Perceptions on Economic Feasibility of Sustainable Roundworm Control Practices in Grazed Livestock— A Short Survey Among European Farmers and Veterinarians

1. Introduction

Gastrointestinal nematodes (GIN) remain one of the most significant challenges to the health, welfare, and productivity of grazing ruminants globally. Traditionally, control has relied heavily on the frequent and prophylactic use of anthelmintics; however, the rapid emergence of anthelmintic resistance (AR) in many GIN has rendered this approach increasingly unsustainable [1]. It is crucial for the European livestock sector to undergo a ‘green transition’, seeking sustainable worm control (SWC) approaches that maintain animal performance while minimizing use of chemical products . However, despite the growing availability of SWC approaches, their adoption tends to remain uneven across farmers. Lack of data on the economic impact of SWC approaches is considered an important barrier to their implementation [2]. Additionally, farmers often abandon long-established worming routines only when both economic analyses and scientific evidence clearly demonstrate the value of alternative strategies, a point emphasized by [3]. Similarly, Howell et al. (2025) identify “time and cost” as practical, real-world barriers hindering the uptake of sustainable GIN control approaches among farmers [4].

It is important to understand the factors that influence key stakeholders’ decision making in considering adoption of SWC practices and whether they consider the practices to be credible, acceptable and actionable. Hence, this paper provides more data on this aspect by conducting a short European wide survey on the perceptions of economic feasibility. Below we briefly introduce the different SWC approaches that were evaluated in the survey, followed by the concrete objectives of this paper.

Current research has identified a diverse ‘toolbox’ of promising SWC approaches such as targeted (selective) treatment TST, Targeted Treatment (TT), grazing management, selective breeding, vaccination, biological control, use of diagnostics, nutrition including bioactive forages [5]. While for most SWC approaches, proof of concept has been delivered that they can effectively reduce worm burdens while reducing anthelmintic use; their implementation in livestock systems remains limited [5]. Among all the options, TT and TST may be the most thoroughly validated, focusing on maintaining parasite “refugia”- populations of worms unexposed to drugs to slow the development of resistance [6]. TST involves treating only specific individuals based on diagnostic indicators, whereas TT targets the whole group only when specific risk thresholds are reached [7,8]. TST is known to reduce anthelmintic reliance, recent meta-analyses reported that a statistically significant but small production cost must often be accepted in terms of animal performance [9].

Other complementary sustainable control approaches include grazing and direct feeding of bioactive plants and/or plant derived compounds such as condensed tannins and saponins provided through plant multispecies [10], bioactives (additives given on top of the normal diet that contain microorganisms, enzymes, or other bioactive compounds [11,12]. Additionally, feeding livestock with agro-industrial by-products with anthelmintic properties such as pomegranate peel, grape pomace and hazelnut skins that also exhibit richness in condensed tannins and other polyphenols, which have been shown to inhibit GIN larval development and reduce parasite fecundity [13]. Furthermore, while bioactive plants can interfere with the nematode life cycle, reduce worm burden, and indirectly impact host immunologically mediated responses, their efficacy can be influenced by variations in the actual concentrations of bioactive components due to factors such as climate, processing, and time of harvest/feeding [5,10].

Biological control agents like the nematode-trapping fungus Duddingtonia flagrans reduce the number of infective larvae on pasture [14,15,16], but efficacy can be influenced by climatic conditions. In terms of other grazing management, specific strategies such as mixed grazing (two or more animal species graze together on the same pasture) have been shown to improve production performance in goats and cattle [17], yet economic modeling indicates that the financial return varies significantly between farms, requiring site-specific evaluation [18].

Conducting quarantine and strategic screening involves isolating new, or returning stock, to prevent the introduction of infectious agents, especially resistant GIN, into the existing herd or flock. This follows a specifically recommended sequence: isolate, test, treat quarantine turnout, test again, and merge [19,20]. Selective breeding of animals resistant to or resilient to GIN infections offers a clear long-term productivity advantage [21,22]. With very few nematode vaccines available in the field, and only marketed in certain countries, there is a significant lack of data regarding their effects on long-term animal productivity or farm profitability in Europe [23].

