Potential new sources of hypoglycin A poisoning for equids kept at pasture in spring: a field pilot study.

The research article investigates potential sources of Hypoglycin A (HGA) poisoning in horses during the spring season. It reveals that horses are exposed to this poison through sycamore maple tree seeds and seedlings, often leading to a condition called Equine Atypical Myopathy in Europe.

Objective of the Study

• The purpose of this pilot study is to identify additional potential sources of HGA poisoning during the spring season when grazing horses are at risk.

Methods

• Researchers collected fallen seeds and growing seedlings from sycamore, Norway, and field maple trees at two-week intervals during spring 2016.
• They also gathered rainwater from wet seedlings in early April and, in mid-May, collected seeds of the box elder and common ash trees, along with the inflorescences of sycamore maples.
• The presence of HGA in these samples was confirmed through high-performance thin-layer chromatography.

Results

• They found Hypoglycin A in all samples from sycamore trees, including the rainwater.
• The seeds and seedlings from Norway and field maples tested negative for HGA.
• The box elder seeds in the study area did not contain a seed inside their husk, thus also tested negative.

Implication of Findings

• From the maximum HGA concentrations identified, the researchers extrapolated that, under certain conditions and locations, about 20g of seeds, 50 seedlings, or 150g of inflorescences or 2 liters of water in contact with seedlings might contain the maximum dose of HGA that a horse can tolerate in a day.
• This information is crucial as it helps identify potentially dangerous sources of HGA poisoning and could help in designing preventative strategies against equine atypical myopathy.