Use of Antibiotics. In Food-Producing Animals: A Survey of Ontario Veterinarians Involved with. Food-Producing Animal Practice

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1 Use of Antibiotics In Food-Producing Animals: A Survey of Ontario Veterinarians Involved with Food-Producing Animal Practice September October 2014 A Component of the College of Veterinarians of Ontario Growing Forward 2 Project: Ontario Veterinary Stewardship of Antimicrobial Use In Food-Producing Animals This project is funded in part through Growing Forward 2 (GF2), a federal-provincial-territorial initiative. The Agricultural Adaptation Council assists in the delivery of GF2 in Ontario. The views expressed in the report or materials are the views of the survey participants and do not necessarily reflect those of the governments of Canada and Ontario.

2 Table of Contents Executive Summary... 3 Purpose of Survey... 5 Development of Survey Content... 5 Overview of the Survey Instrument... 6 Section One... 6 Sections Two through Seven... 6 Section Eight... 7 Section Nine:... 7 Sample Selection... 7 Timelines and Process... 7 Analytic Methods... 8 Characteristics of Respondents... 8 Results... 9 Source of antibiotics and frequency of use for important conditions and situations... 9 Factors influencing decision to use antibiotics Factors influencing choice of antibiotic Frequency of use of antibiotics in an extra-label manner Reasons for use of antibiotics in an extra-label manner Control over antibiotic use on farm Written Protocols Role in establishing written protocols for antibiotic use Role in implementing written protocols for antibiotic use Role in ensuring compliance with written protocols for antibiotic use Trends in antibiotic use in last five years Potential for reduction in antibiotic use if mandated Opportunity for reducing antibiotic use Most commonly used antibiotics Impact of species-specific food safety/quality assurance programs Importance of various sources of information on use of antibiotics Impact of various factors on the prudent use of antibiotics Link between antibiotic use and resistant bacteria Perceptions about changes and restrictions to implement in Ontario Conclusions Tables Figures

3 Executive Summary The College of Veterinarians of Ontario Growing Forward 2 (CVO GF2) project was developed to explore the current practices and views of Ontario veterinarians on the issue of antibiotic use in food-producing animals. Through a process involving a background review, a survey, facilitated discussions, and consultation with stakeholder groups the project will produce recommendations regarding the veterinary stewardship of antibiotic use in Ontario. This report is one component of the overall study and concerns the electronic survey of Ontario veterinarians involved in foodproducing animal practice that was conducted in the fall of Of the 335 respondents used in the analysis, the largest group were involved with dairy cattle, and the smallest group with veal calves. Very few respondents spend all of their time dealing with one specific species. Those veterinarians working primarily on one species over 75% of the time are largely found in the dairy, poultry and swine groups. In addition to sections that collected demographic information and general information and recommendations on antibiotic use in food-producing animals in Ontario, the survey included six species specific (i.e. beef cattle, dairy cattle, poultry, sheep/goats, swine and veal calf) sections that investigated aspects of antibiotic use in those species. Many significant differences were seen between the species groups of veterinarians; however, very few differences were identified based on demographic data. With respect to the treatment of selected prevalent conditions in each species, the survey investigated the frequency with which antibiotics were used for each condition. In each species group, there were significant differences in the frequency of antibiotic use between the conditions. As far as the source of these antibiotics, the results differentiated between those obtained from any source (provided through a veterinarian or obtained elsewhere) versus those obtained elsewhere without a prescription. There were conditions in each species group in which significantly more antibiotic was obtained from all sources versus elsewhere without a prescription. Decision making around whether or not to use antibiotics in a given situation, and which antibiotic to use, was explored. History and clinical picture of the individual animal was the most important factor influencing the decision on whether to recommend antibiotics. Comparing across species, the history and clinical picture of the animal, owner preferences and demands, and withholding/withdrawal times were of significantly different importance between the species groups. History and clinical presentation of the herd was the most important factor influencing the decision choice of which antibiotic to use. Comparing across species, the cost of antibiotics, appropriate species and indication label, route of administration, withholding time, and culture and sensitivity results were of significantly different importance. Regarding extra-label drug use, most respondents reported using antibiotics in an extra-label manner at some level. Approximately one fifth of respondents reported using antibiotics often in an extra-label manner. However, the largest proportion of respondents reported using antibiotics in an extra-label manner only rarely, which was significantly higher than the other categories. Sheep/goat respondents most frequently used antibiotics in an extra-label manner due to the fact that they were treating species that differed from those included on the label. 3

