It is estimated 45% of calves in the UK have pneumonia before weaning with most cases being seen in calves at 5 weeks old.
Detection and Diagnosis
Accurate detection of pneumonia is difficult, and cases are often missed. Thoracic ultrasound screening of calves at 3-6 weeks old can assist in determining the level of pneumonia in your young stock.
Healthy lung image from thoracic ultrasound.
Thoracic ultrasound is a quick and easy process and is much more sensitive at detecting pneumonia than calf scoring or auscultation. Unfortunately ultrasound detects lesions rather than active infections, so is used more as a tool of assisting calf rearers in becoming more accurate at detecting lung infections rather than a diagnostic tool for treatment.
Diagnosing the responsible agent for pneumonia in your calves can be beneficial if deciding to use vaccines to help reduce clinical cases. Diagnostic tests include nasopharyngeal swabs, bronchioalveolar lavage and serological tests.
Commonly used vaccines in the UK
Pathogen | Nasym | Bovalto respi 3 | Bovalto IN | Bovilis bovipast | Bovilis IN | Rispoval 2, 3, 4 | Hiprabovis somni/lkt |
RSV | | | | | | 2,3,4 | |
PI3 | | | | | | 2,3,4 | |
IBR | | | | | | 4 | |
M. haemolytica | | | | | | | |
P. multocida | | | | | | | |
H. somni | | | | | | | |
Control
Preventing pneumonia cases relies on limiting spread of disease from older stock to younger stock and optimising the housing environment.
Keeping calf groups small (6-8) and delaying mixing until 12 days old help to reduce the number of pneumonia cases.
Windspeed, temperature and relative humidity meter.
Calf housing environment should have windspeed 0.2-0.5m/s, encouraging ventilation of 4 air changes per hour without creating draughts. Enclosed calf sheds will need to rely on positive pressure ventilation to achieve this.
Calf accommodation should have a relative humidity of <75%, this is achieved with adequate bedding levels to keep beds dry, and ideally a 2% slope to allow drainage.
Treatment
A 2013 and 2016 (revised) study looked at antibiotic treatment options for bovine respiratory disease in calves and ranked antibiotic treatments by efficacy and likelihood of re-treatment. The study placed the following antibiotics in order
Tulathromycin < Florfenicol < TMPS < Oxytetracycline
Several studies have found benefits of treating calves with BRD with NSAIDs and so all cases should receive NSAID treatment.
Mahendran, S. A. (2020). Use of fever detection in combination with thoracic ultrasonography to identify respiratory disease, and compare treatments of antimicrobials and NSAID: a randomised study in dairy calves. Veterinary record open, 7(1), e000415.
Johnson KF, Chancellor N, Burn CC, Wathes DC. Prospective cohort study to assess rates of contagious disease in pre-weaned UK dairy heifers: management practices, passive transfer of immunity and associated calf health. Vet Rec Open. 2017;4(1):e000226. Published 2017 Nov 28. doi:10.1136/vetreco-2017-000226
Buczinski, S., Forté, G., Francoz, D., & Bélanger, A. M. (2014). Comparison of thoracic auscultation, clinical score, and ultrasonography as indicators of bovine respiratory disease in preweaned dairy calves. Journal of veterinary internal medicine, 28(1), 234-242.
Curtis GC, Argo CM, Jones D, Grove-White DH. Impact of feeding and housing systems on disease incidence in dairy calves. Vet Rec. 2016;179(20):512
A. O’Connor et al.A mixed treatment comparison meta-analysis of antibiotic treatments for bovine respiratory disease Prev. Vet. Med. (2013)
Mahendran, S. A., Booth, R., Burge, M., & Bell, N. J. (2017). Randomised positive control trial of NSAID and antimicrobial treatment for calf fever caused by pneumonia. Veterinary Record, 181(2), 45-45.
Lockwood, P. W., Johnson, J. C., & Katz, T. L. (2003). Clinical efficacy of flunixin, carprofen and ketoprofen as adjuncts to the antibacterial treatment of bovine respiratory disease. Veterinary record, 152(13), 392-394.