The last couple days have been pretty devastating for my household. On Sunday, our big draft cross mare was energetic and happy. We took her out riding and noticed no behavioral or physical changes. On Tuesday, I woke up to the horses freaking out and quickly grabbed a flash light and headed out to check on them. It was apparent that one of the horses had attempted to go through the fence and in doing so had managed break an industrial extension cord in half (the cords are attached along the fence to provide power to the electric water heaters, its not ideal but its been working). My barely awake brain checked all 8 horses legs and chests for any signs of damage which wasn’t an easy task as my horses are not fond of head lamps. There was no signs of damage but I went back out in the light to check them better.
When I went out in the morning, it was immediately apparent that the draft cross mare was not doing well. She was an 8 year old mare with a nearly 6mo old filly. Her movement was very odd and she was stumbling like she was drunk, I watched her trip over a snowbank and fall to her knees. Her front feet were crossing over when she walked and she was walking aimlessly but not stopping. She had several small gashes on her face and it was obvious she had been the one who had tried to go through the fence. I called the vet immediately and began to try to catch her.
Getting closer to her I was even more concerned. She was walking into trees and non-responsive to stimuli. She did not respond to a lead rope around her neck and dragged me across the pasture. My boyfriend and I managed to direct her into our round pen by pushing into her shoulder. Once in the round pen she began to compulsively circle, occasionally brushing into the boards or in some cases running into them head on. The entire time she passed gas and had an acidic smell.
Once the vet arrived we had to sedate her. Once under sedation she stumbled and fell down which is when the vet took blood and urine samples (she was intermittently urinating). She was up again in less than 20 minutes and had to be sedated again. Operating under the assumption that it there was head trauma, although the possibility of hepatic encephalopathy was considered, she was given a steroid and a anti-inflammatory. The vet left a shunt in her neck so we could continue to administer medications over the next 24 hours.
Around 12-2pm she appeared to be more responsive to stimuli, her ears were moving when her name was called and she even stood still for periods of 5 minutes. Around 4-5pm she began stumbling (at one point fell to her knees 7 times in 15 minutes) and then stayed down for ten minutes. I made several calls to the vet who was on another emergency call and just after 7 she got back to me with the blood test results. My mares GGT level was 717. It was not head trauma. We immediately opted to put her down.
We considered an autopsy but the vet did not believe the autopsy would reveal cause of death and we were afraid of leaving the body out over night if she had been cut open. We instead took blood samples from her foal.
The foal’s GGT level is 33 and the vet believes that the liver failure was caused by an environmental factor. The vet and I tore apart the hay bale the mare was free feeding from looking for clover and found none. We have had the same hay supplier for at least 6 years. The mare was occasionally given grain and mare feed, both of which are the same brands I’ve been buying from the same supplier for the last two years. The mare feed has been fed to two others horses who show no signs, along with the foal who also shows no symptoms. Besides a mineral and salt block, theres nothing out in pasture. We’ve had snow for the last month and half, there’s no grazing. The mare was in the same 4 acre paddock for the last 3 years.
We are devastated and desperate for answers. Nothing I’ve read about hepatic encephalopathy adequately describes what I witnessed or how fast it came on. We are starting all 7 remaining horses on milk thistle and looking for a new hay supplier, does anybody have any suggestions?
Where are you located? It does sound like poisoning with resulting liver failure. I’m trying to recall the name of the plant, but a woman I sold a Percheron mare to had bought and renovated a horse property in NH. One of the paddocks ran alongside the driveway and the driveway was lined with a shrub that it turned out is poisonous to horses and caused either liver or kidney failure with the result being the mare had to be put down. The woman had no idea that landscaping bush/shrub was even a threat. The horse just reached over the board fence at some point and ate enough to kill her. She, of course, ripped it all out after that.
Tansy Ragwort causes liver failure. Johnson Grass poisoning causes symptoms similar to what you relate. https://equusmagazine.com/management/10-most-poisonous-plants-for-horses-8208
Very sorry for your loss.
I’m in British Columbia, Canada. There’s no tansy ragwort growing now or in the hay, but I can check the hay for johnson grass. The vet believes the neuropathy was all caused by the liver failure. We don’t have any landscaping shrubs besides in the flower beds alongside the house (way out of reach of the horses). We are having the vet out today to test the other horses in hopes to narrow down the possibilities.
We’ve even considered that she was intentionally poisoned because of the fast onset but she was pastured with her foal, a yearling, and another mare, and she was the least approachable of all 4. Our other four horses are pastured in an adjoining 5 acres with access to the same water supply but a different hay bale, so we are going to take samples from 2 of them as well as the other mare she was pastured with.
I’m so sorry for your loss. Please keep us updated as to your findings.
Ask your vet to check into bracken fern poisoning. I live in the BC interior, and there’s been a case in my area over the mid to late summer. Thiamine injections have resulted in a great improvement, but the jury’s still out on how the mare will fare through the winter. We’ve had frozen ground and snow (some’s melted, we had 2 feet by mid-November), but bracken is still accessible.
While I understand your concerns about having a carcass sitting around, as I too live in a rural area, I think there’s a great deal to be learned from autopsies, so I don’t think your vet gave you necessarily the best advice. I lost a Friesian mare last winter to MEED, which would never have been diagnosed without a full autopsy, and all of us involved learned a lot from the whole experience.
Ive seen liver failure by ragwort before, and it had none of those symptoms (not that my experience should be taken as evidence as every case is different)
That case started with severe fluid retention and swelling of legs from memory. Horse seemed fine other than it was so stocked up it had trouble moving.
Ragwort can show up years after exposure too
We rolled out a couple of our bales yesterday to be sure it wasn’t alsike poisoning, and sure enough the first bale we unrolled was riddled with it. The second bale we rolled out had next to none. Because we found the alsike, we did blood tests on all 7 other horses.
Their GGT levels were 33, 37, 47, 29, 105, 125, and 166. I can give you guys more details on each horse if you’re curious. I’m waiting for the vet to email me full profiles for each horse, but she called to give me the GGT levels.
Everybody is getting milk thistle for the next two months and then we will retest.
We have found someone who sprays their hay fields for clover and managed to secure enough hay from them for the next month while we look elsewhere for a new supplier.
If you’re still concerned about liver, please be aware they can still have liver inflammation, it doesn’t always show up in the GGT. My horse was showing signs of a liver issue (long story, but I’m hyper aware of signs with him now and so is my vet) and though his liver panel came back squeaky clean, his SDH was elevated and continued to climb for over a month and all the while, a standard liver panel remained normal (GGT, AST, ALT). Ultrasound and biopsy confirmed liver inflammation.
If I suspect a liver problem with my guy, I put him on Platinum Liver Support. In addition to milk thistle, it also has N-Acetyl Cysteine (NAC) which acts in a similar manner to SAMe but a heck of a lot easier to dose. I do give him extra milk thistle power as well though I probably don’t need to.
I was just about to recommend adding the NAC. Thanks for mentioning that PP already has a liver support formula.
To the OP, condolences on the loss of your horse, and kudos to you for the excellent and diligent search for causes.
