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Grass, ergot, mouse turds, caution – Audio

Dan Undersander
Extension Forage Agronomist
Department of Agronomy
UW-Madison College of Agricultural and Life Sciences
Phone (608) 263-5070(608) 262-1390

Dan Undersander fills us in on what to look for before feeding hay to your animals this winter.

3:04 – Total Time

0:15 – Introduction to ergot
0:39 – What ergot does
1:05 – What to look for in grass hay
1:50 – Feed carefully if at all
2:36 – Where to get help
2:54 – Lead out


Sevie Kenyon: Dan, what is this fungus?

 Dan Undersander: There is a fungus called ergot, e-r-g-o-t, that grows actually on grasses. Orchard grasses, brome, timothy, even blue grass. This was an especially bad year for the fungus, and then also because it was wet; in some regions we were late getting into the fields to harvest them so we had more grass heads than usual.

 Sevie Kenyon: Can you tell us what this ergot is?

 Dan Undersander: What it does is it grows on the plant, and then it makes a mat of Massilia, or fungal fibers, that actually looks like…well I’m going to say mouse turd, and it grows right in the seed head. Ergot contains alkaloids, it does affect then all of our animals that would eat the grass—sheep, cattle, horses.

Sevie Kenyon: Someone who’s buying hay Dan, what do they look for, how do they avoid this?

 Dan Undersander: First look for seed heads in the hay. If you don’t see any seed heads, you don’t have the fungus. Secondly, if you do have seed heads, in brome, timothy, orchard grass, tall fescue, blue grass hay that you might be buying, any of them; look to see if you have what looks like little mouse turds in that hay. And if you have those then that ergot is present, and then you should be very cautious in feeding that to your animals. If you buy hay without the seed heads, if you get it from here- south you’ve got less issue with it this year, but from here- north any grass hay that is bought with seed heads should be checked carefully.

 Sevie Kenyon: And what do you mean by “careful feeding it”?

 Dan Undersander: I would feed less than ten percent of it in a ration. If, and that’s where we run into problems because often times for horses, and even cattle over winter, this could be their primary feed stuff, and then they could run into problems. What does it cause? It could cause lameness in the animals, because it causes vassal constrictions. If it’s severe enough it’ll, it’s cumulative, so three or four weeks in, and feeding this, you might see the ears fall off, those sorts of things. And then if it is at high enough concentrations, it will actually kill the animal. And particularly again it becomes worse in cold weather because that’s when the blood flow is more important.

 Sevie Kenyon: And Dan, where can they turn for some help?

 Dan Undersander: Well the main thing I would say would be to contact your county agent, and have him look at the sample. And then we do have a plant pathology lab here on the University of Madison campus that can look at the sample and tell if it is these ergot massilia masses.

 Sevie Kenyon: We’ve been visiting with Dan Undersander, Department of Agronomy, University of Wisconsin Extension and the College of Agricultural and Life Sciences, Madison, Wisconsin, and I am Sevie Kenyon.