Gross anatomy of the male genital organs of the pampas deer (Ozotoceros bezoarticus, Linnaeus 1758)

Abstract

To describe the macroscopic anatomy of the genital organs of the male pampas deer (Ozotoceros bezoarticus), organs from ten animals found dead in a captive breeding station were dissected. The unpigmented scrotum was located in the inguinal region near the body, and was covered by the thighs. In the investments of the testicles the dartos tunic was greatly developed. The cremaster muscle was located dorsocaudal to the testicle, and was divided caudally into three bundles of fibers. The right testicle was significantly heavier than the left, and there was a positive relationship between body weight and the weight of both testicles. The tail of the epididymis, ventrally located, had a caudal portion attached to the caudal extremity of the testicles by the proper ligament of the testicles, and a portion elongated free caudally located. The deferent duct was located caudomedially to the corresponding testicle. The accessory genital glands were the ampullary glands, vesicular glands, and a small pars disseminata of the prostate. The penis was fibroelastic, without sigmoid flexure, with a thick albuginea. The retractor penis muscle was very long, and ended in the distal part of the penis near the rudimentary glans. The general disposition of the male genital organs of the pampas deer were similar to that of other ruminants, with some differences, such as size and location of the testicles, the absence of the sigmoid flexure of the penis, and fewer accessory genital glands.

Asymmetrical size and functionality of the pampas deer (Ozotoceros bezoarticus) testes: Right testis is bigger but left testis is more efficient in spermatogenesis

“…We confirmed and expanded previous findings from Pérez et al. () showing that the right testis is greater and heavier in adult males. The difference is even greater in adult than offspring males suggesting that the asymmetry increases during growth, but in any case, it is interesting to observe that differences in testis weight is already observed in recent born animals.…”

“…As in other studies on pampas deer anatomy (Pérez et al., ,b), the first non‐invasive approach was the study of the organs from dead animals. The study was performed with 23 deceased males from the ECFA.…”

“…Semicaptive breeding of animals that came from the O. b. arerunguaensis population started in 1981 at the Estación de Cría de Fauna Autóctona (ECFA, 34°3′ S, 55°1′ W; altitude: ~200 m), Pan de Azúcar, Maldonado, Uruguay. Pérez, Vazquez, and Ungerfeld (,b) recently described the reproductive anatomy in pampas deer males and females. In this species, the right ovary was thicker and tended to be greater than the left one in adult females; moreover, all the females that had corpus luteum had them in the right ovary (Pérez et al., ,b).…”

“…Pérez, Vazquez, and Ungerfeld (,b) recently described the reproductive anatomy in pampas deer males and females. In this species, the right ovary was thicker and tended to be greater than the left one in adult females; moreover, all the females that had corpus luteum had them in the right ovary (Pérez et al., ,b). In agreement, the right testis was significantly heavier and had greater volume than the left one (Pérez et al., ,b b).…”

Arterial Thoracic Vascularization in Some Deer Species: Pampas Deer (Ozotoceros bezoarticus), Brown Brocket Deer (Mazama gouazoubira) and Axis Deer (Axis axis)

“…The most of anatomical studies related to these deer species have focused on the urogenital apparatus (Halder et al., ; Willard and Randel, ; Pérez et al., ,b) and lower digestive system (Pérez et al., ; Pérez and Ungerfeld, ; Pérez and Vazquez, ). The detailed anatomy of the vascular system has not reported in these deer species until now.…”