Subject: Re: Founder
Sent: 11/13/96 2:09 PM
Received: 11/14/96 2:24 AM
From: Nanette Chastine, NanetteCII@aol.com
Reply-To: horsesci@mail.usyd.edu.au
To: Multiple recipients of list, horsesci@mail.usyd.edu.au

Gretchen,
Is your horse on thyroid supplementation because of cresty neck, and obesity?  If so, that is another thing to add to your list of founder causing incidents. From what I know, founder is caused by the blood vessels in the feet constricting (by you guessed it, any number of factors). This constriction pools the blood, and the naturally occurring toxins, leaving them with nowhere to go. Because of the construction of the of the hoof, the horny wall attaches to the sensitive laminae which in turn attaches to the coffin bone, there is no room for the pooling of blood and the rising levels of toxins cause the sensitive laminae to start dying. This causes the horny wall to separate from the coffin bone; this is when rotation occurs. After founder occurs once, with any amount of damage to the sensitive laminae, the blood supply to the hoof is compromised and founder can occur more easily. I am not an expert on this subject but what I have said here is passed on by our veterinarian and farrier since we unfortunately have a case of severe chronic founder here on our farm. Hope this helps.
Nanette Chastine, NanetteCII@aol.com
assistant farm manager/trainer, Chapel Farms Arabians

Subject: Re: Founder
Sent: 11/18/96 5:42 AM
Received: 11/18/96 3:03 AM
From: NanetteCII@aol.com
To: gretchenfathauer@ee.net

Gretchen,
Nice to hear from you again, especially to get more details about your gelding. Founder can be so frustrating, especially when you can't quite pinpoint what sets off each episode. Unfortunately, while our farrier is very good (one of the best that I have ever worked with), he is still human and prone to mistakes. Our mare that is now a chronic founder has what is known as a stress or mechanical founder. She is only 9 years old and we have had her for about three years. Last summer, she developed yeast in her toes (seedy toe) in her front feet. Since our farrier is here every 3-4 weeks, he would trim her and medicate her feet (we would medicate in between) every time he came. However, this didn't seem to be accomplishing anything so he took a small grinder and ground out the area in the toes that was so heavily infected. He has done this with success on a couple of horses, although not anywhere near as deep as he did with her. To be honest, we were horrified when he was done, she looked like she had cloven hooves, the vee that he had cleaned out came half-way up her foot. We asked about shoes on her front feet, but he thought keeping the area cleaned out and medicated would be sufficient. She is a broodmare, was in foal at the time, and being kept outside. To shorten the story, the stress was so great on her hooves and keeping the dirt out was an impossibility and she foundered, big time.  She has major rotation of the coffin bone, her right foot is worse and she tends to keep a soft spot on her sole, right in front of the frog, where the tip of the coffin bone rests. Luckily, we don't have to medicate her, however, we do keep eggbar/heartbar shoes on her, with wedge frog pads under the heartbar so that she constantly has pressure on the frog to help with circulation in her feet. Silicon is then placed in the sole area to help provide light cushioning and to help keep the coffin bone from rotating through the sole, of course there is a light leather pad to help hold the silicon in. Her toe is filed off where the excess growth occurs. After foaling she was better, but after weaning, she was much better. We keep her somewhat light in the weight department to help keep the load off her front end. She is in a small paddock with 2 pregnant mares that are quiet and on good days, she can be seen cantering around after the others. We also keep her hooves dressed daily with hoof dressing to keep the feet moist and supple, otherwise they tend to get hard as a rock and she seems to have a harder time getting around. We did not breed her back this year, we wanted her to get over as much as she could before re-stressing her with pregnancy and weight gain, and then we will see how she is next spring.

