Author: Gregori Skatchkoff

Dry cow antibiotic therapy (DCT) is the administration of long acting intramammary antibiotics at the time of dry-off. This practice gained widespread implementation in the 1960s as part of the ‘five point plan’ in the UK and numerous clinical trials have demonstrated its efficacy in promoting udder health through the control of intramammary infections (IMI) during the dry period (Halasa et al., 2009a; Halasa et al., 2009b). In many countries, DCT is mostly used in a ‘blanket’ fashion (blanket dry cow therapy; BDCT), which involves treatment of all quarters at dry-off. However, the large majority of quarters in modern well managed dairy herds are not infected at dry-off (Rowe et al., 2019; McDougall et al., 2022), and therefore, unlikely to benefit from DCT. Furthermore, BDCT significantly increases total antibiotic usage (de Campos et al., 2021), which farmers are increasingly expected to use sparingly.