4 The influence of veterinarians regarding the use of antibiotics on farms was explored through a series of questions. While over half of respondents reported that they felt they often had control over antibiotic use on farms that they serve, approximately 40% reported feeling only occasionally or rarely in control over antibiotic use. In addition, 43% reported that they often have a role in establishing written protocols, with dairy and swine respondents reporting the most significant role. Whereas, 39% of respondents reported they often have a role in implementing written protocols with swine respondents reporting the most significant role. Finally, 31% of respondents reported that they often have a role in ensuring compliance with written protocols, with poultry respondents reporting the most significant role. Regarding trends noted in antibiotic use over the last five years, the findings were quite variable, with just under half of respondents reporting no trend. Approximately three quarters of respondents agreed that there is potential to reduce the amount of antibiotics used in practice in Ontario if it was mandated. Among beef respondents, metaphylactic treatment was identified as the most important situation where antibiotic use could be reduced. Dairy respondents felt that selective/targeted treatment was the most important opportunity to reduce use. Poultry, sheep/goat and swine respondents all felt it was most important to create a prescription only system, where antibiotics are only available with a veterinarian prescription. Lastly, veal respondents felt the most important opportunity to reduce antibiotic use was to improve management and housing and focus on prevention, rather than treatment. The majority of respondents felt that there was somewhat of a link between the use of antibiotics in food-producing animals and an increasing prevalence of resistant bacteria with the potential to have a negative impact on human health. Respondents were asked to list the three most commonly used antibiotics in their practice. These data were grouped according to product type, as well as categorized according to the Health Canada Categorization of Antimicrobials based on Importance in Human Medicine. The majority of the most commonly used antibiotics are from Categories II and III, with a small number from Category I. Across most species groups, the most commonly used antibiotics are in the penicillin and tetracycline groups. In beef and veal practice, flurofenicols were also commonly used. In dairy practice, use of the ceftiofur group (Category I) of antibiotics was common. Poultry veterinarians reported using the penicillin group most commonly, followed by the tetracyclines and Bacitracin. Sheep/goat veterinarians reported using the penicillin group, tetracyclines and trimethoprim products most commonly. veterinarians selected the penicillin group and tetracycline products, as well as ceftiofur products most frequently. veterinarians reported using macrolides, tetracyclines and flurofenicols most frequently. All species groups have food safety/quality assurance programs that potentially impact antibiotic use on farms. A list of potential impacts was provided and respondents ranked them as to the impact they have achieved. The most significant impact was reported in improved record keeping on farms, followed by improved dialogue between veterinarians and producers regarding antibiotic use, and increased producer awareness of antibiotic residues. Veterinarians can access many sources of information regarding antibiotic use. Nearly half of respondents ranked formal continuing education as a very important source for information. CgFARAD was ranked as the second most important information source, followed by communications from pharmaceutical manufacturers. The responses for the importance of various sources of information about antibiotics were significantly different among species groups. 4

5 Respondents were questioned about the importance of various factors that may impede prudent use of antibiotics. The majority of respondents reported that the sale of antibiotics through lay outlets was the most important factor impeding prudent antibiotic use, followed by the importation of antibiotics for own use by producers and the importation and usage of Active Pharmaceutical Ingredients (APIs). In every species group, the sale of antibiotics through lay outlets and imported antibiotics for own use by producers were viewed as the factors most significantly impeding prudent use of antibiotics. With respect to changes and restrictions to antibiotic use that should be implemented in Ontario, eliminating the own use loophole was the most popular option, with over 90% of respondents agreeing. Elimination of the sale of antibiotics through lay outlets and the mandatory training for producers on the judicious use of antibiotics were the second and third most popular. Over 50% of the respondents also agreed that changes should include restricting antibiotic availability to a prescription only system, a voluntary reduction in antibiotic use by producers, a reduction in the use, prescribing and dispensing of antibiotics by veterinarians, a mandatory continuing education component for veterinarians related to use, prescribing and dispensing antibiotics, a ban on labeling of antibiotics for growth promotion and production purposes, and regulation and review of antibiotic use on farms through a review of records. In conclusion, this survey provided information on the current practices, views and recommendations of Ontario veterinarians involved in food-producing animal practice related to the use of antibiotics. Purpose of Survey The survey was designed to explore the current practices, views, and recommendations of Ontario veterinarians involved in food-producing animal practice related to the use of antibiotics in foodproducing animals. For the purposes of this survey, food-producing animals included beef cattle, dairy cattle, poultry, sheep/goats, swine and veal calves. The survey did not include horses, fish or rabbits or any other animals that are raised for food. The term antibiotic was used throughout the survey to avoid potential misunderstanding that could arise from the term antimicrobial. This approach was employed, since antimicrobials could include antiparasitics, antifungals, antivirals and non-drug antibacterial preparations, such as iodine and formaldehyde, in addition to antibiotics. Development of Survey Content A comprehensive review of selected published literature and other background information was conducted in order to identify areas of concern and interest related to the use of antibiotics in foodproducing animals. This information was used to create an initial draft of questions related to the general aspects of using antibiotics, as well as questions specific to antibiotic use in each particular species. These questions were subsequently entered into, and formatted for, the survey software FluidSurveys. 5