Now here is the interesting part: One thing that our veterinarian has discovered that we keep on hand, is nitroglycerin ointment. Research has found that a small amount placed on the arteries in the feet (the ones where you feel for the pulse in the feet), immediately upon onset of founder, can arrest the founder within about 10 minutes. The nitro will open up all of the blood vessels, allowing the toxins to be removed quickly. The pain will almost immediately increase to begin with since everything had been constricted before the nitros application. However, the horse will revert back to normal stance within a matter of minutes. Unfortunately, this doesn't work on chronic founder cases or cases where the onset of founder is well established. If you want more information on this, I can send you the name, address and phone of my vet, and you can get your vet to contact him.

Well, need to go, hope to hear from you again.

Nanette Chastine
Chapel Farms Arabians
Newnan, Georgia>NanetteCII@aol.com

This is part of a letter I sent to friends re Nanette Chastine's letter and the conversation I had with her vet:

I have put out some queries on the internet about laminitis, and got back some interesting responses on nitroglycerin ointment being able to knock out an acute attack in 10-15 minutes by addressing the real problem, a lack of circulation. There is more pain for a couple of minutes as the arteries begin to open up, but then they get much more comfortable, and it minimizes damage. The ointment has a very quick, brief and local effect.  You rub it onto the coronary band. I was looking for a magic bullet to have on hand if Max has another founder, and this sounds like it may be it. This stuff has to be given immediately, within the first day of acute founder. Not much use later on, but great if you catch it in time.  I am enclosing a copy of Nanette?s post to me. I called her vet. They are in the Atlanta, Georgia, area. Her vets are Dr. Hancock and Dr. Marcella. I spoke with Dr. Marcella. He prefers to give ketoson i.v. prior to putting on the ointment to kill the very transitory pain from the rapidly opening arteries. This pain is similar to the pain you feel when you warm your half-frozen hands up after getting inside from a really cold day. He tells me there is still controversy over how often you use it, and whether to shave the hair off first. Also that some people were administering it i.v., but he thinks the ointment giving a local effect is all you need and less traumatic.

He also suggested that I have Max tested for a pituitary adenoma, the tests being ACTH and DEX Suppression tests. This tumor causes elevated levels of cortisone in the blood. Other signs: proclivity to laminitis, low thyroid, longer curlier winter coat that is slow to shed, higher urine output, some loss of muscle and vision, tougher cases of rain rot, and a pot belly. He just said these signs keep getting worse slowly over a long period of time. The drug he uses to treat it, Permax, reverses these signs and makes them less founder-prone. This stuff is expensive, though--$100/month.

Anyway, the pertinent phone numbers: Chapel Farms Arabians--770-253-0355 Vets (Dr. Hancock and Dr. Marcella)--770-945-6001.  I am also sending copies of a couple of other responses to my query on nitroglycerin ointment. I got a response from a German equine vet who uses the ointment in conjunction with a lot of other drugs. He puts it on a different spot. His approach also sounds rather involved, and not something you could attempt on your own. This was bad news, really, as I had hoped I could have something on hand that I could use immediately. Being out in a remote area, I can't just get Indian Creek out at a moment's notice, which is something I miss! I am still hoping for a magic  bullet.  Dr. Marcella also feels that the autumn grass is almost as bad as the spring grass, which I did not realize. This amounts to a whole lot of confinement for my poor old moose! Marcella thinks keeping the paddock mowed, and feeding lots of low-carbohydrate hay, would be good as well. 

Below are two posts I received from a German vet who uses Nitroglycerin ointment in conjunction with many other drugs. Nanette's experience is that the nitro will work all by itself, though.

Subject: Re: Nitroglycerin ointment--Rx for Laminitis?
Sent: 12/18/1996 5:16 PM
Received: 12/18/1996 6:25 PM
From: Christian Bingold, 100257.2631@compuserve.com
To: Gretchen Fathauer, gretchenfathauer@ee.net

I am using Nitroglycerin ointment ("Neos-Nitro" , human med. preparation) on several laminitic horses during acute episodes with seemingly good results as an additional therapy. I am applying the ointment at the level of the prox. sesamoids bid over the vessels. With shaving the hair off I will get a skin reaction after about one week such that I have to quit - at least with the ointment I am using .

