1) General Zoological Data
This gazelle was named in honor of a great German physician upon his 50th anniversary of obtaining the medical degree. Cretzschmar (1826) depicted that animal as being quite dark brown; it is reproduced here from the first picture. In the review of "Nanger" gazelles, however, Lange (1971) described the animal as having a light-colored back. Moreover, he suggested that a number of subspecies exist, largely differentiated by horn types. He reviewed skulls and living specimens of this species and compared them with Dama and Grant gazelles. Soemmerring's gazelle is the smallest of these species and is one of the "Nanger" (naguer) gazelles, or "Spiegelgazellen" (because of the white rear patch. The denominated specimen was said to have originated in Somalia. Most or at least many animals now kept in zoos come from Khartoum, but who it is that makes the decision for the denomination "Soemmerring" of any given animal is unknown. This is even more dubious when their chromosomes and varied phenotypes are studied. It would appear that there is a mixture of these animals in captivity and few if any are truly Soemmerring's gazelles as originally described. This hybridization of related species with, however, different chromosome numbers, is perhaps also the reason for their frequently poor reproductive performance in captivity.
Longevity of this species was given as being 15 years 6 months (Jones, 1993). The behavior of this species was studied in detail by Walther (1964).
General Gestational Data
Mentis (1972) reviewed many characteristics of ungulate gestations. The gestational period of Soemmerring's gazelles is given as "a few days over 7 months" from observations in the Giza Zoological Garden. Singletons are the rule. The neonate observed by us weighed 2,600 g and the placenta was 175 g.
There are no reports on early implantation and the mode of implantation. In general it can be expected that all reproductive aspects are very similar to those of the Mhorr gazelle. They have there been summarized in considerable detail and the reader is invited to check details there as well.
General Characterization of the Placenta
Details of fetal/maternal barrier
The long, slender villi are covered by simple, and mostly single-nucleated trophoblast and abut maternal endometrial epithelium (which is not present in this specimen, of course). There is also too much autolysis in this specimen to make really detailed observations. Nevertheless, typical binucleate cells are present, as expected, but they are not abundant. The fetal capillaries impinge deeply upon the trophoblast. There is virtually no yellow pigmentation of trophoblast in the specimen for study.
There are two arteries and two veins. In the center is a large allantoic duct. The cord is not spiraled and was 9 cm long in this specimen. Characteristically, one pair of vessels passes to one horn, the other pair to the other horn. In addition to the paired large blood vessels, there are numerous smaller blood vessels, especially around the allantoic duct. It is lined with flat urothelium and contained some debris.
No details are known.
Trophoblast external to barrier
No details have been published.
Other remarks - What additional Information is needed?
Cretzschmar, P.J.: Atlas zu den Reisen im nördlichen Afrika von Eduard Rüppell. Säugethiere. Brönner, Frankfurt, 1826.
Iori, A. and Lanfranchi, P.: Contribution to the knowledge of helminthofauna of wild mammals of Somalia. Parassitologia 38:511-515, 1996.
Jones, M.L.: Longevity of ungulates in captivity. Intern. Zoo Yearbk. 32:159-169, 1993.
Lange, J.: Ein Beitrag zur systematischen Stellung der Spiegelgazellen (Genus Gazella Blainville, 1816 Subgenus Nanger Lataste, 1885). Z. Säugetierk. 36:1-18, 1971.
Mentis, M.T.: A review of some life history features of the large herbivores of Africa. The Lammergeyer 16:1-89, 1972.
Olsen, J.H. and Jones, H.: Hematologic and serum chemistry values for captive Soemmering's gazelle (Gazella soemmerringi) immobilization consultation. J. Zoo Anim. Med. 15:5-7, 1984.
Pickard, A.R., Abaigar, T., Green, D.I., Holt, W.V. and Cano, M.: Hormonal characterization of the reproductive cycle and pregnancy in the female Mohor gazelle (Gazella dama mhorr). Reproduction 122:571-580, 2001.
Vassart, M., Séguéla, A. and Hayes, H.: Chromosomal evolution in gazelles. J. Hered. 86:216-227, 1995.
Walther, F.: Zum Paarungsverhalten der Sömmeringgazelle (Gazella soemmerringi Cretzschmar 1926). Zool. Garten 29:145-160, 1964.
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