6 Following another series of reviews, the questions were edited in the electronic medium and Draft Survey I was produced. A specifically selected group of 6 individuals were chosen and requested to complete Draft Survey I. These individuals were provided electronic access to the FluidSurveys survey instrument. Following their completion of the survey, each member of this group was interviewed individually to probe their interpretation of the questions, the clarity and appropriateness of the intent, and any concerns with the content. Based on the detailed input that was received, further changes were made to create Draft Survey II. Draft Survey II was circulated through electronic access to members of the CVO GF2 Project Advisory Group, who were invited to provide feedback. This feedback led to further changes to the survey to produce the final CVO GF2 Project Survey. Overview of the Survey Instrument A total of 105 questions were designed to accomplish the purposes of the survey. The questions were divided amongst nine sections. Section One Section one was designed to ensure that all respondents were involved in food-producing animal practice, as well as to determine their type of involvement (practitioner and/or advisor) and the breakdown of their involvement by species. If a respondent was not involved in food-producing animal practice or did not provide advice to food-producing animal practitioners, the respondent was taken directly to the end of the survey and no further information was gathered. An initial question in this section determined how the respondent was involved in food-producing animal practice: either as a practitioner or as one who advises practitioners. It was important to include both groups as they are both knowledgeable about the subject matter and both would have an impact on antibiotic use. The second question determined the breakdown of the time spent on food-producing animals by species. At this point, the respondent was given the option of limiting their response to two species, if they were involved in activities with more than one. This approach was used to alleviate the problem of multi-species respondents being faced with responding to more than two species sections, as each additional species would significantly increase the time required to respond to the survey. Sections Two through Seven The questionnaire then flowed through the six various species groups in alphabetical order: beef cattle, dairy cattle, poultry, sheep/goats, swine and veal calves as determined by the species selection with questions being coded BC, DC, P, SG, S and V respectively. These sections were identical with the exception of the reference to major specific conditions or situations involving the particular species, and the reference to food safety/quality assurance programs impacting particular species. 6

7 Questions probed the use and source of antibiotics on farms, criteria utilized to decide whether or not to recommend antibiotics and which antibiotic to use, prevalence of extra-label drug use and the reasons for it, veterinarian control over antibiotic use on farms, any observed trends in the use of antibiotics, views on the potential for reduced antibiotic use if mandated, the impact veterinarians felt they had on protocols for antibiotic use and the impact of species specific food safety/quality assurance programs. Section Eight Questions in this general section applied to all respondents, regardless of species treated. The questions were designed to determine sources of information on antibiotic use, to explore factors believed to be impeding prudent antibiotic use, to understand how veterinarians view the link between use of antibiotics in food-producing animals and antibiotic resistance, and changes that should be implemented in Ontario regarding antibiotic use. Section Nine: Finally, some demographic data was collected in the last section. Respondents were given the opportunity to include any further comments at the conclusion of the survey. Sample Selection Members of the College of Veterinarians of Ontario (CVO) are required to provide information to the CVO at the time of registration, as well as each year at the time of annual renewal of one s registration. This information, stored in the CVO electronic database, includes the species with which members have indicated they are involved. The database also includes and mailing addresses for all members. All members with general, academic or restricted licenses that indicated involvement in beef, dairy, swine, sheep/goat and/or poultry were included in the mailing list. Those with general nonresident, post graduate resident, educational and public service licenses were excluded from the mailing list. Timelines and Process A total of 756 veterinarians were invited to participate in the survey: 746 were sent an on September 10, 2014, which directed them to a link for the survey and 10 hard copies, with a covering letter were mailed to those for whom CVO did not have a valid address. Respondents who received an electronic survey who requested a hard copy were provided one by mail. reminders were provided to non-respondents. Once an individual responded, they no longer received a reminder message. The reminder messages were ed on September 22nd, October 1st, 7th, 14th, 15th, 16th, 17th, 18th and 20th. Additionally, on October 21, reminder s were sent to 82 addresses that were shown as starting the survey but that did not complete it. A total of messages were sent requesting survey completion. There were 53 who viewed the survey but did not begin to complete it. All the others who did not complete did not view 7

