9) Trophoblast external to barrier
There is no extravillous trophoblast or infiltration of the endometrium by fetal cells.
10) Endometrium
No true decidua is being formed.
11) Various features
The endometrium beneath the implanted cotyledon is not infiltrated by trophoblast and appears histologically fibrous.
12) Endocrinology
No studies have been performed. The fetal ovaries were very small and unstimulated.
13) Genetics
The Cuvier's gazelle has 32 chromosomes in females, and 33 chromosomes in males. This is due to the Robertsonian translocation of the X-chromosome to an autosome (Kumamoto & Bogart, 1984). These authors also found minor banding variations among several animals. Vassart et al. (1995) further delineated the cytogenetic arrangements of gazelle chromosomes, using the caprine banded karyotypes as the presumed ancestral form. These two groups of authors both found the karyotypes to be similar to that of Gazella leptoceros, despite their significantly different phenotypes. Hybrids are unknown.
Inbreeding ("depression"), however, may be a problem in this species. Roldan et al. (1998) and Gomendio et al. (2000) studied the ejaculatory semen quality of this species and that of the less endangered G. dama. Their findings suggested that, while the quality of Cuvier's gazelle semen was inferior, it had not yet reached devastating proportions.
14) Immunology
No studies are known to me.
15) Pathological features
This animal died from peritonitis due to intestinal perforation. It also had gastric ulcers and massive whipworm infestation. Toxoplasmosis has been reported by Stiglmair-Herb (1987), and a variety of helminthes were found in animals captive in Spain (Ortiz et al., 2001a). These authors worked with a large number of animals (58) and experimented with various anthelminthic regimes (Ortiz et al., 2001b).
16) Physiologic data
No studies are known to me other than the collection of hematologic and biochemical data by Casado et al. (1991).
17) Other resources
Cell lines of numerous animals are available from CRES at San Diego Zoo by contacting Dr. Oliver Ryder at: oryder@ucsd.edu.
18) Other remarks - What additional Information is needed?
Term placentas, their weights, and dimensions are still unknown. It would also be of interest to know if hybridization with slender-horned gazelles occurs and whether they would be fertile.
Acknowledgement
The animal photographs in this chapter come from the Zoological Society of San Diego. I appreciate also very much the help of the pathologists at the San Diego Zoo.
References
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