1. Laboratory of Immunology; Ghent University; Salisburylaan 133 B-9820 Merelbeke Belgium
2. Horse Hospital; Rue d'Autre-Eglise 49 B-1367 Huppaye Belgium
3. Department of Internal Medicine and Clinical Biology of Large Animals; Faculty of Veterinary Medicine; Ghent University; Salisburylaan 133 B-9820 Merelbeke Belgium