Factors influencing dairy farmers' antibiotic use: An application of the COM-B model

In dairy farming, mastitis treatment is the most common reason for antimicrobial use. The overuse or misuse of antibiotics in agriculture has been associated with the development and spread of antimicrobial resistance (AMR). Traditionally, blanket dry cow therapy (BDCT), in which all cows receive antibiotic treatment, was used prophylactically to prevent and manage disease spread. In recent years, there has been a move toward selective dry cow therapy (SDCT), in which only clinically infected cows are treated with antibiotics. This study aimed to explore farmer attitudes toward antibiotic use (ABU), using the COM-B (Capability-Opportunity-Motivation-Behavior) model as a framework, to identify predictors of changing behavior toward SDCT and suggest interventions to encourage its uptake. Participant farmers (n = 240) were surveyed online between March and July 2021. Five items were found to be significant predictors of farmers having stopped BDCT: (1) having lower knowledge of AMR, (2) greater awareness of AMR and ABU (Capability), (3) feeling social pressure to reduce ABU (Opportunity), and (4) having greater professional identity, and (5) having positive emotions associated with stopping BDCT (Motivation). Direct logistic regression found that these 5 factors explained between 22 and 34.1% of the variance in making changes to BDCT practices. Additionally, objective knowledge was not correlated with current positive antibiotic practices, and farmers often perceived their antibiotic practices as more responsible than they actually were. A multifaceted approach, encompassing each of the predictors highlighted, should be taken to encourage farmer behavior change in relation to stopping BDCT. Additionally, as farmers' perceptions of their own behaviors may not align with their actual practices, awareness raising of what constitutes "responsible" behavior should be targeted at dairy farmers to motivate them to take action and adopt more responsible antibiotic practices.