Administering intramammary antimicrobials to all mammary quarters of dairy cows at drying-off i.e., blanket dry cow therapy (BDCT) has been a mainstay of mastitis prevention and control. However, as ...udder health has considerably improved over recent decades with reductions in intramammary infection prevalence at drying-off and the introduction of teat sealants, BDCT may no longer be necessary on all dairy farms, thereby supporting antimicrobial stewardship efforts. This narrative review summarizes available literature regarding current dry cow therapy practices and associated impacts of selective dry cow therapy (SDCT) on udder health, milk production, economics, antimicrobial use, and antimicrobial resistance. Various methods to identify infections at drying-off that could benefit from antimicrobial treatment are described for selecting cows or mammary quarters for treatment, including utilizing somatic cell count thresholds, pathogen identification, previous clinical mastitis history, or a combination of criteria. Selection methods may be enacted at the herd, cow, or quarter levels. Producers' and veterinarians' motivations for antimicrobial use are discussed. Based on review findings, SDCT can be adopted without negative consequences for udder health and milk production, and concurrent teat sealant use is recommended, especially in udder quarters receiving no intramammary antimicrobials. Furthermore, herd selection should be considered for SDCT implementation in addition to cow or quarter selection, as BDCT may still be temporarily necessary in some herds for optimal mastitis control. Costs and benefits of SDCT vary among herds, whereas impacts on antimicrobial resistance remain unclear. In summary, SDCT is a viable management option for maintaining udder health and milk production while improving antimicrobial stewardship in the dairy industry.
Although milk and dairy products are important components of a healthy diet, if consumed unpasteurized, they also can present a health hazard due to possible contamination with pathogenic bacteria. ...These bacteria can originate even from clinically healthy animals from which milk is derived or from environmental contamination occurring during collection and storage of milk. The decreased frequency of bovine carriage of certain zoonotic pathogens and improved milking hygiene have contributed considerably to decreased contamination of milk but have not, and cannot, fully eliminate the risk of milkborne disease. Pasteurization is the most effective method of enhancing the microbiological safety of milk. The consumption of milk that is not pasteurized increases the risk of contracting disease from a foodstuff that is otherwise very nutritious and healthy. Despite concerns to the contrary, pasteurization does not change the nutritional value of milk. Understanding the science behind this controversial and highly debated topic will provide public health care workers the information needed to discern fact from fiction and will provide a tool to enhance communication with clients in an effort to reduce the incidence of infections associated with the consumption of unpasteurized milk and dairy products.
Background
Primary secretory otitis media (PSOM) in the cavalier King Charles spaniel (CKCS) is similar to otitis media with effusion (OME) in humans. A proposed aetiology of OME is inflammation of ...the middle ear mucosa, usually due to bacterial infection, leading to auditory tube dysfunction.
Hypothesis/Objectives
Our objective was to characterize the microbiological and cytological findings of otic exudates from the external ear canal (EEC) (n = 68) and middle ear (ME) (n = 69) from 41 CKCSs with PSOM.
Methods and materials
Swab samples from the EEC and mucus aspirated from the ME after performing a myringotomy were obtained for bacterial culture and cytological analysis.
Results
Fifty‐five of 68 (81%) EEC and 46 of 69 (67%) ME yielded no bacterial growth. Thirty‐eight of the 68 (56%) ears had no microbial growth from neither the EEC nor ME; seven (10%) had bacteria isolated from the EEC only; 17 (25%) had bacteria isolated from the ME only, and six (8%) had bacteria isolated from both EEC and ME. Thirty‐four total bacterial isolates were cultured from ME. The most common bacterial species isolated were coagulase‐negative staphylococci, followed by Staphylococcus pseudintermedius. Otic cytology identified coccoid organisms in only three of 68 EEC and four of 69 ME.
