# Poultry Mortality Composting and Carcass Management


## Key Takeaways

- Composting poultry mortality is an effective biosecure method for routine disposal, relying on aerobic microbial degradation to produce a soil amendment while reducing pathogen load and odor, provided site planning, legal compliance, process monitoring, and biosecurity are systematically applied.
- Optimal composting requires maintaining internal pile temperatures between 55-65°C for pathogen inactivation and moisture content between 40-60%, with a carbon-to-nitrogen ratio of 25:1 to 40:1 achieved through appropriate bulking agents like sawdust or straw.
- Regulatory compliance is paramount, necessitating verification of local and state environmental regulations, and adherence to specific protocols for reportable diseases (e.g., highly pathogenic avian influenza) which may mandate alternative disposal methods or supplemental disinfection.
- Biosecurity measures are critical, including dedicated equipment, rodent and fly control, leachate management, and quarantining composting zones from active production areas to prevent pathogen translocation.
- For mass mortality events, immediate containment in high-carbon piles is essential, followed by escalation to state or federal animal health authorities for disposal direction, as standard composting may be insufficient or prohibited.
- Process monitoring, including regular temperature, moisture, and oxygen measurements, is crucial for ensuring pathogen inactivation and preventing anaerobic conditions, with deviations requiring corrective actions such as turning or adjusting carbon/moisture levels.

---

Composting is a biologically stable management method for routine poultry mortality when site planning, legal compliance, process monitoring, and biosecurity measures are systematically applied. This approach relies on aerobic microbial degradation of carcass tissues, producing a soil amendment while reducing pathogen load and odor. Proper implementation requires upfront assessment of regulatory constraints, facility layout, carbon source availability, and emergency response protocols.

## At a Glance

| Aspect | Key Consideration |
| --- | --- |
| Site Planning | Locate windrows on impermeable or well-drained surfaces, at least 100 meters from water sources and property lines. Maintain access for equipment. Reference [USDA APHIS Livestock and Poultry Disease](https://www.aphis.usda.gov/livestock-poultry-disease) siting guidance. |
| Legal Checks | Verify local and state environmental regulations, reportable diseases (e.g., highly pathogenic [avian influenza](/knowledge/bacteria/avian-bacteria/avian-influenza-cdc-global-surveillance)) may mandate alternative disposal under [WOAH Terrestrial Animal Health Code](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/) |
| Process Monitoring | Track internal temperature (55,65°C target for pathogen inactivation) and moisture (40,60%). Turn windrows after the primary heating phase. Consult [Merck Veterinary Manual](https://www.merckvetmanual.com/) composting guidelines. |
| Biosecurity | Use dedicated equipment, control rodents and flies, manage leachate, and quarantine composting zones from active production areas. See [The biosecurity of on-farm mortality composting](https://api.elsevier.com/content/abstract/scopus_id/33847078845) (2007). |
| Emergency Response | For mass mortality events, escalate to state or federal animal health authorities. Use high-carbon containment piles, refer to [WOAH Terrestrial Animal Health Code](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/) emergency disposal sections. |

## System Context and Rationale
On-farm composting offers a practical alternative to incineration, rendering, or burial for routine poultry mortality. The process relies on naturally occurring thermophilic bacteria and fungi that metabolize organic nitrogen and carbon from carcasses and bulking agents. Properly managed windrows achieve internal temperatures sufficient to inactivate many common [poultry pathogens](/knowledge/bacteria/avian-bacteria/major-pathogens-associated-poultry-bacterial-viral-parasitic-threats), including [Newcastle disease virus](/knowledge/viruses/avian-viruses/newcastle-disease-virus) and [infectious bursal disease virus](/knowledge/viruses/avian-viruses/infectious-bursal-disease-virus), as documented in [PubMed record 41634863](https://pubmed.ncbi.nlm.nih.gov/41634863/). The [FAO Animal Production and Health](https://www.fao.org/animal-production/en/) highlights composting as a low-capital, biosecure option suitable for small to large-scale operations. However, the method requires disciplined process control, deviations in moisture, aeration, or carbon-to-nitrogen ratio can result in anaerobic conditions, odor generation, and incomplete pathogen kill.

