Bird Flu in Cattle; What is H5N1 Avian Influenza?

Recently, H5N1 Avian Influenza has been discovered in several herds of dairy cattle. This quickly lead to tests around the country for the virus in diary cattle products, of which most were found to still be safe due to the pasteurization process. Recent USDA Food and Safety and Inspection Service tests suggest that as of right now, the beef industry is safe as well, though there are additional tests on-going. What exactly is H5N1 Influenza? How does it affect animals that it infects, and what potential ramifications are there for Dairy and Beef cattle farmers?

H5N1 Avian Influenza is actually one of several variants of bird flu, known as AIVs, all of which belong to the Influenza A Genus.

 AIVs are further classified based on their pathogenicity (ability to harm the host), to chickens. Virus strains are labeled as either a HPAIV (highly pathogenic avian influenza virus) or LPAIV (low pathogenic avian influenza virus.)

The version of Avian Influenza currently being discussed in the news is an HPAIV, so you may see the virus called something along the lines of HPAI H5N1, or HPAIV H5N1.

The H5N1 strain of avian influenza is considered one of the most pathogenic amongst the HPAIV strains. It is currently estimated to have one of the highest mortality rates in chickens.

Bird Flu can in some cases be spread by waterfowl such as ducks, geese, swans, gulls, and more.

Some types of waterfowl may not get sick or show symptoms of the disease at all while still being able to spread and carry it.

Once the sickness hits a flock of domesticated poultry, it can spread very rapidly amongst the flock.

Infected birds typically shed the virus in their saliva, nasal secretions, and feces.

A bird coming into contact with the secretions, or simply a contaminated surface can quickly catch the disease.

HPAIV strains often have extremely high mortality rates amongst poultry, with some of the recent strains having 90-100% mortality rate.

Symptoms in Cows

• A sudden drop in feed intake with concurrent decrease in rumination (chewing the cud).
• Sudden drop in milk production.
• Milk may become thick and yellow – colostrum like.
• Feces may be abnormal from tarry (black tar like consistency), to overly dry.
• Some cows may experience a fever.
• Cows in second lactation or greater are more likely to be affected.
• Most cows appear to recover after receiving some supportive care.

Learn more with this fact sheet from the Iowa Department of Agriculture & Land Stewardship! 

Symptoms in Chickens

• Sudden death without any prior symptoms of illness.
• Lack of energy or appetite.
• A drop in egg production or soft-shelled, misshapen eggs.
• Swelling of the eyelids, comb, wattles, and shanks.
• Purple discoloration of the wattles, comb, and legs.
• Difficulty Breathing.
• Nasal discharge, coughing, sneezing.
• Twisting of the head and neck.
• Stumbling or falling down.
• Diarrhea.

Learn more from the USDA on Avian Influenza symptoms in birds! 

1878: First reported case of bird flu. While originally called Fowl Plague, years later it was identified correctly and renamed to Avian influenza. Discovered by Edoardo Perroncito in Northern Italy.

1996: New strain of HPAI subtype H5N1 discovered in migratory waterfowl in Guangdong province of China. This virus resulted in the death of around 40% of aquatic birds in the area, and the culling of a massive portion of the poultry population of Hong Kong once the disease spread to them.

1997: The first recorded cases of avian influenza in humans as a result of the Hong Kong outbreak in Guangdong. 18 noted human cases with 6 deaths.

2001-2002: H5N1 avian influenza re-emerged in Hong Kong poultry farms, resulting in the death of an additional 2.5 million birds.

2003: One of the largest recorded outbreaks of avian influenza in past history occurred in the United States. In this case, the variation of avian influenza was H5N2, and killed around 51 million birds through the disease itself, and the necessary culling methods required to keep the disease from spreading further. This incident is estimated to have cost the egg and poultry industry more than 3 billion dollars.

2017: A different version of avian influenza, HPAI H7N9 was discovered, and infected at least 700 people in China

2022: Detections of the H5N1 bird flu in small numbers of other mammals was discovered both in the United states, and several other countries. Foxes, seals, cats, dogs, several bobcats, a coyote, raccoons, skunks, and a badger are all examples of different animals discovered with a trace of the virus. Foxes and seals typically had more cases than other non-bird animals.

2022: 67 countries reported having H5N1 avian influenza outbreaks resulting in more than 131 million poultry birds lost due to diseases and culling control methods used to halt the spread.

2023: The outbreaks of the disease from 2022 roll into 2023, continuing to kill poultry in large numbers.

