Morphological Features of the Luminal Surface of the Magnum in the Sexually Immature Ostrich (Struthio camelus)

Abstract

Summary Observations were made, using scanning electron microscopy, of the surface features of the magnum in the immature ostrich during periods of ovarian inactivity, activity and regression. In birds with inactive ovaries the luminal surface of the magnum was lined with non-ciliated cells, which were densely covered by microvilli. In contrast, the magnum in birds with active ovaries was composed of ciliated and non-ciliated cells. The distribution of ciliated cells was not uniform, with clumps of cilia occurring next to non-ciliated areas. Samples collected from birds with regressing ovaries, during periods of decreasing daylength, revealed that the magnum was undergoing involution. The deciliation of ciliated cells and the presence of short microvilli on non-ciliated cells characterized magnal regression. These results suggest that ovarian activity and changes in daylength have a profound effect on the surface features of the magnum in the immature ostrich.

Light, Scanning and Transmission Electron Microscopical Study on the Oviduct of the Ostrich (Struthio camelus)

“…In the available literature, only few studies on the morphology and ultrastructure of the ostrich oviduct were found ( Muwazi et al,1982, Hicks-Allderdge, 1998, Madekurozwa, 2005and Sharaf , 2005. The present work aims to study the histological, histochemical structure as well as the ultrastructure of the oviduct of ostrich.…”

An Immunohistochemical Study of the Oviduct in the Domestic Fowl (Gallus domesticus)

“…The oviduct in birds is composed of the infundibulum, magnum, isthmus, tubular shell gland, shell gland pouch and vagina (Solomon, ). Extensive histological and ultrastructural studies have been conducted on the various regions of the oviduct in several avian species (Fertuck and Newstead, ; Wyburn et al., ; Draper et al., ; Madekurozwa, , ).…”

Wild ostrich (Struthio camelus australis) reproduction in Orbata, a nature reserve in Tunisia

“…Compared with the countries of the Northern hemisphere, the ostrich laying season begins earlier in Tunisia (essentially in January). According to the studies of Degen et al (1994); Madekurozwa (2002aMadekurozwa ( , b, 2004Madekurozwa ( , 2005Madekurozwa ( , 2007, Madekurozwa et al (2002), Madekurozwa and Kimaro (2006) and Bronneberg et al (2007), the beginning of an ostrich's sexual activity takes place mainly during increasing photoperiods. Our results showed the same phenomenon; indeed, in 94.2% of nests the laying began during increasing photoperiods.…”