Ag Instructor Vic Martin: Livestock, Water and Algae

Great Bend Tribune
Published June 24, 2018

First, the Drought Monitor which didn’t include last Tuesday night’s rain showed some easing in the western third of the state.  With the precipitation and cooler weather of the last week, much of the state should show improvement with this coming week’s report.  This column normally focuses on crops but today, with the official start of summer, a column on livestock to change things up a bit.

Those in the Barton County area are likely familiar with the problems over the last few years at Veterans’ Lake in Great Bend during hot summer weather.  Blue-green algae blooms that resulted in toxic substances in the water that were hazardous to people and pets.  These blooms result from an abundance of nutrient minerals in the water, primarily nitrogen and phosphorus, resulting from fertilizers and/or manures entering the water.  Blooms typically present a hazard in more stagnant waters.  The result is an overabundance of the organisms and they can release toxic compounds, especially as they die off.  They can release two types of toxins – neurotoxins that naturally affect the nervous system and hepatotoxins affecting liver function.

These blue-green algae actually aren’t algae at all but cyanobacteria that can reproduce quite rapidly, doubling in population within twenty-four hours.  There are specific species that will release these toxins and these compounds can be lethal to animals and people.  You can differentiate them from mosses as these organisms tend to feel slimy, almost paint like.  The problem commonly occurs during stretches of hot weather and is exacerbated by high nutrient contents in the water.  A problem that can occur in easily in ponds used to water livestock and even in stock tanks.  However, there are steps to take that can minimize the problem. 

First, if you suspect a problem, contact your local extension agent and they can help you obtain a sample and send it off to the K-State Veterinary Diagnostic lab in Manhattan.  So what can you do?

For Ponds

  • The algae tend to form on the downwind side so fence off that area. 
  • If withdrawing water from a pond for livestock, take it from the middle of the pond and from as deep as practical as the blooms tend to be at the edge.
  • For a small pond and stock tanks, there are chemicals to help keep the problem in check which may be applied but caution needs to be taken to prevent harm to livestock. 

For stock tanks

  • If practical, drain and clean the tank every ten days to two weeks during hot weather.  This has the added benefit of increasing livestock water intake with cleaner water and may help keep mosquito populations down.
  • If cleaning is impractical, there are algicides available to keep the blue-green algae in check and that are safe to livestock when label directions are followed.  Copper sulfate is one product but the label must be followed to protect livestock.  Unscented bleach is also an option but again care must be taken.  The general rule for bleach is two to three ounces per fifty gallons.  If you have questions contact your local extension office.

Is this a huge problem in our area?  Normally not, but as in many things an ounce of prevention is worth a pound of cure or the livestock lost.