Fusarium species isolated from post-hatchling loggerhead sea turtles (Caretta caretta) in South Africa

Abstract

Species in the Fusarium solani species complex are fast growing, environmental saprophytic fungi. Members of this genus are filamentous fungi with a wide geographical distribution. Fusarium keratoplasticum and F. falciforme have previously been isolated from sea turtle nests and have been associated with high egg mortality rates. Skin lesions were observed in a number of stranded, post-hatchling loggerhead sea turtles (Caretta caretta) in a rehabilitation facility in South Africa. Fungal hyphae were observed in epidermal scrapes of affected turtles and were isolated. The aim of this study was to characterise the Fusarium species that were isolated from these post-hatchling loggerhead sea turtles (Caretta caretta) that washed up on beaches along the South African coastline. Three gene regions were amplified and sequenced, namely the internal transcribed spacer region (ITS), a part of the nuclear large subunit (LSU), and part of the translation elongation factor 1 α (tef1) gene region. Molecular characteristics of strains isolated during this study showed high similarity with Fusarium isolates, which have previously been associated with high egg mortality rates in loggerhead sea turtles. This is the first record of F. keratoplasticum, F. falciforme and F. crassum isolated from stranded post-hatchling loggerhead sea turtles in South Africa.

Mycotic Diseases in Chelonians

“…Furthermore, in a recent extensive study on C. caretta with superficial lesions, F. keratoplasticum, Fusarium oxysporum, Fusarium brachygibbosum, along with haplotypes 9, 12, and 27 were identified, while animals with no disease were colonized by haplotypes 9 and 12 only [27]. Similarly, F. falciforme, F. keratoplasticum, and Fusarium crassum were isolated from stranded post-hatchling C. caretta in South Africa [44].…”

Fungal Diseases in Elasmobranchs and Their Possible Treatment with a Special Mention to Azole Antifungal Agents

“…Despite the absence of information in free-range fish, there are some reports of Fusarium spp. infections in wild marine animals [ 19 , 20 ]. Marine elasmobranchs are very susceptible to Fusarium solani mycosis and are responsible for the “Bonnethead shark disease” that appears in animals of the Sphyrna genus under human care.…”