Gross Anatomy of Pampas Deer (Ozotoceros bezoarticus, Linnaeus 1758) Mouth and Pharynx

Anat Histol Embryol. 2017 Apr;46(2):195-203. doi: 10.1111/ahe.12257. Epub 2016 Oct 17.

Abstract

The aims of this study were to describe the anatomy of the mouth and pharynx of the pampas deer, and to consider its evolutionary feeding niche according to those characteristics. Gross dissections of the mouth and pharynx were performed in 15 animals, 10 adult females and five young animals under 1 year (three males and two females), all dead by causes unrelated to this anatomical region. The upper lip entered in the constitution of a pigmented nasolabial plane. The masseter muscles weighed 43.8 ± 3.5 g and represented 0.23% of body weight, which corresponds to ruminants of feeders intermediate to grazers and browsers. Parotid glands represented 0.08% of the body weight, characteristic that also categorize the pampas deer as belonging to the intermediate feeding group. The dental formula was the same of the domestic ruminants. The upper incisors and canines were absent, and instead of them, there was a dental pad (Pulvinus dentalis). The upper canine teeth were present only in the deciduous dentition. The existence of a brachydont dentition turns Ozotoceros very vulnerable to continuous use as there is no compensatory teeth growth. The particular anatomy of the mouth and lips of this animal was adapted to a very selective feeding, taking highly nutritious sprouts beyond plant category. In conclusion and in addition to previous studies of anatomy of the digestive organs in this species, pampas deer may be categorized as belonging to the intermediate type of feeding.

MeSH terms

  • Animals
  • Biological Evolution
  • Deer / anatomy & histology*
  • Dissection / veterinary*
  • Feeding Behavior / physiology*
  • Female
  • Male
  • Mouth / anatomy & histology*
  • Pharynx / anatomy & histology*
  • Tooth / anatomy & histology