305 1 Umbria Regional Centre of Veterinary Pharmacovigilance, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche, Via G. Salvemini 1, 06126 Perugia, Italy. 2 Igiene degli allevamenti e produzioni zootecniche, Usl Umbria 1, Perugia, Italy. 3 Igiene degli allevamenti e produzioni zootecniche, Usl Umbria 2, Terni, Italy. 4 Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche Via G. Salvemini 1, 06126 Perugia, Italy. * Corresponding author at: Umbria Regional Centre of Veterinary Pharmacovigilance, Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche, Via G. Salvemini 1, 06126 Perugia, Italy. e-mail: f.scoppetta@izsum.it. Parole chiave Antimicrobici veterinari, Farmaco-epidemiologia veterinaria Monitoraggio, One Health, Restistenza antimicrobica, Sanità pubblica veterinaria. Riassunto La diffusione della resistenza antimicrobica e la presenza di residui nei prodotti di origine animale destinati al consumo umano possono essere conseguenze dell'uso degli antimicrobici in veterinaria. I dati sul consumo sono quindi molto richiesti. Gli obiettivi di questo studio sono di stimare una dose definita giornaliera regionale (DDDvet_Umbria) per tutti gli antimicrobici prescritti in Umbria nel 2014 e di analizzare le prescrizioni per bovini, suini, piccoli ruminanti, pollame, trote arcobaleno e cavalli destinati alla produzione alimentare. Le specie più trattate sono state nel 2014 i suini, il pollame e il pesce (le trote), per i quali sono stati utilizzati prevalentemente beta-lattamici. Gli antimicrobici di importanza critica sono stati prescritti oltre che per suini e pollame, anche per i bovini; la colistina è risultato essere l’antimicrobico più frequentemente usato nei suini e nel pollame. Superando i limiti di altri approcci proposti, questo studio indirizza la comprensione del consumo di antimicrobici negli animali da produzione alimentare. I dati sono utili per quantificare il consumo antimicrobico, identificare le fattorie problematiche e sostenere un confronto tra diverse specie animali. Valutazione farmaco-epidemiologica di prescrizioni antimicrobiche nell’Italia centrale, Umbria 2014 Keywords Veterinary antimicrobials, Antimicrobial monitoring, One Health, Antibiotic resistance, Veterinary pharmaco-epidemiology. Summary Veterinary antimicrobial use could lead to problems such as the spread of antimicrobial resistance or the presence of residues in animal-derived products for human consumption. Related to this, data on drug consumption is in strong demand. The aims of this study are therefore to evaluate a regional Defined Daily Dose (DDDvet_Umbria) for all of the antimicrobials prescribed in Umbria during 2014 and to analyse prescriptions for cattle, swine, small ruminants, poultry, rainbow trout, and food-producing horses. Consumption, prevalence, and intensity of use indicators are calculated. Swine, poultry, and fish were the most treated species during 2014. Beta-lactams were the most frequently consumed antimicrobials for these species. Critically important antimicrobials were mostly prescribed for swine, poultry, and cattle. Colistin was the most frequently used critically important antimicrobial to treat swine and poultry. This study helps to better understand antimicrobial consumption in food-producing animals by overcoming the limitations of other proposed approaches. Our data are useful for quantifying antimicrobial consumption, identifying problematic farms, and supports a comparison among different animal species. Results highlight that the critical sectors in drug consumption – where the highest use of antibiotics were found – are swine, poultry, and trout farms. Fausto Scoppetta1*, Massimo Chiovoloni2, Guglielmo Spernanzoni3, Giovanni Filippini4 and Marinella Capuccella1 Pharmaco-epidemiological evaluation of veterinary antimicrobial prescriptions for cattle, swine, small ruminants, poultry, rainbow trout, and food-producing horses in Umbria in 2014 Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 Accepted: 16.07.2017 | Available on line: 31.12.2018 306 Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 animal species, and human (EMA 2015, EMA/ESVAC 2016). Defined daily doses (DDDvet) for each active ingredient per animal species and administration route are set as a reference parameter for evaluating veterinary active ingredients consumption and their comparisons across animal species and farming systems (EMA 2015, Postma et  al. 2015, WHO 2013, EMA/ESVAC 2016). This information provides a valuable basis for decisions relating to the reduction of misuse of veterinary drugs, especially antibiotics, and may therefore be of interest to relevant Health Authorities. However, the list of DDDvet provided by the EMA/ESVAC for antimicrobials is reserved for swine, broilers, and cattle; and there is limited information about the registration and use of the veterinary drug handbooks in different member states, including Italy (EMA/ESVAC 2016). Nevertheless, this is an important step towards a standardised approach in quantifying antibiotics in Europe. The extension of the list to include other animal species and all active ingredients in veterinary medicine, through the use of information gathered from all the European countries, could improve our knowledge of drug utilisation in veterinary medicine. The aim of this study is to begin addressing some of these gaps by providing data on antimicrobial consumption in cattle, swine, small ruminants, poultry, rainbow trout, and food-producing horses in Umbria, according to the methods proposed by the EMA/ESVAC (2016). Data are provided by the veterinary prescriptions received by the Umbrian public health authorities in 2014. Materials and methods General analysis Information about the total number of farms and livestock animals per species present in Umbria during 2014 was obtained from a national database, which is available at www.vetinfo.sanita.it (BDN) (Table I). The BDN does not include information on antibiotic prescriptions in veterinary medicine. Data on antibiotic prescriptions were obtained from the hard copies of veterinary drug prescriptions stored by the veterinary public authorities responsible for veterinary drug control; these authorities