ClinQuiz: Equine parasites, answer 2C
1) C — Incorrect.
Parascaris equorum is not transmitted from mares to foals transplacentally or transmammarily. Rather, foals acquire infection from ingesting eggs containing infective larvae that are present in an environment previously contaminated with feces from other infected foals.9 The eggs are hardy, surviving in the environment from year to year. Once patent infections have established, foals may reinfect themselves with additional ascarids even in the absence of a previously contaminated environment.10