一起无证经营未经检疫肉品案的查处

１案情及处理 １９９８年 １２月１４日，公安部门将查封的某食品有限公司（主要业务是在玉林等地收购猪肉、牛肉加工肉脯，制成半成品后运往澳门作深加工）冷冻保存的４３９件（２５ ｋｇ／件）近１１ ０００ ｋｇ未经检疫的猪肉、牛肉依法移交我所处理。我所决定立案调查，当日随机采样６份，送广西区兽医卫生监督检验所检验。经综合判定，除４号和５号样品，其余均为病害肉或腐败肉。 该公司对检验报告有异议：（１）对２号、３号样品被判为病害肉或腐败肉不服。认为除沙门氏菌检验阳性外，ＰＨ值正常，其它各项均在鲜肉与次鲜肉之间，且…     

1月国内主要畜产品与饲料价格分析

18个抽样城市畜产品平均批发价格，羊肉最高（表1），其次是牛肉和猪肉，鸡肉最低。鸡肉地区差价最大，中部分别高于东、西部36．5％和4．2%；其次，猪肉批发价，中部分别高于东、西部13．7％、7．5％。与上月相比，猪肉、牛肉、羊肉和鸡肉平均价格基本持平，猪肉上涨4．0％。与去年同期相比，牛肉价格上涨8．5％，猪肉下降12．2％，而羊肉批发价基本持平。     

2月国内主要畜产品与饲料价格分析

18个抽样城市畜产品肉类平均批发价格，羊肉最高（表1），其次是牛肉和猪肉，鸡肉最低。猪肉地区差价最大，中部分别高于东、西部17．1％和11．0％；其次，牛肉批发价，中部分别高于东、西部13．3％和7．1％。与上月相比，牛肉、羊肉和鸡蛋平均价格基本持平，而猪肉、鸡肉价格分别下降4．8％和3．4％。与2008年同期相比．牛肉、鸡蛋价格基本持平；     

6月份畜产品批发价格动态分析

据农业部“全国农产品批发市场信息网”监测，2005年6月份全国城乡批发市场“菜篮子”产品价格与上月相比（以下称环比），猪肉、牛肉价格持平，鸡蛋价格略涨；与去年同期相比（以下称同比），猪肉价格略降，牛肉、鸡蛋价格上涨。     

3月国内主要畜产品与饲料价格分析

18个抽样城市畜产品肉类平均批发价格，羊肉最高（表1），其次是牛肉和猪肉，鸡肉最低。牛肉地区差价最大，中部分别高于东、西部11．6％和9．99%；其次，猪肉批发价，中部分别高于东、西部19．7％、8．09%。与2月相比，牛肉、羊肉、鸡肉和鸡蛋平均批发价基本持平，而猪肉价格下降6．7％，牛奶价格上涨3．8％。与2008年同期相比，牛肉、鸡蛋价格基本持平；而猪肉、羊肉、和鸡肉价格则分别下降26．29%、2．8％和8．5％。     

5月国内主要畜产品与饲料价格分析

21个抽样城市畜产品肉类平均批发价格,羊肉最高（表1）,其次是牛肉和猪肉,鸡肉最低。猪肉地区差价最大,中部分别高于东、西部19．5％、12．0％;其次。鸡肉批发价西部分别高于东、中部14．8％、4．1％。与4月相比,牛肉、鸡肉和牛奶价格基本持平;而猪肉价格下降9．8％;羊肉和鸡蛋价格分别上涨4．2%和5．0％。与2008年同期相比,牛肉、羊肉和鸡蛋价格基本持平;     

11月国内主要畜产品与饲料价格分析

12个抽样城市畜产品平均批发价格,牛肉最高（表1）,其次是羊肉和猪肉,鸡肉最低。猪肉地区差价最大,中部分别高于东、西部23．7％和24．3％;其次,羊肉批发价,东部和西部分别高于中部21．1％和20．4％。牛奶价东部分别高于中、西部6．7％和30．4％。与10月相比,牛肉、猪肉、羊肉、鸡肉和牛奶平均价格基本持平,鸡蛋下降14．3％。与2007年同期相比,牛肉、鸡肉和羊肉价格分别高21．O%、14．2％和8．6％,猪肉下降11．5％,鸡蛋低4．0％。     

