉TP-5高剂量组〉TP-5中剂量组〉TP-5低剂量组。＂乳炎＂治疗组在停药后3d之内可以在牛奶中检测到抗生素残留,而TP-5则没有。因此,TP-5对奶牛隐性乳房炎具有治疗作用,并且不会在牛奶中造成有害的残留。     

牛奶中抗生素残留及其三种检测方法的比较分析研究

抗生素残留不仅危害人类健康,同时也影响牛奶的品质,造成经济损失。本文讨论了牛奶中抗生素残留的来源与途径和危害,通过比较分析三种检测方法,找出一种能够相对的可同时检测多种样品的方法,更有效的使牛奶供应去抗生素化。     

Factors associated with the risk of antibiotic residues and intramammary pathogen presence in milk from heifers administered prepartum intramammary antibiotic therapy

Heifers (n=136) from 5 herds were treated with a commercially available beta-lactam intramammary (IMM) antibiotic preparation containing cephapirin sodium at 10-21 d prior to anticipated parturition to evaluate the risk of antibiotic residues occurring in milk postpartum and to determine factors associated with antibiotic residues and IMM pathogen presence in milk postpartum. Mammary secretions collected from quarters before antibiotic administration and during weeks 1, 2 and 3 postpartum were analyzed for mastitis pathogens. Composite milk was collected at milkings 3, 6 and 10 postpartum and analyzed for beta-lactam residues using a microbial inhibition antibiotic residue screening test. Antibiotic residues were confirmed with beta-lactamase treatment and re-tested for residues. Residues were detected in 28.0, 8.82 and 3.68% of milk samples obtained at the third, sixth, and tenth milking postpartum, respectively. Increases in interval between prepartum antibiotic therapy and parturition and an increase in the postpartum interval to sampling were associated with a decrease in risk of antibiotic residues. The presence of antibiotic residues in milk at the third milking was associated with a reduced risk for IMM pathogen prevalence in the first 21 d postpartum. Lower somatic cell counts, an increase in mean milk yield over 200 days in milk and a reduction in IMM pathogen prevalence were associated with the presence of an antibiotic in milk postpartum. Screening milk for antibiotic residues in milk postpartum following prepartum antibiotic therapy in heifers is recommended to reduce the risk for antibiotic residue contamination of milk.     

超高效液相色谱-串联质谱法测定牛乳、发酵乳和乳粉中四环素类药物残留

建立超高效液相色谱-串联质谱法同时检测牛乳、发酵乳和乳粉3 种基质中4 种四环素类药物残留的检测方法。对前处理方法和仪器上机条件进行研究。以EDTA-Mcllvaine缓冲液进行提取,经HLB固相萃取柱净化,甲醇-乙酸乙酯（1∶9,V/V）洗脱,氮吹后复溶,采用电喷雾离子源正离子模式、多反应监测模式进行检测。结果表明：乳粉中四环素、土霉素、金霉素和强力霉素的定量限均为10 μg/kg;液态乳和发酵乳中4 种药物的定量限均为2 μg/kg;四环素类药物添加量为2～100 μg/kg时,回收率为63.1%～1