Fungal Flora of Normal Eyes in Healthy Newborn Foals Living in the Same Stud Farm in Italy

Abstract 

The aim of this study was to assess the presence of fungal flora in conjunctiva of newborn foals revealed by means of repeated culture examinations and to compare prevalences in foals and their mares. Fifty-four healthy foals and their mothers were used. Ocular samples were collected from foals immediately after parturition (D0), and at days 2 (D2), 7 (D7), 14 (D14), and 28 (D28), and at D0 from mares. Samples were seeded onto Sabouroud dextrose agar and malt extract agar, incubated at 25°C and examined daily over a 10-day period. Twenty-two of 54 foals were positive for conjunctival fungi at D0, 13 of 54 at D2, 16 of 54 at D7, 19 of 54 at D14, and 13 of 54 at D28. The most frequently isolated fungi were Penicillium species and Aspergillus versicolor. Colony-forming units ranged from 1 to 5. One of 54 foals yielded the same fungus more than two times consecutively; 23 of 54 mares were positive for conjunctival fungi, and the most frequently recovered were Penicillium species, Aspergillus species, and Saccharomyces cerevisiae. Significant differences among prevalences, both at different sampling times in foals, and between mares and foals at D0, were not observed. A fungal contamination of conjunctival fornix in foals at birth and during their first month of life was reported. Fungal isolation in foals at D0 might be explained by the presence of fungal contamination within mares' genitalia, whereas positive cultures during the first month of life probably represent transient seeding from the environment. Only once was the same fungus isolated from the same foal more than two times consecutively.

Keywords: Foal, Conjunctiva, Fungi, Yeast, Colonization