I am pleased I was able to help put your mind at rest a little. I don't personally worry about shed intestinal lining and it hasn't resulted in any problems with my birds on the occasions that I have seen it, but I did read on one post here on BYC about shed intestinal lining, when I was looking for images for it (Kathy beat me to posting some), that it can be caused by capillary worms. I don't know if that is correct or not, but I have not experienced problems with capillary worms in my flock and I haven't wormed them in the past 3 years, so I suspect the "CAN" part of that statement might be a bit like saying you can get run over crossing the road.....ie It's a low risk possibility.
As I suggested in my first post on this thread, the thing to do might be to get a faecal sample analysed for worm eggs.
You have to remember that, as outdoor animals, chickens will most likely have worms so don't assume that you have to worm if you get a positive result. There is a balance with all parasites and a healthy chickens should be able to tolerate a low worm burden and it is probably normal for it to do so. However, sometimes for various reasons, the balance is upset and the parasite infestation becomes too great and the chicken starts to show signs of illness and failing to thrive. In my opinion, that is the time to worm them or if you are seeing worms regularly in their poop. I also check the intestines of cockerels that I process or any other bird that dies (I have Marek's disease in my flock), to give me an idea of the worm burden level. I have never found more than one or two so far.
As regards the "gaping" I think many people see this behaviour and assume it is gape worm because of the name. It is more commonly associated with respiratory infection or crop readjustment than gape worm in my opinion. I've certainly seen my chickens do it and again, I have not found gapeworm but I do have a chronic respiratory infection which circulates my flock every once in a while. Respiratory infections are very common in chickens, so again, this is a more likely cause. It also may be that chickens yawn too.... I know horses, dogs and cats do as well as humans and probably many other creatures, so why not chickens
I do not specifically know why chickens shed intestinal lining but I think it may be to do with their system using grit which will have an abrasive effect on their gut even though it is mostly fine particles that pass out of the gizzard and perhaps the intestine is constantly, if very slowly regenerated as a result of this abrasion and the old remnants shed. This is just a guess based on what I know of their digestive system.... I'll be interested to read Kathy's response to that question because I'm pretty confident that if she doesn't already know, she will find the correct answer for us.
I think the problem with vets is that they usually have little or no experience of chickens. As a business. it doesn't really pay to turn patients/customers away. The honest ones will say that they don't treat chickens and that might be quite frustrating as a chicken owner with a sick bird but it is far more annoying to find a vet that will treat chickens, pay them good money and later find that they actually don't know much and you could have got better advice here for free. The beauty of this site is that we can all share our collective experience to help each other and improve our own knowledge. I am indebted to all the people whose posts I have read in order to gain the knowledge I have and hopefully that will continue for many years to come.
Best wishes
Barbara