8 the survey. A small number of people responded through to say that they did not treat foodproducing animals. These responses were recorded and their addresses were deleted from distribution. The survey was closed on October 22, 2014 after being open for 6 weeks. A total of 466 responses were received, representing a 61.6% response rate. Analytic Methods Survey results were exported into a Microsoft Excel spreadsheet, where all data were cleaned (i.e. scanned for incorrect entries and missing data) and coded (i.e. converted from text descriptors/labels to numbered form). The cleaned and coded dataset was then imported into Stata 12.1 IC for Mac, where further analyses were conducted. Given the use of Likert scale questions to measure respondent answers, nonparametric statistical approaches were used to assess differences between groups. Medians, and first and third quartiles are provided to summarize all data. Comparisons between two medians were completed using a Wilcoxon Mann Whitney Test. Comparisons between more than two medians were completed using a Kruskal-Wallis test. Comparisons between the distributions of two or more categorical variables were conducted using Fisher s exact test. A significance level of p = 0.05 was used for all analyses. Univariable ordered logistic regression was used to assess associations between demographic factors (primary species served, number of veterinarians in the practice, number of locations for each practice, age, year graduated, qualifications, and geographic location served) and outcomes of interest. Lastly, open-ended responses were coded (i.e. summarized into points based on content), compared, and categorized, with frequency counts provided to express the most common responses. Follow up comments provided by respondents for specific questions were independently reviewed, coded, and categorized. Characteristics of Respondents Of the 466 respondents, 131 indicated that they do not treat food-producing animals, and do not consult with/provide advice to veterinarians who treat food-producing animals. This indicates that the information provided by veterinarians to the CVO as part of the annual renewal and registration process may reflect their historic interests and not their current practices. Due to their lack of involvement with food-producing animals, these respondents did not complete the remainder of the survey and are not included in further analysis. Therefore, the total number of responses analyzed was 335 (466 minus 131) which is the number of respondents who indicated that they either treat food-producing animals or consult with/provide advice to veterinarians who treat food-producing animals. Of these 355 respondents, 63% treat food producing animals, 21% both treat and consult with or provide advice to veterinarians who treat food-producing animals, and 16% provide advice to, or consult with veterinarians who treat food-producing animals. Nine respondents did not answer this question but completed the survey so were deemed to be involved with food-producing animals. 8

9 Approximately 68% of respondents are involved with dairy cattle, 42% with beef cattle, 28% with sheep/goats, 12% with swine, 11% with poultry, and 6% with veal. It is noteworthy that the total percentage exceeds 100 since many veterinarians are involved with more than one species group. In fact, as shown in Figure 1, over 80% of the veterinarians involved with beef cattle, sheep/goats and veal calves spend only between 1 and 25% of their time dealing with these species. On the other hand, more veterinarians that deal with dairy cattle, poultry and swine work primarily on these species over 75% of time with over 50% of those involved with poultry and swine work exclusively on those species (Figure 2). The demographic characteristics for all survey respondents are presented in Table 1. It is difficult to draw conclusions from the demographic information due to the large amount of missing data. However, the largest percentage of respondents had between 2 and 4 veterinarians working in their practice, had one specific location for their practice, worked in south-western Ontario, and did not have additional qualifications. Respondents were fairly evenly spread across age categories, with the highest proportion (28%) being between 51 and 60. Similarly, year of graduation from veterinary school was fairly well distributed across categories, with the highest proportion (25%) graduating between 1981 and Lastly, of those that did report having additional qualifications (31%), the largest proportion (34%) reported having a graduate degree. When survey respondents were stratified by the species they reported working with, there was no significant difference between these veterinarians for any demographic characteristics. Results This section presents the results of the survey question by question. The reader may benefit from referring to the actual survey (See CVO GF2 Survey Instrument) for assistance in understanding this section. Source of antibiotics and frequency of use for important conditions and situations Important conditions and situations for each species group were identified and listed with respondents indicating the frequency of antibiotic treatment for each. The survey instrument explored sources of these antibiotics, differentiating those that were obtained from any source (i.e. provided through a veterinarian and/or obtained elsewhere without a prescription) versus those obtained elsewhere without a prescription. For some of the conditions, there was a significant difference between the two sources. However, for many conditions there was no significant difference. The results of these questions are presented by species in Tables 2 7. Beef cattle veterinarians indicated that therapeutic treatment of Bovine Respiratory Disease (BRD) in feedlot cattle, calf respiratory disease and calf navel ill are the conditions most frequently treated with antibiotics. The source of antibiotics differed significantly for therapeutic treatment of BRD in feedlot cattle, calf respiratory disease, calf diarrhea, and retained placenta metritis with more antibiotics coming from any source, as opposed to elsewhere without a prescription for these conditions/situations, suggesting that more of the antibiotics come from a veterinarian. For metaphylactic treatment of BRD in feedlot cattle, calf navel ill, lameness and pink eye there was no significant difference between the sources (Table 2). 9

