Randomized control trial assessing the efficacy of pain control strategies for caustic paste disbudding in dairy calves younger than 9 days of age

摘要

Disbudding is a common procedure practiced in thedairy industry and is known to cause pain when performedwithout pain control. Dairy producers who disbudcalves with caustic paste are less likely to providepain control than those using cautery. Little researchhas been conducted on pain control for caustic pastedisbudding and no studies have specifically examinedcalves under 9 d of age. The objective of this study wasto evaluate the efficacy of local anesthesia and nonsteroidalanti-inflammatory drug analgesia on indicatorsof pain and inflammation in dairy calves disbuddedusing caustic paste. One hundred forty Holstein heifercalves 1 to 9 d of age were enrolled in 28 blocks andrandomly allocated to 1 of 5 treatments: sham control(SH); positive control (POS); lidocaine cornual nerveblock (LC); meloxicam (MEL); and lidocaine cornualnerve block plus meloxicam (LCM). We measured outcomesincluding serum cortisol and haptoglobin, pressuresensitivity, and lying behavior. Data were analyzedusing mixed linear regression models with treatmentas a fixed effect, baseline values as a covariate, andtrial block as a random effect. Compared with the POSgroup, the LCM group had reduced serum cortisol at15, 30, 45, and 60 min post-disbudding; cortisol valueswere not different between LC, LCM, and SH calves atthese time points. At 60, 90, 120, and 180 min postdisbudding,LCM calves had reduced cortisol comparedwith LC calves, whereas, values did not differ betweenLCM and SH calves at these time points. At 3 to 4d post-disbudding, the LCM group tended to havereduced haptoglobin, but no differences were foundbetween groups at 180 min and 7 d post-disbudding.At 60, 90, and 120 min post-disbudding, LC and LCMtreated calves had decreased pressure sensitivity comparedwith other groups. No differences were seen inpressure sensitivity between groups at 180 min, 3 to 4or 7 d post-disbudding. No differences in lying behaviorwere found between treatment groups on any of the 7 dfollowing disbudding. These findings demonstrate thatthe combination of a local anesthetic with a nonsteroidalanti-inflammatory drug is beneficial for reducingindicators of pain and inflammation in young calvesdisbudded with caustic paste.