receive veterinary prescription copies from drug vendors, a mandatory procedure under both European and national Italian law. Copies of veterinary drug prescriptions were collected on a monthly basis and transferred to Microsoft Excel and Microsoft Access. Prescriptions were split by species. The prescriptions admitted in this study were those for cattle, swine, small ruminants, poultry (defined according to council directive 2005/94/EC), rabbits, rainbow trout (fish), and food-producing horses. Damaged prescriptions, off-label antibiotic drugs registered for humans, Introduction Veterinary antimicrobials are some of the veterinary drugs used as tools to prevent, control, and treat infections. They also protect animal welfare and health, and improve growth and production. Antibiotics must be used responsibly in order to guarantee public health by reducing the spread of antimicrobial resistance and the risk of residues in animal derived food products. (Economou and Gousia 2015). It is well known that any antibiotic administration both in animals and in humans could lead to the selection of resistant bacteria (Silbergeld et  al. 2008); this has become an increasing problem worldwide for both veterinary and human medicine (Wassenaar 2005). The European Union is working towards the spread of antimicrobial resistance reduction by promoting regulations and guidelines. In 2006, the use of antibiotics for growth promotion was banned (European Commission 2003). Recently, a statement regarding the guidelines on the prudent use of antimicrobials in veterinary medicine was issued by the European Commission; it identified the need to monitor plans for various types of resistance in each production chain, as well as for pathogens, zoonotic and commensal bacteria, and for antibiotic consumption (European Commission 2015). Knowledge of both aspects is fundamental in assessing the relationship between resistance and the use of antimicrobials (van Rennings et  al. 2015). The Directive 2003/99/EC makes it mandatory to monitor antimicrobial resistance in zoonotic bacteria; furthermore, European or national plans have been implemented for commensal and pathogen germs (Ministry of Health 2012, EFSA 2016). To date, no obligation regarding coordinated data-collection in Europe (van Rennings et  al. 2015) has been defined, although some countries have recently developed their own strategies (van Rennings et al. 2015, AURES 2013, SVARM 2012, Merle et  al. 2014, DANMAP 2014, MARAN 2015). Since 2010, the European Medicines Agency launched the ESVAC (European Surveillance of Veterinary Antimicrobial Consumption) project, which focuses on antibiotics. Specifically, the ESVAC initiative relates to ‘collecting and developing a coordinated approach for the collection and reporting of data on the use of antimicrobial agents in animals from the European Union and European Economic Area Member States’ (EMA/ESVAC 2015). The EMA/ESVAC group has provided a guideline on the standardisation of data collection and evaluation of veterinary drug consumption (EMA 2015) to overcome limits shown by other proposed units of measurements (Merle et  al. 2014, EMA/ESVAC 2016). This guideline proposes ‘standardised fixed units of measurement for the reporting of data on consumption by species that take into account differences in dosing’ in order to compare consumption data between countries, Veterinary antimicrobial prescriptions in Umbria Scoppetta et al. 307Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 • Intra-mammary administration for treatment during lactation (cattle and small ruminants): the number of tubes per teat daily administered. • Intra-mammary administration for dry therapy (cattle and small ruminants): the number of tubes per udder daily administered. • Intrauterine administration: mg a.i./animal. DDDvet_Umbria was calculated for each a.i. as the average value of recommended dosage reported in the various leaflets about each prescribed drug. For those a.is. for which European Medecines Agency (EMA) has provided, DDDvet values for oral and parenteral administration for cattle, swine, and broilers, a ratio between DDDvet_Umbria and DDDvet was calculated. Prescribed DDDs were evaluated by dividing the total amount of each a.i. in mg by DDDvet_Umbria of this a.i. Consumption analysis The following indicators of antibiotic consumption were evaluated: • Defined daily doses (DDD) per 1,000 animals per day: the mean number of doses consumed every day by 1000 animals (DDDs/1,000 animals-die). • DDDs per 1000 farms per day: the mean number of doses consumed every day by 1,000 farms (DDDs/1,000 farms-die). • Prevalence of use: the number of drug users (farms) divided by the overall farms present in the Umbria region in 2014 (%). • Intensity of use: the number of prescribed DDDs divided by the number of farms with at least 1 antibiotic prescription in 2014 (DDDs/ farms). Analysis was performed for each productive sector. For food-producing horses and rabbits, no information was available in BDN regarding the number of animals and number of farms, while for rainbow trouts (fish), the only available information was related to farms. Therefore, for food-producing horses and rabbits, only prescribed DDDs were evaluated, while for rainbow trout (fish) only DDDs/1,000 farms-die. Results General consumption analysis The total number of prescriptions that were analysed was 10,051, which corresponded to 23,146 antibiotic records. Partial or incomplete records accounted and antibiotic drugs with topical administration for which it was impossible to evaluate a DDDvet_ Umbria standard, were excluded from the study. For each prescription, the following information was transferred to the database: commercial name, posology, number and productive category of treated animals, days of treatment, and withdrawal periods. The active ingredient (a.i.) contained in each prescribed drug was considered a single record. Analysis was performed taking into consideration each class of antibiotic and the sub-group ‘Critically Importance Antimicrobials’ (CIAs), according to the World Health Organization (WHO 2011). DDDvet_Umbria determination and prescribed DDDs evaluation DDDvet_Umbria values