Dairy Cattle Herd Records: What to Track and How to Use Them
Dairy herd records are the operational data backbone of a commercial dairy farm. They convert daily observations about individual cows into herd-level information that supports culling, breeding, and health management decisions. This article explains which records matter most, how to structure them for practical use, and how to interpret them for action. The content is written for farmers, farm employees, veterinarians, advisers, and farm planners who want to move from collecting data to using it.
Why Herd Records Matter for Dairy Management
Herd records serve two connected purposes. First, they document what has happened to each animal, including calving dates, breeding events, health treatments, and production levels. Second, they allow you to compare your herd's performance against its own history and against external benchmarks. Without records, management decisions rely on memory and impression, which are unreliable when herds exceed a few dozen animals.
The value of structured record keeping has been recognized for decades. Early computerized dairy record systems were designed to handle data from large dairies without disrupting daily routines, and they generated reports that measured reproductive performance against target levels. These systems included data from culled cows, which allowed trends or drops in reproductive performance to be detected more quickly so corrective action could be taken to minimize economic losses. The same principle applies today: records that include all animals, including those that leave the herd, give a more accurate picture than records that only track current cows.
Modern herd management extends beyond simple record keeping. Systems thinking approaches model the relationships among animal groups such as heifers, lactating cows, and dry cows to anticipate milk deliveries over long periods. Feedback loops involving culling, heifer replacement, and pregnancy drive herd dynamics. Understanding these loops helps you see how a change in one area, such as conception rate, affects herd size and milk output months later.
Core Record Categories
A complete herd record system covers three main areas: production, reproduction, and health. Each area answers different management questions, and together they support decisions about which cows to keep, which to breed, and which to treat.
Production Records
Production records track milk yield and composition. The most common source is Dairy Herd Improvement (DHI) testing, which provides standardized measurements of milk, fat, and protein. DHI records also include somatic cell count (SCC), which is a key indicator of udder health.
Production records support several decisions. They identify high-producing cows that deserve continued investment in feed and care. They also identify low producers that may be candidates for culling. When combined with feed cost data, production records allow calculation of revenue minus feed cost per cow, which is a direct measure of economic performance. Grouping cows by production level can improve feed efficiency and economic returns, although the benefits depend on farm conditions and management capacity.
Milk composition data also has diagnostic value. Changes in fat and protein percentages can indicate nutritional problems or metabolic issues. Some advanced systems use mid-infrared spectral data from milk samples to predict additional components, though these predictions have limitations and should not replace direct measurements when precise values are needed.
Reproduction Records
Reproduction records track breeding events and outcomes. Essential data points include calving dates, heat detection dates, insemination dates, pregnancy check results, and calving intervals. From these basic events, you can calculate key performance indicators such as calving-to-first-service interval, days open, and calving-to-calving interval.
Reproductive performance is closely linked to overall management quality and nutrition. After calving, a cow must overcome a series of physiological hurdles before establishing a pregnancy. Selecting timely key performance indicators that monitor specific events in the postpartum and service periods is vital to identify problems and their potential causes. Cumulative sum charts are among the timeliest monitors of heat detection efficiency, insemination outcome, and the relationship between postpartum events and fertility. The point of inflection in these charts indicates when a change took place, allowing you to link management changes to performance shifts.
Estrus expression itself is now measurable with automated monitoring systems. Wearable sensors track activity and rumination changes that accompany heat. Research on large commercial farms has shown that detected estrus contributes significantly to pregnancy success compared with insemination without detected estrus. Estrus duration and intensity also matter. These traits have measurable heritability, which means genetic selection for better heat expression is possible.
Health Records
Health records document disease events, treatments, and outcomes. Common conditions to track include mastitis, lameness, ketosis, milk fever, displaced abomasum, and reproductive tract disease. For each event, record the date, diagnosis, treatment given, and outcome.
Health records serve multiple purposes. They identify cows with recurring problems that may warrant culling. They reveal herd-level patterns, such as a spike in mastitis cases during a particular season or after a management change. They also support genetic selection, since national recording systems in some countries have allowed direct selection for sire families with low incidence of clinical mastitis. In other countries, indirect selection based on somatic cell count has been used. More recently, pooling producer-recorded data from on-farm herd management software has enabled selection for reduced clinical mastitis in the United States and other leading dairy countries.
