*Similar to ''Ostertagia'', except L3 penetrate mucosa between gastric glands. Leads to hyperplastic nodular lesions (several cms diameter) and erosions where epithelium is lost. Not usually a primary pathogen in horses. | *Similar to ''Ostertagia'', except L3 penetrate mucosa between gastric glands. Leads to hyperplastic nodular lesions (several cms diameter) and erosions where epithelium is lost. Not usually a primary pathogen in horses. |