were calculated according to the EMA indication (EMA 2015) for each a.i., and differentiated by animal species. Different DDDvet_Umbria values were evaluated for each administration route and for those a.is. prescribed in synergistic combination with other a.is. This means that each a.i. could have 2 or more different DDDvet_ Umbria values according to different animal species usage, with a different administration route, and/or in a synergistic combination with other a.i. utilisation. A database with all the prescribed drugs in 2014 in Umbria was created by collecting information about the recommended dose according to each respective leaflet (including premixes for medicated feed) available from the Ministry of Health veterinary drug manual1. Each prescription drug entry was expressed differently for each administration route, in-line with (EMA/ESVAC 2016): • Parenteral and oral route of administration: mg a.i. /kg body weight. Scoppetta et al. Veterinary antimicrobial prescriptions in Umbria 1 https://www.vetinfo.sanita.it/j6_prontuario/public/. Table I. Number of farmed animals and farms in Umbria in 2014. Umbria Region Cattle Farmed animals 56,694 Farms 3,088 Swine Farmed animals 212,105 Farms 3,361 Small ruminants Farmed animals 132,437 Farms 3,510 Poultry Farmed animals 7,774,832 Farms 261 Fishes (trouts) Farmed animals - Farms 15 Total Farmed animals 8,176,068 Farms 10,235 308 Veterinary antimicrobial prescriptions in Umbria Scoppetta et al. Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 was for oral administration (44.21%), followed by parenteral (40%), intra-mammary (12.63%), and intrauterine (3.16%). A comparison between DDDvet_Umbria and DDDvet provided by EMA was performed for 118  a.is. (22 for broilers, 54 for swine, and 42 for cattle). The average value of DDDvet_Umbria/DDDvet was 1.05 (0.65 for cattle, 1.007 for poultry and 1.55 for swine). Swine were the most treated animal species in Umbria in 2014 (11,930.02  x  105 prescribed DDDs), followed by poultry (2,853.64  x  105 prescribed DDDs), cattle (275.11  x  105 prescribed DDDs), rabbits (188.90 x 105 prescribed DDDs), aquaculture (188.28  x  105 prescribed DDDs), small ruminants (24.26  x  105 prescribed DDDs), and food-producing horses (1.48 x 105 prescribed DDDs) (Figure 1). The results on antimicrobial consumption using for 2.47% of the total and off-label records accounted for 10.61% of the total. The number of antimicrobial records was 14,249, of which 3339 were for CIAs. Poultry – especially game – showed the highest number of off-label records (58.35%), followed by rabbits (10.57%), swine and small ruminants (9.94%), rainbow trout (4.02%), food-producing horses (3.59%), and cattle (3.59%). The majority of prescriptions were mostly for swine (37.11%) and cattle (24.45%), followed by rabbits (17.48%), poultry (13.03%), small ruminants (6.85%), food-producing horses (0.60%), and rainbow trout (0.49%). Regarding rabbits, 98.08% of evaluated prescriptions were for animals bred for home consumption. Antimicrobials were the most prescribed type of drugs in 2014 (100% of prescribed records in rainbow trout, 66% in cattle, 63.72% in swine, 57.37% in rabbits, 50% in poultry, 47.17% in small ruminants, and 44.50% in food-producing horses). A total of 285 DDDvet_Umbria values were evaluated in this study. Values referred to 65 a.is. classified in 16 antimicrobial classes2 and differentiated by animal species, administration route, and synergistic combinations. The list of a.is. classified by classes of drugs is shown in Table II. Cattle (33.33%), swine (23.16%), and poultry (20.70%) showed the highest number of evaluated DDDvet_Umbria values; followed by rabbits (9.47%), small ruminants (8.42%), food-producing horses (3.16%), and fish (1.75%). The largest number of evaluated DDDvet_Umbria values 2 Lists of DDDvet_Umbria values are available from the authors. Table II. Classification of antimicrobials prescribed in 2014 in Umbria. Classes Active ingredients Aminoglycosides Apramycin, amikacin, dihydrostreptomycin, streptomycin, gentamicin, kanamycin, framycetin, nemoycin, spectinomycin, paromomycin Amphenicols Thiamphenicol, florfenicol Cephalosporins, First Generation Cefacetrile, cefopirin, cefazolin, cefalonium, cefalexin Cephalosporins, Third Generation* Cefoperazone, ceftiofur Cephalosporins, Fourth Generation* Cefquinome Ionophore antimicrobials Monensin Lincosamides Lincomycin Macrolides* Erithromycin, spiramicin, tilmicosin, tylvalosin, tulathromycin, tylosin, tildipirosin, gamithromycin Nitrofurans Furaltadone Penicillin Amoxicillin, amoxicillin + enzime inhibitor,penethamate hydriodide, phenoxymethylpenicillin, cloxacillin, dicloxacillin, benzylpenicillin, procaine penzylpenicillin, benethamine penicillin, ampicillin Pleuromutilin Tiamulin, valnemulin Polymyxins and Polipeptidic antimicrobials* Colistin, bacitracin Quinolones/Fluoroquinolones* Enrofloxacin, flumequine, oxolinc acid, danofloxacin, marbofloxacin Rifaximins Rifaximin Sulfonamides and Trimethoprim Sulfadiazine, sulfadimidine, sulfadimethoxine, sulfamethoxazole, sulfamonomethoxine, phthalylsulfathiazole, sulfathiazole, sulfamethoxypyridazine, sulfamerazine, sulfaguanidine, trimethoprim Tetracyclines Oxytetracycline, chlortetracycline, doxycycline * Critically important antimicrobials. Figure 1. Antimicrobials: prescribed Defined daily doses (% per animal species). 