Let’s Talk About Bird Flu

[The Birb King]

I noticed about a week ago one of my serama roosters had a slightly swollen eye, and now he has some snot around his nose. I also had a serama hen die a few days ago and don't know why. I had to deal with coryza a few months ago, so I put tiagard in the water thinking it might be that again. I don't think it's bird flu but I am a little worried. My chickens don't free range but there are wild mallards that constantly fly right over the run.

 

[Goosebaby]

I noticed about a week ago one of my serama roosters had a slightly swollen eye, and now he has some snot around his nose. I also had a serama hen die a few days ago and don't know why. I had to deal with coryza a few months ago, so I put tiagard in the water thinking it might be that again. I don't think it's bird flu but I am a little worried. My chickens don't free range but there are wild mallards that constantly fly right over the run.

I’m not a vet so this doesn’t mean all that much but what you described sounds like it could be any number of respiratory infections including LPAI and mycoplasma but maybe not HPAI as it has more severe symptoms or none at all besides sudden death, depending on what internal systems it attacks first. The hen that died suddenly could be it but there are so many other things that can also do that.

From Merck

https://www.merckvetmanual.com/poul...d-wild-birds?query=HPAI#Epidemiology_v3343929

“In peracute cases, clinical signs or gross lesions of avian influenza may be lacking before death. In acute cases, however, lesions may include cyanosis and edema of the head, comb, wattle, and snood (turkey); ischemic necrosis of the comb, wattles, or snood; edema and red discoloration of the shanks and feet due to subcutaneous ecchymotic hemorrhages; petechial hemorrhages on visceral organs and in muscles; and blood-tinged oral and nasal discharges. In severely affected birds, greenish diarrhea is common.
Birds that survive peracute AI infection may develop CNS involvement evident as torticollis, opisthotonos, incoordination, paralysis, and drooping wings. Microscopic lesions are highly variable in both location and severity, and they may consist of edema, hemorrhage, and necrosis in parenchymal cells of multiple visceral organs, the skin, and the CNS.”


No illness is good but some are definitely preferable over HPAI and I’m thinking your birds probably have something other than HPAI.

​

 

[The Birb King]

I’m not a vet so this doesn’t mean all that much but what you described sounds like it could be any number of respiratory infections including LPAI and mycoplasma but maybe not HPAI as it has more severe symptoms or none at all besides sudden death, depending on what internal systems it attacks first. The hen that died suddenly could be it but there are so many other things that can also do that.

From Merck

https://www.merckvetmanual.com/poul...d-wild-birds?query=HPAI#Epidemiology_v3343929

“In peracute cases, clinical signs or gross lesions of avian influenza may be lacking before death. In acute cases, however, lesions may include cyanosis and edema of the head, comb, wattle, and snood (turkey); ischemic necrosis of the comb, wattles, or snood; edema and red discoloration of the shanks and feet due to subcutaneous ecchymotic hemorrhages; petechial hemorrhages on visceral organs and in muscles; and blood-tinged oral and nasal discharges. In severely affected birds, greenish diarrhea is common.
Birds that survive peracute AI infection may develop CNS involvement evident as torticollis, opisthotonos, incoordination, paralysis, and drooping wings. Microscopic lesions are highly variable in both location and severity, and they may consist of edema, hemorrhage, and necrosis in parenchymal cells of multiple visceral organs, the skin, and the CNS.”


No illness is good but some are definitely preferable over HPAI and I’m thinking your birds probably have something other than HPAI.

​

Yea I'm thinking it's some kind of respiratory infection. Especially since that rooster was starting toshow symptoms over a week ago he'd probably be dead by now if it was avian flu

 

[No Coop No Problem]

Saw this recently. It's refreshing to encounter common sense

 

[Goosebaby]

Saw this recently. It's refreshing to encounter common sense
View attachment 4058711

That is a good concept in theory but it presents it’s own challenges.