A significant gap remains regarding the practical adoption of SWC practices [24]. Ultimately, the feasibility of these methods depends on the perceptions of farmers and veterinarians; understanding their beliefs regarding the reliability and day-to-day manageability of these practices is essential to ensure their long-term implementation. Furthermore, the economic burden of worm control is not uniform across European countries, sectors, and individual farms. Variations in anthelmintic pricing, livestock margins, labor costs, and regional agricultural policies create diverse financial contexts [25]. These factors shape how stakeholders evaluate the affordability and perceived value of SWC approaches, leading to distinct regional perceptions across Europe.

To acquire more insights into the perceptions of farmers, veterinarians and other stakeholders on the economic feasibility of SWC approaches, a survey was organized as part of the Horizon Europe Thematic network - Sustainable Parasite Control (SPARC). The initial data of this survey will later be complemented and validated through animal data currently being collected at pilot farms from across Europe [5].

There were two objectives: (i) to assess the level of endorsement of various SWC approaches among key stakeholders, including farmers, veterinarians, and farm advisors; and (ii) to understand the perceived economic burden and feasibility of these practices. Generated insights can support the future focus and further development of SWC approaches across Europe.

2. Materials and Methods

2.1. Survey Design

A survey was administered electronically between February to June 2025 to capture information on perceptions and opinions of veterinarians, farmers and other stakeholder of ruminant health on various SWC approaches and the economic outcomes associated with their implementation at farm level. The survey was disseminated through the Horizon Europe Thematic Network -SPARC, complemented by additional countries through the network of the COST Action ENVIRANT. Each participating country was represented by a designated national contact person. These national representatives were responsible for further distributing the survey within their respective livestock sectors via established local networks. Inclusion criteria required respondents to be active stakeholders within the ruminant livestock sector in the participating countries. Eligible participants included farmers, veterinarians, farm advisors, and researchers.

Participation in this survey was voluntary and anonymous, and all respondents were informed that there were no “right” or “wrong” answers and that their individual responses would not be evaluated. The following disclaimer was provided to all participants: “Participation in this survey is completely voluntary. All information you provide will be stored securely and will not be shared with anyone outside the research team. You will not be identifiable in any data collected from this survey”. The survey form consisted of 8 questions and three sections: (1) stakeholder information, capturing demographic and professional characteristics; (2) budget allocation, focusing on financial allocations directed toward worm control; and (3) an assessment of the perceived economic benefits associated with investing on seven selected SWC practices.

The study questions focused on the opinions of incurred costs in treating the animals and understanding of the various SWC practices. It is worth to note that participants were not asked to describe the specific strategies they use on their own farms; rather, they were asked to provide their general opinions about these topics.

To measure stakeholder perceptions, the survey utilised a 4-point scale (Strongly Disagree, Disagree, Agree and Strongly Agree). An additional ‘I don’t know’ category was also provided to ensure data accuracy and avoid forced responses.The survey was developed using Microsoft Forms (Microsoft 365) and translated into 11 languages (English, Dutch, French, Italian, Spanish, Polish, Greek, Latvian, Romanian, Lithuanian and Turkish) and distributed across 13 countries.

The questionnaire was designed to be completed online within 3–6 minutes, although there was no time restriction imposed. To maximize stakeholder outreach, an additional dissemination campaign was carried out across the SPARC network using a wide range of channels, including SPARC National Contact Points, SPARC WhatsApp groups, social media, farmer events, and the SPARC EU webinar. A detailed table summarizing all survey items/questions and their corresponding response options is presented in the Supplementary File.

2.2. Data Analysis

During data cleaning, cases with incomplete responses or noticeable anomalies were addressed. Descriptive statistics were computed to characterize the study population and summarize stakeholder responses. Counts and percentages were calculated for categorical variables including respondent role, age, gender, country of origin, and perceived worm control cost proportions.

An ordinal logistic regression model was employed using the R package ‘ordinal’ to investigate factors associated with the perceived proportion of worm-control costs within respondents’ animal health budgets. The dependent variable consisted of four ordered categories (“<25%”, “25–50%”, “50–75%”, and “>75%”), reflecting increasing relative cost burden. Predictor variables included stakeholder roles, gender, age group, and country. Model coefficients were expressed as odds ratios (ORs) with corresponding 95% confidence intervals (CIs).