309 Scoppetta et al. Veterinary antimicrobial prescriptions in Umbria Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 Quinolones/fluoroquinolones and polymixins showed a moderate utilisation for cattle. A different type of behaviour could be observed in the consumption of CIAs per farm (Figure 2b). In this case, poultry showed the highest consumption of CIAs, particularly colistin, which is extensively prescribed for swine farms as well. Macrolides and quinolones/fluoroquinolones were also widely prescribed for poultry; a high use of macrolides was also indicated for swine. For both, animals and farms, the lowest use of CIAs was found in small ruminants and for these species, colistin was the most widely prescribed CIAs. Figure 3 shows prevalence (%) and intensity of use in reference to CIAs. Poultry showed the highest farm prevalence, especially for macrolides, quinolones/fluoroquinolones, and polymixins. Polymixins (essentially colistin) showed the highest intensity of use on farms, particularly on swine and poultry farms, followed by macrolides in swine, and quinolones/fluoroquinolones in poultry. Antimicrobial consumption per animal species Data on antibiotic consumption analysis per animal species are shown in Table III, Table IV, and Table V. DDDs/1,000 animals-die confirms swine as the most treated farm animal in 2014 (15.41 x 103 DDDs/1,000 animals-die), followed by cattle, poultry, and small ruminants (1.33  x  103; 0.10  x  103; 0.05  x  103 DDDs/1,000 animals-die, respectively). Poultry and fish farms instead showed a high consumption of antimicrobials (fish: 3,329.35  x  103; poultry: 2,995.47 x 103; swine: 972.48 x 103; cattle: 24.41 x 103; small ruminants: 1.89 x 103 DDDs/1,000 farms-die). Data showing consumption, prevalence, and intensity of use for each animal species are found in Tables III, IV, and V. CIAs were prescribed mostly for swine, poultry, and cattle (Table III, Table IV, Figure 2, and Figure 3). In prescribed DDDs, the highest percentage of CIAs was for swine (72.23%), followed by poultry (25.18%), cattle (1.82%), rabbits (0.73%), small ruminants (0.02%), rainbow trout (0.02%), and food-producing horses (0.001%). A large number of prescriptions for polymixins (essentially colistin) and macrolides was found in swine, which relates to the number of farmed animals (Figure 2a). Macrolides were also prescribed for cattle. However, in this species, third-generation cephalosporines was the most used class of CIAs. Table III. Consumption of veterinary antimicrobials in Umbria in 2014 in food-producing animals. Cattle Swine Poultry Small Ruminants Fishes (trout) Class DDDs/1000 animals‑die DDDs/1000 farms‑die (x 102) DDDs/1000 animals‑die DDDs/1000 farms‑die (x 102) DDDs/1000 animals‑die DDDs/1000 farms‑die (x 102) DDDs/1000 animals‑die DDDs/1000 farms‑die (x 102) DDDs/1000 farms‑die (x 102) Aminoglycosides 148.36 27.24 290.87 183.56 0.26 76.26 6.12 2.31 0 Monensin 143.47 26.34 0 0 0 0 0 0 0 First generation cephalosporins* 0.11 0.02 0 0 0 0 0 0 0 Thrid generation cephalosporins* 201.23 36.94 19.58 12.36 0 0 0 0 0 Fourth generation cephalosporins* 15.77 2.90 4.76 3 0 0 0 0 0 Quinolones/ fluoroquinolones* 83.09 15.26 98.05 61.88 5.71 1,697.06 0.88 0.33 850 Amphenicols 14.90 2.74 559.26 352.93 0.04 11.64 0 0 13,014.55 Beta-lactamase inhibitors 2.98 0.55 45.33 28.60 0 0 0 0 0 Lincosamides 34.87 6.40 3122.88 1,970.78 0.03 7.44 0.02 0.01 0 Nitrofurans 0 0 0 0 0 0.91 0 0 0 Macrolides* 105.52 19.37 1,425.45 899.57 6.51 1,935.98 1.02 0.38 0 Penicillin 287.62 52.81 3,972.34 2,506.85 38.50 11,446.70 8.60 3.24 0 Pleuromutilins 0 0 340.77 215.05 0.10 29.06 0 0 0 Polymixins* 42.42 7.79 3,205.10 2,022.66 32.98 9,805.99 3.21 1.21 0 Rifaximin 0.07 0.01 0 0 0 0 2.61 0.98 0 Sulfonamides 99.20 18.21 994.92 627.87 5.13 1,525.68 0.60 0.23 71,355.70 Tetraciclines 94.14 17.28 1,330.51 839.66 7.47 2,222.55 26.93 10.16 26,181.82 Trimethoprim 55.72 10.23 792.27 499.98 4.09 1,216.35 0.21 0.08 70,880 * Critically important antimicrobials. 310 Veterinary antimicrobial prescriptions in Umbria Scoppetta et al. Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 compared to penicillin. A different kind of behaviour was discovered by evaluating the intensity of use, in that the highest value was shown by monensin, followed by third generation cephalosporins, tetracyclines, and macrolides. Penicillin, polymixins, lincosamides, and macrolides were the most prescribed classes of drugs for swine both at animal and farm level. Both prevalence and intensity of use were high in the same classes of drugs, particularly regarding the prevalence of penicillin, lincosamides, and macrolides. Aminoglycosides have shown a prevalence value higher than other classes of drugs despite a low consumption expressed for both DDDs/1,000 animals-die and DDDs/1,000 farms-die. Polymixins showed the highest value of DDDs/farms, followed by lincosamides and tetracyclines. Antibiotic consumption was principally related to penicillin and polymixins, both for single animals and single farms in poultry. Other classes of antimicrobials showed values of DDDs/1,000 animals-die and DDDs/1,000 farms-die far lower than penicillin and polymixins. Macrolides, penicillin, and quinolones/fluoroquinolones showed the highest values of prevalence. Penicillin and polymixins With regard to antibiotics used for cattle, beta-lactams, and particularly penicillin either alone or in combinations, were the most prescribed classes of drugs and showed a high prevalence. Aminoglycosides and quinolones/fluoroquinolones showed a higher prevalence than cephalosporines, despite its prevalence being generally lower when Table IV. Farm prevalence (%) and farm intensity of use [DDDs(Defined daily doses)/farms] of veterinary antimicrobials in Umbria in 2014 in food-producing animals. Cattle Swine Poultry Small Ruminants Fishes (trout) Class Prevalence (%) DDDs/ farms (x 103) Prevalence (%) DDDs/ farms (x 103) Prevalence (%) DDDs/ farms (x 103) Prevalence (%) DDDs/ farms (x 103) Prevalence (%) DDDs/ farms (x 103) Aminoglycosides 11.89 8.37 4.91 136.48 8.43 727.80 1.94 4.35 0 0 Monensin 0.45 212.07 0 0 0 0 0 0 0 0 First generation cephalosporins* 2.95 0.03 0 0 0 0 0 0 0 0 Thrid generation cephalosporins* 2.40 56.27 0.51 89.17 0 0 0 0 0 0 Fourth generation cephalosporins* 1.81 5.83 0.71 15.36 0 0 0 0 0 0 Quinolones/ fluoroquinolones* 6.06 9.20 3.69 61.22 29.89 16,196.96 0.74 1.63 26.67 21.25 Amphenicols 1.17 8.57 2.56 503.45 0.38 111.11 0.03 0.01 6.67 1,301.45 Beta-lactamase inhibitors 1.85 1.08 0.66 159.50 0 0 0.03 0.01 0 0 Lincosamides 2.79 8.39 4.55 1,580.18 2.68 71.00 0.03 1 0 0 Nitrofurans 3.24 21.84 4.02 817.45 39.46 18,477.26 0 0 0 0 Macrolides* 0 0 0 0 0.38 8.70 0.26 5.50 0 0 Penicillin 21.76 8.86 11.01 824.48 30.27 109,248.92 2.76 4.29 0 0 Pleuromutilins 0 0 2.26 347.13 1.53 277.34 0 0 0 0 Polymixins* 1.65 17.21 3.12 2,363.17 22.61 93,589.77 0.48 9.12 0 0 Rifaximin 2.33 0.02 0 0 0 0 0.06 63.08 0 0 Sulfonamides 5.31 12.52 3.66 626.22 21.84 14,561.28 0.23 3.62 20 2,378.52 Tetraciclines 2.9 22.65 3.60 851.29 26.05 21,212.30 3.13 11.83 33.33 523.64 Trimethoprim 2.72 13.73 2.59 705.01 19.16 11,609.02 0.03 10 33.33 1,417.60 * CIAs Table V. Prescribed DDDs (Defined daily doses) in Umbria in 2014 in horses and rabbits. Prescribed DDDs (x 103) Horses (food producing) Rabbits Aminoglycosides 41.11 279.51 Thrid generation cephalosporins* 3.82 0 Quinolones/fluoroquinolones* 2.00 366.00 Macrolides* 0 1,437.50 Penicillin 54.09 0 Pleuromutilins 0 3,795.57 Polymixins* 0 3,375.55 Sulfonamides 23.06 2,996.16 Tetracyclines 3.94 3,995.94 Trimethoprim 19.82 2,643.80 * Critically important antimicrobials. 