Abomasum/metabolism; Helminth Proteins/metabolism; Sheep Diseases/metabolism; Trichostrongyloidea; Trichostrongyloidiasis/veterinary; Abomasum/drug effects; Abomasum/immunology; Adaptive Immunity; Animals; Anthelmintics/administration & dosage; Blotting, Western; Electrophoresis, Gel, Two-Dimensional; Galectins/genetics; Galectins/metabolism; Gastric Mucosa/drug effects; Gastric Mucosa/immunology; Gastric Mucosa/metabolism; Gene Expression Profiling; Gene Expression Regulation; Helminth Proteins/genetics; Proteomics; RNA, Messenger/metabolism; Serum Albumin/genetics; Serum Albumin/metabolism; Sheep; Sheep Diseases/drug therapy; Sheep Diseases/immunology; Sheep, Domestic; Thioredoxins/genetics; Thioredoxins/metabolism; Trichostrongyloidiasis/drug therapy; Trichostrongyloidiasis/immunology; Trichostrongyloidiasis/metabolism