10 Dairy cattle veterinarians indicated that post surgical administration after C-section, administration after Left Displaced Abomasum (LDA) and respiratory disease of calves are the conditions most frequently treated with antibiotics. The source of antibiotics differed significantly for all of these conditions/situations with more antibiotics coming from any source, as opposed to elsewhere without a prescription for these conditions/situations, suggesting that more of the antibiotics come from a veterinarian. For respiratory disease in calves, there was no significant difference between the sources (Table 3). Poultry veterinarians indicated that necrotic enteritis in broiler chickens, bacterial septicemia and air sacculitis (pneumonia) in chickens and turkeys are the conditions most frequently treated with antibiotics. The source of antibiotics differed significantly for yolk sacculitis in chickens and turkeys, as well as egg peritonitis in broiler breeder flocks with more antibiotics coming from any source, as opposed to elsewhere without a prescription for these conditions/situations, suggesting that more of the antibiotics come from a veterinarian. For bacterial septicaemia, osteomyelitis/tenosynovitis, spondylitis in chickens and turkeys, air sacculitis (pneumonia) in chickens and turkeys, enteritis in chickens and turkeys, necrotic enteritis in broiler chickens, and egg peritonitis in layer flocks, there was no significant difference between the sources (Table 4). Sheep and goat veterinarians indicated that treatment of respiratory disease in lambs and kids, treatment of clinical mastitis, enteritis in lambs and kids and treatment of respiratory disease in lambs and kids are the conditions most frequently treated with antibiotics. The source of antibiotics differed significantly for post-parturient fever, anorexia and depression, with more antibiotics coming from any source, as opposed to elsewhere without a prescription for this conditions/situation, suggesting that more of the antibiotics come from a veterinarian. The source of antibiotics differed significantly for prophylaxis of respiratory disease, with more antibiotics coming from elsewhere without a prescription as opposed to any source, for this conditions/situation, suggesting that more of the antibiotics come from elsewhere. The significant difference between sources for treatment or prophylaxis of foot disease cannot be interpreted. For enteritis in lambs and kids, treatment of respiratory disease in lambs and kids, treatment or prophylaxis of abortion, treatment of clinical mastitis and prophylaxis of mastitis, there was no significant difference between the sources (Table 5). veterinarians indicated that E. coli in nursing piglets, Streptococcus suis in the nursery barn, Glasser s disease in the nursery barn, and Actinobacillus plueropneumoniae in the grower/finisher barn are the conditions most frequently treated with antibiotics. The source of antibiotics differed significantly for E. coli in nursing piglets, Streptococcus suis in the nursery barn, Actinobacillus plueropneumoniae in the grower/finisher barn, and Metritis/Mastitis/Agalactia in sows with more antibiotics coming from any source, as opposed to elsewhere without a prescription for these conditions/situations, suggesting that more of the antibiotics come from a veterinarian. The significant difference between sources for Mycoplasma respiratory disease in the grower/finisher barn cannot be interpreted. For Glasser s disease in the nursery barn, Mycoplasma respiratory disease in the nursery barn, Lawsonia ileitis in the grower/finisher barn, and lameness in sows, there was no significant difference between the sources (Table 6). veterinarians indicated that treatment of calf respiratory disease is the condition most frequently treated with antibiotics. Since only 14 veterinarians responded as being involved with 10

11 veal calves, statistical comparisons cannot provide an understanding of the differences between these conditions/situations. However, the majority of respondents reported that producers obtained antibiotics from any source (provided through a veterinarian or obtained elsewhere) more frequently than elsewhere without a prescription for all of these conditions which might suggest that more antibiotics come from a veterinarian. Factors influencing decision to use antibiotics Respondents rated a series of factors as to their importance in deciding whether or not to use antibiotics. The history and clinical picture of the individual animal was the most important factor influencing their decision on whether to recommend antibiotics, with approximately 85% rating it as very important. History and clinical presentation of the herd and withholding/withdrawal time were rated as the next most important factors, with approximately 63% and 45% of respondents rating them as very important respectively (Table 8). When respondent ratings are compared across species, some significant differences were noted. Specifically, the history and clinical picture of the animal was less important for swine and veal veterinarians. In addition, owner preference and demands were of little importance for sheep/goats and poultry veterinarians, while withholding/withdrawal time was very important for dairy veterinarians (Figure 3). Beef, dairy, poultry, sheep and goat, and veal respondents all rated the level of importance of the history and clinical picture of the animal similarly, with the majority of respondents rating it as very important. However, swine respondents were split as to whether this factor was very important or important (Figure 4). Beef, dairy, swine and veal respondents similarly rated owner preferences and demands as important factors in influencing their decisions. However, poultry and sheep/goat respondents reported that this was of little importance in influencing their decisions (Figure 5). Nearly 70% of dairy respondents rated withholding/withdrawal time as very important. While respondents in other commodity groups also rated this as highly influential, the majority rated withholding/withdrawal time as important (Figure 6). As shown in Table 8, when the factors within each species group are compared, the responses among each species group are significantly different. The history and clinical picture of the individual animal, followed by the history and clinical presentation of the herd, are significantly more important, for all species groups, than the other factors. Among dairy respondents, withholding/withdrawal time is also significantly more important than the remaining factors influencing antibiotic use on the farm. Among beef and sheep/goat respondents, older respondents were significantly more likely than younger respondents to rate the potential for resistance as important or very important when considering whether or not to recommend antibiotics. Similarly, respondents dealing with sheep/goats followed this trend, with a significantly higher proportion of older respondents rating the potential for resistance as important or very important when considering whether or not to recommend antibiotics, compared to younger respondents. No other significant associations 11

