Comparative efficacy of blanket versus selective dry-cow therapy: a systematic review and pairwise meta-analysis

Winder, C. B. and Sargeant, J. M. and Kelton, D. F. and Leblanc, S. J. and Duffield, T. F. and Glanville, J. and Wood, H. and Churchill, K. J. and Dunn, J. and Bergevin, M. D. and Dawkins, K. and Meadows, S. and O’Connor, A. M.

Anim Health Res Rev (2019) 20: 217–228

DOI: 10.1017/s1466252319000306

Abstract

A systematic review and meta-analysis were conducted to determine the efficacy of selective dry-cow antimicrobial therapy compared to blanket therapy (all quarters/all cows). Controlled trials were eligible if any of the following were assessed: incidence of clinical mastitis during the first 30 DIM, frequency of intramammary infection (IMI) at calving, or frequency of IMI during the first 30 DIM. From 3480 identified records, nine trials were data extracted for IMI at calving. There was an insufficient number of trials to conduct meta-analysis for the other outcomes. Risk of IMI at calving in selectively treated cows was higher than blanket therapy (RR = 1.34, 95% CI = 1.13, 1.16), but substantial heterogeneity was present (I2 = 58%). Subgroup analysis showed that, for trials using internal teat sealants, there was no difference in IMI risk at calving between groups, and no heterogeneity was present. For trials not using internal teat sealants, there was an increased risk in cows assigned to a selective dry-cow therapy protocol, compared to blanket treatment, with substantial heterogeneity in this subgroup. However, the small number of trials and heterogeneity in the subgroup without internal teat sealants suggests that the relative risk between treatments may differ from the determined point estimates based on other unmeasured factors.

Citation

Winder, C. B., Sargeant, J. M., Kelton, D. F., Leblanc, S. J., Duffield, T. F., Glanville, J., Wood, H., Churchill, K. J., Dunn, J., Bergevin, M. D., Dawkins, K., Meadows, S., & O’Connor, A. M. (2019). Comparative efficacy of blanket versus selective dry-cow therapy: a systematic review and pairwise meta-analysis. Anim Health Res Rev, 20(2), 217–228. https://doi.org/10.1017/s1466252319000306 Animals, Female, Cattle, Anti-Bacterial Agents/*therapeutic use, *Lactation, Mammary Glands, Animal, *dairy cattle, *dry-off, Mastitis, Bovine/*prevention & control, *amu, *antibiotic, *mastitis

Keywords

• Animals
• Female
• Cattle
• Anti-Bacterial Agents/*therapeutic use
• *Lactation
• Mammary Glands
• Animal
• *dairy cattle
• *dry-off
• Mastitis
• Bovine/*prevention & control
• *amu
• *antibiotic
• *mastitis