Health records also support veterinary herd health management. Veterinarians interpret herd health services as advisory work that includes both ad hoc advice and more strategic forms of service. Farmer trust and demand, veterinary competence, time available, and individual commitment all affect how much herd health management actually happens. Good records make these interactions more productive because they give the veterinarian a factual basis for recommendations.
At a Glance: Essential Records and Their Uses
| Record Category | Key Data Points | Primary Management Decisions |
|---|---|---|
| Production | Milk yield, fat %, protein %, somatic cell count, test-day dates | Culling candidates, feed allocation, group assignment, udder health monitoring |
| Reproduction | Calving dates, heat dates, insemination dates, pregnancy results, calving interval | Breeding timing, heat detection efficiency, semen selection, voluntary waiting period adjustments |
| Health | Disease diagnoses, treatment dates and products, recovery outcomes, culling reasons | Treatment protocols, culling decisions, vaccination planning, biosecurity adjustments |
Building a Practical Record System
A record system only works if it fits your daily routine. The best software or paper system is the one you actually use consistently. Start with the minimum data needed for your key decisions, then add detail as the system becomes routine.
Step 1: Define Your Decision Needs
List the decisions you make regularly that involve individual cows or the whole herd. Common examples include which cows to breed, which to treat, which to dry off, and which to cull. For each decision, identify the information that would help you make it better. This becomes your core data list.
Step 2: Choose Your Recording Method
Options range from paper notebooks to specialized dairy software to spreadsheets. Computerized systems offer advantages in data handling and report generation. Early programs demonstrated that computerized records could efficiently handle data from large dairies without disrupting daily routines. Modern systems integrate with milk meters, activity monitors, and other sensors to capture data automatically.
Consider your herd size, staff skills, and budget when choosing a system. A small herd may function well with a well-organized paper system or spreadsheet. Larger herds typically need software to manage the volume of data and generate useful reports.
Step 3: Establish Recording Routines
Decide when and how records will be entered. Daily entry is ideal for health events and breeding activities. Test-day data comes from DHI testing at regular intervals. Assign responsibility for record entry to specific people so it does not get skipped.
Batch entry of data is a practical approach for busy farms. Set aside time each day or several times per week to enter events that occurred since the last entry. Consistency matters more than frequency, as long as no events are missed.
Step 4: Generate and Review Reports
Records have value only when they are reviewed and used. Schedule regular times to examine key reports. Monthly reviews of reproductive performance and health events are common. Quarterly reviews of production trends and culling patterns provide a longer view.
The Dairy Herd Management Program approach demonstrates the value of regular report review. It focuses on specific time intervals and includes data from culled cows, so trends or drops in reproductive performance are detected more quickly. This allows corrective action to be taken before economic losses accumulate.
Using Records for Culling Decisions
Culling is one of the most important and difficult decisions in dairy management. Records provide the factual basis for identifying which cows should leave the herd and when.
Production-Based Culling
Low production is a common reason for culling. Compare each cow's production against herd averages and against her own previous lactations. A cow that consistently produces well below herd average may not be covering her feed and labor costs. Revenue minus feed cost calculations make this comparison explicit by subtracting feed expenses from milk income for each cow.
Production records also help identify cows whose production drops suddenly, which may indicate health problems that require investigation before culling is considered.
Reproduction-Based Culling
Reproductive failure is another major culling reason. Cows that fail to conceive within a reasonable window after calving become economically unviable because they produce milk for fewer days per calving interval. Records of breeding dates and pregnancy checks show which cows are falling behind.
Reproductive performance declines with increasing parity in many herds. This pattern has been observed across different production systems. Cows in later lactations take longer to become pregnant, so culling decisions should account for parity alongside reproductive status.
Health-Based Culling
Recurring health problems justify culling even when current production is acceptable. A cow with repeated mastitis cases, chronic lameness, or other costly conditions may cost more in treatment and lost production than she returns. Health records document these patterns objectively.
Cows that experience lameness in one lactation are less likely to become pregnant and more likely to exit the herd early. This association between previous health events and future performance supports using health history in culling decisions.
Culling Records
Record the reason for every culling event, including whether the cow was sold for dairy purposes, sold for beef, or died on farm. This information reveals patterns in why cows leave your herd. A high proportion of deaths indicates a health or management problem that needs attention. A high proportion of low-production culls may indicate feeding or genetics issues.
