The role of various agents in chicken amyloid arthropathy

The results of an inventory of field cases of amyloid arthropathy in chicke ns and of routine post-mortem recordings over a two years period are descri bed Studies were also performed to evaluate the amyloidogenic potential of arthrotropic bacterial species (Staphylococcus aureus, Escherichia coli and Salmonella enteritidis) isolated from chickens as well as several Enteroco ccus faecalis isolates compared to the amyloidogenic E. faecalis isolate (p reviously isolated from amyloidotic joints). As chicken anemia virus was al so isolated from amyloidotic joints of field cases, it was also screened fo r its amyloidogenic potential. In another experiment, Mycoplasma synoviae, inactivated E. faecalis isolate 6085.94, Freund's adjuvant and an arthrotro pic reovirus field isolate were also screened for amyloidogenicity by intra -articular injection. These studies showed that the ability to elicit extensive amyloid arthropat hy is reserved primarily to E. faecalis, but that this property is not comm on to every E. faecalis isolate. Intra-articular application of complete Fr eund's adjuvant led to the formation of extensive joint amyloid deposits. O f the other micro-organisms studied S. aureus, S. enteritidis and E. coli w ere also able to cause joint amyloidosis,but in very small amounts. Inactiv ated E. faecalis, chicken anemia virus and reovirus did not cause amyloid a rthropathy after intra-articular inoculation. This study is consistent with results of the analyses of previous field cas es and of the induction of amyloid arthropathy in chickens, suggesting a co nsiderable role for E. faecalis in this clinical-pathological entity. Finally, strain typing by analysis of chromosomal DNA restriction endonucle ase digests by pulsed-field gel electrophoresis (PFGE) of amyloidogenic, no n-amyloidogenic, amyloid-associated and other E, faecalis isolates from var ious origins showed that all amyloidogenic and amyloid-associated E. faecal is isolates had similar restriction digests, suggesting clonal spread.