Histological, Histochemical, and Ultrastructural Approach to the Ductus Deferens in Male Nile Monitor Lizard (Varanus niloticus).

The ductus deferens is a fundamental part of the male genital tract and the continuation of the epididymal duct. As a male secondary sex organ, the ductus deferens plays a crucial role in the nourishment, storage, and maturation of spermatozoa. Some studies have provided information about the ductus deferens structure in reptiles; however, the full description of the ductus deferens remains to be clarified. The current study aimed to describe the Nile monitor lizard (Varanus niloticus) ductus deferens from histological, histochemical, and ultrastructural perspectives. The results revealed that the ductus deferens is formed histologically from two main cell types: principal and basal. The principal cells were tall and filled with periodic acid Schiff (+)/alcian blue (−) cytoplasmic granules. The basal cells were found just above the basement membrane. By transmission electron microscopy, the principal cells exhibited typical protein-secreting cell features. Additionally, some intraepithelial cells, such as halo cells, undifferentiated mesenchymal cells, and agranular leukocytes, were identified. This study presents the first detailed description of the Varanus niloticus ductus deferens. Further immunohistochemical studies are required to explore the function(s) of the cellular components.

Impact of epidermal growth factor and/or ß-mercaptoethanol supplementations on the in vitro produced buffaloes' embryos.

The present study investigated the effects of epidermal growth factors (EGF) and/or ß-Mercaptoethanol (ßME) supplementations to oocyte maturation, fertilization, and culture media on the buffalo in vitro embryo production. The ovaries were collected and transferred within 2 h to the laboratory. The cumulus oocytes complexes were aspirated from 3 to 8 mm diameter follicles. Firstly, EGF; 0, 10, 20, or 50 ng/mL or ßME; 0, 25, 50, 100, or 200 µM were supplemented to the in vitro maturation (TCM-199), fertilization (IVF-TALP), or culture (IVC: SOF) media. Our results revealed that supplementing EGF (20 ng/mL) to the TCM-199, IVF-TALP, or SOF media could efficiently improve the growth rates and development of buffalos' embryos, while EGF (50 ng/mL) could stimulate the embryo production only after treatment of the IVF-TALP /or SOF media, but not the IVM medium. However, ßME was less efficient than EGF; it stimulated the growth rates of buffalo embryos when supplemented with the maturation and fertilization (IVF-TALP) media in a 50 µM concentration. Secondly, combined EGF (20 ng/mL) and ßME (50 µM) were supplemented to the maturation media as effective concentration. The combined treatment of EGF (20 ng/mL) and ßME (50 µM) showed no significant enhancing effect on the buffalo embryos compared to each alone. For future perspectives, further study is required to examine the effects of combined EGF and ßME on the maturation and fertilization of buffalo oocytes at different categories of age and seasonal localities.