Suprascapular nerve decompression for treatment of neuropathy in a bucking bull.

CASE DESCRIPTION: A 3-year-old 639-kg (1,406-lb) American bucking bull was examined because of a 4-day history of right forelimb lameness that began after the bull sustained an injury to the right shoulder region while exiting the chute during a rodeo. CLINICAL FINDINGS: A 10 × 10-cm soft tissue swelling was present over the right shoulder region. Ultrasonographically, the contour of the scapular spine, bicipital bursa, bicipital tendon, and greater tubercle of the humerus appeared unremarkable; the swelling appeared to be a hematoma overlying the distal aspect of the scapula. No external wounds, palpable joint effusion, or swellings were noted on examination of the distal portions of the limbs. The bull developed atrophy of the supraspinatus and infraspinatus muscles with lateral abduction of the shoulder joint when walking. Electromyography revealed decreased innervation to the supraspinatus and infraspinatus muscles consistent with suprascapular neuropathy. TREATMENT AND OUTCOME: The suprascapular nerve was surgically decompressed by removing the entrapping hematoma and periosteum and performing a notch resection of the scapula; dexamethasone (40 mg) was administered prior to closure. The bull was discharged 5 days after surgery; no lameness was evident at the time of discharge. The owner was instructed to restrict the bull to a stall or small pen for 6 weeks. Four months after surgery, the muscle atrophy had substantially improved, and the bull returned to bucking. CLINICAL RELEVANCE: Findings suggested that suprascapular neuropathy can develop in bulls secondary to injury and that suprascapular nerve decompression may improve nerve function, muscle atrophy, and gait.

Structured literature review of responses of cattle to viral and bacterial pathogens causing bovine respiratory disease complex.

Bovine respiratory disease (BRD) is an economically important disease of cattle and continues to be an intensely studied topic. However, literature summarizing the time between pathogen exposure and clinical signs, shedding, and seroconversion is minimal. A structured literature review of the published literature was performed to determine cattle responses (time from pathogen exposure to clinical signs, shedding, and seroconversion) in challenge models using common BRD viral and bacterial pathogens. After review a descriptive analysis of published studies using common BRD pathogen challenge studies was performed. Inclusion criteria were single pathogen challenge studies with no treatment or vaccination evaluating outcomes of interest: clinical signs, shedding, and seroconversion. Pathogens of interest included: bovine viral diarrhea virus (BVDV), bovine herpesvirus type 1 (BHV-1), parainfluenza-3 virus, bovine respiratory syncytial virus, Mannheimia haemolytica, Mycoplasma bovis, Pastuerella multocida, and Histophilus somni. Thirty-five studies and 64 trials were included for analysis. The median days to the resolution of clinical signs after BVDV challenge was 15 and shedding was not detected on day 12 postchallenge. Resolution of BHV-1 shedding resolved on day 12 and clinical signs on day 12 postchallenge. Bovine respiratory syncytial virus ceased shedding on day 9 and median time to resolution of clinical signs was on day 12 postchallenge. M. haemolytica resolved clinical signs 8 days postchallenge. This literature review and descriptive analysis can serve as a resource to assist in designing challenge model studies and potentially aid in estimation of duration of clinical disease and shedding after natural pathogen exposure.