Chicken Necropsies

Over the years I’ve seen many sick chickens. You can divide the ailments into respiratory and other. Respiratory disease can spread quickly through your flock. It can be lethal.  You’ll find a lot of erroneous information online about how to determine which pathogen has caused the outbreak; there is no way of telling without expensive lab tests. I know, because I’ve gone that route. Unless you are a professional farmer, it doesn’t make much difference to know what germs are causing your hens to wheeze and go listless. The treatment is the same. Antibiotics can often stem the tide, as I detailed here.

That other category covers everything from cancer, to fatty liver disease, to internal laying. Once again, it’s sheer guesswork to try to deduce the underlying cause of your hen’s symptoms. Once again, almost everything you read online is wrong. A chicken has only so many ways of looking ill, and that penguin stance, the listlessness, the dark comb, can be caused by any number of very different ailments.

Sometimes those symptoms don’t point to a lethal disease. Sometimes a chicken simply needs to get their internal systems moving. Maybe her mineral balance is out of whack. Maybe an egg is taking too long to move along the repro tract. Maybe her digestion has stalled. In those cases, my Spa Treatment will put things to right. You’ll still only be guessing about the root cause, but at least your hen will get some relief. If the Spa Treatment doesn’t work, and your chicken dies, it’s still all guesswork as to the cause unless you do a necropsy.

Some states allow you to send a dead chicken to their labs to be examined, but this service is meant for professional farmers. If everyone with backyard chickens sent their deceased birds in, it would bankrupt the programs. In any event, my state doesn’t offer this option. My own vet doesn’t do necropsies, either. In the past, if I wanted to know why a chicken died, I’d have to pay to ship it out of state. It was prohibitively expensive. I was frustrated with not knowing what my chickens died of. Fortunately, in January of 2010, I was able to attend a necropsy workshop at a poultry show, where I learned how to do this procedure myself. Because it wasn’t prudent to bring diseased birds onto the premises, we practiced on healthy cockerels. So, the workshop taught me the basics, but after doing my first necropsy on a hen from my own flock, it was obvious that a healthy rooster is nothing like an aged laying hen.

I looked for necropsy tutorials. Cornell Veterinary School has put a 4-hour video online. I watched that. State extension services have basic information online, like this fact sheet from Ohio State. I found papers about specific diseases, like this one on kidney damage in commercial layers. I looked through my collection of poultry books. The most useful illustrations were found in the older books, when farmers had small flocks and did the necropsies themselves.


All of this research was helpful, but what I found inside of my old chickens didn’t match the tidy illustrations from the manuals. I contacted a vet in Michigan who does necropsies with the 4-H club kids. I contacted an avian vet in England who is experienced with older backyard birds. I’ve been learning a lot. I’ve done thirteen necropsies. Each time I learn something new. Each time, before I do the necropsy, I think that I have a good sense of what was wrong with the hen. Each time I was wrong. Two chickens, the same age, breed and care, died within a month of each other. They both exhibited the same symptoms. But, what I found inside was not at all the same.

What I can tell you is that by the time a chicken dies, her internal organs are a mess. I’ve seen ovarian cancer, tumors and blocked guts. I’ve seen masses of solidified eggs in the body cavity, infected fluid, and a heart that looked like jelly. It is astounding what a diseased chicken can live with before she shows signs of illness. I’ve come to believe that by the time I see her standing hunched and miserable, that things have been going wrong inside of her for a long time. This is why, if a hen is not eating on her own, that I don’t feed her with a syringe, or baby her with gruel. Or, If she has fluid in the body cavity, I know that there’s an underlying disease causing it and I’m not going to drain her and keep her around for a few more months. I’ve come to know that when a hen can’t eat, that she is suffering. If she is listless in a corner, then she is suffering. I’ve come to believe in the kindness of euthanizing.

Doing the necropsies has taught me more than I’d ever hope to learn from a book or a video. Doing them has certainly taught me that most of the amateur diagnoses out there (for example, “she’s egg bound”) are just plain wrong. This doesn’t mean that you, too, have to do necropsies. Knowing the cause doesn’t change the outcome. (The only exceptions are the increasing number of hens dying of fatty liver disease because  of overfeeding scratch corn, and the hens dying of kidney disease due to overfeeding of meal worms. Read about feeding here.) However, the knowledge that I gain from the necropsies makes me a better chicken keeper. Telling you about what I find in the necropsies helps everyone.

If you do home necropsies, have taken a necropsy workshop, or found a good source of information, let me know. There’s much more to learn.


