Understanding how dairy farmers use antibiotics, whether they are aware and concerned about the emerging issue of AMR and whether they are willing to change their practices is a crucial step in developing strategies to appropriate antibiotic use.
This study indicated that participants’ knowledge about antibiotics and AMR was moderate. Similar to the UK general population [15], approximately one-third of the farmers believed that antibiotics could be used to treat virus infections, and nearly half thought antibiotics have an anti-inflammatory and/or antipyretic activity. The understanding of AMR was accurate for only 34%, a smaller proportion than that reported in a similar survey in England (55%) [12]. The difference may be due to a stricter interpretation in our study, as only the definition of AMR as “bacteria developing resistance to antibiotics” was considered correct. These findings suggest that the main purpose of AMU and the significance of AMR might still be unknown for some dairy producers. Providing farmer education focused on antimicrobials and AMR could promote more responsible antimicrobial usage.
Our survey found that reported awareness of RUMA guidelines was higher than previously described by Jones et al in English and Welsh producers, published in 2015 [11]. A potential explanation may be a trend for farmers to be more exposed to AMU restrictions and regulations in recent years, although this may not translate into knowledge. Farm owners' familiarity with the guidelines was greater than dairy managers. Farm employees are often the main ones responsible for administering antibiotics, particularly in large-size herds. Our results suggest that in addition to the need for campaigns regarding responsible AMU in the Scottish dairy sector, knowledge and awareness should be disseminated consistently among all stockholders handling antibiotics.
Farmers’ implementation of advice depends on several factors, such as the person delivering the recommendation [16]. Similar to previous studies [11, 13, 17–19], this survey reveals that herd veterinarians are regarded as the most reliable source of information and the most influencing social referent. Moreover, more frequent contact and discussion with the veterinarian about AMR were associated with positive outcomes, such as the likelihood of implementing medicine protocols on the farm. Since vet recommendations have the most decisive influence on farmers’ behaviour, practitioners must be aware of their role in tackling antimicrobial resistance.
As previously described in another UK farmers survey [19], we found that discussion about AMR with the veterinarian was sporadic for most of the respondents. AMR discussion happened mostly once a year, likely at the time of the AMU review required by the Red Tractor Assurance [20]. The lack of communication around AMR may be due to the rare contact, as in this and other studies, veterinarians are not often consulted before administering antibiotics [11, 21]; or it could be linked to veterinarians’ perceptions that dairy producers are reluctant to change their practices [13, 22], or to veterinarians’ time limitations [23]. According to research conducted in the UK, despite antimicrobial stewardship principles being included in most undergraduate veterinary schools, there is still room for improvement in students’ education in this area [24].
Farmers’ decision-making around AMU is influenced by several factors, with animal welfare and profitability being the most reported [11, 13, 18, 21, 25]. Contrary to other authors [17, 25, 26], we found that economic constraint was not an important reason for not seeking veterinarian advice. Rather, farmers tend to rely on personal skills and experience to treat sick animals, and veterinary consultations are often considered unnecessary. This may be partially explained by the widespread implementation of written treatment protocols which are more popular than in other countries [25–27]. Similarly, we found that cost was the least important factor for antibiotic decision-making, whereas previous usage experience was ranked as the most important. In previous studies, farmers reported relying much on pre-existing experiences and some more than on veterinarians’ advice [28, 29]. Repeated positive outcomes of specific antibiotics may lead farmers to have preferred treatments that they consider more effective. Ritualising drug choice is likely to act as a barrier to farmers’ responsible AMU and behavioural interventions are more difficult when there is an over-reliance on previous experiences [30]. Since farmers are reluctant to implement new recommendations if they do not believe they are practical and feasible [31], it is essential to educate and promote the effectiveness of alternative and responsible practices to change deeply embedded behaviours. Strategies, such as showing results in other contexts, may help to change farmers’ perceptions [16].
Previous research on dairy farmers’ AMU behaviour highlighted the importance of external approval and social norms conformity [11, 21, 32, 33]. Unlike other surveys [18, 21], farmers in our study did not express the need to be considered a “good farmer” by other producers and did not feel pressured by peers’ opinions (e.g., colleagues, family, and other farmers). Gerber and colleagues reported similar results [34], with most participants not motivated by other farmers to reduce their antimicrobial usage. On the other hand, we found that farmers valued the opinion of some social referents in the dairy industry (e.g., milk buyers and consumers), and minimising residues and meeting milk buyer standards were the main drivers for lower antimicrobial usage. Although some farmers may feel constrained by public demand for antibiotic-free products and the negative perception of the industry [18, 21], our results suggest a positive impact of consumer pressure in shaping and improving AMU in livestock. Since consistent findings were reported in other UK studies [11, 13], farmers’ attitudes towards consumers likely depend on the agricultural framework of the country.
Farmers indicated mastitis as the main reason for AMU and penicillin as the most used antibiotic, as reported by previous studies in the UK and Scotland [12, 35]. However, in the scenarios section, we found similar results to Jones and co-workers: antibiotics were most frequently chosen as a treatment option in calf pneumonia, followed by clinical mastitis [11]. None of the respondents would have treated the calf diarrhoea with antibiotics, suggesting a much lower AMU for this condition than in UK beef calves [19]. The different findings may be due to more extensive production in the beef sector, with less veterinarian contact and treatment protocols.
