the aim of the present study was to evaluate the presence anti- e. coli, -rotavirus and -coronavirus, in calves' sera. a total of 184 calves under 1 month of age (84 diarrheic & 100 normal) was studied. serological tests including: direct elisa for detection of anti-k99 e. coli, - rotavirus and - coronavirus and tube agglutination test for detection anti-o157 e. coli, antibodies were used....

BACKGROUND: BACKGROUND: Enterotoxigenic Escherichia coli (ETEC) is the main causative agents of neonatal calf diarrhea. Passive transfer of antibodies that is derived from the dams of the calves through their colostrum plays an important role in disease prevention. OBJECTIVES: To determine the presence of natural specific antibodies against K99 antigen in dam’s serum and colostrum as well as in...

The erythrocyte receptor for Escherichia coli K99 fimbrial adhesin was isolated from equine erythrocytes and characterized as Neu5Gc-alpha(2----3)-Galp-beta(1----4)-GLcp-beta(1----1)-Ceramide. This glycolipid acted as the receptor for K99 by four different experimental approaches: inhibition of equine erythrocyte hemagglutination by preincubation of K99-positive bacteria or purified K99 fimbria...

The production of the K99 antigen by enterotoxigenic Escherichia coli strains with various O antigens was investigated by means of slide agglutination tests, enzyme-linked immunosorbent assays, and hydrophobic interaction chromatography. The extent of K99 production appeared to be dependent on the nutrient medium, as well as on the incubation temperature. Minimal salt medium with glucose and se...

Single-chain antibodies (scFv) are small, recombinant proteins in which variable domains from immunoglobulin heavy and light chains are physically linked with a flexible peptide. They are monovalent and lack the heavy chain constant domins for activation of complement and binding to cellular receptors. However scFvs can possess biological activity by binding to and inhibiting the action of thei...

در این بررسی از کیت تجارتی الایزای رقابتی جهت اندازه گیری پادتن های ضد E. coli K99، روتاویروس و کورناویروس در 240 نمونه آغوز اخذ شده از گاوان هلشتاین نژاد شیری در یک واحد گاوداری جنوب تهران استفاده گردید. ملاک مثبت شدن در الایزای رقابتی به این ترتیب بود که نمونه های با درصد جلوگیری 20

The aim of this study was to optimize the dose regimens of enrofloxacin to reduce the development of fluoroquinolone resistance in Escherichia coli (E.coli) using pharmacokinetic/pharmacodynamic (PK/PD) modeling approach. The single dose (2.5 mg/kg body weight) of enrofloxacin was administered intramuscularly (IM) to the healthy pigs. Using cannulation, the pharmacokinetic properties, including...

A spontaneously occurring field isolate of enterotoxigenic Escherichia coli that was genotypically K99+ but phenotypically K99- was analyzed for the reason that it did not express K99. The defect, which was cis active, was located within an area 5' to the first gene required for K99 biogenesis and was the result of the deletion of a single base pair.

It was found that K99 pili from enterotoxigenic Escherichia coli (of bovine origin) could be extracted by treatment with 3M-KSCN solution. The K99 pili were purified by preparative isoelectric focusing to apparent homogeneity as judged by the presence of a single band on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis; the molecular weight of this component was calculated to be 12 60...

background: k99 pilus antigen is one of the major adherence factors found on enterotoxigenic escherichia coli (etec) of neonatal calves. it causes severe diarrhea in newborn calves via the production of heat-stable enterotoxin (sta).with increasing concern over the spread of antimicrobial resistance, the development of alternative to conventional antibiotics such as colicin is urgently needed. ...