Estimations of Milk and Meat Withdrawal Times of Ketamine and Lidocaine in Adult Holstein Cows

Abstract

Ketamine is a dissociative anesthetic commonly used for short-term and induction of anesthesia in bovine species. Ketamine has recently become popular for use as a constant-rate infusion for continuous pain relief. Lidocaine, a local anesthetic, is frequently used for local infiltration and epidural nerve blocks. Two of the most common local blocks in adult cattle are the inverted-L local infiltration and caudal epidural nerve blocks. These blocks are utilized for numerous standing surgical procedures such as cesarean sections, obstetric manipulations, correction of a displaced abomasum and perineal surgery. These animals may occasionally be sent for slaughter following a surgical procedure, and the Food and Drug Administration (FDA) has a zero-tolerance policy for drug residues in meat and milk. There is limited information and no published data on meat and milk withdrawal times for ketamine anesthesia or lidocaine administration via these two different techniques. The objectives of this study were to investigate the pharmacokinetics of ketamine following administration of a single intravenous dose and lidocaine administered via inverted-Land caudal epidural nerve blocks, and to establish the withdrawal times for meat and milk of these two anesthetics in mature Holstein cows.