Perception on economic outcomes for seven SWC approaches was firstly reported visually for the two largest stakeholder groups – farmers (42.8%) and veterinarians (43.6%). The percentage of ‘Agreement’ reflects the combined frequency of ‘Agree’ and ‘Strongly Agree’ responses for each strategy. To assess overall receptiveness, a composite SWC Attitude Score was then derived by averaging the numeric responses for the seven individual practices (coded from 1 = ‘Strongly disagree’ to 4 = ‘Strongly agree’), where ‘I don’t know’ responses were excluded to ensure the score reflected active stakeholder opinions. Internal consistency of these seven approaches was evaluated using Cronbach’s alpha (α = 0.81). Associations between the SWC Attitude Score and respondent characteristics were examined using multiple linear regression with robust (HC3) standard errors. The same reference categories were used as the first regression model described above. Coefficients were reported as mean differences with 95% CIs.

All statistical analyses were conducted using R software (version 4.4.1; R Core Team, Vienna, Austria).

3. Results

3.1. Descriptive Statistics

A total of 1,261 respondents completed the survey (Table 1). Participants represented a wide range of stakeholder groups, including farmers (42.8%), veterinarians (43.6%), researchers (7.1%), farm advisors (3.1%), and other professionals (3.4%) involved in livestock production and animal health. Respondents were distributed across 13 European countries, with the largest proportions from Türkiye (35.7%) and Italy (14.1%), followed by Belgium (9.8%), Latvia (8.3%), Greece (7.5%), and Romania (6.9%).

Most respondents were aged between 18 and 60 years. The largest age group was 18–30 years (30.8%), followed by 31–40 years (27.0%), 41–50 years (17.8%), and 51–60 years (14.9%).

Stakeholder composition varied significantly across countries (Figure 1). Belgium, Poland, Romania, and Ireland were predominantly represented by farmers (cattle, sheep and goats combined) (>70%), whereas Türkiye and Latvia consisted mainly by veterinarians (> 64%).

3.2. Perceived Proportion of Worm-Control Costs

Overall, 56.7% of respondents disagreed with the statement that the costs of diagnostic testing are higher than the benefits, whereas 30.1% agreed and 13.2% selected ‘I don’t know’. However, perceptions varied considerably by country (Figure 2). Respondents in France, Greece, Lithuania, and the Netherlands were highly positive, with over 75% disagreeing that costs outweigh benefits. Conversely, Türkiye (44.9%) and Romania (38.1%) showed the highest proportions of respondents agreeing with the statement that cost exceed benefits. Belgium showed more divided opinions with 37.8% disagreeing that costs outweigh benefit and 32.8% agreeing with the statement. Across all countries, “Strongly agree” was consistently the least frequent response.

Marked regional and stakeholder differences were observed in the perceived proportion of animal health budgets devoted to worm control (Figure 3). Across all regions, most respondents reported costs below 50%, although higher perceived cost burdens were reported in Romania.

Worm-control cost burden differed across respondent characteristics (Table 2). Compared with farmers, farm advisors were significantly less likely to report higher cost proportions (OR = 0.32, 95% CI: 0.10–0.85), while no significant differences with farmers were observed for veterinarians (OR = 0.90, 95% CI: 0.66–1.24) and researchers (OR = 0.57, 95% CI: 0.25–1.23). Male respondents reported lower cost proportions than females (OR = 0.70, 95% CI: 0.51–0.96). Marked country-level differences were observed, with respondents from Romania (OR = 9.58, 95% CI: 4.98–18.83), Italy (OR = 3.72, 95% CI: 2.09–6.77), France (OR = 3.16, 95% CI: 1.47–6.82), and Greece (OR = 2.63, 95% CI: 1.34–5.25) reporting significantly higher worm-control cost proportions compared with the baseline. No significant associations were found with age.

3.3. Perception on Economic Outcomes for Seven Major SWC Practices

Figure 4 illustrates how the two key stakeholder groups (largest stakeholder groups in the survey responsiveness), farmers (42.8%) and veterinarians (43.6%), perceived the economic feasibility of various SWC approaches. The most widely recognized method was the sustainable use of anthelmintics, with agreement from 94% of veterinarians and 88% of farmers. This was closely followed by quarantine and strategic screening (supported by 92% of the veterinarians and 83% of farmers) and grazing management (supported by 87% of veterinarians and 77% of farmers).

