We have a couple of farm ponds that are the only sources of water on the pastures they are in. We also fish in these ponds. Some years they get muddy, and we see a lot of algae. I worry that the algae aren't good for the cattle or the fish. How big of a problem is this?
DR. MCMILLAN'S ANSWER:
At least in the Deep South, farm ponds are a common source of free and readily available water and recreation. But you are correct, they are a two-edged sword.
Depending on the size of a pond, its design, and its water flow, cattle can destroy fish habitat. They can also reduce the pond's water capacity and water quality. All of this can have a huge, negative effect on cattle health and performance. With unlimited access to a pond, cattle will stand in the water and eliminate there. This can then be a source of many diseases, including Leptospirosis. In some areas, liver flukes can also infect cattle.
The moist areas around ponds are a source for coccidia and intestinal worms. Foot rot can also be a problem since the hooves and interdigital skin are softened by standing in water for long periods of time. The moist ground around ponds is a perfect place for bacteria that cause foot rot to survive. Also, over the years, I have seen several snake bites that most likely happened around a pond. And we've not even discussed the impact all of this has on the fish, or the algae problem.
While most algae are not toxic, some species of blue-green algae can be dangerous, even fatal, to pets, people and livestock. Cyanobacteria are not algae, but rather bacteria that contain chlorophyll. Some species can produce neurotoxins that lead to muscle tremors, difficulty breathing, seizures, profuse slobbering, diarrhea, and rapid death. They can also lead to a buildup of hepatoxins, which can cause sudden death or liver failure. Liver damage can lead to photosensitization, a skin condition causing non-pigmented areas of skin to crust and peel.
So, what can you do? One option is to fence the pond off and then gravity feed a water trough below the dam. If that isn't possible, a pump could be used, but that requires a power source. The last alternative is to only allow access to a small area of the pond where a heavy-use area has been created.
Clean, fresh water is the most important input for any livestock operation, and providing it is always a top priority. I assure you it pays dividends many times over. And the fish will appreciate it too!
Please contact your veterinarian with questions pertaining to the health of your herd or other animals. Every operation is unique, and the information in this column does not pertain to all situations. This is not intended as medical advice but is purely for informational purposes.
Write Dr. Ken McMillan at Ask the Vet, 2204 Lakeshore Dr., Suite 415, Birmingham, AL 35209, or email firstname.lastname@example.org.
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