Assessing experimental visceral pain in dairy cattle: A pilot, prospective, blinded, randomized, and controlled study focusing on spinal pain proteomics.

Few studies have verified the validity of behavioral and physiological methods of pain assessment in cattle. This prospective, blinded, randomized controlled experimental study aimed to validate different methods of pain assessment during acute and chronic (up to 21 d postintervention) conditions in dairy cattle, in response to 3 analgesic treatments for traumatic reticuloperitonitis. Cerebrospinal fluid (CSF) biomarkers and mechanical sensitization were measured as indicators of centralized pain. Proteomics in the CSF were examined to detect specific (to pain intensity) and sensitive (responsive to analgesia) markers. Recordings of spontaneous behavior with video analysis, telemetered motor activity, pain scales, electrodermal activity, and plasma cortisol concentration were quantified at regular intervals. Cows were assigned to group 1 (n=4, standard control receiving aspirin), group 2 (n=5, test group receiving preemptive tolfenamic acid), or group 3 (n=3, positive control receiving preemptive multimodal analgesia composed of epidural morphine, plus tolfenamic acid and butorphanol). Rescue analgesia was administered as needed. Generalized estimating equations tested group differences and the influence of rescue analgesia on the measurements. All 3 groups demonstrated a long-term decrease in a CSF protein identified as transthyretin. The decrease in transthyretin expression inversely correlated with the expected level of analgesia (group 1<2<3). Moreover, in group 1, CSF noradrenaline decreased long term, cows were hypersensitive to mechanical stimulation, and they demonstrated signs of discomfort with higher motor activity and "agitation while lying" recorded from video analysis. Decreased "feeding behavior," observer-reported pain scales, electrodermal activity, and plasma cortisol concentration were inconsistent to differentiate pain intensity between groups. In summary, changes in CSF biomarkers and mechanical sensitization reflected modulation of central pain in dairy cows. The spontaneous behavior "agitation while lying" was the only behavioral outcome validated for assessing acute and chronic pain in this visceral pain model.

Correction of a severe torsional malunion of the metacarpus in a calf by transverse osteotomy, transfixation pinning and casting.

A four-month-old Holstein heifer was presented for evaluation of an angular limb deviation. Upon initial presentation, the heifer was not clinically lame. An external rotation of 90 degrees of the fetlock was observed in the left forelimb. Radiographs identified a healing closed spiral fracture of the third and fourth metacarpal bones, with a 90 degrees external torsion. A mid-metacarpal bone transverse osteotomy was performed after insertion of transcortical pins in the distal and proximal part of the third and fourth metacarpal bones and in the distal radius. The reduction was performed in order to align both fetlock and carpal joints and a fiberglass cast was applied to complete the external fixation. A satisfactory outcome was associated with the treatment.