12 between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. Factors influencing choice of antibiotic Respondents rated a series of factors as to their importance in deciding which antibiotic to use. Respondents rated the history and clinical presentation of the herd as the most important factor influencing their decision choice of which antibiotic to use, with approximately 63% of respondents rating it as very important. History and clinical picture of the individual animal and withholding time were rated as the next most important, with approximately 53% and 48% of respondents rating them as very important, respectively (Table 9). When respondent ratings are separated by the various species they work with, the cost of antibiotics, appropriate species and indication label, route of administration, withholding time, and culture and sensitivity results were significantly different when considering which antibiotic to use in a specific situation between veterinarians working with different species (Figure 7). The majority of swine, veal, beef and dairy respondents rated cost as important in their decision to choose a specific antibiotic. However, a large proportion of poultry respondents (42%) rated cost as of little importance, with another 15% of respondents rating it as not important (Figure 8). Yet, relatively small proportions of the overall respondents felt that the cost of antibiotics was very important in their decision-making process (Table 9). The majority of veal, poultry, swine, dairy and beef respondents rated appropriate species and indication on label as either very important or important. However, respondents who deal with sheep/goats were more divided, with approximately 37% rating appropriate species and indication on label as of little importance, and an additional 14% rating it as not important (Figure 9). Route of administration was most important for poultry respondents, where nearly 60% of respondents rated it as a very important. For a beef, dairy, sheep/goat and swine respondent, route of administration was generally important. respondents were evenly distributed with respect to this factor, with one third rating route of administration as very important, another third rating it as important, and the final third rating it as of little importance (Figure 10). Withholding time was very important for the majority of poultry, dairy, and swine respondents. and beef respondents were split between rating as very important or important, but the majority of respondents clearly view this as important at the very least. Respondents who deal with sheep/goats were more divided. While the majority rated withholding time as important, nearly 20% felt this factor was of little importance (Figure 11). While the majority of veal respondents rated culture and sensitivity results as very important, the other species groups had different ratings. The largest proportion of poultry, swine, dairy and sheep/goat respondents rated this as important, while the majority of beef respondents rated this as of little importance (Figure 12). When the factors within each species group are compared, the responses among each species group are significantly different. The history and clinical picture of the individual animal, followed by the history and clinical presentation of the herd, were significantly more important, for all 12

13 species groups, than the other factors influencing which specific antibiotic to use in a given situation. For dairy, poultry, swine and veal respondents, withholding time was also significantly more important than the remaining factors. In addition, for poultry respondents, the route of administration was also significantly more important than the remaining factors (Table 9). Among respondents who deal with sheep/goats, having the appropriate species and indication on the label was significantly more important for respondents that exclusively dealt with sheep/goats compared to veterinarians who also dealt with other species. No other significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. Frequency of use of antibiotics in an extra-label manner Respondents provided information on the frequency with which they use antibiotics in an extralabel manner. While 85% of respondents reported using antibiotics in an extra-label manner at some level, the largest proportion of respondents (36%) reported using antibiotics in an extra-label manner rarely, which was significantly higher than the other categories. A total of 21% of respondents use antibiotics in an extra-label manner often using them often in this capacity and only 15% of respondents reported never using antibiotics in an extra label manner (Table 10 and Figure 13). When separated by species, sheep/goat respondents most frequently used antibiotics in an extralabel manner, followed by swine, poultry, veal, dairy and beef respondents (Table 10). No significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. Reasons for use of antibiotics in an extra-label manner Respondents rated a series of reasons for extra-label antibiotic use. Ratings for the various reasons were often mixed, with respondents well represented in each of the four categories. The main reasons contributing to often use antibiotics in an extra-label manner were indication differs from label (28%), followed by species differs from label (22%). The main reasons contributing to occasionally using antibiotics in an extra-label manner were duration of treatment differs form label (51%), indication differs from label (50%), and dosage differs from label (45%) (Table 11 and Figure 14). When respondent ratings are separated by the various species they work with, species differing from the label, dosage differing from the label, duration of treatment differing from the label, and culture and sensitivity results were significantly different between veterinarians involved with the different species (Table 11). Over 80% of respondents who deal with sheep/goats responded that they often used antibiotics in an extra-label manner due to species differing from label. The largest proportion of poultry and swine respondents responded that they occasionally used antibiotics in an extra-label manner for this reason. It is noteworthy that over 20% of beef and dairy respondents reported never using antibiotics in an extra-label manner due to species differing from label (Figure 15). The largest proportion of each species group responded that they occasionally use antibiotics in an extra-label manner due to the dosage differing from the label. The second largest proportion of 13