Conclusions
The role of bacteria in the pathogenesis of PSOM in CKCS is unclear. The majority of the EEC and ME of the CKCS with PSOM were negative by conventional bacterial culture and the cytological presence of bacteria was not correlated with culture positives. The potential role of noncultivable microbiota in PSOM requires exploration using molecular methods.
Résumé
Contexte
L'otite moyenne sécrétante primaire (PSOM) du cavalier king charles spaniel (CKCS) est similaire à l'otite moyenne avec effusion (OME) de l'homme. Une étiologie proposée de l’OME est une inflammation de la muqueuse de l'oreille moyenne, usuellement due à une infection bactérienne menant à un dysfonctionnement du canal auditif.
Hypothèses/Objectifs
Notre objectif était de caractériser les données cytologiques et microbiologiques d'exsudats auriculaires des conduits auriculaires externes (EEC) (n=68) et de l'oreille moyenne (ME) (n=69) de 41 chiens CKCS avec PSOM.
Matériel et méthode
Des écouvillons de EEC et du mucus aspiré de ME après myringotomie ont été obtenus pour culture bactériologique et analyse cytologique.
Résultats
Cinquante cinq des 68 (81%) EEC et 46 des 69 (67%) ME n'ont pas permis de croissance bactérienne. Trente huit des 68 (56%) oreilles n'avaient pas de croissance bactérienne ni de EEC ni de ME; sept (10%) avaient une bactérie isolée de EEC seulement; 17 (25%) avaient des bactéries isolées de ME seulement et six (8%) avaient des bactéries isolées à la fois de EEC et de ME. Trente quatre souches bactériennes totales ont été cultivées de ME. L'espèce bactérienne la plus fréquemment isolée était un staphylocoque coagulase‐négatif suivi de Staphylococcus pseudintermedius. La cytologie auriculaire a identifié des organismes coccoïdes dans seulement trois des 68 EEC et quatre des 69 ME.
Conclusions
Le rôle bactérien dans la pathogénie de PSOM du CKCS n'est pas clair. La majorité des EEC et ME des CKCS avec PSOM était négative par les cultures bactériologiques conventionnelles et la présence cytologique de bactérie n’était pas corrélée aux cultures positives. Le rôle potentiel du microbiote non cultivable des PSOM nécessite l'exploration à l'aide de méthodes moléculaires.
Resumen
Introducción
la otitis media secretora primaria (PSOM) en perros de raza Cavalier King Charles Spaniel (CKCS) es similar a la otitis media con derrame (OME) en humanos. Una etiología propuesta de la OME es la inflamación de la mucosa del oído medio, generalmente debido a una infección bacteriana, que conduce a una disfunción del canal auditivo.
Hipótesis/Objetivos
nuestro objetivo fue caracterizar los hallazgos microbiológicos y citológicos de exudados óticos del canal auditivo externo (EEC) (n = 68) y el oído medio (ME) (n = 69) de 41 CKCS con PSOM.
Métodos y materiales
se obtuvieron muestras con hisopo del EEC y mucosidad aspirada de la ME después de realizar una miringotomía para cultivo bacteriano y análisis citológico.
Resultados
cincuenta y cinco de 68 (81%) de muestras del CEE y 46 de 69 (67%) del ME no produjeron crecimiento bacteriano. Treinta y ocho de los 68 oídos (56%) no tuvieron crecimiento microbiano ni del EEC ni del ME; siete (10%) presentaron aislados bacterianos solo del CEE; 17 (25%) mostraron bacterias aisladas solo del ME, y seis (8%) tuvieron bacterias aisladas tanto del EEC como del ME. Treinta y cuatro aislamientos bacterianos totales se cultivaron a partir del ME. Las especies bacterianas más comunes aisladas fueron estafilococos coagulasa negativos, seguidos de Staphylococcus pseudintermedius. La citología ótica identificó los organismos cocoides en solo tres de 68 muestras d
el EEC y cuatro de 69 del ME.