This survey revealed that most farmers had already taken steps to reduce AMU: around 90% had practices implemented on farms, with SDCT being the most cited. The presence of treatment protocols was widespread among participants, and generally, these were more popular than in other studies [25, 27]. This may be explained by the larger size of the Scottish herds compared to other EU countries and by the compulsory requirement set by some UK milk buyers [14]. The culture and sensitivity of samples were reported to be used only occasionally and to a lesser extent than in other countries [25]. Interestingly, lab costs were a limiting factor for only a few farmers, whereas the main reason for not using this practice was the delay in the results. The clinical disease scenarios suggested that producers were more likely to collect a sample for culture in case of a disease outbreak (e.g., calf diarrhoea) rather than for diagnostic testing in an individual animal infection (e.g., cow mastitis). Clinical mastitis is often treated symptomatically without knowing the aetiology, so many antimicrobial administrations are unnecessary [36]. Farmers need to be trained to identify more precisely which animals need therapy and to ensure evidence-based antimicrobial treatments. Newer point-of-care diagnostics may overcome some of the limitations of classic laboratory tests and offer more rapid results [37].
It was also found that some irresponsible practices are still widespread in Scotland. For instance, in two of the clinical disease scenarios, 25 and 30% of the farmers would feed antibiotic waste milk to calves. This practice seems to be reduced compared to past years in the UK [12, 38], or compared to other countries [39], but it still represents a significant risk for AMR emergence. Indeed, studies exploring the impact of feeding milk containing antimicrobial residues to calves demonstrated the selection of antimicrobial-resistant bacteria [40, 41].
As a result of the initiatives and awareness-raising actions proposed by the government and international organisations, antibiotic sales in livestock seemed to decrease over the last years. The most recent version of the UK Veterinary Antibiotic Resistance and Sales Surveillance (UK-VARSS, 2021) reported a reduction of 68% in cattle injectable HP-CIAs between 2016 and 2020 [42]. Almost all participants of this study (90%) reduced their AMU in the last years, indicating a more promising result than Jones et al [11]. Nevertheless, many farmers believed that reducing AMU was complicated, with limited facilities and limited knowledge being the main barriers. Also, they indicated profitability as one of the main concerns related to lower medicine usage. Other studies reported that economic constraints, tight profit margins, and inadequate facilities hinder farmers from improving herd health and reducing AMU [13, 17, 21]. Since producers may be discouraged by financial limitations, advisors need to demonstrate the effectiveness of simple, low-cost hygiene/management practices to prevent infections. Also, economic rewards and incentives for low antimicrobial users may motivate farmers to implement new strategies and optimize AMU [43].
Regarding future intention, 87% planned to decrease antibiotic consumption in the next five years. Once more, this proportion is higher compared to previous UK studies [11, 12], suggesting that recent antimicrobial stewardship campaigns had positive impacts on farmers’ intentions.
Understanding farmers’ attitude toward AMR is essential to implement specific strategies and achieving responsible antimicrobial usage. Previous research showed that positive attitudes towards SDCT and AMR were related to whether farmers would implement SDCT [33], and with the intention to reduce AMU [11].
In this study, most respondents endorsed the importance of decreasing AMU on UK dairy farms. However, this finding conflicts with the fact that only half of them agreed on the over-reliance on antimicrobials or expressed concerns about antimicrobial resistance. Then, for some farmers, there may be a mismatch between the intention to reduce AMU and the actual recognition of over-using antimicrobials. As suggested by other studies in the UK [13, 44], this may indicate that dairy producers do not perceive AMR as a current risk for their reality or something they have already experienced. Instead, they may be more concerned about other daily challenges, such as welfare, poor housing conditions, and productivity [30]. It is difficult to convince farmers to change their working routine if they believe their practices are appropriate or ignore the adverse effects of the overuse of antimicrobials. Raising awareness about the potential risk of AMR for their business is necessary to influence farmers’ behaviour. Indeed, we found that farmers lacking knowledge regarding AMR meaning expressed fewer concerns around AMR, as likely they considered AMR distant from their everyday life.
Respondents generally agreed on the association between AMU and AMR in livestock. However, they were more doubtful about the potential impact on global health. Scepticism about the contribution of AMU in cattle to human AMR was reported in other studies [13, 26, 28]. Renunciation of responsibility can be an important barrier to improving AMU on dairy farms.
Many farmers in this survey believed that more training is essential for reducing antimicrobial usage. Self-efficacy, or perceived behavioural control, depends on a person’s belief that they are able to accomplish a task [30, 31]. If farmers believe in having the knowledge and the skill to achieve reduced AMU, they are more likely to overcome habitual behaviour and implement new strategies. Thus, this study highlights the importance of providing producers with the tools they need to reach responsible AMU, such as regular training, guidance, and review of the outcomes.
The attitude of farmers is generally influenced by their demographic factors, experiences, and economic background. In a recent study, veterinarians reported knowing in advance whether a farmer would react as an advice-taker (positive), or advice-leaver (negative), based on his/her personality [16]. Overall, we found a wide variety of attitudes among respondents. This suggests that veterinarians and advisors should consider the level of awareness and ownership before recommending farm interventions. Tailored strategies would be more beneficial to change the mindset than a generic approach.
Several limitations may have influenced the results of this study. Self-selection bias due to voluntary participation in the online survey was possible, with overrepresentation of farmers with a particular interest in the topic or a higher educational level. Participants not involved in antimicrobial administration may not have been fully aware of the practices and AMU on the farm. In the questionnaire, social desirability bias may happen when respondents give answers that are socially accepted but that do not guarantee the truth. In this study anonymity was guaranteed, so social desirability bias was likely limited. Despite the response rate is low, as expected for non-random surveys online, the sample represented a good proportion of the targeted group (Scottish dairy farmers).
This survey represents the first time that practices and knowledge around AMU and AMR have been investigated in the Scottish dairy sector. The results show that much progress has been achieved in terms of AMU and best practices implementation. Yet, motivation and attitudes towards AMR varied among farmers. Drivers and barriers for responsible AMU identified in the study may help veterinarians and advisors tackle AMR in dairy herds.