Conjunctivitis and ulcerative keratitis secondary to conjunctival plant foreign bodies in a herd of alpacas (Lama Pacos)

Abstract

To describe six cases of conjunctivitis and ulcerative keratitis secondary to plant foreign bodies from weed-contaminated grass hay which were lodged within the temporal conjunctival fornix in a herd of alpacas. A total of 21 alpacas from the same farm developed blepharospasm and mucopurulent ocular discharge. Six of the 21 were evaluated at the University of Tennessee College of Veterinary Medicine within a 2-week period. The six animals evaluated received an ophthalmic examination including slit-lamp biomicroscopy, fluorescein staining, and topical corneal anesthesia for foreign body removal when necessary. Six animals had conjunctivitis characterized by hyperemia and mucopurulent discharge. Five animals had superficial ulcerative keratitis with intense corneal neovascularization and edema. In all cases, the keratitis was located at the temporal limbus. Seven plant foreign bodies were observed and were removed following topical corneal anesthesia in five animals. The plant seeds were identified as three common weed species found in orchard grass hay. Complete resolution of all clinical signs was achieved with foreign body removal and medical therapy. Fan-shaped temporal corneal ulcers may signify the presence of conjunctival foreign bodies in alpacas. Plant foreign bodies should be considered in addition to ocular infection when multiple animals of a herd are affected as outbreaks may occur with weed-contaminated hay.