The arrival of May means now is the time to ensure cattle feeding sites are properly managed and kept clean. Excess manure can cause a multitude of issues, ranging from increased fly populations to dirty water.

Joel DeRouchey, professor in Kansas State University’s Department of Animal Sciences and Industry, said that from a sanitation standpoint, any manure that is lying around could end up downstream, especially during times of heavy spring rains.

Manure that gets caught in spring rains and ends up downstream could spell trouble, including for cattle, he said.

“We know the environmental consequence, even from small sites, of a lot of manure that builds up,” said DeRouchey, a livestock nutrition and environmental management specialist for K-State Research and Extension. “From a phosphorus, nitrogen and bacterial standpoint, that could run off into our surface water, often times in the same area where we expect those cattle to be drinking.”

Unclean drinking water for cattle isn’t the only problem that excess manure can cause. Flies can wreak havoc on cattle as well, even if they don’t seem to be a noticeable problem to the producer.

“Sites that have excess manure and wasted hay are perfect environments for flies to lay eggs and begin to emerge,” DeRouchey said. “You have to recognize it only takes five stable flies per leg to reach an economic threshold of decreased performance. So we’re talking 20 flies total per animal.”

In fact, recent research continues to show how flies can have a real economic impact on cattle.

“Research in Nebraska, a grazing study, found that average daily gain was reduced about a half a pound over an 84-day trial when insecticide wasn’t applied versus when it was,” DeRouchey said. “We can directly relate that to the amount of flies that were present in that particular study. So this is not a minor potential impact on performance.”

Keeping flies under control and taking every measure to ensure that flies are not a hindrance to cattle is important for producers.

“We can certainly use insecticide to help mitigate (flies), which is a valuable management tool,” DeRouchey said. “The other side is to just decrease the fly population in that given area. The way we can do that is by getting these sites cleaned up and getting that manure piled up and spread as soon as possible.”

Heading into summer, there are fewer opportunities to spread manure because of the growing crops. So get that spring cleaning done sooner rather than later, he advised.

A K-State publication titled “Managing Stable Fly Production at Pasture Feeding Sites” is available online or at local extension offices throughout Kansas.