A majority of the respondents also agreed with other SWC approaches (bioactive feed supplements, selective breeding, multispecies/bioactive pastures and vaccination), although at somewhat lower percentages.

Responses to the seven SWC strategies were aggregated into an overall SWC Attitude Score, representing respondents’ mean level of agreement across practices. The index demonstrated good internal consistency (Cronbach’s α = 0.81).Based on the SWC Attitude Score, veterinarians had a slightly more positive attitudes towards SWC practices than farmers (β = 0.07, 95% CI: 0.002–0.13) (Table 3); male respondents lower than females (β = −0.11, 95% CI: −0.17 to −0.05); and respondents aged 51–60 years lower than those aged 18–30 years (β = −0.10, 95% CI: −0.19 to −0.01). Strong cross-country differences were observed, with respondents from Greece, Italy, Poland, Romania, Spain, and Türkiye reporting higher SWC attitude scores than those from Belgium (all p < 0.01). Overall, the model only explained a low proportion of variance in attitudes (Adjusted R² = 0.06).

4. Discussion

This study sought to collect initial stakeholder perceptions regarding the economic feasibility of SWC approaches via a short survey across Europe. GIN are widely recognized as a major constraint on ruminant health and productivity in Europe [18], although our needs-assessment results show that the level of awareness varies between countries. As indicated by reports from the SPARC project [26], farmers frequently encounter challenges in translating SWC approaches into practice. These challenges may often be attributable to constraints such as time, labor availability, limited diagnostic access, and the perceived complexity of SWC tools [26]. In addition, the existence of communication gaps between advisors and farmers, the fragmentation of knowledge-exchange pathways, farm-size, and the lack of clear, tailored, region and enterprise (farm sizes)-specific guidelines act as obstacles to wider behavioral [5,27].

In our principal findings, the study showed substantial contrast between the theoretical appreciation of SWC approaches (Figure 4) and the perceived budget dynamics associated with diagnostics (Figure 2). Firstly, diagnostics were generally viewed as affordable. This could indicate that their adoption is often motivated more by sustainability considerations than by direct economic motives. A similar study [28], reported that while anthelmintics are typically used for economic reasons, the decision to employ diagnostic tools is more closely associated with long-term sustainability goals, suggesting that cost is not the primary factor determining diagnostics uptake [28]. This suggests that existing financial pressure may increase stakeholders’ desire for better control outcomes. In this context, diagnostics could be perceived as a short-term expense rather than a long-term cost-saving measure. A previous study similarly indicated that selective anthelmintic treatment can achieve similar economic results as whole herd treatment [8], the immediate labor and testing costs often discourage uptake in systems with tighter profit margins [29].

Secondly, the findings confirmed that roundworms remain a major animal health concern across Europe (Figure 3). This aligns with recent assessments showing that parasitic worm infections continue to impose substantial economic burdens on ruminant production systems, with annual sector-wide losses estimated at over €1.8 billion in Europe [5]. Differences between countries in the perceived importance of roundworms may relate to the differing prominence of the sheep sector, where GIN are consistently recognized as primary health challenges [5].

Thirdly, the observation that cost is not considered the main barrier to SWC implementation suggests that other constraints influence farmers’ willingness or ability to adopt evidence-based parasite management strategies. Similar studies stakeholder surveys conducted across Europe highlight barriers such as lack of time, complexity of messages, insufficient knowledge exchange, and limited/unclear practical guidance on sustainable approaches, all of which can hinder diagnostic uptake and broader SWC adoption [30]. Hence, future studies should focus on understanding and addressing these non-economic barriers, e,g. behavioural factors, perceived norms and practical feasibility of SWC approaches.