Conclusionesel papel de las bacterias en la patogénesis de la PSOM en CKCS no está claro. La mayoría de las muestras del EEC y del ME de CKCS con PSOM fueron negativas en cultivo bacteriano convencional y la presencia citológica de bacterias no se correlacionó con los positivos del cultivo. El papel potencial de la microbiota no cultivable en PSOM requiere estudios utilizando métodos moleculares.
Zusammenfassung
Hintergrund
Die primäre sekretorische Otitis media (PSOM) beim Cavalier King Charles Spaniel (CKCS) ist einer Otitis media mit Effusion (OME) beim Menschen ähnlich. Die vermeintliche Ätiologie einer OME ist eine Entzündung der Mittelohrmukosa, üblicherweise durch eine bakterielle Infektion, die zu einer Gehörkanal Dysfunktion führt.
Hypothese/Ziele
Unser Ziel war es, die mikrobiellen und zytologischen Befunde von Ohrexsudaten aus dem äußeren Ohrkanal (EEC)(n = 68) und Mittelohr (ME)(n = 69) von 41 CKCSs mit PSOM zu charakterisieren.
Methoden und Material
Tupferproben vom EEC und aspirierter Schleim vom ME nach Durchführung einer Myringotomy wurden zur Bakterienkultur und zytologischen Analyse entnommen.
Ergebnisse
Fünfundfünfzig von 68 (81%) EEC und 46 von 69 (67%) ME ergaben kein Bakterienwachstum. Achtunddreißig von 68 (56%) Ohren zeigten kein mikrobielles Wachstum, weder aus dem EEC noch aus dem ME; bei sieben (10%) konnten Bakterien nur aus dem EEC isoliert werden; bei 17 (25%) konnten Bakterien nur aus dem ME isoliert werden, und bei sechs (8%) wurden Bakterien sowohl vom EEC wie auch aus dem ME isoliert. Insgesamt wurden vierunddreißig Bakterienisolate aus dem ME kultiviert. Die häufigste Bakterienspezies, die nachgewiesen werden konnte, waren Koagulase‐negative Staphylokokken, gefolgt von Staphylococcus pseudintermedius. Mittels Zytologie aus dem Ohr wurden kokkoide Organismen in nur drei von 68 EEC und vier von 69 ME nachgewiesen.
Schlussfolgerungen
Die Rolle der Bakterien in der Pathogenese der PSOM beim CKCS ist unklar. Die Mehrheit der EEC und ME der CKCS mit PSOM waren mit konventioneller Bakterienkultur negativ und das zytologische Auftreten der Bakterien war nicht mit den positiven Kulturen korreliert. Die mögliche Rolle von nicht kultivierbaren Mikrobiota bei PSOM sollte mittels molekularer Methoden durchleuchtet werden.
要約
背景
キャバリア・キング・チャールズ・スパニエル(CKCS)の原発性滲出性中耳炎(PSOM)は、人の滲出性中耳炎(OME)と似ている。提案されているOMEの病因としては、通常は細菌感染による中耳粘膜の炎症であり、これは聴覚管機能不全につながる。
仮説/目的
本研究の目的は、PSOMを有するCKCS41頭の外耳道(EEC)(n =68 )および中耳(ME)(n = 69)から得た耳滲出液の微生物学的および細胞学的所見を特徴付けることであった。
材料および方法
EECから採取したスワブサンプルおよび鼓膜切開術実施後MEから吸引した粘液を細菌培養および細胞学的解析のために得た。
結果
68のうち55 のEEC(81%)および69のうち46 のME(67%)は細菌増殖を生じなかった。 68のうち38の耳(56%)ではEECおよびMEのどちらにおいても細菌増殖を生じなかった。 7つの耳(10%)がEECのみ細菌を分離した。 17の耳(25%)がMEのみ分離された細菌を保有し、6の耳(8%)がEECとMEの両方から分離された細菌を保有していた。合計34の細菌分離株をMEから培養した。単離された最も一般的な細菌種は、コアグラーゼ陰性ブドウ球菌、続いてStaphylococcus pseudintermediusであった。耳垢細胞診では、68のうち3つのEECおよび69のうち4つの MEのみ球菌様微生物を同定した。
結論
CKCSのPSOM病因に対する細菌の役割は不明である。 PSOMを有するCKCSのEECおよびMEの大部分は、従来の細菌培養によって陰性であり、細菌の細胞学的存在は培養陽性と相関していなかった。 PSOMにおける培養不可能な微生物叢の潜在的な役割は、分子法を用いた探査を必要とする。
Resumo
Contexto
A otite média secretória primária (PSOM) nos cães da raça cavalier King Charles spaniel (CKCS) é similar à otite média com efusão (OME) em humanos. A etiologia proposta da OME é a inflamação da mucosa da orelha média, usualmente devido à infecção bacteriana, levando à disfunção da tuba auditiva.