4月国内主要畜产品与饲料价格分析

18个抽样城市畜产品肉类平均批发价格，羊肉最高（表1），其次是牛肉和猪肉，鸡肉最低。猪肉地区差价最大，中部分别高于东、西部19．8％和5．9％；其次，羊肉批发价东部分别高于中、西部8．9％、2．0％。与3月相比，牛肉、羊肉、鸡肉和牛奶价格基本持平；     

德刊评述中国畜禽市场

1中国红肉生产增长 中国境内禽流感的发生导致了对牛肉和猪肉需求的增长。美国驻华使馆预测2006年中国猪肉生产增长4．7％，总量达到5200万t（表1）。     

石河子地区动物性食品中单核细胞增生李斯特菌的检测

目的了解新疆石河子地区动物性食品中单核细胞增生李斯特氏菌(LM)污染状况。方法在石河子地区选取5个具有代表性动物性食品零售点,对最常食用的生鲜猪肉、牛肉、羊肉、鸡肉、冻鸡肉、冻虾和冻带鱼8类动物性食品进行随机采样,采用病原分离培养和PCR法对样品中的单核细胞增生李斯特氏菌进行检测。结果检测8类249份食品样品,细菌分离鉴定阳性样品12份,平均阳性率4.82%;PCR法检测阳性样品36份,平均阳性率为14.46%。结论石河子动物性食品中LM的污染比较普遍,尤以冻鸡肉和冻虾LM污染较重,新鲜猪肉、牛肉和羊肉LM污染程度较轻。     

西宁市售动物性食品中肠出血型大肠杆菌O157：H7的检测

对西宁市售的动物性食品羊肉(20份)、牛肉(20份)、猪肉(20份)、鸡肉(20份)、牛奶(20份)、卤肉(10份)进行了大肠杆菌O157:H7检验,各样品先用mEC肉汤增菌,然后在选择性培养基TC-SMAC、MUG-LST培养此菌,经微量生化实验初步鉴定。结果是从110份样品中分离出1株大肠杆菌O157:H7,总检出率为0.9%;说明在西宁市售动物性食品中检出了大肠杆菌O157:H7。     

Isolation and characterization of Shiga toxin-producing Escherichia coli O157:H7 from beef,pork and cattle fecal samples in Changchun,China

Meat samples and fecal specimens from adult cattle were collected in Changchun, China and were examined for presence of Shiga toxin-producing Escherichia coli (STEC) serogroup O157. STEC O157 strains were isolated from 2 (5%) of 40 beef, 1 (3.3%) of 30 pork, and 3 (1.7%) of 176 adult cattle fecal samples. The strains belonged to phage types (PT) 4, 8, or 47. Two beef strains and a strain previously isolated from a patient in Shandong, China, were PT-4 and showed a similar PFGE pattern, suggesting the possibility of food-borne transmission. It is suggested that cattle are a reservoir of STEC O157:H7 and meat products are contaminated by this pathogen in Changchun, China as well as in other countries.     

大肠杆菌O157∶H7实时定量PCR检测方法的建立

根据GenBank公布的大肠杆菌O157∶H7的Flic(H7)基因序列进行同源性比较分析,选择保守序列设计一对特异性扩增引物,通过优化反应条件,建立一个用于大肠杆菌O157∶H7快速定量检测的实时定量PCR方法。该方法的最低检测极限是103CFU/mL,敏感性比常规PCR提高10倍。方法重复性好、特异性强,重复性检测的变异系数均小于2%;只能检测大肠杆菌O157∶H7,对非大肠杆菌O157∶H7血清型细菌、猪链球菌2型、副猪嗜血杆菌无反应。利用此方法对模拟样本进行定量检测,其结果与平板细菌计数基本一致,表明此方法可作为大肠杆菌O157∶H7快速诊断和疫情监测的一种快速、准确、简便的检测工具。     

Escherichia coli O157:H7 and non-O157 Shiga toxin-producing E. coli in healthy cattle, sheep and swine herds in Northern Spain