First off there are different strains of avian flu that are circulating and always evolving. Some strains are less deadly than others and some are more infectious than others and it all has to do with how the viruses infect host cells via their glycoproteins. Low Pathogenic Avian Influenza (LPAI) has strains that once exposed to a bird have trained the bird’s immune system to have some immunity to strains of HPAI, so essentially it’s like a live vaccine against the more deadly strains.
However this isn’t a once done blanket immunity. Avian influenza is always evolving, they may have little to no protection from tomorrow’s mutations and acquired immunity isn’t hereditary, one chicken may be protected from from avian flu through inoculation or exposure to just the right benign version, but her descendants won’t inherited that immunity.

As for genetic immunity, that does exist but there’s a big catch, because of biological differences wild ducks have slight immune resistance to HPAI compared to chickens and other species. This makes them a primary reservoir species for LPAI and HPAI, their resistance to it makes them carriers.

Viruses prefer a species with an immune system that can survive them, immune systems that do not have a severe immune response. They can survive and proliferate in a host who tolerates them long enough to do so, such as in some ducks, even better in species like bats who are borderline symbiotic with them.
However chickens, turkeys, etc do not have that genetic quirk that gives ducks that slight immunity, chickens suffer more severe immune responses to HPAI and that is what kills them. Their immune system overreacts and kills the body trying to kill the virus.

Theoretically there probably are chickens out there that can and have survived HPAI, but they didn’t develop a genetic quirk while fighting the virus that they’ll pass on to future generations, more likely they have an insufficient immune response, meaning there’s an underlying health issue with them that inadvertently spared them from HPAI, or it could be birds that do have a genetic mutation that makes it harder for HPAI glycoproteins to bind to their cells or makes their immune system less reactive.

If it’s the latter I agree, there are benefits to breeding, however that isn’t necessarily a win for chickens. That could spell doom for rare breeds and other species like turkeys and pheasants, etc that may not have resistant individuals, but even still that natural immunity will save them from current strains of HPAI which they have resistance to, but not necessarily future strains, it’s evolution.

Most importantly it must be known that they’ll become like the wild ducks, carriers that will infect chickens and other poultry species who don’t have that natural immunity so anyone with a commercial or backyard flock will have to consider that when exposing new birds into a HPAI resistant flock and ensure that any birds they’re selling or exchanging with others that the others know 100% that they’re receiving possible carrier birds that could decimate their own flocks.

 

[No Coop No Problem]

Acquired immunity isn’t hereditary.

I've yet to see any studies on the subject so I wouldn't be so quick to make such a statement. Mammals often pass down immunity to some extent through breast milk as well as through eating the mother's feces as in Koalas

One chicken may be protected from from avian flu through inoculation or exposure to just the right benign version, but her descendants won’t inherited that immunity.

Good immune system genetics are hereditary however

As for genetic immunity, that does exist but there’s a big catch, because of biological differences wild ducks have slight immune resistance to HPAI compared to chickens and other species. ...
However chickens, turkeys, etc do not have that genetic quirk that gives ducks that slight immunity.

I believe that "genetic quirk" is simply healthy genetics as shaped through the process of natural selection

If it's [chickens with immune genetics] I agree, there are benefits to breeding, however that isn’t necessarily a win for chickens. That could spell doom for rare breeds and other species like turkeys and pheasants, etc that may not have resistant individuals.

Natural selection will solve the issue just as it's done for countless billions of years. Even with chickens, they've been traded around the world for the past 10,000 years and their immune systems have done an excellent job so far

Just take a look at the Egyptian Fayoumi for example. Indians traded Sri Lankan junglefowl along the Silk Road that made a journal of thousands of miles to another continent through the heart of many different ancient civilizations, and they did just fine

 

[Skyeknight]

Just take a look at the Egyptian Fayoumi for example. Indians traded Sri Lankan junglefowl along the Silk Road that made a journal of thousands of miles to another continent through the heart of many different ancient civilizations, and they did just fine

My apologies for this derail of the subject. But do you have a source that Sri Lankan junglefowl is in the genetic makeup of the Egyptian Fayoumi or any other chickens that are not from Sri Lanka for that matter? I would love to see a PM with the source that states that.

 

[No Coop No Problem]

My apologies for this derail of the subject. But do you have a source that Sri Lankan junglefowl is in the genetic makeup of the Egyptian Fayoumi or any other chickens that are not from Sri Lanka for that matter? I would love to see a PM with the source that states that.

