ALLERGIC RHINITIS IN A HERD OF CATTLE

Allergic rhinitis was identified in a herd of Hereford cattle, Affecte d cattle had clinical signs of rhinitis (eg, nasal discharge, sneezing , nasal irritation, and nasal pruritus) and multiple small proliferati ve lesions in the nasal passages. Eosinophils were the predominant cel l type in nasal discharges, and histologic examination of nasal mucosa biopsy specimens revealed chronic proliferative eosinophilic rhinitis . Results of CBC were normal; plasma fibrinogen concentrations were wi thin reference limits. Results of intradermal allergen sensitivity tes ting and an ELISA for allergen-specific IgE only suggested an exaggera ted IgE-mediated response to environmental allergens. Allergen-specifi c IgG may have acted as a competitive blocking antibody and limited cl inical signs of disease in some cattle.