Hipótese/Objetivos
Nosso objetivo foi caracterizar os achados microbiológicos e citológicos de exsudatos óticos de conduto auditivo externo (CAE) (n = 68) e ouvido médio (OM) (n = 69) de 41 CKCSs com PSOM.
Métodos e materiais
Amostras por swabs de CAE e muco aspirado de OM pós miringotomia foram obtidos para culturas bacterianas e análises citológicas.
Resultados
Cinquenta e cinco de 68 (81%) dos CAE e 46 de 69 (67%) dos OM não demonstraram crescimento bacteriano. Trinta e oito de 68 (56%) das orelhas não apresentaram nenhum crescimento bacteriano nas amostras oriundas de CAE, bem como das amostras de OM; sete (10%) apresentaram bactérias isoladas apenas no CAE; 17 (25%) apresentaram bactérias isoladas do OM apenas, e seis (8%) apresentaram bactérias isoladas de CAE e OM. Trinta e quatro isolados bacterianos no total foram cultivados do OM. As espécies bacterianas mais comumente isoladas foram os estafilococos coagulase‐negativos, seguido de Staphylococcus pseudintermedius. Citologia otológica identificou microrganismos cocoides em apenas três dos 68 CAE e 69 OM.
Conclusões
A função das bactérias na patogênese da PSOM em CKCS não está esclarecida. A maioria dos CAE e OM de CKCS com PSOM foram negativos por métodos de cultura convencionais e não houve correlação entre a presença citológica de bactérias e as culturas positivas. A potencial função da microbiota não‐cultivável no PSOM requer exploração por métodos moleculares.
Background ‐ Primary secretory otitis media (PSOM) in the cavalier King Charles spaniel (CKCS) is similar to otitis media with effusion (OME) in humans. A proposed aetiology of OME is inflammation of the middle ear mucosa, usually due to bacterial i
Treatment of clinical mastitis (CM) and use of antimicrobials for dry cow therapy are responsible for the majority of animal-defined daily doses of antimicrobial use (AMU) on dairy farms. However, ...advancements made in the last decade have enabled excluding nonsevere CM cases from antimicrobial treatment that have a high probability of cure without antimicrobials (no bacterial causes or gram-negative, excluding Klebsiella spp.) and cases with a low bacteriological cure rate (chronic cases). These advancements include availability of rapid diagnostic tests and improved udder health management practices, which reduced the incidence and infection pressure of contagious CM pathogens. This review informed an evidence-based protocol for selective CM treatment decisions based on a combination of rapid diagnostic test results, review of somatic cell count and CM records, and elucidated consequences in terms of udder health, AMU, and farm economics. Relatively fast identification of the causative agent is the most important factor in selective CM treatment protocols. Many reported studies did not indicate detrimental udder health consequences (e.g., reduced clinical or bacteriological cures, increased somatic cell count, increased culling rate, or increased recurrence of CM later in lactation) after initiating selective CM treatment protocols using on-farm testing. The magnitude of AMU reduction following a selective CM treatment protocol implementation depended on the causal pathogen distribution and protocol characteristics. Uptake of selective treatment of nonsevere CM cases differs across regions and is dependent on management systems and adoption of udder health programs. No economic losses or animal welfare issues are expected when adopting a selective versus blanket CM treatment protocol. Therefore, selective CM treatment of nonsevere cases can be a practical tool to aid AMU reduction on dairy farms.
