Clinical and Behavioral Changes Associated with using Xylazine only or Xylazine-epinephrine Combination for Caudal Epidural Analgesia in Cattle

Abstract

In recent years, various anaesthetic agents and mixtures had been evaluated for caudal epidural analgesia in cattle with a variety of results. Caudal epidural analgesia is a routine and established technique for a variety of surgical and obstetrical procedures in cattle and might depend on the volume of local analgesic. The objective of the present work to compare between the analgesic efficacy of xylazine alone and that of Xylazine-epinephrine combination in caudal epidural analgesia through studying the clinical and behavioral changes as well as estimating degrees of ataxia, sedation and analgesia in cows throughout monitoring their efficacies pre-epidural (Minute 0) injection or post-epidural injection (Minutes 10, 30, 60, 90, 120, 150 and 180). The study was conducted on clinically healthy non-pregnant cross cows (n=20). They were classified into two equal groups. The first one received epidural injection of 0.05 mg/kg xylazine and thus was referred as Xyla^gr. The second group was epidurally treated through injection of combination of 0.05 mg/kg xylazine and Epinephrine and thus was referred as Xyla-Epin^gr. All animals were subjected for through clinical examination as well as monitoring of different degrees of ataxia, sedation and analgesia parameters. There was no statistically significant difference in the onset of analgesia between xylazine epidural injection (11.85±1.25 minutes) and xylazine with epinephrine (12.01±1.05 minutes). Epidural administration of xylazine with epinephrine produced a significantly longer duration of analgesia (161±7.62 minutes) than that produced by epidural injection xylazine alone (136.20±7.13 minutes). Administration of xylazine alone resulted in mild to moderate sedation with mild ataxia, as well as cutaneous analgesia for the perineal region while xylazine with epinephrine produced mild sedation without ataxia, as well as cutaneous analgesia for the perineal region. The study concluded the higher efficacy of xylazine-epinephrine combinations as a caudal epidural analgesic drug compared with that of xylazine alone. Xylazine-epinephrine combination has more rapid onset of recovery from signs of ataxia and sedation than xylazine alone, which make it more suitable than xylazine in cattle as an intraoperative and postoperative analgesia.