Four cases of Streptococcus suis infection were diagnosed in psittacin
e birds and four others in zebrafinches, bullfinches, canaries and a d
uck. The main clinical and pathological manifestation was septicaemia
with multiple sudden deaths in nestlings, young and adults. Other case
s were solitary, with evidence for secondary involvement of S. suis. F
our serotypable strains all belonged to serotype 9.