Treatment of clinical mastitis (CM) contributes to antimicrobial use on dairy farms. Selective treatment of CM based on bacterial diagnosis can reduce antimicrobial use, as not all cases of CM will ...benefit from antimicrobial treatment, e.g., mild and moderate gram-negative infections. However, impacts of selective CM treatment on udder health and culling are not fully understood. A systematic search identified 13 studies that compared selective versus blanket CM treatment protocols. Reported outcomes were synthesized with random-effects models and presented as risk ratios or mean differences. Selective CM treatment protocol was not inferior to blanket CM treatment protocol for the outcome bacteriological cure. Noninferiority margins could not be established for the outcomes clinical cure, new intramammary infection, somatic cell count, milk yield, recurrence, or culling. However, no differences were detected between selective and blanket CM treatment protocols using traditional analyses, apart from a not clinically relevant increase in interval from treatment to clinical cure (0.4 d) in the selective group and higher proportion of clinical cure at 14 d in the selective group. The latter occurred in studies co-administering nonsteroidal anti-inflammatories only in the selective group. Bias could not be ruled out in most studies due to suboptimal randomization, although this would likely only affect subjective outcomes such as clinical cure. Hence, findings were supported by a high or moderate certainty of evidence for all outcome measures except clinical cure. In conclusion, this review supported the assertion that a selective CM treatment protocol can be adopted without adversely influencing bacteriological and clinical cure, somatic cell count, milk yield, and incidence of recurrence or culling.
Digital dermatitis (DD) is a severe bacterial hoof disease found worldwide. The disease can be classified into 5 different stages, denoted as M1 to M4 and M4.1, by clinical examination. The main ...objective of this study was to estimate prevalence of DD lesions in Finnish freestall dairy cattle population through hind feet inspection of standing cows with a mirror. Another aim was to estimate the sensitivity and specificity of mirror scoring on standing cows in a pen or in a milking parlor without washing the feet. Three veterinarians visited 81 randomly selected herds across the country. During the herd visits, hind feet of standing cows (n = 7,010) were scored with a mirror without washing the feet, either when the cows were standing in a pen (n = 4,992) or in the milking parlor (n = 2018). In total, 128 cows (111 from pen and 17 from milking parlor) including 256 feet were chosen with cross-sectional sampling and scored in a trimming chute. Animal-level sensitivity for scoring M2 lesions with a mirror was 55% and specificity was 97%; for all active DD lesions (M1, M2, or M4.1), sensitivity was 36% and specificity was 96%. Sensitivity for scoring any DD lesions was 90% and specificity was 82%. The bias-corrected sensitivity and specificity for scoring any DD lesions were 79% and 92%, respectively. The bias-corrected sensitivity and specificity for scoring M2 DD lesions were 10% and 100%. We found M2 lesions in 12.1% of the study herds, and true herd-level prevalence was the same. Altogether, 33.3% (true prevalence 28.4%) of the herds had either M1, M2, or M4.1 DD lesions. However, only 0.7% (true prevalence 5.4%) of cows in total had active M2 lesions. The within-herd prevalence of M2 lesions (in herds where at least 1 cow had a M2 lesion) was 5.7% and varied between 0.4% and 18.8%. Herds with active DD lesions also had more any DD lesions than herds without active DD lesions. The herd-level prevalence was higher than previously thought, with only 1 herd without any DD lesions. However, the animal-level prevalence of active DD lesions was relatively low. Farmers and veterinarians need to be informed of the disease and possible control measures. Because of the low within-herd prevalence, the control of the disease might be easier than in countries where DD is widespread. Further studies are needed to identify factors associated with DD prevalence in Finnish dairy herds.
