Feeding bacteria-free whole cell lysates of Escherichia coli to gnotobiotic pigs and the effects of giving antiserums
Kohler, E.M.; Cross, R.F.
American Journal of Veterinary Research 32(5): 739-748
1971
ISSN/ISBN: 0002-9645 PMID: 4932837 Document Number: 42960
Whole cell lysates (WCL) and broth supernatant filtrates (BF) were prepared from syncase broth cultures of ten enter pathogenic and three non-enter pathogenic strains of E. coil. The WCL and BF were administered intragastrically to unweaned pigs. The WCL from five enter pathogenic strains caused diarrhoea, dehydration and death. The BF from six enter pathogenic strains caused diarrhoea, but little dehydration and no deaths. Both BF and WCL of only one strain caused diarrhoea. A comparison was made between pigs given WCL and pigs given BF as to the differences in time of onset and duration of diarrhoea, and in the outcome. Clinical abnormalities were not detected following intragastric administration of WCL and BF of non-enter pathogenic strains. Differences in heat stability, pH stability, charcoal adsorbability and methanol solubility of WCL and BF enter toxins were observed. Diarrhoea, dehydration and frequently death occurred in pigs fed WCL of five of six enter pathogenic strains of E. coli. Serum from gnotobiotic pigs vaccinated with enterotoxic WCL, when fed to gnotobiotic pigs, had a specific protective effect which seemed to be directed against the diarrhoea-inducing component of enterotoxic WCL and to function in the lumen or near the surface of the mucosa of the intestine. In addition, there was a nonspecific interference with the diarrhoea-inducing activity of enterotoxic WCL when larger quantities of normal serum were fed. Formolized cultures of two non-enter pathogenic and four enter pathogenic strains of E. coil were used to vaccinate six ordinary pigs. Serum from these pigs protected gnotobiotic pigs from diarrhoea when 30 ml was given, but the effect may not have been specific.