PSX-29 - LidoBandsTM for use in lambs

Abstract: Abstract: The purpose of this study was to evaluate in vivo release levels of lidocaine into scrotal neck tissues and tail tissues following the application of lidocaine-loaded elastrator bands (LLBs) at acute time points (0.5, 1, 2, 24, and 72 hours) and chronic time points (14, 21, 28, and 35 days). To correlate an animal’s reaction to peripheral variable nerve stimulation with scrotal tissue lidocaine concentration. To correlate cortisol and substance p levels in treated animals at baseline (time 0) and 24, 72, 14, 21, 28, and 35 days to a control group. Fifty lambs were divided into ten groups consisting of Acute Pain Groups: Group A: 5 intact males. After baseline body weights, blood samples, and electro-cutaneous responses were collected, animals were band-castrated and tail-docked via LLB’s on Day 0, T=0. At T=0.5 hrs., the band was removed, and an electro-cutaneous response was measured at the tissue at the band sites. Punch tissue biopsies (including skin and subcutaneous tissue) were collected from the areas in direct contact with the band at each site for a total of 4 biopsies per animal. Group B: repeat of group A with the band removed and animal tested at T=1 hr. Group C: T=2 hrs. Group D: T=24 hrs. Group E: T=72 hrs. Chronic Pain Groups: Group F: T=14 days. Group G: T=21 days. Group H: T=28 days. Group I: T=35 days. Control Group: Group J: repeat of group A except animals were band castrated and tail-docking with control bands (i.e., no lidocaine) on Day 0. Body weight was recorded at T=0 and 14, 21, and 28 days. A blood sample was collected at T=0, 24, 72 hrs, then T= 8, 21, 28, and 35 days. LLBs yielded significantly lower stimulation scores by 1 hour (60 mins) post-banding with the tails and by 2 hours (120 mins) for the scrotums. There were no adverse events or device failures (i.e., band breakage or failure to castrate/ tail-dock) observed during this study. Lidocaine-infused bands hold promise for reducing pain associated with castration and tail docking in lambs.