## Planning Decisions
### Regulatory Compliance
Before establishing composting sites, operators must consult local environmental and agricultural authorities. Permits may be required for mortality disposal, especially in zones with high water tables or sensitive watersheds. For reportable diseases,such as highly pathogenic [avian influenza](/knowledge/bacteria/avian-bacteria/avian-influenza-cdc-guidelines-poultry-pandemic-preparedness) or Newcastle disease,the [USDA APHIS Livestock and Poultry Disease](https://www.aphis.usda.gov/livestock-poultry-disease) protocols specify that composting may be prohibited or require supplemental disinfection steps. The [WOAH Terrestrial Animal Health Code](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/) similarly advises that national veterinary authorities approve any carcass disposal method during an outbreak. Legal consultation is necessary because regulations vary substantially by jurisdiction.

### Site Selection and Windrow Design
Select a location with good drainage, away from wells, streams, and ventilation intakes of poultry houses. A concrete or compacted clay base minimizes leachate infiltration. Windrow size directly affects oxygen diffusion. The paper [Procedures and equations for sizing of structures and windrows for composting animal mortalities](https://api.elsevier.com/content/abstract/scopus_id/0034313272) (2000) provides sizing equations based on bulk density and oxygen demand. Typical windrows are 1.2 to 1.8 meters high and 2.4 to 3.6 meters wide at the base. Larger dimensions risk oxygen depletion at the core, while smaller piles may not retain sufficient heat. Carbon source selection,such as sawdust, wood shavings, poultry litter, or straw,must achieve a carbon-to-nitrogen ratio of 25:1 to 40:1. The [USDA National Animal Health Monitoring System](https://www.aphis.usda.gov/livestock-poultry-disease/nahms) surveys indicate that operators frequently use spent bedding or locally available materials, but the carbon source must be dry and absorbent to manage moisture.

### Core Management Framework
Standard composting proceeds through a primary heating phase (first 10 to 14 days) and a curing phase (30 to 90 days). Carcasses are placed in a base layer of carbon material at least 30 centimeters deep, then covered with additional carbon to form a cap 45 to 60 centimeters thick. Internal temperature should reach and maintain 55°C for at least three consecutive days to inactivate most viruses and bacteria. Moisture content is critical: below 40 percent halts microbial activity, above 60 percent produces leachate and anaerobic pockets. Turning the windrow after the primary heating phase redistributes mass and re-oxygenates the pile. The [A systematic review of biochar use in animal waste composting](https://api.elsevier.com/content/abstract/scopus_id/85063581635) (2019) notes that biochar as an amendment can improve aeration and nitrogen retention, although data from field poultry trials remain limited. Process monitoring must include temperature, oxygen, and moisture measurement at multiple depths.

## Biosecurity and Emergency Response
Composting can contain and reduce pathogen loads when managed correctly. The review [The biosecurity of on-farm mortality composting](https://api.elsevier.com/content/abstract/scopus_id/33847078845) (2007) concludes that risks of pathogen translocation via leachate, vectors, or wind are low under proper operating protocols. Nevertheless, operators should limit access to composting areas, use dedicated or sanitized equipment, and control rodent and fly populations. During a mass mortality event,caused by disease outbreak, heat stress, or power failure,immediate containment supersedes routine composting. Emergency guidance from the [USDA APHIS Livestock and Poultry Disease](https://www.aphis.usda.gov/livestock-poultry-disease) and [WOAH Terrestrial Animal Health Code](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/) emphasizes isolating carcasses in high-carbon, covered piles to minimize odor and vector attraction, while contacting veterinary authorities for disposal directions. Uncertainty remains about the precise temperature-time requirements for novel or emerging pathogens, professional escalation to a veterinarian or extension specialist is warranted when disease status is unknown. The [PubMed record 36368260](https://pubmed.ncbi.nlm.nih.gov/36368260/) describes factors that affect composting efficacy during disease outbreaks, reinforcing that site-specific adjustments are often necessary.