311 Scoppetta et al. Veterinary antimicrobial prescriptions in Umbria Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 of antimicrobials in food-producing horses, while tetracyclines and pleuromutilins were mostly used in rabbits. Third-generation cephalosporines were prescribed only for food-producing horses and were mostly prescribed for rabbits (polymixins, quinolones/fluoroquinolones and macrolides), as were other classes of CIAs. Discussion The collection of veterinary drug use data and their descriptive analysis are important for public health (Collineau et al. 2016). Although the EMA have recently provided DDDvet values for antimicrobials for cattle, swine, and broiler, in this study we decided to use regional DDDvet_Umbria data for these species in order to facilitate a comparison between the animal species admitted in this study. Comparing the values for swine, cattle, and broilers assigned by us, to the values assigned by the EMA in 2016 (EMA/ESVAC 2016) demonstrates the strength of this study. The showed the highest values of intensity of use. The most prescribed classes of antibiotics in small ruminants were tetracyclines, penicillin, and aminoglycosides. Tetracyclines also showed the highest value of DDDs/farms as referred to antimicrobials. Tetracyclines and penicillin had the highest prevalence of use. Sulfonamides, either alone or in combination with trimethoprim, were the most prescribed class of drugs in rainbow trout; however, tetracyclines also showed a high value of prevalence, together with trimethoprim. Intensity of use was higher in sulfonamides, trimethoprim, and amphenicols. The last class of antibiotic was prescribed 100% off-labels. Quinolones/fluoroquinolones were the only CIAs prescribed in fish and showed the lowest values of consumption and intensity of use together with a high prevalence. Aminoglycosides, penicillin and potentiated sulphonamides were the most prescribed classes Figure 2. Focus on Critically important antimicrobials. a. DDDs (Defined daily doses)/1000 animals-die; b. DDDs/1000 farms-die. Figure 3. Focus on Critically important antimicrobials. a. Farm prevalence (%); b. Intensity of use [DDDs (Defined daily doses]/farms). 312 Veterinary antimicrobial prescriptions in Umbria Scoppetta et al. Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 most suitable unit of measurement to assess the relationship between antibiotic consumption and antibiotic resistance. This would be an appropriate follow-up study to the work presented here (Collineau et al. 2016). Beta-lactams, especially penicillin, were the most prescribed class of antimicrobials of all animal species monitored in 2014. This could be due to the lower cost of these drugs, short withdrawal periods (EFSA 2016, EMA/ESVAC 2015, De Briyne et al. 2014), and broad spectrum of activity, which is sometimes obtained through the association with clavulanic acid. The use of broad-spectrum antibiotics is another critical area relating to the spread of antibiotic resistance, especially when these are prescribed without any laboratory indications about bacterium sensibility (European Commission 2015). Swine and cattle were the animal species with the highest number of prescriptions in 2014. Together with small ruminants, these are the most bred species in Umbria; however, small ruminants are treated less than other livestock, probably for economic reasons and types of farming (Santman-Berends et al. 2014). The analysis of prescribed DDDs, DDDs/1,000 animals-die and DDDs/1,000 farms-die evaluated in 2014 in Umbria, confirmed the high use of veterinary drugs in swine but showed a lower drug use in cattle compared to poultry and fish, especially where drug consumption concerns farms. With cattle, the low antibiotic consumptions, expressed in prescribed DDDs, DDDs/1,000 animals-die, and DDDs/100 farms-die, could be explained by taking into account the fact that the units of measurement were influenced by the strength of each antimicrobial a.i. and in cattle, antibiotics with a high dosage were more often prescribed. Swine, poultry, and aquaculture represent 3 crucial livestock industries referred to drug consumption because of group treatments, high use of medicated feed (in swine and rainbow trout), and rapid growth of animals, especially for poultry and swine. These aspects could lead to an under- or over-estimation of live weight and consequently to mistakes in the drugs dosage calculation (Timmerman et  al. 2006, González et  al. 2010, Mancini et  al. 2010, Persoons et al. 2012, Zonca and Cagnardi 2012, Di Cesare et al. 2013, Trauffler et  al. 2014). This problem could also influence the occurrence of antimicrobial resistance (Catry et  al. 2003) in antibiotics in a positive sense. Our results confirm the high use of antimicrobials in swine and poultry and the potential influence that these livestock species can have on the spread of antibiotic resistance. Furthermore, swine and poultry showed a high consumption of CIAs, especially polymixins (colistin). Other studies highlight the use of colistin in pigs and poultry as the main class of CIAs for curing diarrhea, especially in piglets (De Briyne et  al. 2014, Callens et  al. 2012). Colistin differences could be attributed to the high number of registered products used by the EMA for DDDvet determination, which are based on the veterinary drug handbooks of nine countries, compared to our values, which are based on the registered products prescribed in only 1 Italian region. It is well-known that there are differences in suggested doses provided by leaflets of commercial products which depend, for