The discovery of Besnoitia wallacei in Australia and the identification of a free-living intermediate host.

A cat fed free-living rats (Rattus norvegicus and Rattus rattus) passed coccidian oocysts 14 days after eating a R. norvegicus. These oocysts were morphologically similar to B. wallacei and rats and mice dosed orally and intraperitoneally with them developed Besnoitia cysts in various body tissues. This organism was shown to have an obligatory two-host cycle and it is considered to be B. wallacei. This represents the first recorded detection of B. wallacei in Australia and also the first record of a natural free-living intermediate host for B. wallacei.