Superficial Neck Vasculature of the American Black Bear and its Implications for Intramuscular Tranquilization

Abstract

Many ursid management protocols list the neck region as a target site for intramuscular (IM) delivery of tranquilizer; due to the large muscle mass and relatively thin subcutaneous fat layer. However, the superficial neck vasculature in American black bears has not been well studied. We find that the vasculature resembles that of the giant panda (Davis, 1964). The occurrence of several, potentially tranquilizer dosage related, fatalities in local bears prompted a further exploration of the region. Three bears were dissected with the permission of the New Hampshire Department of Fish and Game: one adult male, one adult female, and one juvenile female. Dissection revealed a large external jugular vein on the anterior surface of the neck, running superficial to the musculature; in the middle of the prescribed tranquilization site. This is contrary to available information of the region, cautioning to avoid only the inferior portion of the neck to avoid the carotid sheath and subclavian vessels. The presence of this vessel creates inherent danger in using this area as a site for the delivery of IM tranquilization, as the dosage would rapidly lower blood pressure and respiratory rate if accidentally delivered intravenously, and should be avoided if possible. This study identified safe boundaries for IM tranquilization to update animal management practices in New England.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.