## Facilities and Environment

Composting poultry mortality requires a dedicated site that minimizes environmental impact and operational hazards. The composting pad should be located on well-drained ground, at least 60 meters from water sources and 150 meters from neighboring residences, consistent with recommendations from the FAO Animal Production and Health division. The pad surface can be compacted soil, clay, or concrete, with a slight slope to direct leachate away from the working area. If concrete or an impermeable liner is used, a leachate collection system must be installed to capture and treat runoff. The USDA APHIS Livestock and Poultry Disease guidelines emphasize that the composting area must be fenced and locked to exclude wildlife and unauthorized personnel, and a separate entrance for delivery vehicles helps prevent cross-contamination.

Windrow dimensions depend on the expected mortality volume. Sizing equations for trapezoidal windrows have been published, with base width, height, and length calculated from the number of carcasses and the desired free air space (Scopus 0034313272). A typical windrow for daily mortality may have a 3 to 4 meter base and 1.5 to 2 meter height, while large emergency piles can be built wider. The pile must be covered with a 30 to 60 centimeter layer of finished compost or sawdust to insulate the core and suppress odors. Moisture content should be maintained at 50 to 65 percent, too little moisture stalls microbial activity, and too much creates anaerobic conditions. The systematic review of biochar use in animal waste composting indicates that adding 5 to 10 percent biochar by volume improves moisture retention and reduces ammonia emissions (Scopus 85063581635). Aeration is passive in static piles but can be enhanced by placing perforated pipes at the base or by scheduled turning with a front-end loader. Turning frequency typically ranges from weekly to monthly depending on temperature decline.

## Nutrition and Water Interaction

Although dead birds do not consume feed or water, the chemical composition of carcasses directly affects composting dynamics. Poultry carcasses are high in nitrogen (approximately 3 to 5 percent dry matter) and moisture (70 to 80 percent). This requires a carbon-to-nitrogen ratio of 25:1 to 30:1 in the bulking agent. Common carbon sources include wood shavings, straw, or leaf litter. If sawdust is used, its particle size should be 2 to 10 millimeters to allow adequate porosity. The Merck Veterinary Manual notes that very fine sawdust can compact and reduce oxygen diffusion. Water must be added when the pile feels dry and crumbly, but no standard volume can be given because evaporation rates vary with wind, temperature, and turning frequency. A simple field test is to squeeze a handful of material: it should feel like a damp sponge and emit only a few drops of water.

## Production-Stage Decisions

The composting procedure must be adapted to the age and size of birds. Chicks and poults require less bulking agent because of their smaller size and higher surface-to-volume ratio, but they decompose rapidly and may achieve lower peak temperatures. Mature broilers and spent hens generate more mass and fat, which can slow decomposition if not mixed thoroughly. For routine mortality, a static pile system that is loaded once per day and turned after two to three weeks is common. For catastrophic events (large numbers from disease outbreaks or power failures), emergency windrows or aerated bins are constructed immediately. The WOAH Terrestrial Animal Health Code advises that dead birds be composted within 24 hours of death to minimize pathogen amplification and vector attraction. Records must include the date, number, and weight of carcasses, carbon source material used, and temperature measurements from at least two locations in the pile core. Temperature should exceed 55 degrees Celsius for at least three consecutive days to indicate active composting, though exact thresholds for pathogen inactivation depend on the target organism and moisture.

## Records and Documentation

A written composting log is a legal requirement in many jurisdictions and a core component of biosecurity plans. Records should include the date of each addition, type and amount of carbon material, estimated carcass weight, pile dimensions, and daily temperature readings from the core and surface. Any deviations from expected temperature curves (for example, failure to reach 55°C within seven days) must be noted and corrective actions recorded. The USDA National Animal Health Monitoring System recommends retaining records for at least three years, or longer if the operation is enrolled in indemnity programs. Temperature probes should be calibrated semiannually and the calibration date recorded.

## Welfare Considerations

Prompt composting of dead birds directly improves flock welfare by removing sources of infection and ammoniacal odors that stress live birds. The presence of decomposing carcasses attracts flies, which can spread diseases such as fowl pox and salmonellosis. Removing mortality within hours reduces this risk. Composting also provides a rapid alternative to incineration during disease emergencies when rendering services may be unavailable. The FAO Animal Production and Health guidelines stress that composting does not involve live animals, but proper timing of removal aligns with animal welfare principles by preventing live birds from pecking at or consuming dead ones.

