| Autor: |
Avdeev M; Department of Evolutionary and Environmental Biology, University of Haifa, Mount Carmel, Haifa 3498838, Israel, michalalmoznino@gmail.com., Tal S; Department of Animal Science, Tel Hai College, Upper Galilee 1220800, Israel.; Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot 76100, Israel., Fishman R; Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 529002, Israel., Vortman Y; Department of Animal Science, Tel Hai College, Upper Galilee 1220800, Israel., Shanas U; Department of Evolutionary and Environmental Biology, University of Haifa, Mount Carmel, Haifa 3498838, Israel.; Department of Biology and Environment, University of Haifa-Oranim, Oranim, Tivon 3600600, Israel. |
| Abstrakt: |
The nutria ( Myocastor coypus ) is a globally widespread invasive species. Attempts to eradicate nutria by shooting, poisoning, and trapping have been mostly unsuccessful, leading to calls for the development of new control methods. The compound 4-vinylcyclohexene diepoxide (VCD) is known to cause follicular atresia in mammals and may control conception when administered orally. It was hypothesized that VCD administered PO will cause follicular destruction in female nutria. VCD (250 mg/kg PO) was administered or coconut oil, as a control, to five nutria females each for 12 d. Sixty days following VCD exposure, males were introduced to the females. Over the following 7 mon, the effect of VCD on nutria fertility was assessed by conducting ultrasound monitoring to determine pregnancy status and measuring blood serum progesterone and estradiol levels. Finally, after performing ovariectomies, viable follicles were counted on histologic ovarian cortical sections. It was found that the female estrous cycles became synchronized, suggesting a Whitten effect in this species. Also, an increase in the females' serum progesterone levels following the introduction of males occurred, suggesting a male presence effect. Orally administered doses of 250 mg/kg VCD for 12 d had no significant effect on nutria pregnancy rates or on the number of follicles in the ovaries examined. Further studies, using a higher dose or longer administration period, are necessary to conclude whether orally administered VCD can be used as a contraceptive agent for nutria. |