Three-hundred and forty-five herds (17 swine, 122 dairy sheep, 124 beef and 82 dairy cattle) were investigated for prevalence of Shiga toxin-producing Escherichia coli (STEC). Rectal faecal samples were selectively enriched and then examined by immunodetection techniques (Immunomagnetic Separation with anti-E. coli O157 Dynabeads, ImmunoMagnetic cell Separation (IMS) and automated enzyme-linked fluorescent immunoassay using VIDAS) and polymerase chain reaction (PCR) (rfbE and fliC genes) to assess the prevalence of E. coli O157:H7. Prevalence of non-O157 STEC was estimated by PCR screening for stx genes of 10 lactose-positive colonies grown on MacConkey agar after enrichment. PCR was used on all STEC isolates to detect stx(1), stx(2), eaeA and E-hlyA genes. Both immunodetection methods showed a moderate-good level of agreement (kappa = 0.649) but IMS showed 87.5% complementary sensitivity. Prevalence of positive herds for E. coli O157:H7 was estimated at 8.7% for sheep and 3.8% for cattle, whereas all the porcine herds tested negative. Non-O157 STEC were also absent from swine, but were isolated more frequently from ovine (50.8%) than bovine herds (35.9%). Within-herd prevalences of excretion of E. coli O157:H7 established by individual testing of 279 sheep (six herds) and 30 beef cattle (one herd) were 7.3% and 6.7% respectively. PCR analysis of 49 E. coli O157:H7 and 209 non-O157 isolates showed a different distribution of virulence genes. All E. coli O157:H7 were stx(2) gene-positive, eaeA was detected in 95.9%, and the toxigenic profile stx(2)/eaeA/E-hlyA was present in 75.5% of the isolates. Among the non-O157 STEC, prevalence of eaeA was significantly lower (5.3%) and E-hlyA was present in 50.2% of the isolates but only sporadically associated with eaeA. stx(2) was predominant in non-O157 isolates from cattle, whereas in sheep the combination stx(1)/stx(2) was more prevalent. This study demonstrated the wide distribution of STEC in ruminant herds, which represent an important reservoir for strains that pose a potential risk for human infections.     

肠出血性大肠杆菌O157∶H7 EMA-PCR检测技术的建立

肠出血性大肠杆菌O157∶H7是一种重要的人畜共患传染病病原菌。为建立一种特异、灵敏的O157∶H7新型检测技术,以O157抗原基因(rfbE基因)为模板设计特异性引物,利用叠氮溴化乙锭(ethidium monoazide bromide,EMA)处理菌液,沸水浴法制备细菌裂解液,优化PCR条件,建立一种快速、有效的O157∶H7活菌EMA-PCR检测方法。结果显示:EMA-PCR可从rfbE基因阳性菌株CVCC248和两株临床分离菌株cd0912、cd0803中扩增出大小为495 bp的特异性条带,检测灵敏度可达12 CFU/mL。经EMA处理,从含有1%～100%O157∶H7 CVCC248活菌混合悬液制备的DNA中均可扩增出目的片段。因此,成功建立了肠出血性大肠杆菌O157∶H7的EMA-PCR检测方法;该方法可避免因分析的样品中含有死细菌而造成的假阳性检测结果,检测的准确性和真实性较传统PCR大大提高。O157∶H7 EMA-PCR技术的建立为O157∶H7的临床诊断提供了新的方法,具有重要的实际应用价值和良好的应用前景。     

Prevalence of Escherichia coli O157:H7 in white-tailed deer sharing rangeland with cattle.

OBJECTIVE: To determine the prevalence of fecal shedding of Escherichia coli O157:H7 in white-tailed deer (Odocoileus virginianus) with access to cattle pastures. DESIGN: Survey study. SAMPLE POPULATION: 212 fecal samples from free ranging white-tailed deer. PROCEDURE: Fresh feces were collected on multiple pastures from 2 farms in north central Kansas between September 1997 and April 1998. Escherichia coli O157:H7 was identified by bacterial culture and DNA-based methods. RESULTS: Escherichia coli O157:H7 was identified in 2.4% (5/212) of white-tailed deer fecal samples. CONCLUSIONS AND CLINICAL RELEVANCE: There is considerable interest in the beef industry in on-farm control of E coli O157:H7 to reduce the risk of this pathogen entering the human food chain. Results of our study suggest that the design of programs for E coli O157:H7 control in domestic livestock on pasture will need to account for fecal shedding in free-ranging deer. In addition, the results have implications for hunters, people consuming venison, and deer-farming enterprises.     

