A study on the vertical transmission of arthropathic and amyloidogenic Enterococcus faecalis

Ten brown layer parent hens were injected intravenously with arthropathic a nd amyloidogenic Enterococcus faecalis at 27 weeks of age to assess its ver tical transmission during the subsequent 6-week production period. All inoc ulated hens developed chronic bacteraemia and arthritis, four died due to s epticaemia and two of the remaining six showed amyloid arthropathy. The egg production was maintained at a lower level than the controls. Of eggs coll ected during the first 2 weeks after inoculation, E. faecalis was re-isolat ed from the yolk sac of 76% (13/17) of infertile eggs and dead embryos dete cted at the 18-day candling, and 100% (6/6) of non-hatching eggs, and from arthritic joints of 3% (2/66) offspring chicks of the same batch, although the latter did not develop joint amyloidosis by 8 weeks of age. E. faecalis was also re-isolated from ovary and oviduct of parent birds that died due to septicaemia. The E. faecalis organisms re-isolated from blood, ovaries a nd joints of diseased parent stock, yolk sac of infertile eggs and dead emb ryos detected at the 18-day candling, and non-hatching eggs, as well as org ans and joints of offspring, had the same pulsed-field gel electrophoresis patterns as the E. faecalis isolate used to infect the parent birds. These findings indicate that vertical transmission of arthropathic and amyloidoge nic E. faecalis may occur on a small scale.