Monitor animals for algae poisoning

It's time to think about potential summer hazards for our livestock and pets.

It is quite common for me to get inquiries about algae poisoning during the warmer months. Here's some practical guidance for keeping animals safe:

Summer risk

and causes

Cyanobacteria (blue-green algae) thrive when water is warm, calm, and high in nitrogen and phosphorus - conditions common in late spring through early fall. Hot weather, longer stratified seasons and inputs from fertilizer, manure and failing septic systems can increase bloom frequency and toxicity. Blooms can form surface scums, mats, pea soup-colored water or paint like streaks but may also be invisible while still toxic. The color of water can be quite variable.

Blue green (cyanobacterial) blooms are most likely in warm, slow moving, nutrient rich water.

Keep animals away from scummy or discolored water, provide safe alternate water and seek veterinary care if exposure is suspected.

Animals are affected

Dogs are especially at risk from swimming and licking fur. Cattle, sheep, goats and horses may drink from ponds or wade at watering sites.

Cyanotoxins target the liver and nervous system; onset can be minutes to hours and may be rapidly fatal.

Dogs, livestock and other animals are most often poisoned by drinking contaminated water, swallowing mats or licking contaminated fur.

Neurotoxins can cause tremors, seizures, respiratory paralysis and sudden death. Hepatotoxins cause vomiting, jaundice, bleeding disorders and liver failure. There is no universal antidote.

Prevention

Assume any visible bloom is potentially toxic. Keep animals away from water that looks like pea soup, spilled paint, foam or has a foul odor.

• Provide reliable alternative water sources (wells, hauled water, fenced off troughs) and harden watering points so animals don't loiter at ponds. Install water sources away from water suspected to be contaminated.

• Reduce nutrient inputs by managing fertilizers, maintaining riparian buffers, controlling runoff from feedlots and pastures, and fixing septic leaks.

• Monitor frequently in summer and after heavy rains. Photograph suspicious blooms and report them to local health or environmental agencies. When in doubt, "stay out" and keep animals away.

If exposure occurs

• Remove animals from the water, rinse fur with clean water and prevent access to the source.

• Seek veterinary care immediately. Early gastrointestinal decontamination (if advised by a veterinarian), activated charcoal within the first hour, aggressive supportive care (IV fluids, oxygen, anticonvulsants, blood products) and monitoring of liver enzymes and clotting can improve outcomes.

• Report suspected poisonings to health departments and veterinary diagnostic labs. Sample collection protocols exist for water and animal tissues to confirm cyanotoxins.

Conclusions

• Keep animals away from scummy, discolored or odorous water.

• Provide alternate water and fence off ponds.

• Rinse exposed pets and call your vet immediately.

• Photograph blooms and save water samples.

• Reduce nutrient runoff.

- Don Llewellyn is the Washington State University livestock specialist in Lincoln County. Email him at don.llewellyn@wsu.edu.