High occurrence of Shiga toxin-producing Escherichia coli (STEC) in healthy cattle in Rio de Janeiro State, Brazil

In order to evaluate the prevalence of Shiga toxin-producing Escherichia coli (STEC) strains, 197 fecal samples of healthy cattle from 10 dairy farms, four beef farms and one slaughterhouse at Rio de Janeiro State, Brazil, were examined for Shiga toxin (Stx) gene sequences by polymerase chain reaction (PCR). For presumptive isolation of O157:H7 E. coli, the Cefixime-potassium tellurite-sorbitol MacConkey Agar (CT-SMAC) was used. A high occurrence (71%) of Stx was detected, and was more frequently found among dairy cattle (82% vs. 53% in beef cattle), in which no differences were observed regarding the age of the animals. Dot blot hybridization with stx1 and stx2 probes revealed that the predominant STEC type was one that had the genes for both stx1 and stx2 in dairy cattle and one that had only the stx1 gene for beef cattle. Three (1.5%) O157:H7 E. coli strains were isolated from one beef and two dairy animals by the use of CT-SMAC. To our knowledge, this is the first report of O157:H7 isolation in Brazil. A PCR-based STEC detection protocol led to the isolation of STEC in 12 of 16 randomly selected PCR-positive stool samples. A total of 15 STEC strains belonging to 11 serotypes were isolated, and most of them (60%) had both stx1 and stx2 gene sequences. Cytotoxicity assays with HeLa and Vero cells revealed that all strains except two of serotype O157:H7 expressed Stx. The data point to the high prevalence of STEC in our environment and suggest the need for good control strategies for the prevention of contamination of animal products.     

Dietary monensin level, supplemental urea, and ractopamine on fecal shedding of Escherichia coli O157:H7 in feedlot cattle

Inclusion of distillers grains (DG) in cattle diets has been shown to increase fecal shedding of Escherichia coli O157:H7. It is hypothesized that altered gut fermentation by DG may be responsible for the positive association. Therefore, feed additives affecting ruminal or hindgut fermentation of DG also may affect fecal shedding of E. coli O157:H7. The objectives of the study were to evaluate effects of monensin (33 or 44 mg/kg of DM), supplemental urea (0, 0.35, or 0.70% of DM), and ractopamine (0 or 200 mg/steer daily administered during the last 42 d of finishing) in a steam-flaked corn grain-based diet containing 30% wet sorghum DG on fecal shedding of E. coli O157:H7. Seven hundred twenty crossbred beef steers, housed in 48 pens (15 steers/pen), were assigned to dietary treatments in a randomized complete block design with a 2 × 3 × 2 factorial treatment arrangement. Fresh pen floor fecal samples (10 per/pen) were collected every 2 wk for 14 wk (July through November) and cultured for E. coli O157:H7. Isolation of E. coli O157:H7 was by selective enrichment of fecal samples in an enrichment broth, immunomagnetic separation, followed by plating onto a selective medium. Samples that yielded sorbitol-negative colonies, which were positive for indole production, O157 antigen agglutination, and contained rfbE, fliC, and stx2 were considered positive for E. coli O157:H7. Fecal prevalence data were analyzed as repeated measures using negative binomial regression to examine effects and interactions of sampling day, urea, monensin, and ractopamine. Mean fecal prevalence of E. coli O157:H7 was 7.6% and ranged from 1.6 to 23.6%. Cattle fed monensin at 44 mg/kg of feed had less (P = 0.05) fecal E. coli O157:H7 prevalence than cattle fed 33 mg/kg (4.3 vs. 6.8%). Although the reason for the reduction is not known, it is likely because of changes in the microbial ecosystem induced by the greater amount of monensin in the hindgut. Supplemental urea at 0.35 or 0.70% had no effect (P = 0.87) on fecal shedding of E. coli O157:H7. Fecal prevalence of E. coli O157:H7 were 5.3, 5.7, and 5.9% for groups fed 0, 0.35, and 0.7% urea, respectively. The inclusion of ractopamine at 0 or 200 mg/(animal?d) had no effect (P = 0.89) on fecal prevalence of E. coli O157:H7 (4.4 vs. 4.0%). Additional research is needed to confirm the reduction in fecal shedding of E. coli O157:H7 in cattle fed monensin at 44 mg/kg of feed compared with cattle fed 33 mg/kg of feed.     

