Don’t piss me off

especially when I’m right.

After my rant yesterday I took them time to look up one of the authorities on CWD and send them an email asking if the CWD prions were present in fully formed antlers.  I got back a response this afternoon:

Thanks for directing you question to the CWD Alliance. According to the most recent research, infectious prion proteins are present in the antler velvet of CWD infected animals when their antlers are growing and the velvet is engorged with blood. As past research has demonstrated that prions are present in all blood of infected animals, this is not particularly surprising. Also, we know that infectious prions can be present in the marrow of skeletal bones, mainly due to the blood present in the marrow itself. To date, I am unaware of any study that has tested for CWD in hardened antler. This is likely the case because of what we know about the bone-forming process.

Like all bones, antlers are formed through a process called ossification.  During this process, osteblasts (which are mostly a matrix of specific protein synthesizing cells, prions not being one of them) extract calcium from the blood and deposit it in the forming bone matrix, which is largely cartilaginous in the early stages. When full ossification is complete, there is no blood remaining in the hardened bone. In antlers, there is no marrow in the core of the structure as there is in skeletal bones. So, it is highly unlikely that any blood-born prions remain in or on the hardened antler.  But, as stated before, when the antlers are actively growing on a CWD-infected animal, infectious prions will likely be present in the new tissue, particularly in the velvet.

It seems that no matter how well we document facts about CWD, people will still choose to believe what they wish. In your case, the issue is simpler than whether or not CWD prions are present in hardened antler. Research in 2009 (Trans-species amplification of PrPCWD and correlation with rigid loop 170N, Virology, Volume 387, Issue 1, 25 April 2009, Pages 235-243. Timothy D. Kurt, Glenn C. Telling, Mark D. Zabel, Edward A. Hoover), showed that CWD prions do not replicate in canines (dogs, wolves coyotes, etc.). Essentially, that means that dogs are not susceptible to CWD.

Tell your friends to chew on that (pun intended).

So basically, yes, the prions are present in the velvet of forming antlers, and they are present in the not yet fully formed antlers themselves.  However, once the antlers are fully formed and hardened and the velvet has been shed there is no blood or marrow present in them for the prions to be present in.  And it doesn’t even matter because canines aren’t susceptible!

Now to go piss off someone else……

(and yes, I have permission to post this here!)