{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T12:21:03Z","timestamp":1788265263148,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003196","name":"Ministero della Salute","doi-asserted-by":"publisher","award":["IZSVe RC 01\/2022"],"award-info":[{"award-number":["IZSVe RC 01\/2022"]}],"id":[{"id":"10.13039\/501100003196","id-type":"DOI","asserted-by":"publisher"}]},{"award":["IZSVe RC 01\/2022"],"award-info":[{"award-number":["IZSVe RC 01\/2022"]}],"id":[{"id":"https:\/\/ror.org\/00789fa95","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Reducing antimicrobial use in dairy cattle requires practical methods to identify cows that need antimicrobial treatment at dry-off. The objective of this study was to develop and evaluate a classification model using on-farm indirect indicators as a first step toward identifying cows with intramammary infection (IMI) at dry-off. The study was conducted on a single commercial dairy farm and included 301 cows. Quarter milk samples were collected before dry-off and used as the reference method to define IMI. Cow-level predictors included somatic cell count (SCC) history, clinical mastitis history, parity, teat health score, and genetic values for SCC, which were combined in a multivariable logistic regression model internally validated using a 75\/25 training-testing split. Overall, 1190 quarters were examined, and 129 cows were classified as infected with at least one major mammary pathogen at dry-off. The best-performing model included genetic value for SCC, linear score at selected test days, and clinical mastitis history, reaching an accuracy of 0.75 (0.64\u20130.84), a sensitivity of 0.80 (0.63\u20130.92), a specificity of 0.71 (0.55\u20130.84), and an AUC of 0.76 (0.65\u20130.87). These results suggest that combining indirect cow-level indicators may support treatment allocation at dry-off, although external validation across multiple herds is required.<\/jats:p>","DOI":"10.3390\/ani16172719","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T11:33:32Z","timestamp":1788262412000},"page":"2719","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Development of a Classification Model for Intramammary Infection at Dry-Off Using Indirect Cow-Level Indicators"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-0942-0362","authenticated-orcid":false,"given":"Luca","family":"Barin","sequence":"first","affiliation":[{"name":"Department of Animal Medicine, Production and Health, University of Padua, Viale dell\u2019Universit\u00e0 16, 35020 Legnaro, 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Resist. Infect. Control"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e316","DOI":"10.1016\/S2542-5196(17)30141-9","article-title":"Restricting the Use of Antibiotics in Food-Producing Animals and Its Associations with Antibiotic Resistance in Food-Producing Animals and Human Beings: A Systematic Review and Meta-Analysis","volume":"1","author":"Tang","year":"2017","journal-title":"Lancet Planet. Health"},{"key":"ref_3","first-page":"1350","article-title":"Reducing Antimicrobial Use in Food Animals","volume":"351","author":"Glennon","year":"2017","journal-title":"Science"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"10381","DOI":"10.3168\/jds.2017-13023","article-title":"A 100-Year Review: Mastitis Detection, Management, and Prevention","volume":"100","author":"Ruegg","year":"2017","journal-title":"J. Dairy Sci."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"3150","DOI":"10.3168\/jds.2008-1741","article-title":"Meta-Analysis of Dry Cow Management for Dairy Cattle. Part 2. Cure of Existing Intramammary Infections","volume":"92","author":"Halasa","year":"2009","journal-title":"J. Dairy Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"249","DOI":"10.3168\/jds.S0022-0302(07)72626-7","article-title":"Treatment Practices and Quantification of Antimicrobial Drug Usage in Conventional and Organic Dairy Farms in Wisconsin","volume":"90","author":"Pol","year":"2007","journal-title":"J. Dairy Sci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"7161","DOI":"10.3168\/jds.2021-21455","article-title":"Invited Review: Selective Use of Antimicrobials in Dairy Cattle at Drying-Off","volume":"105","author":"McCubbin","year":"2022","journal-title":"J. Dairy Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"696","DOI":"10.3168\/jds.S0022-0302(69)86632-4","article-title":"Control of Mastitis in the Dairy Herd by Hygiene and Management","volume":"52","author":"Neave","year":"1969","journal-title":"J. Dairy Sci."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"637","DOI":"10.1136\/vr.k2382","article-title":"Pan-European Agreement on Dry Cow Therapy","volume":"182","author":"Bradley","year":"2018","journal-title":"Vet. Rec."