instance, on the severity and place of infection or age of the considered animals (Timmerman et  al. 2006). The EMA’s decision to evaluate DDDvet using nine veterinary drug handbooks is an attempt to minimise the above-mentioned differences. This consideration is particularly important for cattle and swine, which have the highest number of registered products – about 3,000 for both species (https://www.vetinfo. sanita.it/j6_prontuario/public/), compared with other food-producing animals. Furthermore, there are not many veterinarians working in Umbria and, those who do work in the region often prescribe the same commercial products for different farms breeding the same animal species. There were few evaluated differences for poulty, which could be due to the lower number of registered products available for these animals – about 900 (https://www.vetinfo. sanita.it/j6_prontuario/public/). Nevertheless, the DDDvet_Umbria/DDDvet average value, which is 1.05, confirms the integrity of our approach. A comparison of the swine values was performed not only with the EMA values but also with the DDD values assessed recently in four European countries (Postma et al. 2015) and in Denmark by the project DANMAP (DANMAP 2014). Values for the oral administration of colistin and for the parenteral administration of ampicillin were assessed by Postma and colleagues (Postma et al. 2015) and were found to differ by only a few decimals from the same active ingredients assigned in our study. Off-label prescriptions were mostly made for game, fish, and food-producing horses, and revealed a lack of registered veterinary products. The availability of veterinary drugs as ‘registered products’ should be increased in order to avoid problems such as mistakes in dosage and in withdrawal periods, as well as to gain a better understanding about the safety and efficacy of prescribed drugs for all bred animals. The analysis of antibiotic consumption is often evaluated by considering animal body weight. However, in this study we chose to relate antibiotic consumption to the number of farms and bred animals in Umbria in 2014. This could facilitate an easier comparison with human medicine, where antibiotic consumption is expressed in DDDs/1,000 inhabitants-die, which is similar to our units of measurement (DDDs/1,000 animals-die and DDDs/1,000 farms-die) (Agenzia Italiana Farmaco 2016). Furthermore, Collineau and colleagues have recently indicated DDDs/1,000 animals-die as the 313 Scoppetta et al. Veterinary antimicrobial prescriptions in Umbria Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 should be used responsibly, in accordance with EMA recommendations (EMA 2013) in veterinary medicine. Furthermore, the EMA has recently provided information on the impact of colistin use in veterinary medicine on human medicine and antimicrobial resistance (EMA 2016). Data from this study could be useful to identify farms, veterinaries, and/or areas with a high consumption of CIAs, which in turn would be useful in guiding intervention efforts to encourage a more rational use of CIAs based on antibiogramme. Another important class of CIAs, mostly used in swine and poultry in other countries in 2014, was macrolides (Merle et  al. 2014, Trauffler et  al. 2014, van Rennings et al. 2015). This class of CIAs is usually used for the respiratory diseases and gastrointestinal diseases of swine (De Briyne et  al. 2014), which represent the main pathologies for this species. Even if macrolides were included in the CIAs listed by the WHO, because of the possibility of selecting macrolides-resistant Campylobacter spp. (WHO 2011), their use could be preferable to colistin, which is now one of the last resources in human medicine for the treatment of different kinds of infections caused by multidrug-resistant bacteria (EMA 2016). In the field of aquaculture in Italy, our results confirm the high use of antimicrobials. In farmed fish, antimicrobials were the only class of drug used in Umbria in 2014. This is in contrast with national and European policies, which tend to reduce antimicrobial use by increasing prevention practices such as vaccination (Ministero della Salute 2012, DANMAP 2014). One of the problems related to aquaculture is the small number of registered active ingredients; for example, neither anti-parasitic products nor florfenicol and erythromycin could be prescribed in Italy in 2014. Florfenicol and erythromycin can be prescribed only off-label, which is fundamental because they are elective drugs for some pathologies such as flavobacteriosis and lactococcosis (Zonca and Cagnardi 2012). However, it is necessary to consider that florfenicol was recently registered for farmed fish in order to guarantee animal health and production. In farmed fish, potentiated sulfonamides and tetracyclines were the most widely prescribed drugs in 2014 in Umbria. These were administered by medicated feed, with possible impacts on the spread of antibiotic resistance and environmental pollution (Zonca and Cagnardi 2012, Di Cesare et al. 2013, Lim et al. 2013). The same consideration could be made for quinolones/fluoroquinolones used in farmed fish in Umbria, since they are classified as CIAs. Third- and fourth-generation cephalosporins were prescribed mostly for cattle and were probably principally related to the treatment of mastitis and/or dry-cow therapy, as has already been stated in other countries (Lanza et  al. 2012, De Briyne et  al. 2014, Merle et  al. 2014). Cephalosporins are frequently used during dry periods to prevent mastitis and this practice continues to be considered important for reducing the spread of this invalidating pathology in dairy animals (Scoppetta et  al. 2016). Dry-cow therapies could impact the spread of antibiotic resistance, although literature on this association is limited (Rajala-Schultz et al. 2009). This could represent a serious public health concern, considering that third and fourth generation cephalosporins are among the few available possible therapies for serious Salmonella and E. coli infections in humans, especially children (WHO 2011). Lack of information concerning horses in BDN and problems related to non-computerisation of veterinary