Selective treatment of nonsevere clinical mastitis does not adversely affect cure, somatic cell count, milk yield, recurrence, or culling: A systematic review and meta-analysis
de Jong, E. et al. (2022) Selective treatment of nonsevere clinical mastitis does not adversely affect cure, somatic cell count, milk yield, recurrence, or culling: A systematic review and meta-analysis. Journal of Dairy Science. 106 (2), pp. 1267-1286.
The aim of this systematic review and meta-analysis was to examine if selective treatment of clinical mastitis (CM) on dairy farms resulted in similar health outcomes i.e., that would be no worse than blanket treatment of CM. The health outcomes considered were udder health parameters, clinical cure, bacteriological cure, somatic cell count (SCC), milk yield, recurrence, and culling.
A literature search was carried out on four scientific databases to identify published papers since 2010. In addition conference proceedings from the National Mastitis Council and American Dairy Science Association were hand searched. Articles were assessed by two reviewers for inclusion based on the study’s population, intervention, comparison, outcomes and design. Following this process thirteen studies, encompassing 97 dairy herds, remained for data extraction and assessment for risk of bias using the Cochrane Risk-of-Bias tool. Reported outcomes were synthesized with random-effects models and presented as risk ratios or mean differences. GRADE was used to evaluate the certainty of evidence for each outcome measure in the meta-analysis.
Results showed that selective CM treatment was not inferior to blanket treatment for bacteriological cure supported by a high certainty of evidence. The study did not identify any differences between selective and blanket treated CM cases for the outcome measures clinical cure, proportion new IMI, SCC, milk yield, recurrence, and culling, although noninferiority margins could not be determined.
Using traditional analyses, no differences were detected in outcomes between selective and blanket treatment protocols with the exception of clinical cure where the results were confounded by the use of NSAIDs in the selective group only.
Bias could not be ruled out in most studies due to suboptimal randomisation, a finding that would likely only affect subjective outcomes such as clinical cure.
This systematic review and meta-analysis provides evidence that selective treatment of clinical mastitis can be used without adversely affecting outcomes including bacteriological and clinical cure, somatic cell count, milk yield, and incidence of recurrence or culling. This knowledge will help to inform future decision-making and confidence when considering the ‘risk’ of selective treatment of clinical mastitis.
The following may also be of interest:
Swinkels, J.M. et al. (2021) Randomized controlled field trial comparing quarter and cow level selective dry cow treatment using the California Mastitis Test. Journal of Dairy Science, 104 (8), pp. 9063-9081. https://doi.org/10.3168/jds.2020-19258
An inFOCUS summary is available
Schmenger, A. et al. (2020) Implementation of a targeted mastitis therapy concept using an on-farm rapid test: antimicrobial consumption, cure rates and compliance. Veterinary Record 187 (10) p. 401. https://dx.doi.org/10.1136/vr.105674
An inFOCUS summary is available
Responsible use of antibiotics in veterinary practice [inFOCUS][online]. Available from: https://infocus.rcvsknowledge.org/amr_responsible-use-of-antibiotics-in-veterinary-practice/ [Accessed 20 February 2023]
Farm Vet Champions. [RCVS Knowledge][online]. Available from: https://learn.rcvsknowledge.org/course/index.php?categoryid=6 [Accessed 20 February 2023]
Claiming CPD for reading inFOCUS articles
Reading and reflecting on articles can count towards your CPD, and we have a template to help you with the process.
Image copyright attribute: pressmaster