Granulomatous proventriculitis associated with Microtetrameres (Nematoda: Tetrameridae) infection in the Cattle egret (Bubulcus ibis) from Rio de Janeiro, Brazil

Host-parasite interactions can change and be rediscovered, exhibiting shifts or new pathogenies, which are mainly described for those poorly-studied species. The infection by Microtetrameres was firstly described in Bubulcus ibis in 1991, in which the reports of this infection have been related to mild lesions and low pathogenicity, mainly resulting in proventricular gland atrophy. In the two cases described in the present work, we report severe lesions, represented by serious inflammation associated with proventricular gland disruption. This fact may favour opportunistic pathogens, thus highlighting the importance of Microtetrameres infections in B. ibis.