Water Hemlock and Goats: Toxicity, Symptoms, Prevention

Photo credit: Wikimedia Commons

In early spring when things are just starting to green up, watch out for water hemlock. It is a horrendous and unforgettable way to lose a goat. I read a fascinating university publication a couple of years ago after we buried our 2nd goat and started to put the pieces together. It was from 1920 and they tested various feeding methods of water hemlock to sheep to learn about toxicity. If you’re interested in this topic enough to read 23 pages or so, I highly recommend The Poison Parsnip Or Water Hemlock, available for free on Google Books.

In earliest spring, water hemlock is one of the first plants to grow. Eager for greens, goats will eat it because little else is available. Even well fed goats long for spring greenery. It is at this point that water hemlock is its most toxic above ground and it is at this point you need to be diligent with your otherwise smart and good-choice-making goats. We just keep ours up off the bottom where it grows until the grass has grown up. Living on a creek, new seeds come in yearly so it’s not possible to be sure they’re eradicated.

The root is always extremely toxic. If picking it, you want to wear gloves and try not to break off pieces in the water, because the juice will float downstream and it only takes a small amount to be fatal – just ask Socrates, who famously died by hemlock poisoning.

As summer draws on, the leafy parts lose their toxicity and are fully edible. This was confirmed in the booklet I read – large amounts could be fed with no ill effect. My own goats seem to have figured this out and will eat it later in the season, which is why I think they get confused about it in early spring – goats are otherwise pretty astute about what they can eat.

Once it blooms, both flowers and seeds are again highly poisonous. Mine avoid it by then so we don’t make efforts to remove them. The neighboring cows seem to have no issues even with flowers/seeds, but I wouldn’t bet a life on it!

Symptoms of Water Hemlock Poisoning

Oregon State has a great fact sheet on water hemlock, including symptoms, so I’ll leave it mostly to them, but I’ll tell you how it looked in our own herd.

The first was a kid not quite weaned and due to go to his new home that weekend.  I had taken a very rare–during kidding season especially–outing and was not home, but he was found severely bloated with abundant green foam around his mouth and on the ground around his head.  This can indicate other issues, but in hind sight based on the time of year and our experience the next year with a nursing doe, I feel quite confident it was hemlock.  They’d been on pasture long enough to not have issues transitioning so it was quite surprising and out of the blue.

The next spring, I’d been doctoring a yearling doe for pneumonia who had been quite ill.  She was well on the mend and finally had a strong appetite again, but it was early enough there was nothing to eat but hay, or so we thought.  We heard her crying out in a loud, gasping way and I ran to see what was wrong.  She was also bloated and laboring excessively to breathe, with abundant green foam.  She displayed signs of extreme pain, head pressing against the wall, alternating with panicked movements and overall restlessness.  I was waiting for a vet to call back when she died.

The year after that, we had just gone to bed and had the windows open when I heard the same tone of cry coming from the doe herd.  This time, I was prepared and we caught it early.  I dosed liberally several times over an hour and a half with activated charcoal.  This doe presented with bloat, severe distress, labored breathing and frequent crying out.  Again, there was nearly nothing growing yet, ruling out a more common cause like frothy bloat.

From the linked article above at Oregon State comes this important information to consider if you suspect one of your milkers ate hemlock:

“Do not burn the plant, as the smoke can contain deadly toxins. In fact, hemlock is so poisonous that some of poison hemlock’s alkaloid compounds have the ability to pass into milk when animals feed on sublethal amounts of this plant, which can adversely alter the flavor and safety of milk used for human consumption.”

Prevention

Because water hemlock looks similar to other plants, it’s critical to identify accurately in your pasture.  It’s a biennial and harder to spot in its first year, but come late summer, the tall, flowering, second-year plants are easy to spot even among the tall grasses.  If you can collect the flowers before or right when they seed, they can be disposed of in a plastic garbage bag.  Contact your local landfill to find out where their noxious weed disposal sites are.

When handling the flower heads, wear gloves at least.  I’m not generally a worrying type, but this plant is worth all the extra precautions, so you may want to wear mouth and eye protection as well and plan to change into fresh clothes when you’ve finished.

The best method of prevention we’ve found is to simply keep goats off of low lying areas until the grass and other plants have come in strong for spring.  Given lots of options, goats will generally avoid things that aren’t good for them.

The combination of mechanical removal of flower heads and prohibiting early spring grazing near the creek has helped us avoid any more issues in the years since.