K-State veterinarians offer insight into why some calves have an aversion to silage
By LISA MOSER
K-State Research and Extension news service
When working with animals, often their caretakers have to use clues to understand what might be leading that individual to react differently than expected. And with feed resources, the experts at the Kansas State University Beef Cattle Institute recommend slowly changing feeds, especially when introducing silage.
In answering a listener's question about why calves were not willing to eat silage, the Cattle Chat podcast experts suggested following the cues of the cattle.
“When introducing silage, you are going to have to watch the calves closely to know when you can start increasing the amount in the diet. And with some groups, you may need to move more slowly,” said K-State veterinarian Bob Larson.
One reason that calves might have an aversion to eating silage is its smell, beef cattle nutritionist Phillip Lancaster said.
“Silage is a fermented feed resource, so it has a different taste and smell than calves are used to,” Lancaster said. “To make the silage more palatable, producers can add silage to the top of a feed source that the calves like. That way the calves have to work through the silage to get to what they prefer to eat.”
Because it is a fermented product, there can be variability in the batches, Lancaster said.
“If it is too wet, then it has a butyric fermentation that gives it a nasty odor that really turns cattle off on eating it,” Lancaster said. “If it is too dry, it can be moldy.”
Lancaster recommends that producers take a sample of the silage and have a fermentation analysis done to make sure there is the right balance of acetic acid, lactic acid and butyric acid. He also said silage inoculates added at the time the silage is made can provide bacteria at a high enough concentration to get an optimum fermentation.
If cattle are inconsistent in their willingness to eat the silage, K-State veterinarian Brian Lubbers said it is important for producers to take and store samples as they work through the feed so when they go off feed they can pull the appropriate sample to test.
“There are microclimates within a silage pit, and so take the samples as you are feeding so that you have a representative sample to help you figure out what is actually causing them to stop eating the silage,” Lubbers said.