prescriptions limited our evaluation to prescribed DDDs only. Although prescribed DDDs in Umbria for 2014 for food-producing horses were lower with respect to other animal species, the lack of indicators for consumption in this area lead to a lack of available data for assessing horse treatment impact on the spread of antimicrobial resistance (Bowen and Clegg 2015, Weese 2015). The same considerations could be taken into account for rabbits, although, for this species, the most prescribed classes of antibiotics were tetracyclines and pleuromutilins, which are not considered CIAs. One of the biggest problems related to the quantification of drug use is linked to the differences among each national database referring to any single species. This includes a lack of information about the number of rabbit farms and the number of farmed rabbits or the number of farmed fish in each single aquaculture farm. Moreover, different animal identification systems, which are more specific in cattle compared to other species – especially sheep or poultry, ensure a greater reliability of cattle BDN with respect to others. General descriptive studies regarding drug use are important as a reference point for planning further studies and strategies that address antibiotic resistance and improper drug usage. In our consideration of drug prescriptions, no information about the diagnosis stating whether antimicrobial susceptibility tests were used to select the antimicrobial of choice were reported. This made it difficult to assess the appropriateness of the prescribed therapy and its compliance with prudent principle usage (European Commission 2015). Conclusion The description of veterinary drug usage through a DDDvet_Umbria approach, allowed us to overcome the limits of the report of national sales of veterinary antimicrobials produced annually by the EMA/ 314 Veterinary antimicrobial prescriptions in Umbria Scoppetta et al. Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 animals, and enables the identification of problem farms where controls could be carried out. Our results highlight this critical area of drug consumption. Moreover results of this study suggest that the spread of antibiotic resistance in veterinary medicine could include swine, poultry, and rainbow trout farms, where the highest use of antibiotics and, in particular, CIAs, was observed. This data could additionally be particularly useful in guiding the implementation of plans to reduce any irrational use of antibiotics and veterinary drugs, promoting prevention by using vaccines, and improving farm management by improving knowledge on antibiotic resistance and responsible use of antibiotic drugs in veterinary medicine. ESVAC. Moreover, it facilitated drug consumption comparisons between human and veterinary medicines, especially insomuch as they related to antibiotics and CIAs. It should be noted that the non-computerisation of veterinary prescriptions makes it more difficult to analyse antibiotic consumption in veterinary medicine; for example, some prescriptions could have been missed in the data transmission system. This underlines the necessity for the implementation of electronic prescriptions in veterinary medicine in order to obtain complete data more rapidly. Making data available is useful for carrying out risk assessments based on drug consumption – especially antimicrobials – in food producing Agenzia Italiana Farmaco 2016. Osservatorio Nazionale sull’impiego dei Medicinali. L’uso dei farmaci in Italia. Rapporto Nazionale 2015. http://www.aifa.gov.it/sites/ default/files/Rapporto_OsMed_2015_AIFA-acc.pdf. AURES. Resistenzbericht Österreich AURES 2012 - Antibiotikaresistenz und Verbrauch antimikrobieller Substanzen in Österreich. Wien: Bundesministerium für Gesundheit. 2013; 397. Bowen I.M. & Clegg P.D. 2015. Antimicrobial resistance in the horse. Equine Vet J, 47, 745-746. Callens B., Persoons D., Maes D., Laanen M., Postma M., Boyen F., Haesebrouck F., Butaye P., Catry B. & Dewulf J. 2012. Prophylactic and metaphylactic antimicrobial use in Belgian fattening pig herds. Prev Vet Med, 106, 53-62. Catry B., Laevens H., Devriese L.A., Opsomer G. & De Kruif A. 2003. Antimicrobial resistance in livestock. J Vet Pharmacol Ther, 26, 81-93. Collineau L., Belloc C., Stärk K.D., Hémonic A., Postma M., Dewulf J. & Chauvin C. 2017. Guidance on the selection of appropriate indicators for quantification of antimicrobial usage in humans and animals. Zoonoses Public Health, 64 (3),165-184. DANMAP. 2014. Use of antimicrobial agents and occurrence of antimicrobial resistance in bacteria from Food animals, food and humans in Denmark. Soborg, Denmark: National Food Institute, Technical University of Denmark; Microbiology and Infection Control, Statens Serum Institute. September 2015. Report, 112 pp. De Briyne N., Atkinson J., Pokludová L. & Borriello S.P. 2014. Antibiotics used most commonly to treat animals in Europe. Vet Rec, 175, 325. Di Cesare A., Luna G.M., Vignaroli C., Pasquaroli S., Tota S., Paroncini P. & Biavasco F. 2013. Aquaculture can promote the presence and spread of antibiotic-resistant Enterococci in marine sediments. PLoS One, 8, 62838. References Economou V. & Gousia P. 2015. Agriculture and food animals as a source of antimicrobial-resistant bacteria. Infect Drug Resist, 8, 49-61. European Commission (EC) 2003. Directive 2003/99/ EC of the European Parliament and of the Council on the monitoring of zoonoses and zoonotic agents, amending Council Decision 90/424/EEC and repealing Council Directive 92/117/EEC. Off J, L 325. European Commission (EC) 2003. Europe. Regulation (EC) No. 1831/2003 of the European Parliament and of the Council on additives for use in animal nutrition. Off J, L 268. European Commission (EC) 2006. Council directive 2005/94/EC of 20 December 2005 on Community measures for the control of avian influenza and repealing Directive 92/40/EEC. Off J, L 10. European Commission (EC) 2015. Commission Notice 2015/C 299/04 - Guidelines for the prudent use of antimicrobials in veterinary medicine. Off J, C 299. European Food Safety Authority (EFSA) 2016. The European Union summary report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2014. EFSA Journal, 14, 207. European Medicine Agency (EMA) 2013. Revised ESVAC reflection paper on collecting data on consumption of antimicrobial agents per animal species, on technical units of measurement and indicators for reporting consumption of antimicrobial agents in animals. EMA/286416/2012-Rev.1. European Medicine Agency (EMA) 2013. Use of colistin products in animals within the European Union: development of resistance and possible impact on human and animal health. EMA/755938/2012. European Medicine Agency (EMA) 2015. Principles on assignment of defined daily dose for animals (DDDvet_ Umbria) and defined course dose for animals (DCDvet) Veterinary Medicines Division. EMA/710019/2014. 