14 poultry, sheep/goat, and swine respondents responded that they often used antibiotics in an extra-label manner for this reason, while the second largest proportion of beef, dairy and veal respondents reported that they rarely used antibiotics in an extra-label manner as a result of the dosage differing from the label (Figure 16). Over 60% of sheep/goat respondents said they never use antibiotics in an extra-label manner due to the duration of treatment differing from the label. The largest proportion of respondents among the other species groups responded that they occasionally used antibiotics in this way as a result of the duration of treatment differing from the label (Figure 17). The majority of poultry, swine and veal respondents reported that they occasionally used antibiotics in an extra-label manner due to culture and sensitivity results. However, the largest proportion of respondents who deal with beef, dairy, and sheep/goats responded that they rarely use antibiotics in this way due to culture and sensitivity results (Figure 18). When the factors within each species group are compared, the responses among each group are significantly different, except among veal respondents. For beef and dairy respondents, the most important reasons for using antibiotics in an extra-label manner were dosage, indication differing from label, and duration of treatment differing from the label. For sheep/goat and swine respondents, dosage, indication differing from label, duration of treatment differing from the label and species differing from the label significantly influenced extra-label antibiotic. In addition to these factors, route of administration also significantly influenced poultry respondents to use antibiotics in an extra-label manner (Table 11). Among beef respondents, younger veterinarians were significantly more likely than older individuals to report more frequent extra-label antibiotic use as a result of the route of administration differing from the label. No other significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. Control over antibiotic use on farm Respondents were asked if they felt they had control over the use of antibiotics on the farms that they serve. Approximately 52% of respondents responded that they often had control over antibiotic use on the farms that they serve, and this proportion was significantly higher than always, occasionally, rarely or never. However, over 30% reported feeling occasionally in control, and nearly 10% reporting that they rarely have control (Table 12 and Figure 19). When respondent ratings are separated by the various species with which they work, the frequency with which respondents feel they have control over antibiotic use on the farms that they serve was significantly different (Table 12). The largest proportion of swine, veal, dairy, beef and poultry respondents indicated that they often feel in control over antibiotic use. However, more than 20% of respondents in each of these species groups rated only occasionally feeling in control over antibiotic use. No significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. 14

15 Written Protocols A series of three questions was designed to probe the influence and role of veterinarians regarding written protocols for use of antibiotics on farms. Role in establishing written protocols for antibiotic use Respondents provided information on the frequency with which they felt they had a role in establishing written protocols for the use of antibiotics on farms that they serve. The largest proportion of respondents (43%) reported that they often have a role in establishing written protocols for use of antibiotics on the farms that they serve, and this proportion was significantly higher than other categories. However, responses were largely mixed, with 20% reporting that they always have a role, while another 21% reporting they only occasionally have a role in establishing written protocols (Table 13 and Figure 21). When respondent ratings are separated by the various species they work with, the frequency with which respondents feel they have a role in establishing written protocols for use of antibiotics on the farms they serve was significantly different (Table 13). The largest proportion of dairy, swine, and beef respondents felt that they often have a role in establishing written protocols. Small ruminant respondents were more diverse, with many rating that they occasionally (29%), or rarely (25%), have a role. Poultry respondents were similarly diverse, with nearly one third rating that they always have a role and one third rating that they occasionally have a role (Figure 22). No significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. Role in implementing written protocols for antibiotic use Respondents provided information on the frequency with which they felt they had a role in implementing written protocols for the use of antibiotics on farms that they serve. The largest proportion of respondents (39%) reported that they often have a role in implementing written protocols for use of antibiotics on the farms that they serve, and this proportion was significantly higher than other categories. However, responses were largely mixed, with another 26% reporting that they only occasionally have a role in implementing written protocols, while another 16% reported always having a role. Overall, roles among veterinarians appear to be very mixed (Table 14 and Figure 23). When respondent ratings are separated by the various species they work with, the frequency with which respondents feel they have a role in implementing written protocols for use of antibiotics on the farms they serve was significantly different (Table 14). Nearly 60% of swine respondents and 50% of dairy respondents indicated that they often have a role in implementing written protocols for antibiotic use on the farms that they serve. In contrast, the largest proportion of respondents among sheep/goats (39%), and poultry (33%) felt that they occasionally have a role. While the largest proportion of respondents among veal and beef respondents felt that they often have a role, the distributions were very similar, with many respondents in these species groups rating that they occasionally, or rarely, have a role in implementing written protocols (Figure 24). No significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. 15