## Worker and [Food Safety](/knowledge/bacteria/livestock-bacteria/cooking-chicken-bacteria-prevention)

Workers handling carcasses or compost material must wear rubber gloves, waterproof boots, and N95 respirators to protect against dust, ammonia, and opportunistic bacteria such as Clostridium and Staphylococcus. The biosecurity of on-farm mortality composting has been reviewed, showing that proper composting inactivates most poultry pathogens, including Newcastle disease virus and Salmonella, if the pile reaches sufficient temperature and maintains it for the required duration (Scopus 33847078845). However, the compost must be handled carefully during turning and final application because the outer layers may not have reached lethal temperatures. Compost should be cured for at least 30 days after the active phase, and application to pastures or cropland should be timed to avoid runoff into surface waters. Food safety is a concern if compost is used on vegetables consumed raw, the WOAH code recommends a waiting period of 90 days between compost application and harvest. Testing for Salmonella and E. coli is advisable before land application, especially if the compost originated from a mortality event involving clinical disease.

## Failure Patterns

Incomplete composting is the most frequent failure. It occurs when the pile is too wet (above 70 percent moisture), too dry (below 40 percent), or lacks sufficient carbon. Cold weather slows microbial activity, in ambient temperatures below 5°C, the pile core may not reach 55°C even with adequate sizing. PubMed records indicate that oxygen depletion and anaerobic conditions lead to foul odors, including hydrogen sulfide and volatile fatty acids (PubMed 41634863). Other common failures include surface crusting that inhibits oxygen exchange, and rodent or bird predation if the pile is not covered adequately. Fly infestations signal that the outer carcasses are exposed or that the pile temperature is too low. Incomplete decomposition is detected by the presence of recognizable feathers, bones, or tissue after three months. If this occurs, the material must be remixed with fresh carbon and recomposted.

## Practical Monitoring

Daily monitoring should include temperature from the core and two points at two-thirds depth. Temperature probes must be inserted 60 to 90 centimeters into the pile. A rapid drop in temperature after the first week may indicate exhaustion of carbon or the need for turning. Odor monitoring is subjective but essential: a sweet, earthy smell indicates a healthy aerobic process, ammonia or rotten-egg odors signal imbalance. Moisture can be assessed by squeezing and by weighing a sample before and after drying. Farmers should also inspect the pile perimeter for signs of leachate or animal activity. If the pile fails to heat within five days, the operator should probe for anaerobic pockets and consider adding coarse bulking material. Periodic laboratory analysis of compost for pH, nitrogen, and carbon content helps refine recipe proportions for future batches. The updated USDA APHIS guidance recommends that operators share monitoring data with their veterinarian and extension specialist, especially when managing compost from flocks with known disease history.

## Health Observation and Monitoring

Regular observation of composting piles provides early warning of process failure or pathogen survival. Farmers should monitor internal temperature at multiple depths using a long-stem compost thermometer, recording readings at least twice weekly during the active composting phase. The [Merck Veterinary Manual](https://www.merckvetmanual.com/) notes that sustained temperatures above 55°C (131°F) for several days are necessary to inactivate most poultry pathogens, though specific time-temperature requirements vary by organism. Visible indicators of proper composting include steam rising from piles after turning, a brown or dark color, and an earthy smell. Foul odors, ammonia release, or the presence of flies and scavengers signal incomplete decomposition or excessive moisture.

Moisture content should remain between 40 and 60 percent. A simple field test involves squeezing a handful of compost material: if water drips freely, the pile is too wet, if the material crumbles and does not hold shape, it is too dry. Adjustments are made by adding dry carbon sources such as wood shavings or straw when wet, and water when dry. The [FAO Animal Production and Health](https://www.fao.org/animal-production/en/) guidelines emphasize that monitoring must continue until the carcass material is fully degraded, typically 3 to 6 months depending on carcass size and ambient conditions.

## Biosecurity During Composting

On-farm mortality composting can be conducted safely if biosecurity protocols are strictly followed. The [WOAH Terrestrial Animal Health Code](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/) outlines that composting sites should be located away from live poultry housing, feed storage, and water sources. A buffer zone of at least 30 meters is commonly recommended. Access to the composting area must be restricted to essential personnel, and dedicated boots and tools should be used to prevent pathogen transfer.