315 Scoppetta et al. Veterinary antimicrobial prescriptions in Umbria Veterinaria Italiana 2018, 54 (4), 305-315. doi: 10.12834/VetIt.1174.6524.2 Dewulf J.; MINAPIG Consortium. 2015. Assigning defined daily doses animal: a European multi-country experience for antimicrobial products authorized for usage in pigs. J Antimicrob Chemother, 70, 294-302. Rajala-Schultz P.J., Torres A.H., Degraves F.J., Gebreyes W.A. & Patchanee P. 2009. Antimicrobial resistance and genotypic characterization of coagulase-negative staphylococci over the dry period. Vet Microbiol, 134, 55-64. Santman-Berends I., Luttikholt S., Van den Brom R., Van Schaik G., Gonggrijp M., Hage H. & Vellema P. 2014. Estimation of the use of antibiotics in the small ruminant industry in The Netherlands in 2011 and 2012. PLoS One, 12, 9(8), e105052. Scoppetta F., Cenci T., Valiani A., Galarini R. & Capuccella M. 2016. Qualitative survey on antibiotic use for mastitis and antibiotic residues in Umbrian dairy herds. Large Animal Review, 22, 11-18. Silbergeld E.K., Graham J. & Price L.B. 2008. Industrial food animal production, antimicrobial resistance, and human health. Annu Rev Public Health, 29, 151-169. SVARM. 2012. Swedish Veterinary Antimicrobial Resistance Monitoring. Solna/Upplala, Sweden: Swedish Institute for Communicable Disease Control and National Veterinary Institute. Timmerman T., Dewulf J., Catry B., Feyen B., Opsomer G., de Kruif A. & Maes D. 2006. Quantification and evaluation of antimicrobial drug use in group treatments for fattening pigs in Belgium. Prev Vet Med, 16, 251-263. Trauffler M., Obritzhauser W., Raith J., Fuchs K. & Köfer J. 2014. The use of the "highest priority critically important antimicrobials" in 75 Austrian pig farms - Evaluation of on-farm drug application data. Berl Munch Tierarztl Wochenschr, 127, 375-383. van Rennings L., von Münchhausen C., Ottilie H., Hartmann M., Merle R., Honscha W., Käsbohrer A. & Kreienbrock L. 2015. Cross-sectional study on antibiotic usage in pigs in Germany. PLoS One, 10 (3), e0119114. Wassenaar T.M. 2005. Use of antimicrobial agents in veterinary medicine and implications for human health. Crit Rev Microbiol, 31, 155-169. Weese J.S. 2015. Antimicrobial use and antimicrobial resistance in horses. Equine Vet J, 47, 747-749. World Health Organization (WHO). 2011. WHO Critically Important Antimicrobials for Human Medicine: 3rd Revision 2011. Oslo: WHO World Health Organization Advisory Group on Integrated Surveillance of Antimicrobial Resistance (AGISAR). 2011, 38. World Health Organization (WHO). 2013. ATC/DDD Index 2013. Oslo: Collaborating Centre for Drug Statistics Methodology, Norwegian Institute of Public Health. Zonca A. & Cagnardi P. 2012. Impatto ambientale dei farmaci veterinari in acquacoltura. Summa (Animali da Reddito), 5, 35-42. European Medicine Agency (EMA) 2016. EMA advice on use of colistin in animals to be updated - EMA acts upon request from European Commission following detection of colistin-resistant bacteria. EMA/ CVMP/832098/2015. European Medicine Agency/European Surveillance of Veterinary Antimicrobial Consumption (EMA/ESVAC) 2015. Sales of veterinary antimicrobial agents in 26 EU/EEA countries in 2013 - Fifth ESVAC report. EMA/387934/2015. Report, 172 pp. European Medicine Agency/European Surveillance of Veterinary Antimicrobial Consumption (EMA/ESVAC) 2016. Defined daily doses for animals (DDDvet) and defined course doses for animals (DCDvet). EMA/224954/2016. González S.M., Steiner A., Gassner B. & Regula G. 2010. Antimicrobial use in Swiss dairy farms: quantification and evaluation of data quality. Prev Vet Med, 95, 50-63. Lanza G., Faccini F., Valdonio M., Arrigoni N., Pattarini P., Grilli B., Cabrini E., Boccellino M. & Delledonne M. 2015. Consumo e modalità d’impiego degli antibatterici nell’allevamento di bovine da latte della provincia di Piacenza. Large Animal Review, 21, 51-60. Lim S.J., Jang E., Lee S.H., Yoo B.H., Kim S.K. & Kim T.H. 2013. Antibiotic resistance in bacteria isolated from freshwater aquacultures and prediction of the persistence and toxicity of antimicrobials in the aquatic environment. J Environ Sci Health B, 48, 495-504. Mancini L., Aulicino F.A., Marcheggiani S., D'Angelo A.M., Pierdominici E., Puccinelli C., Scenati R. & Tancioni L.2010. Multi-criteria approach for the environmental impact assessment of inland aquaculture. Ann Ist Super Sanita, 46, 317-322. MARAN. 2015. Monitoring of Antimicrobial Resistance and Antibiotic Usage in Animals in the Netherlands in 2014. Lelystad, Netherlands: Central Veterinary Institute, part of Wageningen University and Research Centre (CVI), 2015; June 2015. Report, 72 pp. Merle R., Robanus M., Hegger-Gravenhorst C., Mollenhauer Y., Hajek P., Käsbohrer A., Honscha W. & Kreienbrock L. 2014. Feasibility study of veterinary antibiotic consumption in Germany - Comparison of ADDs and UDDs by animal production type, antimicrobial class and indication. BMC Vet Res, 10, 7. Ministero della Salute. Dipartimento della sanità pubblica veterinaria, della sicurezza alimentare e degli organi collegiali per la tutela della salute direzione generale della sanità animale e dei farmaci veterinari. 2012. Manuale di Biosicurezza e uso corretto e razionale degli antibiotici in zootecnia, Roma, Ministero della Salute. Persoons D., Dewulf J., Smet A., Herman L., Heyndrickx M., Martel A., Catry B., Butaye P. & Haesebrouck F. 2012. Antimicrobial use in Belgian broiler production. Prev Vet Med, 105, 320-325. Postma M., Sjölund M., Collineau L., Lösken S., Stärk K.D.,