Study On The Surface Microbial Contamination Of Egg Shell And The Biological Characteristics Of Escherichia Coli In Different Culture Patterns

Poultry eggs contain high nutrient content which is easily absorbed by the body and is a necessity for People's Daily food structure.But the shell surface are susceptible to bacterial contamination,which not only cause eggs preservation time and quality to drop,alsoincreased the eggs source people beast comorbidities,biological pollution control on the surface of the shell are attaches great importance to the government and consumer.This article to semi-enclosed and totally enclosed 2mode production sheds egg shell surface bacteria and airbome bacteria as the reasearch object,10 times by plate dilution method to determine the egg shell sueface microbial contamination condition;Using the conventional bacterial separation culture to identify e.coil species with 16 S rDNA sequence analysis;The serum and drug resistance of e.coil were analyzed and analyzed by using the vitrified coagulation test and the k-b paper diffusion method,and the main results were as follows:1?Detection of bacterial contamination in air and its eggshells in two farming modes.The bacterial contamination of eggshell surface was correlated with the concentration of airborne bacteria in chicken coop.When the chicken house ambient air bacterial pollution is serious,the egg shell surface bacterial contamination will be more obvious.Compared with the bacterial culture of egg shells in the production of eggshells,the bacterial contamination of egg shells was relatively light in the whole closed culture mode.2 ? Storage time on the production of eggs in different farming patterns of eggshell surface bacterial pollutionThe length of egg storage time had an effect on the bacterial changes in egg shells of two farming models.The total number of colonies on egg shells showed an increasing trend with the increase of storage time,but the growth rate of different culture patterns(closed and semi-closed)was different.When stored at 25 ? for 21 days,24 days and 27 days,semi-The total number of colony on the surface of the eggshell was more than 5 × 104 CFU / g(national standard for food safety).However,the total number of shells on the surface of the enclosed aquaculture model was consistent with the national standard for food safety.3? Isolation and Identification of Escherichia coli from Egg Shell Surface15 strains of Escherichia coli were isolated from eggs(semi-closed and fully enclosed culture)shells by conventional bacterial isolation and culture combined with16 S rDNA sequence analysis.4?Egg shell surface of E.coli serotype,drug resistance analysis.Two kinds of breeding patterns produce eggs on the egg shell surface of E.coli with superior serotypes.The results showed that the serotypes of 9 strains of Escherichia coli belonged to single factor serotype,accounting for 60% of the total;6strains of E.coli were mixed serotypes,accounting for 40% of the total strains.Egg shell(semi-enclosed culture mode)on the surface of E.coli dominant serotype O101;Eggshell(fully enclosed culture mode)on the surface of E.coli dominant serotype O65.The eggshell surface of Eggs produced by two kinds of breeding patterns showed multiple drug resistance,but the degree of drug resistance of E.coli was relatively light.Egg shell(closed)surface of E.coli on penicillin,amoxicillin,doxycycline have a strong resistance,resistance rates were 26.67%,33.33%,33.33%;eggshell(semi-closed)The surface of Escherichia coli had strong resistance to ampicillin,doxycycline and penicillin,and the resistance rates were 53.33%,46.67% and 46.67%respectively.The predominant serotype O101 of Escherichia coli was resistant to penicillin and amoxicillin up to 100%,and O65 Escherichia coli was resistant to penicillin up to 95.12%.In conclusion,the bacterial contamination on the egg shell surface was correlated with the concentration of airborne bacteria in the chicken coop.Compared with the whole closed culture mode,the semi-closed culture mold produced eggs and eggs.During the normal temperature storage,the growth rate of the eggs on the egg shell was significantly higher than that of the whole closed culture model.The eggshell surface of the eggs produced in the two kinds of breeding patterns showed multiple drug resistance,but closed Type egg shell eggs on the surface of E.coli resistance is relatively light,the advantages of different serotypes.