Ag News

Dairy cattle must be H5N1 tested to be moved across state lines

by Jennifer Whittaker

Posted on May 03, 2024 at 14:49 PM

Effective April 29, all lactating dairy cattle must test negative for H5N1 avian influenza before being moved across state lines. The USDA issued this federal order on April 24.

The Georgia Milk Producers (GMP) E-News Bulletin issued April 26 did an excellent job of explaining how testing will work in Georgia. GMP explained that milk samples must be collected and tested within seven days prior to moving lactating cows across state lines.

If a producer needs to move lactating dairy cattle out of state, they should contact the Georgia Department of Agriculture Animal Health team at 404-656-3667 or 

USDA's order states that all samples are to be collected by a licensed veterinarian or someone who has been approved by the appropriate state health official. Dairy producers are encouraged to contact Georgia Milk Producers Executive Director Bryce Trotter at 229-221-3906 or GDA at the above number if they do not have a veterinarian who can  pull samples. Milk samples should be collected from individual cows with each quarter of the udder sampled and combined. A minimum of 5 mL up to 10 mL should be collected from each cow.

The USDA requires that tests must be conducted by a National Animals Health Laboratories Network (NALHN) lab. In Georgia, samples will be shipped to the UGA College of Veterinary Medicine Diagnostic Labs in Tifton or Athens.

Georgia Milk Producers is reporting that the diagnostic labs have told veterinarians farms will need their National Premises ID number to submit samples to the diagnostic lab. Contact GDA 404-656-3667 to get your premises ID if you don’t already know it.

Samples must be collected and negative tests results obtained within 7 days prior to moving lactating dairy cows out of state.

For groups of more than 30 animals moving across state lines, then only 30 animals total must be tested. For groups of less than 30 animals, each animal must be tested. If a cow tests positive for HPAI, you must wait 30 days before retesting that animal.

According to the USDA guidance document for this federal order, APHIS will reimburse for all interstate premovement testing at NAHLN laboratories; therefore, this testing at NAHLN laboratories will be completed at no cost to the producer/submitter. Currently, APHIS is not reimbursing for collecting or shipping samples. Owners of herds in which dairy cattle are cleared for interstate movement are required to provide epidemiological information, including animal movement tracing.

On April 27, the USDA issued a clarification to its April 24 federal order regarding movement of dairy cattle through sale barns and auctions to slaughter.  Per USDA’s clarification, the federal order does not apply to moving a lactating dairy cow from a farm to a sale barn located in the same state. Subsequent interstate movement for a lactating dairy cow from a sale barn directly to a slaughter facility requires only a Certificate of Veterinary Inspection stating that the animal is clinically healthy; no testing is necessary.

The federal order allows lactating dairy cows that are showing no clinical signs of H5N1 to move across state lines directly to slaughter if they are accompanied by a certificate of veterinary inspection or other document approved by the state veterinarians in both the sending and receiving state. 

For now, calves, heifers, and dry cows (pregnant cows not being milked for 60 days prior to calving) are exempt from the requirement of having a negative H5N1 test to be moved across state lines.

USDA APHIS recommends premovement testing of non-lactating cattle as well, but this is not a federal mandate. This testing at NAHLN laboratories will be completed at no cost to the producer. Additional recommendations for testing can be found here. APHIS is also recommending that all animals moved on/off a premises should be isolated for 30 days to prevent the spread of disease.

When it announced the federal mandate for lactating cows to be tested, USDA said any future requirements for other classes of dairy cattle, or expansion beyond dairy cattle, will be based on scientific factors concerning the virus and its evolving risk profile.

USDA is reporting that infected cattle may be asymptomatic (subclinical) or symptomatic (clinical) and the H5N1 virus is predominantly found in milk and mammary tissue regardless of symptoms. Clinical signs may include: a decrease in feed consumption; respiratory signs including clear nasal discharge; and an acute drop in milk production. Additional clinical signs may include abnormal tacky or loose feces, lethargy, dehydration, and fever. Severely affected cattle may have thicker, concentrated, colostrum-like milk or produce no milk at all.

More information about the USDA federal mandate regarding interstate moving of dairy cattle is available at:

USDA Order Restricting Interstate Movement of Dairy Cattle

Guidance Document on USDA Order 

Frequently Asked Questions: USDA Movement Order

Colorado latest state to confirm a case of H5N1 in dairy cattle

On April 25, USDA confirmed the National Veterinary Services Laboratory (NVSL) detected the H5N1 Avian Influenza strain in a dairy herd in northeast Colorado. Colorado has 106 dairies and about 200,000 dairy cows according to the Colorado Department of Agriculture. The virus has now been confirmed in nine states.   

USDA initially confirmed H5N1 detections in dairy herds in the following states: Texas (March 25), Kansas (March 26), Michigan (March 29), Idaho (April 1), New Mexico (April 1), Ohio (April 2), North Carolina (April 9), and South Dakota (April 9). Subsequent detections have been found in other dairy herds in Texas, Michigan, New Mexico, Kansas and Idaho.

