Gape Worm

No that is not a typo, and I didn't mean to say tape worm. We're talking about gape worm with a G (Syngamus trachea).

Yeah, I had never heard of it either.

I learned about this parasite only after one of our chickens became ill. Dad had noticed her acting 'weird' the day before, but we all thought she was just doing some strange chicken behavior. Chickens can behave strangely at times, and usually it's nothing to be concerned about.

This time, though, the behavior meant something more than a chicken being a chicken. When I let the chickens out of their coop to free range yesterday morning (we lock them up at night to protect them from predators), I noticed one of the hens was already outside of the coop. Now that is extremely unusual, because 99% of the time all of the chickens are back on their roosts by dusk. It's like clockwork. So I knew automatically that something wasn't right.

I went to check her out, and she let me walk up and pick her up with no protest. Another red flag for our chickens, who -- although calm around people -- do not like being caught. She had zero injuries or signs of a predator attack, but she was definitely not doing well. I brought her up to the house to watch her more closely. The symptoms she was exhibiting were some I'd never seen before. First of all, she had the hiccups. (Who knew chickens could even get hiccups?) Secondly, she was breathing heavily, and with every breath she would stick her head way up in the air, inhale as big as possible, and then slowly pull her neck back down to her chest and hang her head. She also had mucous on the tip of her beak.

So off we went to Google. Dad found the culprit first, and I looked up and read what he had found as well. The diagnosis was almost undoubtedly gape worm, and I believe the mucous was an indication of a secondary respiratory infection brought on by the parasites.

So what is gape worm? A nasty, nasty little bugger. The worms set up shop in the birds trachea and feed off their blood. Thinking about it makes me want to gag. Having worms in your trachea must be one of the worst sensations ever. The worms slowly suffocate the bird by blocking off their airway (hence the hiccups, labored breathing, and stretching to try to open the airway). According to what I've read, if the obstruction doesn't kill the birds, a secondary infection usually does.

There were several treatments listed, including fenbendazole (Safeguard), ivermectin, and moxidectin (Cydectin). I had Cydectin on hand, so that was the treatment plan I went with. I wanted to dose her as quickly as possible in the hopes of saving her. I also moved her out of the heat and humidity and onto our air conditioned back porch in the hopes that cool dry air would help her breath. I also offered apple cider vinegar spiked water, but she didn't drink any.

Unfortunately she showed no improvement; instead, she got steadily worse. Dad and I talked it over and decided she most likely wasn't going to make it, and it would be cruel to let her suffocate to death.

So what do we need to know about gape worm?

• Gape worms can be carried and transmitted by some of chickens' favorite snacks, including red worms and slugs. Wild birds can also be carriers.
• You can check for gape worm by examining the throat/trachea of the bird by propping her neck open with something like a pencil. We did not do this (the thought really grosses me out, too), but it would be a good way to differentiate between a respiratory infection or gape worm if there was any doubt. Look up more thorough instructions before trying that, of course.
• Gape worm is apparently most common in young birds and peasants, but can happen in any domesticated fowl. Being on the ground increasing the risk (i.e., free ranging).
•  The only way to completely prevent it, it seems, would be to allow birds zero access to the ground. Since I believe that birds should be allowed to naturally forage, that is not an option.
• Trying to minimize the amount of carriers in the soil or coop area might help. I treated our coop with diatomaceous earth.
• Once a bird is infected, it can expel the eggs of the gape worm through its feces or by breathing. So if you have a symptomatic bird who has gape worm, she has probably deposited the eggs all over the place.
• Based on what I have read, unless gape worm is caught very early the bird is not likely to survive. In my limiting experience and from what I have seen of what it does, I am inclined to believe that. Culling may be the best option unless its caught and treated very early.

I'm no expert, but this is what I have gleaned with my limited internet research.

I hate deworming or giving medication preemptively, but I absolutely believe in treating when necessary. For my goats, I use the FAMANCHA method combined with observing body condition to determine when I need to deworm. I have also been using smart drenching rather than treating on a schedule or treating every animal when one is infested. I also attempt to use natural means to prevent infestations: keeping things clean, feeders up off the ground, keeping water clean, keeping minerals accessible, and bolusing for copper. In the future I hope to be able to use rotational grazing. I will also be breeding for resistance.

But...chickens are a horse of a different color. There is no FAMANCHA method for birds (at least not that I'm aware of). We do work to keep housing clean, put DE under bedding, and allow them room to roam (crowding and confinement increase the spread of parasites). But chickens love to scratch and eat things from the ground, including those insects which are carries for parasites (and parasites themselves, I am sure). This leads me to my next point.

Knowing what I do about gape worm, the horrible way in which it kills, and the fact that our affected hen could have spread it literally all over our entire chicken area, I decided it would be best to deworm all the chickens as a preventative measure. My parents also agreed with this, and I was given the same advice from a friend who also has chickens. Though the dewormer I am using has no milk withdrawal period, it is off-label for chickens. That means no withholding time for eggs has been established or studied.

Which, unfortunately, means that for the next 30+ days, while the chickens are being dosed and the self-imposed withdrawal time to be safe, we will have no eggs to sell to others. We are truly sorry for the inconvenience, but we simply can't risk the health of our entire flock for the sake of being able to sell the eggs. Believe me, it totally sucks to know we'll be throwing out eggs during the middle of the peak laying season. *sigh*

Here are the links to the pages from which I gathered my information:

http://www.backyardchickens.com/t/74676/gapeworm-treatment-and-how-soon-can-you-eat-the-eggs/10 (post #12 here contains the dosage instructions I followed)

http://www.backyardchickens.com/t/87267/gapeworm-what-do-we-do
http://www.backyardchickens.com/t/419463/if-they-have-worms-what-is-the-treatment/10
http://en.wikipedia.org/wiki/Gapeworm
http://poultrykeeper.com/digestive-system-problems/gape-worm-or-syngamus-trachea
http://www.backyardchickens.com/t/602699/worming-chickens/10#post_7931055