Deep Pectoral Myopathy

December 12, 2016

We've had our fair share of learning things the hard way. Sometimes, we scratch our heads and think maybe those guys raising chickens inside big concrete buildings are doing something right.


Don't worry, that thought doesn't stay in our heads too long. But a late April or May snow storm, and we are outside in snow suits trying to cover our chickens up in rows of plastic, with heat lamps, and their feeders under tarps... sometimes a building seems like the sane thing to do.


We've had an outbreak of Mycoplasma (respiratory infection) that caused us to cull our entire flock in 2013. We've had predator issues that took out my favorite rooster one year, as well as many from his harem.  But all in all, things have gone pretty well on our little farm.


This year, after raising Cornish Rock Cross breeds for almost a decade, we had our first evidence of "Deep Pectoral Myopathy."


If you want the technical, scientific and medical rundown, you can get it from:


Again, 9 years of raising chickens and we have never seen this issue. Let's put it in my words...


Cornish Rock Crosses have been bred to be SO big, that the inner muscle (the tender) that sits between the breast and the sternum AND is the muscle that controls wing flapping... it is basically constricted in there by the big breast muscle - that large chunk of white meat everyone eats them for. IF the birds use their wings a LOT, the tender can swell, and blood flow is constricted. This can cause the blood vessels supplying nutrients to that muscle tissue to hemorrhage. This in turn creates an issue where blood is no longer being supplied to this tissue and the cells start to die. Eventually the entire muscle atrophies and dies. 


This is particularly common to the Cornish Rock Crosses and other fast growing chickens, it can also happen to Broad Breasted Turkeys as well as standard roosters, though usually at an older age.



 Sorry big guy, you were bred to grow fast and tasty, but not to be flying about!


So why all of a sudden did we get this issue? I am not 100% sure why. Nothing we did this year was necessarily different than other years. We raised the same breeds of birds (we have no reports so far of this condition on our RANGERS, just the Cornish Rocks.)  Here are a few things that have been different:


1) The very last batch of Cornish Crosses we raised this year were also raised with our turkeys. By the time these guys came along, the turkeys were getting quite mature. These guys may have been being bothered by the larger birds, or had to scout farther for food if the turkeys were guarding the feeders.

2) Just a week or so before processing, we lost quite a few of these guys to predators. Larry saw a hawk prowling around, and we had evidence of a Great Horned Owl - one of the few predators my dogs are not good guarding against. We lost some of the birds, and several others were damaged. Now, they seemed to be picking off the young Rhode Island Reds (the predators could have flown off with those smaller, lighter birds) but they may have caused a ruckus.

3) We've also had more folks coming and going in the bird runs. We've allowed helpers to help us catch birds, as well as my daughter, who sometimes gets a little overzealous.


All of these things could have put the birds in a tizzy, causing them to try to hustle about. They are pretty heavy, and they will use their wings to help them move if they are trying to run. Being picked up incorrectly could also cause some damage here. So we have some options for eliminating this issue.


A) No more visitors in the run. These birds are used to our comings and goings, and we know how to move around them to not get them excited. Folks can easily see them from the fenceline of the garden or the orchard, so there is no need to bring folks in. This has a secondary benefit of BIOSECURITY. No one brings stuff in on their shoes, or for their own chickens, they don't bring stuff out, either.

B) Only Long Shadow Farm folks will be allowed to capture birds  I love having helpers on the farm, but unless folks are working here for a period of time and can be properly trained, only we will catch birds. That includes Shannon unless she can stay calm. We pick them up carefully and load them into our transport crates. We don't chase them if they run from us, we are gentle and slow moving around the birds.

C) Only trained folks will be allowed to handle the live bird on processing days. Excessive wing flapping can also happen on processing day. This includes loading them into the cones.  This is another step where this can happen. We need to keep the birds calm during this time.

D) We no longer raise Cornish Crosses  I do not think we will exercise this option, but I may limit them. I am really growing to like the Ranger breeds, and am going to try a new one this coming year. They are heartier birds, less prone to illness and injury, but do take longer to grow to size. We will consider this in coming years if the first three measures don't make a difference.


That being said, you may be wondering,  "Do my birds have this issue?"  The likely answer is actually NO!


This seems to be isolated to ONE batch of birds, our last batch of conventional broilers. The organic birds of the same time frame were  a) butchered a week earlier, and missed the owl attacks completely and b) the balance of this conventional batch were all sold to one customer who we have already communicated with. Any other birds from this batch that were not sold to said customer were kept for ourselves, due to injuries from the owl! We have actually already eaten them all, and did not see this issue ourselves. 


As an aside, we eat the birds we don't sell. We eat birds with visible scars and damage to their skin - from predators, or aggressive breeding. We eat the birds that get bruised on their wings or legs. We eat any bird that visibly we would not sell. Deep Pectoral Myopathy is NOT VISIBLE ON A WHOLE CARCASS. You can't see it until you cut open the breast. Still, we have never seen it here in our own house, and we are eating the birds that have been attacked by predators, that have ambulatory issues or any other concern, and we have not seen it.


The USDA states that this is in no way a food safety issue. The effected tissue can be discarded, but the rest of the bird is fine for consumption. The images we saw from this customer show Stage 1 myopathy, meaning it likely happened within days from processing, not weeks. Pull up the Aviagen PDF linked above to see pictures, just maybe not on your lunch break!


Again, this seems to be an issue for the Cornish Crosses, and if we can not control this with the steps above, we'll be looking to raise more Rangers in the future!

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