Non-Steroidal Anti-Inflammatory Drugs: Pharmacokinetics and Mitigation of Procedural-Pain in Cattle

SIMPLE SUMMARY: Castration and disbudding, common husbandry procedures used in cattle livestock production industries, are recognized as being painful. In the United States (U.S.), these procedures are frequently performed without pain relief. Although non-steroidal anti-inflammatory drugs (NSAIDs) are used in food-animal production systems, no such pain relief drugs are federally approved in the U.S. for controlling procedural pain in cattle to date. Recent increases in consumer, retailer and producer commitment to improving the welfare of food-animals necessitate a closer look into pain control efforts for livestock. Therefore, this review comprehensively evaluated existing literature to summarize three NSAIDs (meloxicam, flunixin and aspirin) (1) pharmacokinetics and (2) administration outcome in regard to pain control during castration and disbudding procedures, in cattle. The sample size contained notable variability and a general deficiency of validated and replicated methodologies for assessing pain in cattle represent on-going challenges. Future research should prioritize replication of pain assessment techniques across different experimental conditions to close knowledge gaps identified by the present study and facilitate examination of the effectiveness of pain relief drugs. ABSTRACT: Common routine management practices in cattle, such as castration and disbudding, are recognized as being painful. In the United States (U.S.), these procedures are frequently performed without pain mitigation and there are currently no drugs federally approved for such use. Non-steroidal anti-inflammatory drugs, such as meloxicam, flunixin meglumine and aspirin, are the most commonly used analgesics in U.S. food-animal production systems. However, the body of research investigating the effectiveness of these pharmaceuticals to control pain in cattle at castration and disbudding has not been comprehensively evaluated. Therefore, this review examined existing literature to summarize meloxicam, flunixin and aspirin (1) pharmacokinetics (PK) and (2) administration outcome in regard to pain control during castration and disbudding procedures, in cattle. Following systematic searches and screening, 47 PK and 44 publications were extracted for data and are presented. The sample size contained notable variability and a general deficiency of validated and replicated methodologies for assessing pain in cattle remain substantial challenges within this research area. Future research should prioritize replication of pain assessment methodologies across different experimental conditions to close knowledge gaps identified by the present study and facilitate examination of analgesic efficacy.