Anatomy of the Mandibularand Maxillo-Facial Regionsof the Iranian NativeDonkeys and its Clinical ImplicationsduringRegional Anesthesia

The head is a very important region for animals. Also, donkey (equusasinus) is a member of the equidae family that is classified in the perissodactyla subgroup of ungulate group.Since there is a lack of comprehensive data on the clinical anatomy of the head region of the Iranian native donkeys and its clinical value during regional anesthesia; therefore, the present work was carried out.This study involved some morphometric parameters of the mandibles and upper jaws of ten Iranian native donkeys aged between 3-8-year- old without any apparent skeletal disorders. Then, a total of 17 head measurements and indices were recorded.The supraorbital foramina distance, infraorbital foramina distance, skull length, cranial length and nasal length of the Iranian native donkeys were 17.7 cm, 9.47 cm, 39.7 cm, 26.3 cm and 13.4 cm, respectively. In addition, the distances from facial crest to the infra-orbital canal and from the latter to the root of the alveolar tooth were 3.4 cm and 6.1 cm, respectively. The length and height of the mandibles of the Iranian native donkeys were 19.5 cm and 10.8 cm, respectively. Furthermore, the distances from the lateral alveolar root to mental foramen and from the mental foramen to caudal mandibular border were 11.15 cm and 8.35 cm, respectively. In the present study, the distances from mandibular foramen to the base of mandible as well as from caudal border of mandible to below of the mandibular foramen were 4.7 cm and 4.2 cm, respectively. Also, the distances from the base of mandible to condyloid fossa and from the latter to the maximum height of mandible were 8.5 cm and 2.3 cm, respectively. Finally, the distance from caudal border of mandible to mandibular foramen and from the latter to mandibular angle were 3.5 cm and 4.1 cm, respectively. The craniometrical information provided in this study will be important for clinical maneuvers around the head of the Iranian native donkeys such as regional anesthesia during treating head injury and dental extraction.