Various What Are 840 Tags for Dairy Cows?
By Various
Last reviewed: December 2025
840 tags are official USDA-approved electronic identification ear tags that begin with the 840 country code (United States) and contain a unique 12-digit...
The 840 tag system represents the cornerstone of U.S. animal disease traceability infrastructure. The "840" prefix is the international country code for the United States, followed by a unique 12-digit number assigned to one animal for its entire life.
These tags are manufactured under strict USDA oversight by approved tag manufacturers and distributed through approved channels including veterinarians, breed associations, and authorized tag suppliers. Each tag is registered in the USDA's Animal Health Emergency Management System (AHEMS) database.
For dairy operations, 840 tags became increasingly important with the 2013 ADT final rule, which requires official identification for sexually intact cattle 18 months and older moving interstate. The 2024 updates responding to HPAI concerns have accelerated adoption requirements.
The tags serve dual purposes: regulatory compliance and operational efficiency. While meeting federal requirements, they also integrate with on-farm systems for automated identification at milking, feeding, and handling points.
Key distinctions from management tags: 840 tags are "official" and recorded in federal databases, while management RFID tags are "non-official" for on-farm use only. Many dairies use both—840 tags for compliance and management tags for internal systems.
Key Features
- Official USDA Approval: Manufactured and distributed under USDA oversight with quality standards
- Unique Lifetime Number: Each 15-digit number (840 + 12 digits) assigned to one animal permanently
- Federal Database Registration: Numbers recorded in USDA AHEMS for disease traceback capability
- Tamper-Evident Design: Tags show clear evidence if removal is attempted
- ISO Compliance: Meets ISO 11784/11785 standards for international compatibility
Advanced Features
- Visual-Electronic Combo: Tags display readable numbers while containing RFID chips
- Breed Registry Integration: Can serve as official ID for breed association registration
- State Database Links: Many states link 840 numbers to state-level animal health databases
Ideal For
Farm Types: All dairy operations that sell or move cattle across state lines
Competitive Advantages
What sets What Are 840 Tags for Dairy Cows? apart from alternatives:
- Legal compliance for interstate cattle movement
- Enables rapid disease traceback within 48 hours vs. weeks with visual-only ID
- Supports export market access requiring traceability documentation
- Reduces liability exposure during disease outbreaks
- May qualify for insurance or premium market advantages
Pricing Information
Here is the pricing information for What Are 840 Tags for Dairy Cows?:
$2.50-$4.50 per tag depending on style and quantity; some states offer subsidies
Pricing Model: Per-tag purchase with registration included
Prices may include matching visual tags; check for state cost-share programs
ROI & Value Proposition
Understanding the return on investment for What Are 840 Tags for Dairy Cows?:
Key Benefits:
- Automated estrus detection improving conception rates by 8-15% and reducing days open by 12-18 days
- Early disease detection reducing veterinary costs by $125-200 per cow annually
- Automated sorting and identification reducing labor time by 2.5-4 hours daily
- Improved breeding efficiency increasing pregnancy rates from 68% to 78% average
- Real-time health monitoring preventing metabolic disorders, saving $180-350 per case avoided
- Enhanced milk production tracking enabling precision nutrition adjustments worth $85-140 per cow
- Reduced culling rates by 12-18% through early intervention capabilities
- Improved animal welfare compliance and audit trail documentation
Implementation & Setup
How to implement What Are 840 Tags for Dairy Cows? on your dairy operation:
Implementation Timeline: Order to delivery: 1-4 weeks; application: 1-2 minutes per animal
Training & Support
Training and support options available for What Are 840 Tags for Dairy Cows?:
Support Channels:
Buying Considerations
Important factors to consider when evaluating What Are 840 Tags for Dairy Cows?:
- ISO Compliance and Frequency: Ensure 134.2 kHz HDX tags meeting ISO 11784/11785 standards for universal compatibility with readers and government traceability requirements
- Sensor Integration Level: Choose between basic RFID ($8-12 each) versus multi-sensor tags ($45-85 each) based on management intensity and ROI requirements
- Reading Range and Reliability: Verify 12-18 inch reliable read range for parlor applications, 95%+ read rates in various weather conditions and tag orientations
- Battery Life and Durability: Smart tags should provide 3-5 year battery life with IP67 waterproof rating, withstanding temperature ranges from -20°F to 140°F
- Software Integration Compatibility: Confirm seamless integration with existing herd management software like DairyComp, PCDART, or farm-specific ERP systems
Evaluation Questions
Key questions to consider when evaluating What Are 840 Tags for Dairy Cows?:
- Is the supplier USDA-approved for official tag distribution?
- What is included in the tag package (applicator, matching visual tags)?
- How are tags registered with USDA—automatic or producer responsibility?
- What is the turnaround time from order to delivery?
- Does the tag style work with our existing RFID readers?
Common Mistakes to Avoid
Avoid these common mistakes when implementing What Are 840 Tags for Dairy Cows?:
- Purchasing non-ISO compliant tags to save initial costs
- Installing readers without proper antenna positioning and power calibration
- Failing to establish backup identification systems
- Inadequate staff training on system operation and maintenance
Market Overview
Market Size: $1.8 billion globally in 2024, projected to reach $2.9 billion by 2029
Industry Trends: Integration with farm management software increasing 35% annually,Shift from basic ID to multi-sensor tags combining activity, rumination, and temperature,Cloud-based analytics platforms becoming standard requirement,ISO 11784/11785 HDX compliance driving tag standardization,Real-time health monitoring reducing veterinary costs by 15-25%,Precision breeding applications increasing tag ROI by $85-120 per cow annually