Browsing by Author "Mouton, Marnel"

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    Fungi associated with the skin of a southern right whale (Eubalaena australis) from South Africa
    (Taylor & Francis group, 2010-09) Reeb, Desray; Best, Peter; Botha, Alfred; Cloete, Karen J.; Thornton, Meredith; Mouton, Marnel
    Cutaneous fungi are known to affect parts of the outermost skin layers of mammals, including the epidermis, stratum spinosum and stratum corneum, as well as mucocutaneous membranes, genitalia or external ears. Relatively little is known about fungal infections of Mysticete cetaceans and studies are needed to determine the fungal diversity associated with these marine mammals. This case report was aimed at identifying the fungi associated with the skin of a diseased neonatal southern right whale (Eubalaena australis) found stranded in the Western Cape Province of South Africa. Initial physical examination on site revealed hyperplasia of the follicular and epidermal epithelium. Preliminary examination of skin biopsies using scanning electron microscopy indicated that the skin was colonized by fungal hyphae. Isolation methods yielded a number of fungal isolates, which were identified using standard morphology and rDNA sequence data. These analyses confirmed colonization of the cutaneous layers by species belonging to the genera Fusarium, Chaetomium and Penicillium. Moreover, all isolates were capable of degrading keratin, indicating that skin may act as a natural substrate for these fungi. This study is the first report of the association of these fungi with southern right whale skin.
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    Scientific discourse : can our first-year students express themselves in science?
    (University of Valencia, 2020) Mouton, Marnel; Rootman-Le Grange, Ilse
    Scientific discourse is a specialized, semantically dense language used to formulate clear, objective arguments around experimental results. However, science classrooms are practically void of scientific argumentation and this important skill is rarely modelled or developed in these spaces. Yet, students are expected to engage with complex disciplinary texts and then demonstrate their mastery of scientific subject matter using appropriate scientific discourse. Students find this extremely challenging and many are implicitly excluded from successful engagement with the subject. The aim of our study was the assessment and development of first-year biology students’ scientific discourse skills through collaborative pedagogy, to make aspects of biology discourse explicit to all students. We drew on Legitimation Code Theory’s concept of semantic density, which considers complexity of meaning, to design a learning opportunity and then analyzed selections of students’ summative assessments. Results showed profound variation in the proficiency of the students’ scientific vocabulary and language functions, and the discourse of the school and first-year biology textbooks. We therefore argue for science pedagogy that would allow students time and opportunities to mindfully engage with complex disciplinary text and then demonstrate their mastery of their learning using appropriate scientific discourse.
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    Yeast infection in a beached southern right whale (Eubalaena australis) neonate
    (Wildlife Disease Association, 2009) Mouton, Marnel; Reeb, Desray; Botha, Alfred; Best, Peter
    A female southern right whale (Eubalaena australis) neonate was found stranded on the Western Cape coast of southern Africa. Skin samples were taken the same day from three different locations on the animal’s body and stored at 220 C. Isolation through repetitive culture of these skin sections yielded a single yeast species, Candida zeylanoides. Total genomic DNA also was isolated directly from skin samples. Polymerase chain reaction analysis of the internal transcribed spacer region of the fungal ribosomal gene cluster revealed the presence of Filobasidiella neoformans var. neoformans, the teleomorphic state of Cryptococcus neoformans. Fungal infections in cetaceans seem to be limited when compared to infections caused by bacteria, viruses and parasites. However, Candida species appear to be the most common type of fungal infection associated with cetaceans. To our knowledge this is the first report of a C. zeylanoides infection in a mysticete, as well as the first report of a dual infection involving two opportunistic pathogenic yeast species in a cetacean.