Using Records for Breeding Decisions
Breeding decisions involve both timing and genetics. Records support both aspects.
Heat Detection and Insemination Timing
Accurate heat detection is essential for efficient breeding. Records of observed heats and inseminations show how well your heat detection program is working. The interval between calving and first service is a key indicator. If this interval is longer than your target, heat detection may be the problem.
Automated activity monitoring systems provide continuous heat detection data. These systems measure changes in activity and rumination that accompany estrus. Research has shown that detected estrus contributes significantly to pregnancy success compared with insemination without detected estrus. Estrus duration and intensity also affect pregnancy outcomes.
Semen Selection
Records of conception rates by sire help you choose semen that works in your herd. Track pregnancy outcomes by sire to identify bulls with poor fertility in your conditions. This information is especially valuable when using sexed semen, which may have different conception rates than conventional semen.
Voluntary Waiting Period
The voluntary waiting period is the time after calving before you begin breeding a cow. Records of calving dates and subsequent conception show how this period affects reproductive outcomes. Herds with longer voluntary waiting periods may have higher conception rates but longer calving intervals. The optimal period depends on your herd's production, health, and economic situation.
Targeted Reproductive Management
Advanced reproductive management involves identifying cows with different reproductive and performance potential using multiple data sources. These include genomic predictions, behavioral and physiological parameters from sensor technologies, and individual cow and herd performance records. Once subgroups of cows are identified, reproductive management strategies can be tailored to each subgroup.
This approach requires substantial data and analytical capacity. Most herds will benefit first from solid basic records before attempting targeted management. However, the principle of using records to group cows for different management applies at any scale.
Using Records for Health Management
Health records support both individual cow treatment decisions and herd-level prevention programs.
Individual Cow Treatment
When a cow shows signs of illness, her health history informs treatment decisions. A cow with multiple previous mastitis cases may warrant different treatment than a first-case cow. Records of previous treatments also prevent repeated use of products that have not worked.
Herd-Level Pattern Detection
Review health records regularly for patterns. A cluster of mastitis cases in one pen may indicate an environmental problem. An increase in ketosis cases may point to a nutrition issue. Lameness patterns may reveal facility problems such as poor flooring or overcrowding.
The ability to detect patterns depends on consistent recording. Missing records create blind spots that hide problems until they become severe.
Benchmarking
Comparing your herd's health indicators against external benchmarks helps identify areas needing attention. Dairy herd improvement records can be used to develop remote herd assessment tools that benchmark herd status and identify management issues affecting welfare and health. These tools evaluate herds relative to their peers through composite indices and highlight specific areas with opportunities for improvement.
Benchmarking is most useful when you can act on the findings. Choose benchmarks that relate to decisions you can actually make, such as treatment protocols, vaccination programs, or facility changes.
Veterinary Collaboration
Veterinary herd health management works best when records are available for review. Veterinarians can interpret patterns in the data and recommend changes to prevent problems instead of only treating individual cases. Farmer trust and demand for these services affect how much herd health management actually occurs. Good records demonstrate your commitment to proactive management and make veterinary visits more productive.
Records and Measurements: What to Track Over Time
Consistent measurement over time reveals trends that single observations cannot. The following measurements deserve regular attention.
Production Measurements
Track milk yield per cow per day, fat and protein percentages, and somatic cell count. DHI testing provides standardized measurements at regular intervals. Between test days, milk meters in the parlor or automated milking systems provide daily yield data.
Milk composition changes can indicate health and nutritional status. For example, heat stress affects milk yield and composition, with effects varying by lactation stage, parity, and production level. Monitoring these changes helps you adjust cooling and feeding strategies.
Reproduction Measurements
Track calving-to-first-service interval, conception rate, days open, and calving-to-calving interval. These indicators summarize reproductive performance and reveal trends over time.
Reproductive performance varies by season in many herds. Cows breeding during summer or spring in pasture-based systems and spring in housed systems may have reduced reproductive efficiency compared with other seasons. Records by season help you plan breeding management around predictable challenges.
Health Measurements
Track disease incidence rates for major conditions. Calculate cases per 100 cows per year for mastitis, lameness, and other common diseases. These rates allow comparison across time periods and against benchmarks.
