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Kristina Smith

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This is a continuation of the post I started last week on the different threats your backyard flock might face. Now let’s talk about chicken illnesses, of which there are plenty, but again thankfully few that our birds actually experienced.


It was around a couple of years ago that our Black Sex-Link hen named Hardcase died suddenly, out of the blue, so naturally that had us concerned. My husband did a semi-exam on her, but he’s not a vet, so there wasn’t an autopsy, and we couldn’t say for certain her cause of death. She did, however have bumps in her mouth, which was strange, but previously we never noticed any odd behavior from her — it was so abrupt, so we started examining the rest of our flock and discovered some white spots on the combs of a few of our birds. We separated the 3 hens from the rest of the flock, not knowing at the time what the issue was, as we began investigating any and all sources.

Maybe a day or two later the separated hens started developing sores around their beaks, and in time we realized the hens with the white spots on their combs had fowl pox (chicken pox for chickens, as I call it; it is not contagious to humans). Fowl pox is usually transmitted by biting mosquitoes or new birds who are carriers of the disease. There are also 2 forms of this disease: Wet pox and dry pox. Wet pox is more deadly than dry pox, because wet pox causes throat and respiratory spots that may develop into large growths, which may make it difficult to eat, drink, and breathe. Initially we were advised to euthanize our flock; that’s the preferred method most people take with birds, because there aren’t a whole lot of poultry vets out there, and illnesses spread so quickly; and if you look at the literature out there, everything says they’ll die, but we were very adamant against doing that.

Sketch of Chicken with Fowl Pox Courtesy of Hannah Smith

These chickens are not our source of food or income; they’re our pets. We’ve named each one, and they all have a story, so we couldn’t just slaughter them. We kept the three hens separated for the requisite time period, prayed for the flock, and in the meanwhile I ordered a vaccine for my remaining birds. Once a bird has fowl pox, if they live, immunity is supposedly life-long. It’s a slow-spreading disease, which is the main reason why I ordered a vaccine; I didn’t want to wait and see what happened to the rest of my birds. I know now that Hardcase must’ve had the wet pox and the other three had the dry pox, and thankfully none of the other birds contracted the illness, because quarantine is a long time away from the flock. I’m happy to report that all 3 hens recovered.


Another disease is coccidiosis, which is a parasitic illness caused by coccidian protozoa, primarily affecting birds when they are younger, which is generally why medicated feed is offered, at least here in Oklahoma. Adult chickens can also get coccidiosis, although they are more resistant due to earlier exposure to infection according to Merck Manual. Signs of infection are decreased growth rate, severe diarrhea, death, and if adults, decreased egg production.

I already mentioned medicated feed for chicks, but if you have an adult bird with coccidiosis, there’s Amprolium (the same treatment in medicated chick starter), which blocks the parasite’s ability to uptake and multiply. Keep brooders and coops clean and dry, make sure waterers are clean, don’t overcrowd the coop, and don’t throw feed and treats on the ground. If you have waterfowl with chickens, make sure the coop is clean and dry and change the water often.

Jango, the hen I thought had gapeworm.


Gapeworm is another issue the birds might come into contact with. When we only had our flock for a couple of years, one of the hens my mother-in-law gave me stretched her neck and coughed from time to time; it had me concerned that she might have gapeworm, however in the end she in fact did not. (Affected chickens stretch their necks out, with their beaks open, gasping for air.) If she ended up having gapeworm, we would have had to order a de-wormer like Ivermectin, although one way to prevent gapeworm is to keep the environment clean and dust-free, tilling the soil in the run at the end of the growing season, which is supposed to reduce residual infection, and to keep up with the worming schedule.

Chickens will stretch their necks out to adjust their crops; I’ve seen my birds adjust theirs after they’ve been eating a lot of food, especially any leftovers I bring out to them, because they eat like the food is running out, and so stuff themselves.


There are mixed reviews for natural de-wormers out there. I’ve used apple cider vinegar and garlic since having chickens, however this past Spring our birds all got the yucky anyway (not gapeworm), and we had to administer Ivermectin after I ordered Wormout gel from Australia-it was going to take several weeks to arrive, and I was impatient to treat my birds. With Ivermectin you just apply the treatment topically, while Wormout gel is added to their water. (I didn’t dose my chickens with the other when it arrived.)

I have read many reviews and spoken to fellow chicken owners who have tried the natural methods as well. Birds, just like any other animal, just like you and me, will still get ill no matter our best laid plans, and sometimes we have to take the stronger stuff. I haven’t administered any more “strong stuff”, because I haven’t seen any indication that I need to. I continue to put ACV in their water once a month; (1 TBSP per 1 gallon each day for 1 week X once a month and sprinkle some garlic in their feed that same week.

Mixed Backyard Flock at Backdoor of House
Our boss hen Fives, the Silver-Laced Wyandotte, close to the front.

Our old boss hen, Fives, had a respiratory illness once, (she was coughing but didn’t have any other symptoms beyond that) and we have no idea what it was, however we separated her from the rest of the flock and once again called my daughter’s father-in-law for an antibiotic. I’m not sure it actually did anything, but eventually she was her old self again as she issued orders and yelled at her subordinates. As always it is recommended to quarantine ill birds from the rest of your flock and to keep the environment clean and dust-free, which can be difficult since these birds love taking dust baths. If you purchase new birds, remember to keep them separate as well for a couple of weeks, to determine if they are healthy or not, before mixing them with the flock.


