Background: Animal intubation is necessary in painful surgery procedures in order to maintain general anaesthesia and analgesia. In swine, orotracheal intubation is difficult or impossible; all possible measures to improve it need to be explored. Methods: Two groups of a total of 20 clinically healthy local mixed breed (Sus scrofa domesticus) premedicated swine underwent intubation. The animals were randomly divided into two groups, one using atropine sulphate (A) and one using saline solution (N), prior to endotracheal intubation. Premedication started with intramuscular injection of xylazine, ketamine and fentanyl. Intubation was performed after induction with thiopental sodium administered intravenously with atropine sulphate or saline solution. Larynxes were photographed and filmed and coded images and videos were sent to investigators for evaluation. Result: In this study, a negative effect of atropine sulphate on the laryngeal visibility, opening and accessibility in local mixed breed anesthetized pigs was identified.