Faculty of Veterinary Science
Department of Veterinary Anatomy and Physiology
Selected Highlights from Research Findings
South Africa has a vibrant ostrich industry, which has made a major contribution to the economy. Recently, a second economically important ratite, the emu, has been introduced to South Africa. Emus are being reared in South Africa mainly for their subcutaneous fat, from which emu oil is extracted.
The extraction and processing of emu oil is a growing industry in South Africa. It is widely used to alleviate the symptoms of arthritis in humans. Although both ratites, the ostrich and emu have different breeding seasons. The ostrich is generally a long day breeder, while the emu breeds during short day lengths. A common feature of both is the low fertility rate in captivity.
Research has been conducted on the reproductive biology of both immature and mature female ostriches in order to provide basic information, which may then be used to elucidate the reasons for low fertility in these birds. The project has now been expanded to include the female emu.
Immunohistochemical studies on the distribution of intermediate filaments in the ovaries of the emu and ostrich have highlighted similarities and differences between the two. In both smooth muscle actin immunoreactive fibroblast-like cells were demonstrated in the theca externa of vitellogenic follicles.
These cells are most likely involved in the ovulatory process, as well as in the infolding of the follicular wall during atresia. In the ostrich smooth muscle actin and desmin immunoreactive fibroblast-like cells were prominent features of atretic vitellogenic follicles.
Although the stages of atresia in the emu appear similar to those of the ostrich, smooth muscle actin and desmin immunoreactive cells were not observed in the emu. Instead atretic follicles in the emu were characterized by the presence of numerous melanocytes, the function and significance of which is unclear at present.
Information gained from this project on the morphology and stages of degeneration of ovarian follicles in the ostrich and emu establishes a baseline for researchers investigating ovarian dysfunction in ratites
Contact person: Dr M-CN Madekurozwa.
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