2024: Cases of H5N1 discovered in some goats on a farm where a poultry flock had tested positive.

2024: Also in 2024, the first infections of cows were discovered. Soon after, cow to cow transmissions began being reported, and a single cow to human transmission of the disease has occurred so far.

Jared Clark is a Silveus agent, and a cow-calf beef cattle producer. We asked Jared a few questions to get his take on the bird flu in cows situation as both an agent, and producer.

Question: So Jarod, what work do you currently do or have done with the dairy or beef cattle industries?

Jared: So I do sell DRP and also LRP, as well as a decent amount of PRF, and then personally, I also run a cow-calf beef operation.

Question: So if its found that dairy cattle have this infection, is the milk that they produce still usable, or do they have to do something different with this milk?

Jared: That has been a debated topic! So for one, I know that there has been a lot of stuff put out that with it being heat treated and pasteurized, that it should have no problems.  They have found it in milk that went into stores, but with it being treated its not a problem. Then I have read that any cows that are affected they are throwing out their full milk production.

Question: Do you see this as a big problem that dairy producers will have to face as time goes on, or do you think it will fizzle down in the next couples of months and they won’t have to worry about it any more?

Jared: I will say this, it feels like the hype and news around it has died down a lot, as far as our neck of the woods has gone. As far as looking for it we are still finding articles, but ill say this, it doesn’t feel like the market is reacting to it. Its like everything, what is the news cycle going to run? And if the news cycle continues to run, yeah I think this will be an issue. I personally feel like its going to be pushed under the rug, and its going to be dealt with behind the curtain. All of the state ag departments USDA,  I do think there will be something that goes on that they will have to have procedures in place to deal with this. So I don’t think it will just completely fizzle out without a resolution

Question: are there regulations from the government that your aware of to be mindful of, or any in the works that your aware of?

Jared:  I do know that there are also some specific regulations that vary by region, so I haven’t dug into region by region or state by state regulations outside of the fact of that there are 17 states that have said hey, we are not importing cattle from states where bird flu has been detected.

Question: Last I was aware bird flu is only affecting the dairy industry when it comes to cattle. However, I recently read an article or two that mentioned that they did some tests on ground beef and are doing additional tests. Do you believe this could bleed over to the beef cattle industry?

Jared: It potentially could, I will say I’m not as near as worried about it as in dairy cattle, but it could.

Question: Do the beef cattle have something that kind of sets them apart from the dairy in this kind of regard to keep them from getting infected as easily?

Jared: Well I think your biggest place for beef cattle to be infected is probably in the feed yards in any type of higher confinement area. So for me personally being cow/calf it doesn’t worry me near as much because I run everything out on pasture, which is generally quite a bit cleaner if you will. You get into areas like feed yards where you have higher confinement. That’s probably where if you get an issue that is where you going to see an issue.

Question: How do you see this issue affecting or not affecting the diary and beef industries as a whole if it does anything at all to them?

Jared: I don’t know that its going to, it does not seem so far like its going to have a huge effect on it. Now if our cases continue to grow, right now in reality our cases are fairly low compared to the amount of cattle we have, so until we have widespread infection I just don’t know that its going to have a huge effect on everything. And the dairy producers are incentivized to take precaution measures to keep this out. Especially if their chucking so much milk you know if they get so many cows infected.

Question: Do you think  it would be a lot more of a problem if the virus mutated to be more lethal in cattle?

Jared: Yeah and that’s the thing, so far unlike it does in birds, it doesn’t seem to affect cattle that much. Its kinda like they get a nice little cold for 2 weeks, and with a little bit of help they get over it. So, the biggest deal would be for it to mutate and start killing cattle, which so far has not been the case.

With DRP being on a state or area yield, I think its going to be really hard, the only way to get a claim on it would be for that state yield to be down in the quarter, so your going to have to affect a huge area before that yield comes down.

The chances are pretty slim. If you get a yield because state yields are down because of bird flu its going to be a disaster. -Jared Clark

While chances of getting a claim may currently be low, the USDA and HHS are offering several different incentives to dairy producers for implementing different bio-security features, as well as a potential compensation for loss of milk production. To learn about these initiatives and if your operation qualifies, please take a look at this fact sheet from the U.S. department of Health and Human Services for more precise details.

Interested in learning more about potential problems for your cattle? Take a look at our article on vomitoxin to learn about the mold that produces it, and how ingesting too much can affect your cattle!