Mastitis incidence varies by production system. Housed systems may have higher crude incidence rates than pasture-based systems, though many factors influence these differences. Track your own rates over time to identify trends regardless of external comparisons.
Behavior Measurements
Automated sensors provide continuous behavior data including lying time, rumination, and activity. These measurements have diagnostic value. Pre-calving lying duration is associated with transition cow health and performance. Cows with very low or very high lying times before calving may have higher disease risk.
Behavior data also supports heat detection and stress assessment. Eating time and rumination decline at temperature-humidity index values above 72, with the most pronounced reductions between 72 and 77. These thresholds help you decide when to implement heat abatement measures.
Common Failure Patterns in Record Keeping
Understanding why record systems fail helps you avoid the same problems.
Inconsistent Entry
The most common failure is inconsistent data entry. Records that are complete for some periods and missing for others cannot support reliable analysis. Missing data creates false trends and hides real problems.
Prevention: Assign specific responsibility for record entry. Build entry into daily routines so it becomes habitual. Use batch entry to handle multiple events efficiently.
Recording Without Reviewing
Some farms collect records but never examine them. Data that is never analyzed has no value. The effort of recording is wasted if reports are not generated and reviewed.
Prevention: Schedule regular report reviews. Monthly reviews of reproduction and health data are practical for most herds. Quarterly reviews of production and culling patterns provide a longer view.
Focusing Only on Current Cows
Records that exclude culled cows give a distorted picture of herd performance. If you only track cows that remain in the herd, you miss the failures that led to culling. This creates an artificially positive view of reproductive and health performance.
Prevention: Maintain records for all animals until the end of their productive life. Record culling reasons and include culled cows in performance calculations.
Overcomplicating the System
A record system that requires excessive time or expertise will not be maintained. Complex systems fail when busy staff cannot keep up with entry demands.
Prevention: Start with essential data and add detail gradually. Choose a system that matches your staff skills and available time. Upgrade only when the basic system is working consistently.
Ignoring Data Quality
Records are only useful if they are accurate. Wrong dates, incorrect cow identification, and missing treatment details undermine analysis. Errors compound over time and become difficult to correct.
Prevention: Verify data at entry. Use cow identification systems that minimize errors. Review records periodically for obvious mistakes.
Limitations of Herd Records
Herd records have inherent limitations that affect their interpretation.
Data Quality Depends on Recording Discipline
The accuracy of any analysis depends on the accuracy of the underlying records. Inconsistent or inaccurate recording produces misleading results. This is true for all record systems, from paper to sophisticated software.
Indicators Have Inherent Delays
Many key performance indicators use data from specific cohorts, which adds an inherent delay to when change is indicated. By the time a problem appears in the data, it may have been developing for weeks or months. Cumulative sum charts reduce this delay by detecting changes more quickly, but they require careful setup and interpretation.
Herd-Level Data May Hide Individual Variation
Averages can mask important variation among cows. A herd with an average conception rate may contain groups of cows with very different reproductive performance. Targeted management requires looking beyond herd averages to identify subgroups.
Environmental Factors Confound Comparisons
Herd performance is influenced by many factors beyond management, including climate, feed quality, and disease pressure. Comparing your records to external benchmarks requires accounting for these differences. Herd and environmental factors significantly affect production and fertility traits, so direct comparisons between herds in different conditions may be misleading.
Genetic and Environmental Effects Are Intertwined
Phenotypic trends in production and fertility reflect both genetic changes and management changes. Separating these effects requires sophisticated analysis. For most farm decisions, the combined effect is what matters, but understanding the limitation prevents overinterpreting trends.
Welfare and Safety Context
Herd records support animal welfare and worker safety in several ways.
Welfare Monitoring
Health records document disease incidence, which is a key welfare indicator. High rates of mastitis, lameness, or other painful conditions indicate welfare problems that need correction. Behavior records from automated sensors provide additional welfare information, including lying time and heat stress responses.
The World Organisation for Animal Health addresses animal health and welfare as a core part of its mission. The USDA National Agricultural Library provides resources on animal health and welfare topics. These sources offer guidance on welfare standards and best practices.
Food Safety
Treatment records support food safety by documenting withdrawal periods. Knowing which cows received which treatments and when allows you to keep treated milk and meat out of the food supply. The U.S. Food and Drug Administration provides animal and veterinary resources that include information on drug residues and food safety.