    • Just getting started looking at blogs and THANK-YOU for this posting. I love my girls. And I have a great vet who is the bird guy to go to & was kind enough to necropsy one of my girls (for free b/c she was a patient) and found ovarian cancer. The article gave me a lot to think about. Thanks. Please share more of your findings. I hate not knowing and wondering. And I will try to follow.

  1. This is all very interesting Terry – I’ve been mucking around with my girls, most of whom haven’t laid properly since the heat wave last summer. So I’m coming to the sad conclusion that it’s time to cull most of them – I appreciate how you are able to keep your older ladies in retirement, but I don’t have the room to add new birds without “making space” first. But I’d like to know what’s going on that’s keeping them from laying, so necropsy is the way to go. Thanks for the information.

  2. I’ll vouch for this. I’m fortunate enough to live near Terry, and even more fortunate that she was willing to do a necroscopy on one of my hens, who had been healthy and at the top of the pecking order before she became unexpectedly poorly and died.

    I scampered over when Terry agreed, and got a report later that my beautiful bully of a hen had pushed all the other birds out of the way when the scraps were tossed in their run and had apparently eaten enough chickpeas to pack her gizzard tightly full. So full that nothing else could get through.

    I learned a couple of things about how and what kind of scraps to give the birds, and how they act and how they can push each other around. My daughter (who raises, cares for and feeds/waters the hens) became a better keeper of chickens, thanks to having someone help us understand what had caused the hen to die. And we watch the birds with new eyes now, seeing how they treat each other.

  3. Very useful, Terry. Thanks to Ken too. I have a couple bullies I’d better watch out for.

  4. Thank you for this information Terry. I’m not sure I could do a necropsey on a beloved hen but then I never thought I would fix a hen with a prolapse. It is amazing what you find yourself doing when you care about your animals, so perhaps one day, if the need arises, I will learn enough and be up to the task.

  5. Terry, please help me understand what’s up with my hen’s poo. I’ve been on vacation for a week and when I got back I noticed maggots in some poo. What would you say is going on? Thank you,

  6. I feel like this is true of all birds. Pet birds or wild birds.

  7. Would it be possible in the future to collaborate photos of necropsies in an effort to share what has been found?

    • I haven’t put the photos up because some people can’t handle looking at them. Perhaps I can do a link to the collection.

  8. Well said. I do want everyone to know that California is unique in that we have UC Davis, a HUGE veterinarian school. They encourage back yard flock owners to send in their deceased hens for necropsy. It give the students hens to practice on and it gives the state valuable information into the health of birds in the state. It’s free to back yard flock owners and cost about $200 for commercial farmers. And you’ll receive a full necropsy report. They even give you their FedEx shipping number so you can take advantage of their discount. It cost me $13 to overnight my bird to them.

    If you live in CA, I encourage you to visit their website and print off the forms. Read what is required to send in a bird so you can have all the necessary stuff on hand so you are not scrambling at the last minute.

    • Amy, I was wondering why California offered this. I’m surprised with the state’s budget issues that it’s still available.

  9. This is from their home page: The California Animal Health and Food Safety (CAHFS) Laboratory System is the backbone of California’s warning system that helps to protect the health of California’s livestock and poultry. CAHFS serves the people of California by safeguarding the public health with rapid and reliable diagnoses for animal diseases affecting humans. CAHFS operates in partnership with the CDFA, UC Davis, California, veterinarians, and livestock and poultry producers.

    CA is a HUGE agricultural state. No surprise there. They spend quite a bit watching for all kinds of pests and diseases that could affect livestock, the fruit, nut and wine growing industries, etc. This stuff doesn’t usually make the national news but you’d be amazed at how often a shipping container tests positive for a pest and has to be fumigated or fully destroyed. We are constantly being fogged for West Nile Virus. They work tirelessly to keep Fruit Flies out of the state. They have good success flooding an area with sterile flies to eliminate that pest. Budgets might be tight but keeping the state pest free is an area that tends to be well funded year after year.

  10. Fortunately my state (Mississippi) does necropsies for backyard flocks ($50). I am still losing my pullets, so sent this last girl to the state lab. I learned a lot just from the process – I was able to take her to the Health Department yesterday, who had a courier take her to the state lab, who then sent her to the poultry lab early this morning ($9). I already have preliminary findings – nothing obvious other than severe dehydration and emaciation. One of her ovaries looks strange. Waiting for cultures – the pathologist’s best guess in Fowl Cholera.

  11. can you tell if a bird had mareks by doing this yourself? I just had a pullet of 5 months die, started with a leg issue, but vet didn’t seem to think it was mareks but wasn’t positive.