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"112","DOI":"10.3168\/jds.S0022-0302(02)74059-9","article-title":"The Effect of Selective Dry Cow Treatment on New Intramammary Infections","volume":"85","author":"Berry","year":"2002","journal-title":"J. Dairy Sci."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3753","DOI":"10.3168\/jds.2015-9963","article-title":"Effect of Different Scenarios for Selective Dry-Cow Therapy on Udder Health, Antimicrobial Usage, and Economics","volume":"99","author":"Scherpenzeel","year":"2016","journal-title":"J. Dairy Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1225","DOI":"10.3168\/jds.S0022-0302(07)71611-9","article-title":"Stochastic Modeling to Determine the Economic Effects of Blanket, Selective, and No Dry Cow Therapy","volume":"90","author":"Huijps","year":"2007","journal-title":"J. Dairy Sci."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Ut, I.D., Berean, D.I., Bogdan, L.M., Ciupe, S., and Gog Bogdan, S. (2025). Selective Dry Cow Therapy in Modern Dairy Management: Balancing Udder Health and Antimicrobial Stewardship. Vet. Sci., 12.","DOI":"10.3390\/vetsci12060580"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"101567","DOI":"10.1016\/j.animal.2025.101567","article-title":"Transition to Selective Dry Cow Therapy for Responsible Antimicrobial Use in Dairy Cattle: A Case Study","volume":"19","author":"Contiero","year":"2025","journal-title":"Animal"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Kabera, F., Roy, J.-P., Afifi, M., Godden, S., Stryhn, H., Sanchez, J., and Dufour, S. (2021). Comparing Blanket vs. Selective Dry Cow Treatment Approaches for Elimination and Prevention of Intramammary Infections during the Dry Period: A Systematic Review and Meta-Analysis. Front. Vet. Sci., 8.","DOI":"10.3389\/fvets.2021.688450"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"7276","DOI":"10.3168\/jds.2019-17438","article-title":"Evaluation of Quarter-Based Selective Dry Cow Therapy Using Petrifilm on-Farm Milk Culture: A Randomized Controlled Trial","volume":"103","author":"Kabera","year":"2020","journal-title":"J. Dairy Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"270","DOI":"10.3168\/jds.2013-7060","article-title":"Evaluation of Selective Dry Cow Treatment Following On-Farm Culture: Risk of Postcalving Intramammary Infection and Clinical Mastitis in the Subsequent Lactation","volume":"97","author":"Cameron","year":"2014","journal-title":"J. Dairy Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"9063","DOI":"10.3168\/jds.2020-19258","article-title":"Randomized Controlled Field Trial Comparing Quarter and Cow Level Selective Dry Cow Treatment Using the California Mastitis Test","volume":"104","author":"Swinkels","year":"2021","journal-title":"J. Dairy Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"760","DOI":"10.3168\/jds.2024-25418","article-title":"Comparison of a Machine Learning Model with a Conventional Rule-Based Selective Dry Cow Therapy Algorithm for Detection of Intramammary Infections","volume":"108","author":"Rowe","year":"2025","journal-title":"J. Dairy Sci."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"11035","DOI":"10.3168\/jds.2021-20504","article-title":"Evaluation of 4 Predictive Algorithms for Intramammary Infection Status in Late-Lactation Cows","volume":"104","author":"Rowe","year":"2021","journal-title":"J. Dairy Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"5652","DOI":"10.3168\/jds.2020-19366","article-title":"Partial Budget Analysis of Culture- and Algorithm-Guided Selective Dry Cow Therapy","volume":"104","author":"Rowe","year":"2021","journal-title":"J. Dairy Sci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"10232","DOI":"10.3168\/jds.2020-20036","article-title":"Detecting Intramammary Infection at the End of Lactation in Dairy Cows","volume":"104","author":"McDougall","year":"2021","journal-title":"J. Dairy Sci."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Guadagnini, M., Gogna, C., Tolasi, C., Tolasi, G., Gnali, G., Freu, G., Masroure, A.J., and Moroni, P. (2023). Approach to Selective Dry Cow Therapy in Early Adopter Italian Dairy Farms: Why Compliance Is so Important. Animals, 13.","DOI":"10.3390\/ani13223485"},{"key":"ref_24","unstructured":"(2026, May 01). NMC Procedures for Collecting Milk Samples. Available online: https:\/\/www.nmconline.org\/wp-content\/uploads\/2016\/09\/Procedures-for-Collecting-Milk-Samples.pdf."