C. A. Bingold, DMV, Fachtierarzt f. Pferde
Klosterstr. 15 >68453 Otzberg - Germany
Subject: Re: Nitroglycerin ointment--Rx for Laminitis?
Sent: 01/01/1997 12:03 PM>Received: 01/01/1997 3:26 PM
From: Christian Bingold, 100257.2631@compuserve.com
To: Gretchen Fathauer, gretchenfathauer@ee.net

Sorry for not answering for such a long time.  The excuse is my moving to a new practice area near Frankfurt, Germany.  I stick pretty much to the protocol described at the original publication in the Equine Veterinary Journal sometime early last year (1996). I do shave the area over the vessels at the level of the proximal sesamoid bones and apply a 5cm string of the ointment medially and laterally on both forefeet bid. To keep the ointment out of the bandage material I cover the ointment with plastic foil. This will be repeated as long as the skin tolerates it - usually about  1 - 2 weeks.  Basic therapy for an acute case is as follows:
1. Day Butazolidine IV and Meclofenamic acid as NSAID's, the following days only Meclofenamic acid. 
2. For two to three days infusion of DMSO sid. 
3. For approx. 2 weeks Isoxuprine and Acetyl-Salicylic Acid as modulators of coagulation.
4. 2 to three days Acetylpromacine at low doses to lower blood pressure. 
5. Hoof bandages with cautious application of Lilly pads

I look at Nitroglycerin as an additional beneficial building block of my therapy. Alone - as the other pharmaceuticals also - it will not have much effect.  If I get acute cases without much previous damage to the hoof within the first 24 hours, they are mostly under control after one or two days. The treatment will be continued for at least 1 week, in most cases 2 weeks or depending on the changes longer.

Cortisone: NEVER USE CORTISONE IN LAMINITIS!!! Cortisone is absolutely contraindicated in laminitis. It aggravates or in certain instances causes laminitis.

Christian A. Bingold, DMV, Fachtierarzt fur Pferde
Practice Tel +49 6163 6500
Fax +49 6163 6511
Mobile +49 161 2604352
Neustadterstr. 24 - 64747 Breuberg-Sandbach, Germany
Private Tel +49 6162 982100
Fax +49 6162 982100
Mobil D2 +49 172 2906251
Klosterstr. 15 - 64853 Otzberg, Germany
Internet http://www.bingold.de (beginning sometime January)
e-mail 100257.2631@compuserve.com

Here is another response to my query on nitroglycerin ointment:

Subject: nitro from Rivas
Sent: 12/19/1996 10:17 AM
Received: 12/19/1996 3:42 PM
From: Southern State Medline, soumed@medinfo.wright.edu
1 UI - 96154312
AU - Hinckley KA
AU - Fearn S
AU - Howard BR
AU - Henderson IW
IN - Department of Animal and Plant Sciences, University of Sheffield,
UK.
TI - Nitric oxide donors as treatment for grass induced acute laminitis in ponies [see comments]
SO - Equine Veterinary Journal 1996 Jan;28(1):17-28
AB - The potential for participation of the arginine-nitric oxide system in the aetiology of acute equine laminitis has been assessed. Nitric oxide (NO), produced by the action of NO synthase (NOS) on its substrate l-arginine, relaxes vascular smooth muscle to cause vasodilation. An attenuated normal vasodilatory tone may characterise the pathogenesis of acute equine laminitis. An intravenous infusion of 10% l-arginine in 0.9% saline caused vasodilatation in the hoof of a normal pony and immediate reperfusion of laminal tissues in an acutely laminitic pony, detected noninvasively by near infrared spectroscopy (NIRS), but the amino acid had little effect on systemic blood pressure. Treatment of acute laminitis with glyceryl trinitrate applied topically to the pasterns reduced the typical 'bounding pulses' in treated limbs, reduced lameness and lowered systemic blood pressure. Nitric oxide is likely to participate in the multifactorial pathogenesis of equine laminitis.