Table 3.

Principles and elements of AMS that are part of routine veterinary practice on many dairy farms.

		Element of AMS
		AABP, 2022 [66]	Weese et al., 2013 [68]
Core Principle of Judicious Use 1	Examples of Common Practices Related to Antimicrobial Stewardship	Leadership; Drug Expertise; Tracking AMU; Reporting and Action	Responsibility; Reduction; Replacement; Refinement; Review
Prevention	Perform housing assessment Reduce stocking density Modify Gram-negative core antigen vaccine Modify fresh cow environment Change milking order Evaluate and change colostrum harvest protocol Test for failure of passive transfer Evaluate calf and heifer housing Evaluate heat stress control Begin daily herd walk-through Evaluate and revise biosecurity programs Evaluate and revise vaccination programs Review use of shared versus individual needles	ACTION “Review the disease prevention programs such as vaccination, nutrition, and environmental management programs for specific disease conditions to assure optimal husbandry.”	REDUCTION “…requires consideration of the entire spectrum of possible reduction approaches, which also include genetic selection for disease resistance, use of vaccines…, identifying modifiable risk factors and of course, measuring current practice.”
Diagnosis	Begin monthly SCC testing Use CMT at dry off to identify infected quarters Use SCC as part of clinical mastitis treatment protocol Use SCC as part of selective dry cow therapy program Review disease definitions Use on-farm culture to direct clinical mastitis treatment protocols Begin calf health scoring Recording severity score for clinical mastitis Begin fore-stripping (detection of clinical mastitis)	ACTION “Review diagnosis/treatment protocols developed for different disease syndromes.”	REFINEMENT “… improved culture-based diagnostic tests are allowing selective treatment of dairy cattle with purulent vaginal discharge or clinical mastitis, and improved use of SCC data is guiding selective dry cow treatment of dairy cattle, each decreasing amu.”
Drug Selection and Management	Use “watchful waiting” for some non-severe mastitis Evaluate selective Dry cow therapy Evaluate use of internal teat sealants Develop drug inventory control program Requires 2 signatures for culling cows Change protocol for cows to leave hospital/sell milk	DRUG EXPERTISE “Bovine practitioners should provide AMU protocols and treatment guidelines specific for each operation as described in the AABP Guideline” “Establishing and maintaining the veterinarian-client-patient relationship in bovine practice” and “Drug use guidelines for bovine practice.”	REFINE and REPLACEMENT “Replacement of the use of antimicrobials with alternative, nonantimicrobial measures, wherever possible and appropriate, is another critical AMS tenet”
Treatment Protocols	Plan a selective dry cow therapy program Review (change) routine fresh cow treatments Review/revise existing treatment protocols Reduce use of extralabel treatments Review reasons for using antibiotics Review evidence for duration of antibiotic therapy Weigh cattle before dosing injectable antibiotics Review or change criteria for use of antibiotics Review or change antibiotics used for treatment Compare cost of treatment protocols Read labels of all drugs on farm Identify compliance gaps for treatment protocols Schedule quarterly review of treatment protocols Schedule training time of vet with animal health managers	LEADERSHIP “Am I committed to complete the cycle of disease management by following the judicious use of antimicrobial drugs with reevaluation of their need?” “Have I followed the legal requirements for using antimicrobial drugs by selecting approved products when available or choosing legally acceptable extra-label use?”	REFINEMENT “Use all antimicrobial agents, … only after careful review and reasonable justification.” “Use narrow-spectrum in preference to broad-spectrum antimicrobials whenever appropriate.” “Minimize therapeutic exposure to antimicrobials by treating for only as long as needed to meet the therapeutic objective.”
Monitoring	Perform residue tests on milk of fresh cows Evaluate transition cow health Change disease recording system Review health records to estimate disease rates Review calf health records Conduct quality assurance review of on-farm culture results Evaluate outcomes of mastitis treatment program Review cost of drugs Review disease rates in calves/heifers Determine death and culling rates for animals Benchmark AMU	TRACKING and REPORTING “Bovine practitioners should periodically review treatment records, drugs present on the farm in relation to treatment protocols, and on-farm antimicrobial drug dispensing and usage.” “Bovine practitioners should support efforts to report AMU across farms in order to benchmark and compare usage...”	REVIEW “Review includes the measurement of progress toward each objective. Information on the use of antimicrobials can be obtained from both quantitative and qualitative assessments.”
Leadership	Assign fresh cow manager Provide training for on-farm culture program Change personnel making treatment decision Limit access to antibiotics Have veterinarian reassess/review current VFD Begin routine training program for employees	LEADERSHIP “It includes accepting responsibility and accountability for antimicrobial prescribing, dispensing, and administration. This commitment also includes identifying leaders within the practice and client operations to share in antimicrobial stewardship.”	RESPONSIBILITY “There are many enabling mechanisms to ensure that a collaborative and participatory team approach is taken with effective communication with all stakeholders.”

NOTES: ¹ adapted from [68].