Gastrointestinal parasites, Parascaris sp. and strongyles, are common in young horses worldwide and control of these parasites is challenged by increasing anthelmintic resistance. Our aim was to ...identify risk factors for these infections as well as to assess the efficacy of fenbendazole (dose 7.5 mg/kg) and pyrantel embonate (dose 19 mg/kg) against Parascaris sp. We also evaluated association between owner observed symptoms and patent infections with these parasites. Fecal samples were collected from 367 young horses in Finland and a questionnaire study was conducted. Fecal egg counts were performed by Mini-FLOTAC® method. Univariable logistic regression models using patent infection status (Yes/No), separately for Parascaris sp. and strongyle infections as an outcome were run initially to screen potential risk factors collected by the questionnaire. After the initial screening, multiple logistic regression models were constructed and run to account for correlated data structure, risk factors and potential confounders simultaneously. Two significant risk factors for a patent Parascaris sp. infection were found: breeding farm size (p = 0.028) and frequency of horse movements (p = 0.010). Horses originating from large breeding farms were more likely (OR = 2.47, 95% confidence interval (CI) 1.10-5.51) to shed Parascaris sp. eggs upon relocation to training stables compared to horses originating from small breeding farms. Horses living in farms with frequent horse movements to other premises had higher odds (OR = 3.56, 95% CI: 1.35-9.39) of a patent Parascaris sp. infection compared to farms with less frequent horse movements. Risk factors for patent strongyle infection included age (p < 0.001) and season (p = 0.017). Horses were less likely (OR = 0.27, 95% CI: 0.10 - 0.66) to shed strongylid eggs during the spring compared to the winter. Horses excreting over 200 ascarid eggs per gram were included in the anthelmintic efficacy trial. A mean FECR less than 90% was interpreted as presence of anthelmintic resistance. The mean FECR was 98.5% (95% CI: 95.8-100) and 68.0% (95% CI: 52.7-83.3) in the fenbendazole (n = 31) and pyrantel (n = 26) treatment groups, respectively. In conclusion, we identified two new risk factors for patent Parascaris sp. infection; breeding farm size and frequency of horse movements. Reduced efficacy of pyrantel against Parascaris sp. was observed for the second time in Europe. A relatively high Parascaris sp. prevalence in yearlings (34%) and two-year-olds (20%) was observed, which has not been reported earlier. An association between symptoms and a patent Parascaris sp. infection was observed in foals.
The most frequent reason for antimicrobial use in dairy herds is mastitis and knowledge about mastitis-causing pathogens and their antimicrobial susceptibility should guide treatment decisions. The ...overall objective of this study was to assess antimicrobial resistance (AMR) of staphylococci in mastitic milk samples in Finland. MALDI-ToF MS identified a total of 504
Staphylococcus
isolates (260
S. aureus
and 244 non-aureus staphylococci, NAS) originating from bovine mastitic milk samples. Phenotypic susceptibility against cefoxitin, ceftiofur, enrofloxacin, gentamycin, oxacillin, penicillin, and tetracycline was evaluated by disk diffusion method and the presence of
blaZ
,
mecA
, and
mecC
genes investigated by PCR. Nitrocefin test assessed these isolates’ beta-lactamase production. The most common NAS species were
S. simulans, S. epidermidis, S. chromogenes,
and
S. haemolyticus.
In total, 26.6% of the isolates (18.5% of
S. aureus
and 35.2% of all NAS) carried the
blaZ
gene. Penicillin resistance, based on disk diffusion, was lower: 18.8% of all the isolates (9.3% of
S. aureus
and 28.9% of all NAS) were resistant. Based on the nitrocefin test, 21.5% of the isolates produced beta-lactamase (11.6% of
