Development and Field Validation of Lidocaine-Loaded Castration Bands for Bovine Pain Mitigation

Abstract

Castration is among the most common management procedures performed in the dairy and beef cattle industries and is mainly performed by surgery or elastic banding. Despite the various benefits of castration, all methods produce pain and distress. Castration by banding is simple, inexpensive, produces fewer complications, and can be performed in a high-throughput manner. Because lidocaine, a local anesthetic, can be delivered to trauma sites topically, we have formulated lidocaine-loaded castration bands (LLBs) to deliver local pain relief to calves during banded castration. The initial lidocaine content of three band types developed was between 80 and 200 mg per band. The transfer kinetics of lidocaine into tissue was determined in vitro, indicating a rapid release for the first 30 min, followed by a slow release lasting at least 48 h. Furthermore, the lidocaine delivery and pain mitigation effects of these LLBs were compared to standard lidocaine injections in vivo. Field studies indicated that LLBs performed at least as well as lidocaine injections for short-term lidocaine delivery into tissues and pain mitigation. Moreover, LLBs significantly outperformed lidocaine injections for long-term delivery and pain mitigation. The concentrations of lidocaine in the LLB-treated tissue samples were generally in the range of 0.5–3.5 mg of lidocaine per gram of tissue and were overall highest after 6 h. Lidocaine-loaded elastration bands deliver therapeutic quantities of lidocaine into scrotal tissues over a period of at least seven days in cattle. This approach would provide long-term pain mitigation to the animals and, by avoiding surgery or the administration of injections, would also decrease the time and handling costs for the producer.

Drug-Eluting Rubber Bands for Tissue Ligation

“…Dimenhydrinate and tavaborole displayed a very strong initial burst release over 1 day (Figure S7F,G), while salicylic acid displayed first order release kinetics closer to those of lidocaine (Figure S7H). ,, We investigated the function of the SIS bands and released drug via cell culture studies. At first, the effect of salicylic acid released was measured from the SIS bands on cell viability.…”

“…Of note, drugs that exhibited good loading and release behaviors in this work were soluble in chloroform and at least slightly soluble in water. 14,34,35 We showed that the bands released functional drugs to affect both cell and animal models. Finally, we found that SIS bands can be used for binding of enteric tissue, as in hemorrhoid ligation, and that drugs could be released into the local tissue at therapeutic concentrations.…”

“…Commercially available rubber bands for ligation treatment are commonly manufactured either from natural rubber latex, where the primary elastic component is polyisoprene, or from nonlatex elastic materials, such as synthetic polyisoprene, polyurethane, or silicone. These alternatives display different mechanical properties and are less sturdy than latex bands but are indispensable due to the fact that many patients are sensitive to constituent allergens present in latex which is derived from Hevea brasiliensis , commonly known as “the rubber tree”. , Previous works have shown drug and protein release from natural rubber latex membranes for wound dressings and livestock castration. − In non-latex elastomers, silicone based intravaginal rings for controlled release have been commercially available since 1992 and first patented in 1970 …”

Pain Management in Farm Animals: Focus on Cattle, Sheep and Pigs

“…All methods of castration at any age in any species are painful [ 86 , 87 , 88 ]. There is minimal evidence of analgesia efficacy for surgical castration in pigs with any of the currently approved NSAIDs or local anesthetics, such as lidocaine [ 52 , 89 , 90 , 91 ], and some evidence of partial efficacy for analgesia following castration by band or surgical means in beef cattle [ 92 , 93 ]. In general, there is a lack of information about analgesia efficacy for surgical castration of sheep and few licensed analgesic drugs available for use [ 94 ] in this species.…”

“…In one study, an analgesic benefit was observed after the administration of morphine and flunixin meglumine [ 45 ]. One promising analgesia technique that has been recently described is the use of lidocaine-loaded castration bands in 3–4-week-old beef calves [ 92 ]. This method provides sustained transcutaneous release of local anesthetic within the scrotal tissues while the band is in place.…”