Beyond diagnostics, our results reveal a hierarchy of acceptance for other SWC approaches. TST, grazing management and quarantine strategies were among the most positively viewed interventions. This could be because they can be applied immediately and do not rely on approaches which take a long time to implement (e.g., selective breeding), are not readily available (vaccines) or may have a variable efficacy (bioactive compounds). This is supported by previous studies suggesting that farmers are more likely to adopt strategies that integrate seamlessly into their existing workflows and management routines [29]. In contrast, the use of bioactive plants and nematode-trapping fungi received the highest uncertainty answers (“I don’t know”), particularly in western European countries. Although these methods show promise in controlled trials [10,31], the observed stakeholder hesitation may reflect lack of knowledge of these control methods, concerns regarding their variable efficacy under field conditions, and/or the limited availability of commercial products in these regions. Nonetheless, also for these more variable approaches, the overall perception was positive (>60%), indicating that they also have a good place in the European basket of SWC options.

A consistent trend observed across all regions was the divergence in attitudes between professional advisors and farmers. Veterinarians displayed significantly higher acceptance of knowledge-intensive practices than farmers, although the difference was small (8%). A higher positive attitude of veterinarians may be logical as SWC will require more in depth knowledge on parasite epidemiology and control, than traditional control based on the regular administration of anthelmintics on fixed calendar days. SWC approaches may therefore need more specialist advice and put the veterinarians in a key position to drive SWC adoption [18,29]. However, a disconnect is evident: farm advisors (n=40) were over three times less likely than farmers to report that worm control accounts for a high proportion of their animal health budget. This observed discordance between farmers and advisors is consistent with earlier findings [32], who reported that the adoption of targeted (selective) treatments is influenced not only by economic considerations but mainly by practical challenges that vary across stakeholders.

Demographic factors also played a subtle but significant role in shaping perceptions. Male respondents reported both lower cost proportions and lower overall SWC Attitude Scores compared to females. Furthermore, older respondents (51–60 years) held fewer positive attitudes towards SWC than those aged 18–30. As previously demonstrated in related studies, gender and age-related differences in farmer attitudes and behaviors have been identified in the context of sustainable parasite control adoption [29]. These variations highlight the complexity of stakeholder attitudes, suggesting that sociological drivers play a key role and warrant specific investigation into future sustainable farming research.

This study reports stakeholder perceptions and finds that economic constraints may not constitute the primary barrier to the adoption of SWC approaches. Future field studies could validate these perception-based findings by implementing and testing different SWCs while accessing farm performance data [25]. Simultaneously, other challenges which may act as important barriers to the uptake of SWC should be further investigated. These may include challenges related to low awareness, practical feasibility, unclear or conflicting operational guidance and contradictory advice by different farm advisors [2].

The primary limitation of this study is that the participant sample may not fully reflect the broader population. Although the questionnaire was translated into local languages to enhance accessibility, participation still required consistent internet access and a minimum level of digital literacy, which may have excluded individuals lacking these resources. The study is also subject to self-selection bias, as respondents who chose to participate voluntarily may differ systematically from those who did not, particularly with respect to interest, motivation, and the strength of their views. Additionally, demographic imbalances may be present, such as the overrepresentation of younger respondents compared with older individuals or unequal gender distribution. Populations residing in areas with limited connectivity are also likely to underrepresented.

Lastly, the overall hurdles may be most effectively addressed via bottom-up approaches where farmers, veterinarians, and other advisors share experiences, test solutions and co-develop advice/recommendations/solutions together. The SPARC project aims to establish national and regional Communities of Practice (CoP) with this aim [33]. A central component of this structure is the recruitment of SPARC ambassadors – influential stakeholders such as key opinion leading farmers or veterinarians – who also facilitate horizontal knowledge transfer. By leveraging these ambassadors to disseminate practical, locally adapted materials within their own networks, such initiatives can bridge the gap between scientific efficacy and on-farm reality, maximizing outreach and fostering a self-sustaining culture of sustainable control.

5. Conclusion

The study demonstrates that a majority of stakeholders across Europe perceives SWC approaches as economically feasible, indicating that cost is unlikely to be the primary barrier to adoption. Diagnostics are also generally viewed as beneficial, suggesting a substantial scope for increasing their uptake. However, notable differences between countries highlight the need for adapted, region-specific approaches rather than uniform recommendations. Moving forward, field-based evaluations are essential to confirm these perceptions under real-world conditions, while addressing non-economic barriers – such as practical implementation challenges and communication barriers – through collaborative structures, such as the SPARC Communities of Practice. The latter aims to support sustainable, locally grounded, farmer-led and veterinarian-supported worm control strategies.