Accurate treatment records are essential for compliance with withdrawal requirements. Missing or inaccurate records can lead to accidental residue violations, which have legal and economic consequences.
Worker Safety
Records of facility maintenance and animal handling can support worker safety. Lameness records may indicate flooring problems that also create slip hazards for workers. Aggressive cow behavior records can identify animals that require special handling precautions.
Professional Escalation Criteria
Some situations require professional assistance beyond what farm records can provide. Escalate to your veterinarian when you observe unexplained patterns in health records, such as rising disease incidence without an obvious cause. Escalate to a nutritionist when production or milk composition trends suggest feed problems. Escalate to an engineer or facility specialist when behavior records suggest housing or ventilation issues.
The Food and Agriculture Organization of the United Nations provides animal production resources that can help you identify when professional input is needed. The USDA Agricultural Research Service conducts animal production and protection research that informs best practices.
Implementing a Record Review Routine
A practical review routine turns records into decisions. The following structure works for most herds.
Monthly Review
Examine reproductive indicators including calving-to-first-service interval, conception rate, and pregnancy rate. Review health events by category and look for unusual clusters. Check somatic cell count trends and identify cows with elevated counts.
Quarterly Review
Examine production trends by lactation number and stage of lactation. Review culling patterns and reasons. Compare current performance against the same period in previous years. Assess whether management changes are having the intended effects.
Annual Review
Evaluate the full year of records for long-term trends. Review genetic progress by comparing production and health traits across years. Assess the economic performance of the herd using revenue minus feed cost calculations. Set targets for the coming year based on realistic assessment of current performance.
Record Review Questions
For each review, ask specific questions. Are reproductive indicators meeting targets? If not, is the problem in heat detection, conception, or both? Are health events increasing in any category? If so, what changed before the increase? Are culling rates and reasons within acceptable ranges? If not, which categories are problematic?
Frequently Asked Questions
What is the minimum set of records a dairy farm should keep?
The minimum set includes calving dates, breeding dates, pregnancy check results, dry-off dates, milk production at each test day, and health events with treatments. These records support the core decisions of breeding, culling, and treatment. Add records for feed purchases and costs if you want to calculate economic indicators like revenue minus feed cost.
How often should herd records be reviewed?
Monthly review of reproductive and health indicators is practical for most herds. Quarterly review of production trends and culling patterns provides a longer view. Annual review supports strategic planning and target setting. The key is consistency, so choose a schedule you can maintain.
What is the difference between DHI records and on-farm records?
DHI records come from standardized testing conducted by Dairy Herd Improvement organizations. They provide consistent measurements of milk yield and composition that support benchmarking and genetic evaluation. On-farm records include daily events such as breeding, treatments, and calving that DHI testing does not capture. Both are needed for complete herd management.
How can records help with culling decisions?
Records identify cows with low production, poor reproduction, or recurring health problems. Revenue minus feed cost calculations show which cows are not covering their costs. Health records reveal patterns of recurring disease that justify culling even when current production is acceptable. Culling reason records show whether your culling patterns match your goals.
What reproductive records are most important for improving fertility?
Calving dates, heat detection dates, insemination dates, and pregnancy check results are the core reproductive records. From these, calculate calving-to-first-service interval, conception rate, and days open. These indicators reveal whether problems are in heat detection, conception, or both. Cumulative sum charts of these indicators detect changes more quickly than monthly averages.
How do automated sensors change record keeping?
Automated sensors capture continuous data on activity, rumination, lying time, and milk production. This data supports heat detection, health monitoring, and stress assessment. Sensor data complements instead of replaces traditional records. You still need to record treatments, breeding decisions, and other management events that sensors cannot capture.
What should I do if my records show a problem I cannot explain?
Start by verifying the data for accuracy. Check for recording errors or missing entries that could create false patterns. If the data is accurate, look for management changes that preceded the problem. If you cannot identify a cause, escalate to your veterinarian or other advisers. Unexplained patterns in health or reproduction records warrant professional investigation.
How long should I keep herd records?
Keep records for the productive life of each animal plus several years for trend analysis. Culling records and treatment histories support future decisions about genetics and management. Some records may be needed for regulatory compliance, so check requirements in your jurisdiction. The USDA National Agricultural Library and other official sources provide guidance on record keeping standards.
