deoxycholic-acid and Swine-Diseases

We have characterized antigens from Actinobacillus (A.) pleuropneumoniae grown under iron restriction with respect to their immunogenic and protective potential. Antigens were the cell-free culture supernatants (CFS) obtained after treatment of A. pleuropneumoniae broth cultures with sodium deoxycholate. Using the iron-repressible transferrin-binding lipoprotein TbpB and the constitutively expressed outer membrane lipoprotein OmlA as markers, we have shown that the detergent extraction enriched the CFS with lipoproteins from the outer membrane (OM). Extractions with 0.05% of sodium deoxycholate increased the lipoprotein contents in the CFS, but did not affect the integrity of the OM. This was demonstrated by the absence of the iron-repressible integral OM transferrin-binding protein TbpA. Furthermore, the absence of periplasmic and cytoplasmic proteins in CFS after extraction was determined in immunoblot analyses with anti-bacterial alkaline phosphatase and anti-Hsp60 antisera, demonstrating that there was no rupture of the OMs or the plasma membranes due to the extraction procedure. Antigen preparations from A. pleuropneumoniae serotype 2 and 9 grown under iron restrictive conditions were combined, emulsified, and tested for their ability to confer protection in pigs. Pigs immunized with CFS from sodium deoxycholate extracted cultures developed a strong antibody response and, upon challenge with A. pleuropneumoniae serotype 2, the immunized pigs showed no or only mild clinical signs of disease and had a significantly lower degree of lung damage than the control pigs.

Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Bacterial Vaccines; Deoxycholic Acid; Detergents; Iron; Male; Pneumonia, Bacterial; Swine; Swine Diseases; Vaccines, Subunit

Injection of verotoxin 2e together with sodium deoxycholate, which increases intestinal permeability to macromolecules, into the intestine of pigs resulted in fluid accumulation, intestinal damage, and signs and lesions of edema disease. Intragastric administration of verotoxin 2e to newborn piglets, who normally absorb protein nonspecifically, resulted in systemic verotoxemia. These results suggest that development of natural edema disease requires a state of increased intestinal permeability.

Topics: Animals; Animals, Newborn; Bacterial Toxins; Deoxycholic Acid; Edema; Enterotoxins; Female; Intestinal Absorption; Shiga Toxin 2; Swine; Swine Diseases

Pathogenic and non-pathogenic spirochetes isolated from the intestines of pigs were examined by electron microscopy using the negative staining and ultrathin sectioning techniques. Morphological differences were observed among cells of different strains. The cells differed in length as well as in width and in the number of flagella inserted at each end. In addition, the cells from different strains also varied in their resistance to the action of the detergents, Teepol and sodium deoxycholate. Three of the strains studied contained weakly haemolytic spirochetes, two of which differed markedly in their morphology from the cells of the other strains. These spirochetes had fewer flagella inserted at each end than those from other isolates and showed a distinct lattice-like substructure covering the ends of the cells. The spirochetes examined were found to be morphologically more similar to those of the genus Borrelia than to those of the genus Treponema but were clearly different from the cells of both of these genera. The taxonomic implications of the observations are discussed in brief.

Topics: Animals; Deoxycholic Acid; Detergents; Dysentery; Fatty Alcohols; Flagella; Intestines; Microscopy, Electron; Spirochaetales; Spirochaetales Infections; Swine; Swine Diseases

Freeze-thaw lysates prepared from strains of Escherichia coli belonging to serogroups O138, O139, and O141 contained a principle (edema disease principle) which induced edema disease in swine. All freeze-thaw lysates contained endotoxic activity that tended to obscure the edema disease syndrome and methods were developed to reduce such activity. Freeze-thaw lysates prepared from E. coli O139 induced the most characteristic edema disease syndrome. Partially purified edema disease principle prepared from O139 freeze-thaw lysates by sequential precipitation with ammonium sulphate and streptomycin sulphate had increased specific activity with markedly reduced endotoxic activity. This material was insoluble at acidic pH but readily soluble at alkaline pH. The effective molecular weight of edema disease principle, based on retention and filtration properties of diaflo membranes, appeared to be greater than 50,000 and less than 100,000. The biological activity of edema disease principle was thermolabile. Sodium deoxycholate treatment of edema disease principle further reduced endotoxic activity. A thermolabile, ammonium sulphate precipitable material was prepared from E. coli O139 that induced a predictable syndrome which resembled edema disease clinically and pathologically following intravenous inoculation in pigs.

Topics: Ammonium Sulfate; Animals; Chemical Precipitation; Culture Media; Deoxycholic Acid; Edema Disease of Swine; Endotoxins; Escherichia coli; Escherichia coli Infections; Female; Injections, Intravenous; Male; Molecular Weight; Shock, Septic; Streptomycin; Swine; Swine Diseases; Ultrafiltration