Todayโs path rounds are on ๐ซ๐๐ ๐ฆ๐๐ฉ๐ฅ๐ ๐ญ๐จ๐ฑ๐ข๐๐ข๐ญ๐ฒ!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐๐ ๐ฆ๐๐ฉ๐ฅ๐ ๐ญ๐จ๐ฑ๐ข๐๐ข๐ญ๐ฒ, as the name suggests, is a toxicity that comes from eating the leaves of the red maple tree. Specifically, ๐ฐ๐ข๐ฅ๐ญ๐๐ leaves like those found after a hard frost, or falling off of pruned or fallen tree limbs.
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
This disease occurs in horses!
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
The toxin in wilted red maple leaves is thought to be either ๐ ๐๐ฅ๐ฅ๐ข๐ ๐๐๐ข๐ or ๐ฉ๐ฒ๐ซ๐จ๐ ๐๐ฅ๐ฅ๐จ๐ฅ. These toxins are directly toxic to the red blood cells, causing their destruction.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
Destruction of RBCs leads to severe ๐๐ง๐๐ฆ๐ข๐ (low numbers of RBCs) and ๐ข๐๐ญ๐๐ซ๐ฎ๐ฌ (yellowing of the tissue). Another notable consequence of RBC destruction is ๐ก๐๐ฆ๐จ๐ ๐ฅ๐จ๐๐ข๐ง๐ฎ๐ซ๐ข๐, or blood in the urine. Not only does this produce a dark brown to red urine, but it can also stain the kidneys very dark brown to black, due to accumulation of ๐ก๐๐ฆ๐จ๐ ๐ฅ๐จ๐๐ข๐ง (the oxygen carrying component of blood) within the kidney. Hemoglobin is directly toxic to kidney cells, so eventually this can lead to kidney failure.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
Typically this condition is diagnosed based on a history of exposure to red maple leaves, combined with the clinical findings of anemia, icterus and dark red urine. If the horse dies, the very dark kidneys can be seen at necropsy.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐? ๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ฉ๐ซ๐๐ฏ๐๐ง๐ญ๐๐?
Treatment focuses on absorbing the toxin, so the veterinarian will often administer activated charcoal through a ๐ง๐๐ฌ๐จ๐ ๐๐ฌ๐ญ๐ซ๐ข๐ ๐ญ๐ฎ๐๐ (tube from the nose into the stomach). Fluids are also given at a high rate to help flush the hemoglobin from the kidney, to prevent kidney damage. The horse may also need blood transfusions to correct their anemia.
For prevention, removing access to maple trees is key! This can be done by fencing off the trees, gathering leaves or trimming branches.
๐๐ก๐จ๐ญ๐จ๐ฌ
1) What red maple leaves look like!
2) A horse with icterus showing yellowing of the ๐ฌ๐๐ฅ๐๐ซ๐ of the eye.
3-5) Examples of kidneys with hemoglobin staining. In the syringes, you can see very dark red to black urine!
6) What the pathologist would see under the microscope! The lakes of pink material are hemoglobin stuck in the kidney tubules.
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Lenz, T. Red Maple Poisoning. American Association of Equine Practitioners.
Photos 1-6 ยฉ Noahโs Arkive contributor Harmon and Howerth, Blackmon, Crowell licensed under CC BY-SA 4.0.