A 2007 review on [the biosecurity of on-farm mortality composting](https://api.elsevier.com/content/abstract/scopus_id/33847078845) found that properly managed composting reduces but may not eliminate certain pathogens. The risk of pathogen survival is highest at the pile periphery where temperatures are lower. Therefore, an insulating layer of finished compost or straw at least 30 cm thick should cover all carcasses. Runoff from composting piles must be contained to prevent contamination of surface water or groundwater. In regions with high rainfall, roofed structures or proper siting on well-drained soils are advisable.

## Diagnostic and Veterinary Escalation

Composting is not appropriate for all mortality events. When mortality exceeds normal background levels, or when signs of infectious disease are observed (e.g., sudden death, respiratory distress, neurologic signs, or hemorrhage), the farmer should immediately contact a veterinarian. The [USDA APHIS Livestock and Poultry Disease](https://www.aphis.usda.gov/livestock-poultry-disease) website emphasizes that composting of carcasses from a reportable disease outbreak requires prior approval from animal health authorities. In such cases, incineration or rendering may be mandated to ensure complete pathogen destruction.

Diagnostic samples should be collected by the veterinarian before composting begins. The [PubMed record 36368260](https://pubmed.ncbi.nlm.nih.gov/36368260/) discusses composting as a management option for highly pathogenic [avian influenza](/knowledge/bacteria/avian-bacteria/avian-influenza-climate-change-impact-cdc-surveillance-and-global-mapping) (HPAI) outbreaks but notes that strict temperature monitoring and prolonged composting periods are necessary to achieve virus inactivation. Uncertainty remains about the effectiveness of composting for some prion diseases and spore-forming bacteria. Professional veterinary judgment is essential to determine whether composting is appropriate under specific epidemiological circumstances.

## Uncertainty and Research Gaps

Several areas of uncertainty persist in poultry mortality composting. The systematic review of [biochar use in animal waste composting](https://api.elsevier.com/content/abstract/scopus_id/85063581635) indicates that biochar can reduce nitrogen losses and odor, but large-scale studies in mortality composting are lacking. The effectiveness of composting for emerging pathogens, such as novel influenza strains, has not been fully characterized. Length of composting time needed for complete inactivation varies with particle size, moisture, aeration, and ambient temperature. The [PubMed record 36103492](https://pubmed.ncbi.nlm.nih.gov/36103492/) calls for standardized protocols to evaluate pathogen survival in different composting systems.

Furthermore, carbon-to-nitrogen ratio optimization for carcass composting is less studied than for manure composting. [A 2010 review](https://api.elsevier.com/content/abstract/scopus_id/77955374506) highlights that poultry carcasses have high nitrogen content, requiring substantial carbon amendment to achieve the ideal ratio of 25:1 to 30:1. The long-term effect of repeated carcass composting on soil biology and crop quality when the compost is land-applied remains an area needing more research.

## Sustainability Considerations

Composting aligns with sustainability goals by recycling nutrients into soil organic matter, reducing the need for synthetic fertilizers, and avoiding methane emissions associated with landfilling. The [PubMed record 37559891](https://pubmed.ncbi.nlm.nih.gov/37559891/) notes that composting can lower the carbon footprint of poultry production compared to incineration or rendering, provided the compost is used beneficially. However, the [FAO Animal Production and Health](https://www.fao.org/animal-production/en/) cautions that land application of poultry mortality compost must be managed to avoid nutrient runoff, particularly phosphorus, which can lead to eutrophication.

Farmers should consider the compost as a farm resource, not a waste product. Integration with crop nutrient management plans allows for responsible use. The [USDA National Animal Health Monitoring System](https://www.aphis.usda.gov/livestock-poultry-disease/nahms) has reported that many poultry operations now routinely compost mortalities, contributing to circular nutrient cycles.

## Emergency Mortality Response

Mass mortality events from disease outbreaks, heat stress, or natural disasters require rapid, large-scale carcass disposal. Composting can be scaled up using windrow systems as described in a 2000 publication on [procedures and equations for sizing structures and windrows](https://api.elsevier.com/content/abstract/scopus_id/0034313272). The WOAH code recommends that emergency contingency plans include composting as an option, but biosecurity measures must be intensified. Composting of large numbers of carcasses demands extra carbon material, heavy equipment for turning, and extended monitoring. In such events, veterinary oversight is mandatory, and authorities may impose specific protocols.