Related Farming Guides
- Herd Data Management for Swine Production: Records and Analysis
- Goat Herd Data Management: Records, Analysis, and Decision Support
- Dairy Cattle Farming: Nutrition, Housing, Health Signals, and Herd Management
- Beef Cattle Farming: Forage, Reproduction, Calving, Health Signals, and Herd Management
- Dairy Cow Culling Decisions and Records
References and Further Reading
- FAO Animal Production and Health. Food and Agriculture Organization of the United Nations.
- Animal Health and Welfare. USDA National Agricultural Library.
- Animal and Veterinary Resources. U.S. Food and Drug Administration.
- Animal Health and Welfare. World Organisation for Animal Health.
- Animal Production and Protection. USDA Agricultural Research Service.
- Dairy Herd Management Program.. The Veterinary clinics of North America. Food animal practice, 1987.
- Feedback thinking in dairy farm management: system dynamics modelling for herd dynamics.. Animal : an international journal of animal bioscience, 2023.
- Veterinary herd health management-Experiences and perceptions among Swedish dairy cattle veterinarians.. Journal of dairy science, 2022.
- Early-life management practices and their association with dairy herd longevity, productivity, and profitability.. Journal of dairy science, 2025.
- Genetic Selection for Mastitis Resistance.. The Veterinary clinics of North America. Food animal practice, 2018.
- Development of a Benchmarking Tool for Dairy Herd Management Using Routinely Collected Herd Records.. Animals : an open access journal from MDPI, 2020.
- Herd monitoring to optimise fertility in the dairy cow: making the most of herd records, metabolic profiling and ultrasonography (research into practice).. Animal : an international journal of animal bioscience, 2014.
- Symposium review: Use of multiple biological, management, and performance data for the design of targeted reproductive management strategies for dairy cows.. Journal of dairy science, 2022.
- Feed cost efficiency in robotic milking systems: an analysis of revenue minus feed cost across dairy cow groups in southern Brazil.. 2026.
- Expression of estrus in dairy cows: Phenotyping, genetic variability, and association with productive and reproductive performance.. 2026.
- Real-time milk traits and wearable sensor-derived rumination and feeding behaviors for assessing heat stress effects in dairy cattle.. 2026.
- Reproduction, mastitis, and lameness in housed and pasture-based systems: Associations with parity.. 2026.
- Assessing genotype by feed interactions for milk production traits in dairy cattle.. 2026.
- Influence of herd and environmental factors and phenotypic trends in productive and reproductive traits in dairy farms in Argentina.. 2026.
- Improved transition period management increases milk production of Holstein crossbred cows on smallholder farms in Ethiopia.. 2026.
- Pre-calving lying duration is associated with transition cow health and performance in multiparous dairy cows.. 2026.
- Using dairy herd improvement records and clinical mastitis history to identify subclinical mastitis infections at dry-off. Journal of Dairy Research, 2008.
- Survey of facility and management characteristics of large, Upper Midwest dairy herds clustered by Dairy Herd Improvement records.. Journal of Dairy Science, 2013.
- Changes in first lactation dairy herd improvement records. 1993.
- NEURAL DETECTION OF MASTITIS FROM DAIRY HERD IMPROVEMENT RECORDS. 1999.
- Relationship of Use of Dairy Herd Improvement Records to Herd Performance Measures. 1987.
- Making use of dairy herd improvement records and machine learning to identify best management strategies
- Dairy Herd Improvement Records as Replacement of Technician Breeding Receipt Database for Routine Estimates of Non-Return Rates for Al Bulls in Technician-Devoid Areas.. 1996.
- Short communication: Potential prediction of vitamin B12 concentration based on mid-infrared spectral data using Holstein Dairy Herd Improvement milk samples.. Journal of Dairy Science, 2020.
- A partnership of universities and agri-business for an effective dairy herd management learning experience for undergraduates: The dairy challenge. Journal of Dairy Science, 2003.
- Immediate Effects of Changing Herd Size Upon Milk Production and Other Dairy Herd Improvement Measures of Management. Journal of Dairy Science, 1973.
- Effect of participation by veterinarians in a dairy production medicine continuing education course on management practices and performance of client herds. Journal of the American Veterinary Medical Association, 1996.
This article is educational and is not a substitute for veterinary diagnosis, treatment, public-health guidance, or regulatory reporting.