大肠杆菌O157∶H7单克隆抗体胶体金免疫层析检测试纸条的研制

用E.coliO157∶H7菌体免疫BALB/c鼠,制备免疫脾细胞,与SP2/0骨髓瘤细胞融合,获得了16株分泌单克隆抗体（mAb）的杂交瘤细胞株。其中,1D3、2E7和2H7三株为O157∶H7特异单克隆抗体,Ig亚类分别为IgMκ、IgG2bκ和IgG2bκ,腹水抗体ELISA效价分别为103、105和106。用纯化的单克隆抗体2E7标记胶体金,制备金标抗体玻璃纤维素膜;将纯化的2H7和羊抗鼠IgG分别作为检测和对照捕捉抗体包被于硝酸纤维素膜（NC）上;组装成双抗夹心法O157∶H7胶体金免疫层析检测试纸条。用该试纸条可特异检测O157∶H7,敏感度为106CFU/mL,与相同单克隆抗体2H7和2E7建立的O157∶H7夹心ELISA检测方法的敏感度相当,试纸条简便快速,在1~5 min内可得出检测结果,便于O157∶H7的临床快速诊断与现场检测样品的快速筛查。     

The prevalence of verotoxins, Escherichia coli O157:H7, and Salmonella in the feces and rumen of cattle at processing.

Fecal samples collected from cattle at processing during a 1-year period were tested for verotoxins (VT1, VT2), Escherichia coli O157:H7, and Salmonella. Verotoxins were detected in 42.6% (95% CI, 39.8% to 45.4%), E. coli O157:H7 in 7.5% (95% CI, 6.1% to 9.1%), and Salmonella in 0.08% (95% CI, 0.004% to 0.5%) of the fecal samples. In yearling cattle, the median within-lot prevalence (percentage of positive samples within a lot) was 40% (range, 0% to 100%) for verotoxins and 0% for E. coli O157:H7 (range, 0% to 100%) and Salmonella (range, 0% to 17%). One or more fecal samples were positive for verotoxins in 80.4% (95% CI, 72.8% to 86.4%) of the lots of yearling cattle, whereas E. coli O157:H7 were detected in 33.6% (95% CI, 26.0% to 42.0%) of the lots. In cull cows, the median within-lot prevalence was 50% (range, 0% to 100%) for verotoxins and 0% (range, 0% to 100%) for E. coli O157:H7 and Salmonella (range, 0% to 0%). Verotoxins were detected in one or more fecal samples from 78.0% (95% CI, 70.4% to 84.2%) of the lots of cull cows, whereas E. coli O157:H7 were detected in only 6.0% (95% CI, 3.0% to 11.4%) of the lots of cull cows. The prevalence of verotoxins in fecal samples was lower in yearling cattle than in cull cows, whereas the prevalence of E. coli O157:H7 in fecal samples was higher in yearling cattle than in cull cows. The prevalence of E. coli O157:H7 in fecal samples was highest in the summer months. Rumen fill, body condition score, sex, type of cattle (dairy, beef), and distance travelled to the plant were not associated with the fecal prevalence of verotoxins or E. coli O157:H7. The prevalence of verotoxins in fecal samples of cull cows was associated with the source of the cattle. It was highest in cows from the auction market (52%) and farm/ranch (47%) and lowest in cows from the feedlot (31%). In rumen samples, the prevalence of verotoxins was 6.4% (95% CI, 4.2% to 9.4%), and it was 0.8% (95% CI, 0.2% to 2.3%) for E. coli O157:H7, and 0.3% (95% CI, 0.007% to 1.5%) for Salmonella.