## Frequently Asked Questions

**Q1: Can I compost diseased birds without veterinary approval?**
No. If you observe signs of a reportable disease, contact your veterinarian and state animal health official before moving any carcasses. Unauthorized composting of suspect material can spread disease.

**Q2: What temperature must the compost pile reach to kill [avian influenza](/knowledge/bacteria/avian-bacteria/avian-influenza-global-surveillance-and-pandemic-preparedness) virus?**
The virus is inactivated at temperatures above 56°C (133°F) when maintained for several days, but exact time varies. Monitoring must confirm that all parts of the pile achieve these temperatures.

**Q3: How long does it take to fully compost a mature broiler breeder?**
Under optimal conditions, complete decomposition takes 4 to 6 months. Larger carcasses require longer. Regular turning and moisture management shorten the process.

**Q4: Can I use the finished compost on vegetable crops?**
Yes, but wait at least 90 days after the pile has cooled to allow further microbial breakdown. Avoid applying directly to edible portions of crops.

**Q5: What do I do if my compost pile smells like ammonia?**
Ammonia odor indicates excessive nitrogen or insufficient carbon. Add more carbon material such as straw, sawdust, or wood chips. Turn the pile to incorporate.

**Q6: Is it safe to compost birds that died from unknown causes?**
Proceed with caution. Assume any mortality may carry pathogens. Follow all biosecurity precautions and monitor temperatures carefully. Consult a veterinarian if deaths exceed normal rates.

**Q7: Can composting be used for other farm animals like pigs or goats?**
Yes, but the same principles apply. Larger carcasses require more carbon, longer composting times, and more frequent turning. Seek specific guidelines for each species.

**Q8: Will composting attract rodents or flies?**
Improperly managed piles can attract pests. Good practice requires adequate carbon cover, proper moisture, and regular turning. Use traps or bait stations around the site if needed.

---

**Educational Veterinary Notice.** This article provides general guidance on poultry mortality composting. Local regulations vary, and specific pathogens may require alternative disposal methods. Always consult a licensed veterinarian for mortality investigations and disposal decisions. For reportable diseases, follow directives from your national animal health authority.

## Related Farming Guides

- [Broiler Chicken Farming Flock Management From Placement To Processing](/knowledge/animal-farming/poultry/broiler-chicken-farming-flock-management-from-placement-to-processing)
- [Layer Chicken Farming Pullet Development Egg Production Nutrition And Flock Health](/knowledge/animal-farming/poultry/layer-chicken-farming-pullet-development-egg-production-nutrition-and-flock-health)
- [Broiler House Ventilation Fundamentals](/knowledge/animal-farming/poultry/broiler-house-ventilation-fundamentals)
- [Poultry Farm Biosecurity Checklist](/knowledge/animal-farming/poultry/poultry-farm-biosecurity-checklist)
- [Poultry Mortality Investigation And Flock Records](/knowledge/animal-farming/poultry/poultry-mortality-investigation-and-flock-records)

## Related Clinical & Scientific Guides

* [Poultry Farm Fencing: Materials, Design, and Predator Exclusion](/knowledge/animal-farming/poultry/poultry-farm-fencing-materials-design-predator-exclusion)
* [Broiler House Wind Speed and Airflow Measurement](/knowledge/animal-farming/poultry/broiler-house-wind-speed-airflow-measurement)
* [Broiler House Heating Systems: Types and Efficiency](/knowledge/animal-farming/poultry/broiler-house-heating-systems-types-efficiency)


## References and Further Reading

- [FAO Animal Production and Health](https://www.fao.org/animal-production/en/)
- [WOAH Terrestrial Animal Health Code](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/)
- [USDA APHIS Livestock and Poultry Disease](https://www.aphis.usda.gov/livestock-poultry-disease)
- [Merck Veterinary Manual](https://www.merckvetmanual.com/)
- [USDA National Animal Health Monitoring System](https://www.aphis.usda.gov/livestock-poultry-disease/nahms)

> This article is educational and is not a substitute for veterinary diagnosis, treatment, public-health guidance, or regulatory reporting.