Avian flu, or more commonly bird flu, is one that is often heard of at least yearly, and when Fives had her mysterious illness we were concerned she might have had it, however no other chicken got sick, she didn’t present with any other symptoms other than coughing, and she recovered. Symptoms include a general decrease in roaming and activity, cyanosis or blueness in the head area, reduction in their appetite, wet eyes, excessive flock huddling and ruffled feathers, fluid in the comb and wattles, decrease in egg production, coughing, legs bleeding underneath the skin, and sudden death. Again the only symptom Fives had was coughing.

You might not completely prevent your birds from getting bird flu, however there are things you can do to protect them: Don’t encourage wild birds from stopping by your yard by feeding them and keep your feeders and waterers clean. Bird flu, just like other bird illnesses, can spread by wild birds. Clean out the coop on a regular basis, pick up feed spillages to avoid attracting wild birds, and have dedicated clothing and footwear you use when handling your birds; make sure not to wear this when anywhere else but around your own birds, especially when around other chickens, because bird flu can live on clothes that have been contaminated by an unhealthy flock for up to two months. Also don’t borrow or use equipment from other people who own chickens, and clean your own equipment with which you used to transport your birds or clean out their coops. And monitor your flock’s behavior, appearance, and appetite.

Avian flu is highly contagious and deadly to birds and humans, although there are vaccines for humans, and failing that, if bird flu is still contracted, antivirals can be administered within 2 days. The only recommendations there are for birds who catch this disease are euthanizing the whole flock, appropriate disposal of the carcasses, and sanitizing the coop.

Sketch of Chickens with Marek's Disease Courtesy of Hannah Smith
This is a sketch of Marek’s Disease.


Another illness in birds is Marek’s disease. Symptoms of this are paralysis of legs, wings, and neck, loss of weight, grey iris or irregular pupil, and vision impairment. It is one of the most common illnesses in small flocks and not treatable once the clinical signs have started, however it is preventable.

Marek’s is caused by a chicken herpes virus, but it won’t make people sick, and once an animal becomes infected, it will remain infected, however not all animals will become sick if infected. Birds become infected by inhaling virus-laden dander, and while the virus is easily killed in it’s pure form, the virus itself can live for years in the dander, meaning that once the disease enters a coop, it can live for a very long time, years, even if birds are all gone. The only way to prevent this disease is to vaccinate day-old chicks before they’re exposed to the virus. Unfortunately not all hatcheries will vaccinate their chicks; the vaccine itself is tricky and has to be used within very specified conditions for it to be effective.

Our trio of Black Ameraucana’s. Shockwave is the one closest to the front.


Vitamin deficiency is something to note here, because it can mimic Marek’s disease. A couple of years ago we think Megatron injured one of his hatchery-mates when he decided he wanted some ‘lovin’; he’s not very coordinated when it comes to mating, and he injured his hatchery-mate (Shockwave), we noticed as she stopped using one of her wings. Eventually she stopped competing for food, I think because she was afraid of getting hurt further by the other birds, so she’d hang back until there was less competition. At the time we didn’t realize what was going on. We knew she was hurt, and we surmised it was due to Megs, but we didn’t realize she was waiting on food, because she was always there when food was being dished out, however over the course of a couple of weeks she started to get weaker, until she was no longer walking.

Sketch of Hen with Vitamin Deficiency Courtesy of Hannah Smith
This is a sketch of our hen Shockwave with vitamin deficiency, but I’ve seen many more photos of birds that look a lot worse.

We thought it was Marek’s due to the paralysis; Hannah was convinced, but I’d remind her that Shockwave was injured originally, so it didn’t make sense. Something was missing, and so I continued researching the matter until I came across vitamin deficiencies that mimic Marek’s. I went to the store and purchased Poly-Vi-Sol infant liquid multivitamin and immediately started administering it to Shockwave. Unfortunately it was too little too late; she died the following day. I felt horrible, because I thought I knew what was going on in my flock and yet here was a bird who died, and I felt it was completely preventable. My point in sharing this story with you is that Newcastles Disease and Marek’s Disease mimic vitmain deficiency in the presentation of paralysis, so it’s vitally important to look at all of the signs. If we had acted sooner we could have saved our hen.


Newcastle Disease is another respiratory illness which causes breathing problems, discharge from nares (nostrils on a chicken), eyes will look murky, egg laying will begin to wane, and wings can become paralyzed as well as birds’ necks becoming twisted.

Sketch of Chickens with Newcastle Disease Courtesy of Hannah Smith

This disease is carried by wild birds, and just like bird flu, it can remain on your clothing and be passed to your flock. Although most older birds will recover, younger birds are at an increased risked from dying from it. Even though there are vaccines available to prevent this disease, there is no treatment for it except antibiotics for secondary infections and supplements. Also like bird flu, Newcastle disease can be spread to people, though it isn’t deadly, producing either no symptoms at all, mild flu-like symptoms, or conjunctivitis or pink eye.

All of the sketches in the post courtesy of Hannah Smith.

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