An adult male (235 g) cock of the rock (Rupicola peruviana) was found on the floor of its exhibit at a zoo in Lima, Peru. The bird was depressed, with the right eye closed, and was easily captured. On physical exam, the right eye exhibited blepharospasms, hiphema, and conjunctivitis. The eye was cleaned with a saline solution, and two nematodes, approximately 1 cm in length, were found on the surface of the cornea. They were collected and stored in 70% alcohol. A corneal ulcer was diagnosed near the medial canthus with the help of fluorescein (Fluoresceina®, Laboratorio Love Sudamericana) drops. The bird was treated with one dose of ivermectin (Biomisil 0.1%®, Biomont, 0, 2 mg/kg IM), topical ciprofloxacin (Ciprolin®, Abeefe Bristol Myers Squibb, ophthalmic unguent) and an epithelium regenerator (Solcoceril®, Solco, ophthalmic gel) for 10 weeks. Four weeks later, the bird had gained weight (255 g) and the cornea showed a scar.
The two nematodes were clarified in lactophenol for evaluation and measurement, and were identified as members of the genus Thelazia, one of two genera of nematodes reported in the conjunctive mucosa of birds, the other being Oxyspirura.1 The primary characteristics used to differentiate the species of Thelazia are the lengths of spicules and other morphologic characteristics such as the number of pre- and post-anal papillae, and the first annulations on the anterior part of the body. The spicules were 1770 microns long and there were eight pairs of pre-anal papillae. The first annulations were observed 45 microns posterior to the buccal capsule, all of these being characteristics of T. anolabiata. The specimens were deposited in the U.S. National Parasite Collection at Beltsville, Maryland with the accession number 096991. There is some controversy about the classification of this nematode as a possible synonym of T. digitata. By rDNA, the species T. gulosa, T. rhodesi y T. skrjabini were differentiated, proposing this as a new tool for epidemiologic studies and taxonomic classification.3 This is apparently the first record of the cock of the rocks as a definitive host of T. anolabiata, and the first clinical description of thelaziosis in this host.
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2. De Oliveira Rodriguez H. On Thelazia anolabiata (Molin 1860) Railiett y Henry, 1910 (Nematoda, Thelazioidea)-A new host record and systematic considerations. Mem Inst Oswaldo Cruz. 1992;87(Suppl. 1):217–222.
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