My friend informed me her horse died of suspected cyanide poisoning. Are there common plants in Florida that cause this and what is the most likely culprit? The only plant my hay producer has mentioned being problematic in this area is coffee senna. I know he goes out and pulls it or sprays. He has cattle so tries to keep the hay fields free of it.
My friend thinks her horse may have intentionally been poisoned. I don’t know how likely that is, but her other 2 horses are fine. Also how would you get a horse to eat cyanide? That’s a disturbing thought and difficult to prove.
Ok. Step number one. Did her vet do a necropsy and confirm cyanide poisoning was indeed the cause of death? Or is it just “suspected”? If it’s just suspected, you are most likely dealing with a combination of sudden death in a horse plus grief plus a paranoid tendency and I would be sympathetic but not go down that rabbit hole.
How old was the horse?
Second, there are likely many ways to poison a horse, and the most efficiently would be IV which is why we don’t euthanize horses with oral meds.
If your friend thinks the horse was poisoned deliberately then I wouldn’t go crazy worrying about what’s in my field or hay because there would be multiple deaths from contaminated forage. Horses also die from grain contaminated with the cattle antibiotic ionophore.
Here is a link to common toxic plants in Florida. Cyanide is obviously associated with the seeds of fruit trees but you’d need a lot to poison a horse.
Not necessarily cyanide, but I would be concerned about Oleander or Yew. Because they are not only very toxic but used widely in landscaping in Florida.
There are a myriad of noxious plants in Florida. The ones I’ve been most cognizant of were nightshade, creeping indigo, castor bean, poke weed, and oleander. My question would be is this a pasture ,landscape contaminant, or hay? Most Florida hay beyond the native coastal or Tifton or peanut is from elsewhere. The pasture grass contaminants are the creeping indigo, pokeweed, nightshade, etc. the oleander is an ornamental plant you see in house landscapes.
Yes. True and you see that a lot in poor pastures or disturbed roadsides. And I’m not sure where the horse was located in Florida but here in central FL it’s been DRY DRY DRY for weeks and weeks and I think that makes Johnson or Sudan grass very toxic.
Yes. The native Coontie, or landscaping “cardboard palm”, or “sago palm” are all not palms at all but are Cycads. They have cyanide in them. Their seeds will kill a god who munches. Also, aren’t wilted red maple leaves a source of cyanide? We have them in Florida as well as other maples.
An often overlooked toxic tree here is s type of wild cherry. Dead limbs and leaves are very poisonous.
If the pasture is poor horses may eat toxic plants.
Also there’s Lantana, an orange and yellow flowering bush
that is blooming now in pastures. and is toxic.
Pokeweed grows abundantly in central Alabama, as does Johnson grass. My horses don’t eat either because they have adequate hay. I would think a horse would have to eat a lot of either plant because pastures here are full of both.
No.
Toxic, and cause intravascular hemolysis, hemoglobinuria, and renal failure.
Not cyanide, though.
The toxin is currently thought to be a strong oxidant, though no specific compound has been confirmed at present. (Gallic acid or a related compound is a suspect)
It’s my understanding that if you feed flax and let it soak for extended time frames, it starts to release cyanide. Just another thought if that’s the confirmed case.
When I lived in Florida, I lost a heifer to rattlebox in late summer/early fall. If hay was the source, it could have been in the bale. It causes severe liver damage. Irreversible cumulative effect.
while true, the amount of cyanide really isn’t enough, unless maybe you’re using a lot of flax and it’s building up. Soaked flax seems to be common in areas other than the US, and hasn’t posed a problem
