Interpreting equine bloodwork (the ABCs of CBC)

First, an anecdote...
Pictured left is Riley, age 6 months, when his baby cuteness was on the wane. It was also about the time he started behaving oddly-- standing isolated from his pasturemates, yawning repeatedly after eating, and chewing wood. The symptoms went away on their own eventually, but not before I spent a lot of money.

I got a dire phone call from the barn owner, "Something's wrong, he's either sick or mentally disturbed..." The vet was summoned, bloodwork ordered, and a course of Gastroguard treatment began. Riley got 1/2 tube a day for three weeks, (at $30/tube, mind you) and he was still knawing on the fenceposts like a beaver. More troubling, the bloodwork was off -- so much so that we repeated it two more times in the course of treatment. Okay, time to escalate things. I trailered him him to the Midatlantic Equine Veterinary Facility in Ringoes, NJ. The point of the trip was to confirm a suspicion that he had ulcers. At MidAtlantic, they took yet another sample of bloodwork and did an endoscopy, ultrasound, and radiographs. From this we learned that there in fact were no ulcers, and as far as they could tell, he was in perfect health. Unlike the three scary blood reports we got at home, the bloodwork at the clinic was AOK. Apparently he was fine and the trip was for nothing. I was positively giddy with joy and gratitude -- until I went to the front desk to pay the bill. From personal experience and from talking to others, I have learned a rule of thumb for for equine clinic visits: 1 day = $1K.

Every time I spend money on unnecessary vet procedures, I have an epiphany about horses. Horses do things, behave in ways, and have ailments that much of the time just can't be explained. Experience has borne this out time and time again. So why throw fistfulls of money at equine vets, clinics, massage therapists, chiropractors, and farriers? Because when I ask myself, "Have you do everything you can for him?" I want the answer to be "yes." That is why my finances are always on the ragged edge of disaster, and likely why my veterinarian has a shiny new truck.

The useful info...
I'm digressing a little. My reason for sharing this experience is that when Riley's initial bloodwork came back, the fibrinogen level was elevated--four or five times the normal value, which indicates raging inflammation somewhere. My vet could not explain it. Back home I googled myself into greater knowledge, and I found that fibrinogen increases as part of an acute response -- it would not stay elevated over time w/o other blood values changing too. Riley's bloodwork did not make sense. I also learned, after all was said and done, that fibrinogen tests in the field can be unreliable. That's why Midatlantic's bloodwork looked normal when the field tests suggested one hoof was in the grave. Alas, there's money I'll never get back...

For anyone who wants to understand their horse's bloodwork, I recommend these articles:

Why Perform the CBC, and How Can the Information Be Used to Manage Cases?
http://www.ivis.org/proceedings/aaep/1999/285.pdf
This is a must-read for horse owners who like to go a step further than just following the vet's orders.

How to speak CBC in one easy lesson
http://shady-acres.com/susan/cbc.shtml
For those who like a more concise summary.

Bloodwork interpretation as an aid to horse training
http://www.gateway.net.au/~mcvc/horses/red.html
One more, which is actually a three part series; and the info is oriented to the performance (racing) horse.

Apropos nothing, and because I have posted numerous entries without once referring to Harvey, here is a picture of my 21 year old OTTB. He is probably 19 here, and he doesn't look much different now. God bless him he has good genes and is aging well. At some later date I'll bore you with a mawkish, sentimental tribute to "the Harvster."