Abstract
Teat sealants (TSs) consist of sterile formulations with no antibacterial activity. Alone or in combination with antimicrobial (AM) or non-AM treatments, TSs have been commonly used in dairy cows at dry-off to prevent intra-mammary infections (IMIs) during the dry period. This study aimed to identify and synthesise the available evidence on the efficacy of combining TSs with AM treatments on the incidence and prevalence of IMIs. A comprehensive search of three electronic databases, two relevant conference proceedings, and reference lists of reviews and eligible articles was conducted to retrieve and identify studies that could answer the following question: in dairy cows, how does the efficacy of an AM–TS combination administered at dry-off compare with an AM alone for preventing new IMI? In addition to the general IMIs, bacterial species-specific data were extracted and combined into nine distinct pathogen groups: coagulase-positive and negative staphylococci; S. dysgalactiae; non-dysgalactiae Streptococci; E. coli; non-E. coli Enterobacteriaceae; Corynebacterium spp.; yeast and other frequent mastitis pathogens. The structural relationship between each study's prevalence and incidence, as the new (incidence) and persistent (uncured) infections make up the prevalence, was utilised to approximate a variance-covariance matrix for the within-study correlation between their study-specific log odds ratios (ORs). A bivariate random-effects meta-analysis was employed, utilising the within- and between-study correlations to synthesise both outcomes simultaneously. The risk of bias was assessed using the Cochrane ROBINS-I tool, and the quality of the body of evidence was rated using the GRADE approach. A total of 17 trials (16 studies), providing either IMIs incidence (n = 4), prevalence (n = 3) or both (n = 10), were identified. Overall, quarters infused with AM-TS combinations showed lower odds of new IMIs post-calving (OR=0.70; 95% CI=0.57–0.86; Wald test P < 0.001) than those which received only AMs. Across the pathogen groups, varying levels of reduction of new IMIs were found, where administration of TSs was most effective against S. dysgalactiae (OR=0.47; 95% CI=0.23–0.98), non-dysgalactiae streptococci (OR=0.60; 95% CI=0.49–0.74), E. coli (OR=0.62; 95% CI=0.50–0.77), Corynebacterium spp. (OR=0.68; 95% CI=0.52–0.90) and coagulase-negative staphylococci (OR=0.85; 95% CI=0.76–0.94). However, additional TS infusion did not significantly reduce new IMIs in the remaining pathogen groups. The current meta-analytic evidence supports the efficacy of using TS add-on infusions in dairy cows at dry-off for reducing the incidence and prevalence of IMIs post-calving; however, pathogen group differences should be considered.
| Original language | English (US) |
|---|---|
| Article number | 105864 |
| Journal | Preventive Veterinary Medicine |
| Volume | 213 |
| DOIs | |
| State | Published - Apr 2023 |
Bibliographical note
Funding Information:MA and FK were supported by the NSERC-CREATE in Milk Quality program.The authors would like to thank Dr. William Montelpare, Department of Applied Human Sciences, Faculty of Science, University of Prince Edward Island, for his participation in the initial steps of the selection of studies. Also, we are thankful to the staff of the Robertson Library, University of Prince Edward Island, for assistance in obtaining the full text of manuscripts not otherwise accessible. We also thank Raphaël Braga, librarian, Faculté de médecine vétérinaire, Université de Montréal, Canada, for his help in developing, elaborating, and validating the search keywords and syntax.
Funding Information:
MA and FK were supported by the NSERC-CREATE in Milk Quality program.
Publisher Copyright:
© 2023 Elsevier B.V.
Keywords
- Bivariate meta-analysis
- Borrowing of strength
- Dry cow therapy
- Teat sealant