规模化养猪场仔猪黄痢病原菌优势血清型检测及其致病性试验

SEROTYPE IDENTIFICATION AND PATHOGENICITY TEST OF THE PATHOGENIC BACTERIA LSOLATED FROM PIGLIT'S YELLOW DYSENTERY IN LARGE-SCALE PIG FARMS

从临沂市规模化养猪场仔猪黄痢病例中分离病原菌、检测其优势血清型,并经动物致病性试验探讨其优势血清型菌株的致病能力,为临床选用疫苗提供血清型依据,并为灭活苗的制备及药敏试验提供菌株。对临沂市不同区域的23个规模化养猪场的112份疑似仔猪黄痢病例进行了细菌分离,对分离到的致病性大肠杆菌进行了生化试验、毒力试验、血清学鉴定,分析出其优势血清型;取三日龄仔猪进行了优势血清型菌株致病性试验。112份病料中分离出了101株致病性大肠杆菌,分离率为90.2%;不同区域猪场流行的血清型有较大差异,在101个分离株中,7株未能定型、4株自凝,其余90株能定O型血清型,这些定型菌株分布在11个血清型中,其中优势血清型为O8,O54,O115,O149,这四种血清型共占定型菌株的56.7%。上述四种优势血清型的发病率均为100%,死亡率分别是100%、75%、100%、100%,致病率和致死率与对照组相比差异显著(P>0.05)。目前临沂市规模化养猪场仔猪黄痢病原菌的O型血清型分布在11个血清型中,其中优势血清型为O8,O54,O115,O149。四种优势血清型的发病率和死亡率均较高。

In this experiment,in order to select vaccine for clinic and provide reference for preventing and curing,the pathogenic bacteria was isolated from piglet sickened yellow dysentery in large-scale pig farms in Linyi.Escherichia.coli was separated from 112 samples of suspicious yellow scour of piglets in 23 scale farms in different areas of Linyi,biochemical test and virulence test were carried out,so did pathogenic test,serotype identification and animal pathogenicity test.[Results]（1）101 strains of Escherichia.coli were separated from 112 samples,account for 90.2%;There were much difference among different farms.In all the separated strains,7 strains were not identified and 4 strains agglutinated,therefore only 90 strains were identified with the serum of O,which distributing in 11 serotype;O8,O54,O115 and O149 were advantaged serotypes,which accounted for 56.7% of all identified bacteria;Animal pathogenicity test indicated that four prevalent serotypes had pathopoiesis rate 100%;respective lethality 100%,75%,100% and 100%.Mkdly differented from control group.At present,O-serotype of yellow scour of newborn piglets in Linyi scale pig farms distributed to 11 serotypes,O8,O54,O115 and O149 were advantaged serotypes;four prevalent serotypes had altus pathopoiesis rate and lethality.