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"334","DOI":"10.3168\/jds.S0022-0302(96)76368-3","article-title":"Effects of Freezing on the Viability of Nine Pathogens from Quarters with Subclinical Mastitis","volume":"79","author":"Murdough","year":"1996","journal-title":"J. Dairy Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"301","DOI":"10.2754\/avb200776020301","article-title":"Effects of Freezing Milk Samples on the Recovery of Alimentary Pathogens and Indicator Microorganisms","volume":"76","year":"2007","journal-title":"Acta Vet. Brno"},{"key":"ref_27","unstructured":"(2026, May 01). NMCRC Interpreting Bacteriological Culture Results to Diagnose Bovine Intramammary Infections. Available online: https:\/\/www.nmconline.org\/wp-content\/uploads\/2016\/08\/Interpreting-Bacteriological-Culture-Results.pdf."},{"key":"ref_28","unstructured":"Adkins, P.R.F., Middleton, J.R., Fox, L.K., Pighetti, G., Petersson-Wolfe, C., and National Mastitis Council (U.S.) (2017). Laboratory Handbook on Bovine Mastitis, National Mastitis Council."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"4309","DOI":"10.3168\/jds.2018-15642","article-title":"Evaluation of Test-Day Milk Somatic Cell Count Information to Predict Intramammary Infection with Major Pathogens in Dairy Cattle at Drying Off","volume":"102","author":"Lipkens","year":"2019","journal-title":"J. Dairy Sci."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1017\/S0022029925101234","article-title":"Investigation of Quarter-Selective Dry Cow Therapy Based on Bacteriological Outcomes on Dairy Farms","volume":"92","author":"Beckmann","year":"2025","journal-title":"J. Dairy Res."},{"key":"ref_31","unstructured":"Mein, G.A., Neijenhuis, F., Morgan, W.F., Reinemann, D.J., Hillerton, J.E., Baines, J.R., Rasmussen, M.D., Timms, L., Britt, J.S., and Farnsworth, R. (2001). Evaluation of Bovine Teat Condition in Commercial Dairy Herds: 1. Non-Infectious Factors. Proceedings of the 2nd International Symposium on Mastitis and Milk Quality, Vancouver, BC, Canada, National Mastitis Council."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"105728","DOI":"10.1016\/j.psj.2025.105728","article-title":"Combined Analysis of Multiple Linear Regression and Principal Components for Predicting Performance Indicators in Broiler Chickens under Commercial Conditions","volume":"104","author":"Freitas","year":"2025","journal-title":"Poult. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Moschovas, M., Pavlatos, G., Basdagianni, Z., Manessis, G., and Bossis, I. (2023). A Cross-Sectional Study of Risk Factors Affecting Milk Quality in Dairy Cows. Animals, 13.","DOI":"10.3390\/ani13223470"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Sahar, M.W., Beaver, A., von Keyserlingk, M.A.G., and Weary, D.M. (2020). Predicting Disease in Transition Dairy Cattle Based on Behaviors Measured before Calving. Animals, 10.","DOI":"10.3390\/ani10060928"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Harrell, F.E. (2015). Regression Modeling Strategies: With Applications to Linear Models, Logistic and Ordinal Regression, and Survival Analysis, Springer International Publishing.","DOI":"10.1007\/978-3-319-19425-7"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1186\/1751-0473-3-17","article-title":"Purposeful Selection of Variables in Logistic Regression","volume":"3","author":"Bursac","year":"2008","journal-title":"Source Code Biol. Med."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"3427","DOI":"10.3168\/jds.2020-19378","article-title":"Dynamics of Somatic Cell Count (SCC) and Differential SCC during and Following Intramammary Infections","volume":"104","author":"Kirkeby","year":"2021","journal-title":"J. Dairy Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"430","DOI":"10.1016\/j.rvsc.2011.05.010","article-title":"Relationship between Teat-End Condition, Udder Cleanliness and Bovine Subclinical Mastitis","volume":"93","author":"Faccioli","year":"2012","journal-title":"Res. Vet. Sci."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"577","DOI":"10.3168\/jds.S0022-0302(05)72720-X","article-title":"Short Communication: Association Between Milk Yield at Dry-Off and Probability of Intramammary Infections at Calving","volume":"88","author":"Hogan","year":"2005","journal-title":"J. Dairy Sci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"9224","DOI":"10.3168\/jds.2019-18082","article-title":"Incidence of Milk Leakage after Dry-off in European Dairy Herds, Related Risk Factors, and Its Role in New Intramammary Infections","volume":"103","author":"Holstege","year":"2020","journal-title":"J. Dairy Sci."}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/16\/17\/2719\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T11:56:21Z","timestamp":1788263781000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/16\/17\/2719"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,1]]},"references-count":40,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["ani16172719"],"URL":"https:\/\/doi.org\/10.3390\/ani16172719","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,1]]}}}