USDA believes the initial cases of avian flu in Texas and Kansas dairy cattle originated from wild migratory birds. The initial New Mexico dairies are close to the state line of the Texas panhandle. USDA and/or state officials in at least four states - North Carolina, Michigan, Idaho and Ohio - have said dairy cattle infected with H5N1 in these states can be traced to cows from infected Texas dairy herds being moved to herds in these states. New Mexico officials said cows from Texas were not moved to the infected dairies in its state.

As of the morning of May 2, origination sources for the cases in Colorado nor South Dakota had not been reported nor were there origination details on the subsequent cases at additional dairies in Michigan, Idaho, Texas, New Mexico, and Kansas. Within herds, USDA believes there is cow to cow transmission. One possible way the virus may be spreading within herds of lactating cows is via milking equipment.

FDA/USDA tests prove pasteurized dairy products safe

On April 26, the U.S. Food and Drug Agency announced tests it has done on pasteurized milk taken from store shelves in 38 states show that pasteurization is effective in killing the strain of HPAI (H5N1) found in dairy cows. Although the agency did find dead HPAI viral fragments in about 1 in 5 of the 297 retail samples it tested, to date, the studies of retail milk and dairy products have shown no results that would change its assessment that the U.S. commercial pasteurized milk supply is safe. On May 1, FDA announced a second set of results on 201 of its samples, including cottage cheese and sour cream, that reinforce pasteurization is effective in inactivating HPAI. 

"It is actually expected that RNA will remain in the milk after pasteurization. Heating (pasteurization) will kill the virus but won’t necessarily destroy the genetic material of the virus (RNA),” Dr. Richard Webby, who runs the lab that conducted the testing told AgWeb. “On its own, the RNA isn’t infectious. It is important to reiterate that the presence of RNA does not mean there is live virus. Our data says there is no live virus."

FDA reports “a greater proportion of commercial milk samples showing the presence of inactive (dead) H5N1 fragments came from milk in areas with infected herds.”                                      

To understand why dead fragments of H5N1 could be found in states other than the nine where infected cows have been confirmed, it’s important to understand that commercial milk is trucked from areas of the U.S. where there are more dairies to other parts of the U.S. with fewer dairies. 

FDA says it also tested several samples of retail powdered infant formula as well as powdered milk products marketed as toddler formula. The FDA reports all results of formula testing were H5N1 negative, indicating no detection of viral fragments or virus in powdered formula products.

FDA, CDC and the USDA maintain that consuming pasteurized dairy products regardless of their origin, is the safest way to assure dairy products are safe to consume.

H5N1 has not been found in ground beef

On May 1, USDA’s Food Safety and Inspection Service (FSIS) announced that H5N1 has not been found in any of the samples of ground beef from across the U.S. that the National Veterinary Services Laboratories (NVSL) tested using polymerase chain reaction (PCR). FSIS collected  samples of ground beef from retail stores in each state with dairy herds that tested positive for H5N1 at the time the samples were collected.

To verify the safety of the U.S. meat supply in the context of H5N1, USDA’s FSIS, Animal and Plant Health Inspection Service (APHIS), and Agricultural Research Service (ARS) are working on two separate beef safety studies related to avian influenza in meat from dairy cattle. These three studies are taking place in the interest of scientific inquiry and to reaffirm consumer confidence.

FSIS is collecting muscle samples at FSIS-inspected slaughter facilities of cull dairy cattle that have been condemned for systemic pathologies. The samples will be analyzed by APHIS using PCR to determine presence of H5N1 viral particles. The results will be posted as soon as they become available.

ARS will be conducting a ground beef cooking study using a virus surrogate in ground beef to determine how effective different temperatures are at reducing the virus should it be present in meat. ARS is using the mathematical term logarithmic reduction to measure the number  of the virus substitute eliminated by cooking. Results will be posted as soon as they become available.

Columbia restricts U.S. beef imports

Colombia is restricting fresh/frozen beef and beef products derived from cattle slaughtered in states where H5N1 virus was detected in dairy cattle. The notice was first posted on USDA’s Food Safety and Inspection Service (FSIS) website on April 22.

In a statement issued April 26, the U.S. Meat Export Federation (USMEF) pointed out the restrictions have no scientific basis and Colombia is the only country that has officially restricted imports of U.S. beef.

“Colombia’s attempt to suspend beef imports from specific U.S. states is unworkable and misguided. It has created uncertainty for Colombian importers and their customers as well as their suppliers,  and will greatly disrupt trade,”  the USMEF statement read. “USMEF appreciates the efforts of the U.S. government to address Colombian officials’ concerns, and we are hopeful that this matter can be resolved as soon as possible. USMEF is encouraged that the vast majority of our trading partners are following the science on this matter.  

The U.S. exported about $40 million in beef and beef products to Colombia last year, making the U.S. Colombia’s largest supplier of imported beef, according to the USMEF. Overall, Columbia represents a relatively small percentage of total beef exports, which were valued at nearly $10 billion in 2023, USMEF says.

USDA is posting the latest information about H5N1 in dairy cattle at

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