I believe this is the thread that goes into intensive detail on the subject. Egyptian Fayoumi are the only breed that practice polyandry, just like their Sri Lankan junglefowl ancestors

 

[Goosebaby]

I've yet to see any studies on the subject so I wouldn't be so quick to make such a statement. Mammals often pass down immunity to some extent through breast milk as well as through eating the mother's feces as in Koalas

That is true but let me clarify what I meant because I wasn’t clear. Acquired immunity, as in vaccination or exposure to a less lethal strain isn’t genetically hereditary.

In the case of a mammal a mother can pass on antibodies to her offspring in utero or through milk, however that’s not genetic, future generations won’t inherit a genetic predisposition to resist a pathogen unless that genetic predisposition already exists, hence why a dog still needs to be vaccinated for rabies even if it’s parents were vaccinated.

Now there is epigenetics though and that is actually hereditary, viruses do attach their rna to host species sometimes which could give an individual some resistance theoretically, but a genetic researcher would be a better person to ask about that, definitely not me. As it is though if epigenetics do play a role with that they can’t anticipate new mutations and they seem unreliably random in their protection, hence the same viruses more or less are still being passed around and causing problems.

Good immune system genetics are hereditary however

I believe that "genetic quirk" is simply healthy genetics as shaped through the process of natural selection

Natural selection will solve the issue just as it's done for countless billions of years. Even with chickens, they've been traded around the world for the past 10,000 years and their immune systems have done an excellent job so far

Just take a look at the Egyptian Fayoumi for example. Indians traded Sri Lankan junglefowl along the Silk Road that made a journal of thousands of miles to another continent through the heart of many different ancient civilizations, and

Good immune system genetics are hereditary. I agree 100%. “Good” though is kind of the wrong word, “effective” is probably more appropriate because genetics that makes cells effective at resisting a virus can make it more susceptible to another virus and having a strong immune response isn’t always a good thing, the issue with chickens in general is their immune response to HPAI is too strong and that’s their downfall, very similar to COVID in some of us.

Natural selection and genetic diversity are the definite key to adapting to a world with hpai. Part of the issue with chickens is that most of the factory farms are mass populated with the same few breeds, it’s such a small genetic pool there isn’t much ability to adapt. Mixed backyard flocks may be more at risk from being exposed to bird flu but they have a better chance at adapting because they’re more likely to be mixed breeds and mixes of many different breeds.
As you said chickens have been brought around the world and have thrived because of natural selection and they’ve encountered and survived all sorts of different pathogens thanks to that, the context though here in particular is HPAI which in general chickens and other species are really struggling with.

HPAI and LPAI are basically the same species of virus currently, there are other versions of bird flu out there and have always been but mostly it’s been different flavors of H5N1 circulating lately, which shows how just small changes in it’s own dna have vastly different results, and that’s where the doom or salvation of or avian friends is.
Current HPAI is temporary. Viruses that adapt quickly tend to get milder over time because the virus better adapts to keeping itself alive through natural selection also. If a host dies quickly through an extreme immune response so dies the virus, eventually the milder ones proliferate better.

The problem with current HPAI is it is so nasty among chickens and other species that it has a chance of creating a bottleneck in chickens which is going to reduce genetic variability and their chances of adapting to future mutations. HPAI is also pretty much everywhere now and has many more opportunities to turn into new versions, better and worse. Next year or in a few years it may mutate into a benign version that becomes the next most dominant strain “hopefully” and after that it could get replaced again with something more lethal that chickens and other species have less resilience too once again, it could be a situation where the chickens that were wiped out by current HPAI may have had a genetic predisposition that may have made them resilient to the future lethal strain but because they’re gone the species as a whole is doomed to extinction.
This is obviously a worst possible case scenario that won’t likely happen, I’m just highlighting that genetic diversity is definitely important as you said and so might be other factors like vaccination “in my opinion” to stay ahead of this.

 

[Seaslug]

Goosebaby, I don't know your background, but if you are not in teaching in some way, you have missed your calling. You are very patient.