16 Role in ensuring compliance with written protocols for antibiotic use Respondents provided information on the frequency with which they felt they had a role in ensuring compliance with written protocols for the use of antibiotics on farms that they serve. Responses were generally mixed, with the largest proportion of respondents (31%) reporting that they often have a role in ensuring compliance with written protocols for use of antibiotics on the farms that they serve. However, this proportion was not significantly higher than the other role categories (Table 15 and Figure 25). When respondent ratings are separated by the various species they work with, the frequency with which respondents feel they have a role in ensuring compliance with written protocols for use of antibiotics on the farms they serve was significantly different (Table 15). The majority of swine (56%) and veal (62%) respondents reported that they often have a role in ensuring compliance with written protocols. Ratings among the other species groups were more diverse. The largest proportion of beef respondents (34%) indicated that they occasionally have a role, while the largest proportion of dairy respondents (35%) indicated that they often play a role in ensuring compliance. Poultry respondents were very diverse, with a roughly equal proportion of respondents rating their role in each category available, except never. The largest proportion of sheep/goat respondents responded that they rarely have a role in ensuring compliance with written protocols (Figure 26). No significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. Trends in antibiotic use in last five years Respondents were asked if they have noticed any trends in the amount of antibiotics used on farms over the last 5 years. The majority of respondents (43%) reported not noticing a trend in the amount of antibiotics used on farms over the past 5 years, and this proportion was significantly higher than other categories. However, another 27% of respondents reported a slight decrease. In contrast, 19% of respondents reported a slight increase. In general, there appears to be a wide range of views with respect to the five-year trend in antibiotic use on farms (Table 16 and Figure 27). When respondent ratings are separated by the various species they work with, the trends in antibiotic use on farm over the past five years noticed by respondents were significantly different (Table 16). The largest proportion of sheep/goat (67%), beef (48%) and dairy respondents (39%) reported no trend noticed. However, over 20% of beef, sheep/goat, and veal respondents reported seeing a slight increase in antibiotic use. In contrast, over 30% of dairy, poultry and swine respondents reported seeing a slight decrease. Furthermore, 29% of poultry respondents and 22% of swine respondents reported a significant decrease in antibiotic use. Less than 13% of respondents in each species group reported seeing significant increases in the amount of antibiotics used on farms over the past five years (Figure 28). No significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. 16

17 Potential for reduction in antibiotic use if mandated Respondents were asked if they felt there is potential to reduce the amount of antibiotics used in practice in Ontario, if it was mandated. Approximately three quarters of respondents agreed that there is potential to reduce the amount of antibiotics used in practice in Ontario if it was mandated, and this proportion was significantly higher than those that disagreed (Figure 29). The majority of beef, dairy, swine and veal respondents agreed that there is opportunity to reduce the amount of antibiotics used in practice, and this difference was statistically significant from those that disagreed in their respective species groups. However, there was no agreement by respondents dealing with sheep/goats or poultry that there was an opportunity to reduce antibiotic use (Figure 30). No significant associations between these factors and respondents demographic characteristics (age, year graduated, number of species dealt with, additional qualifications) were found. Opportunity for reducing antibiotic use Respondents were provided with a list of conditions or situations and asked to rate where they felt there was the most potential for reduction in the amount of antibiotic used. Among beef respondents, metaphylactic treatment was identified as the most important situation where antibiotic use could be reduced. Dairy respondents felt that selective/targeted treatment was the most important opportunity to reduce use. Poultry, sheep/goat and swine respondents all felt it was most important to create a system where antibiotics are only available with a veterinarian prescription. Lastly, veal respondents felt the most important opportunity to reduce antibiotic use was to improve management and housing, and focus on prevention, rather than treatment (Table 17). Most commonly used antibiotics Respondents were asked to list the three most commonly used antibiotics in their practice. Table 18 presents the individual responses using the trade names, active ingredients or other identifiers that were provided by the respondents in a free flow text box. The use of penicillin was most popular among beef, dairy, poultry, sheep/goat and swine respondents. respondents reported the use of tetracyclines and draxxin most frequently. However, many of the antibiotics listed were identified in several different ways. As an example, ceftiofur products were listed as Excenel, Excede, Spectramast and Ceftiofur. As such, Table 19 presents the same information, with products containing the same active ingredients grouped. As well, each product group was categorized according to the Health Canada Categorization of Antimicrobials based on Importance in Human Medicine. In beef practice, the most commonly used antibiotics are in the tetracycline group (Category III), followed by flurofenicol group (Category II) then the penicillin group (Category II). In dairy practice, the most commonly used antibiotics are in the penicillin group (Category II), followed by ceftiofur products (Category I) then trimethoprim products (Category III). Poultry veterinarians reported using the penicillin group (Category II) most commonly followed by the tetracyclines (Category III) and Bacitracin (Category III). Approximately equal frequency of use by sheep/goat veterinarians was reported for the penicillin group (Category II), tetracyclines (Category III) and trimethoprim products (Category III). veterinarians selected the penicillin group (Category II) and tetracycline products (Category 17