S. aureus
and 32.0% of all NAS). Between the
Staphylococcus
species, the proportion of penicillin-resistant isolates varied, being lowest in
S. simulans
and highest in
S. epidermidis.
Resistance to antimicrobials other than penicillin was rare. Of the eight NAS isolates carrying the
mecA
gene, six were
S. epidermidis
. One
S. aureus
isolate carried the
mecC
gene. Agreement beyond chance, assessed by kappa coefficient, between phenotypic and genotypic resistance tests, was moderate to substantial. Some phenotypically penicillin-susceptible staphylococci carried the
blaZ
gene but isolates without
blaZ
or
mec
genes rarely exhibited resistance, suggesting that the more reliable treatment choice may depend upon genotypic AMR testing. Our results support earlier findings that penicillin resistance is the only significant form of antimicrobial resistance among mastitis-causing staphylococci in Finland.
Selective dry cow therapy (SDCT) has received increasing attention in recent years owing to global concerns over agricultural use of antimicrobial drugs and development of antimicrobial resistance. ...The objective of this study was to evaluate the effect of SDCT on milk yield and somatic cell count (SCC) in dairy herds in the USA. Cows in four Ohio dairy herds were categorized into two groups (low-SCC and high-SCC) at dry-off based on their SCC and clinical mastitis (CM) history during the lactation preceding the dry-off. Low-SCC cows were randomly assigned to receive or not to receive intramammary antibiotics at dry-off. Milk yield and SCC of these cows during the following lactation were compared using linear mixed effects models, adjusting for parity, calving season, stage of lactation, previous lactation milk yield and herd. Milk yield of untreated and treated low-SCC cows at dry-off did not differ significantly during the following lactation. Overall, treated low-SCC cows had 16% lower SCC (approximately 35 000 cells/ml, P=0·0267) than the untreated cows during the following lactation; however, the effect was variable in different herds. Moreover the impact of treatment, or the lack thereof, on milk yield varied considerably between herds. The results suggested that in some herds treating all cows at dry-off may be beneficial while in other herds leaving healthy cows without antibiotic dry cow treatment has no negative impact on milk yield or milk quality (SCC), and in fact, may be beneficial. Further studies are needed to identify characteristics of herds where treating all cows routinely at dry-off may be needed for maintaining good udder health and where switching to selective treatment of cows at dry-off would be the optimal approach to achieve best results.
OBJECTIVE To identify the geographic distribution of exhibition swine in the Midwestern United States, characterize management practices used for exhibition swine, and identify associations between ...those practices and influenza A virus (IAV) detection in exhibition swine arriving at county or state agricultural fairs. DESIGN Cross-sectional survey. SAMPLE 480 swine exhibitors and 641 exhibition swine. PROCEDURES Inventories of swine exhibited at fairs in 6 selected Midwestern states during 2013 and of the total swine population (including commercial swine) in these regions in 2012 were obtained and mapped. In 2014, snout wipe samples were collected from swine on arrival at 9 selected fairs in Indiana (n = 5) and Ohio (4) and tested for the presence of IAV. Also at fair arrival, swine exhibitors completed a survey regarding swine management practices. RESULTS Contrary to the total swine population, the exhibition swine population was heavily concentrated in Indiana and Ohio. Many swine exhibitors reported attending multiple exhibitions within a season (median number, 2; range, 0 to 50), with exhibited swine often returned to their farm of origin. Rearing of commercial and exhibition swine on the same premises was reported by 13.3% (56/422) of exhibitors. Hosting an on-farm open house or sale was associated with an increased odds of IAV detection in snout wipe samples. CONCLUSIONS AND CLINICAL RELEVANCE The exhibition swine population was highly variable and differed from the commercial swine population in terms of pig density across geographic locations, population integrity, and on-farm management practices. Exhibition swine may be important in IAV transmission, and identified biosecurity deficiencies may have important public and animal health consequences.