August 17, 2015

(Dan) Hi there folks, welcome to Doc Talk, I am Dr. Dan Thomson. I’m glad that you joined us today, it’s going to be a great show. Our guest is the Section Leader for Veterinary Toxicology from Iowa State University’s College of Veterinary Medicine, Dr. Steve Ensley. And we’re going to talk about ergot toxicity and things that can be associated with that whether it’s cattle or horses. Stay tuned and enjoy the show.

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(Dan) Steve, welcome to the show. (Steve) Thanks for having me here. One of the things that we’d to talk about is ergot toxicity. This year has been particularly problematic in the Midwest in general with ergot. It’s a fungus that will grow on grasses and produces a chemical similar to what fescue does. So, this year, not only have we had some of the issues with fescue grass that we normally see, but when this fungus… a second fungus grows on the seeds, and this produces the same similar toxin then those effects become additives. So, not only do we have issues with fescue that we normally do but we’ll also double the dose basically, with some of these ergot infestations that we have seen. Because of the cool, wet spring. In the Midwest last year we had a lot of rain and it looks like the drought was over. It rained until the end of May. It quit at the end of May and then the rain was very spotty then from then on. That cool, wet, early part of the year was ideal for this claviceps purpurea fungus that grows on there. And so it infected a lot of the grasses that we make hays out of, besides the grasses that we graze and so a lot of the animals that may be on fescue on the summertime, get to eat hay in the fall and winter then that is not infected. This year we didn’t get that opportunity because we had this ergot that infected the grass and we’re still seeing issues right now with that. (Dan) So, what type of grasses are we most commonly seeing it in? (Steve) Well normally, we can see it in any of the grasses that we’ve seen it anywhere from timothy hay to brome hay, any of the grasses are… anything with a seed head is going to be susceptible to this fungus when the conditions are… when the environmental conditions are right. And so those grasses that don’t produce the endophyte like fescue does will not be as bad as fescue but we have a lot of fescue in our pastures, a lot of fescue in our hay meadows and so when we have the fescue alkaloid, the ergot veiling, in addition to these ergot alkaloids from ergot, it has been a significant issue. (Dan) So wet spring, followed by a drought is kind of the perfect…. (Steve) Perfect storm for that ergot. That is exactly what it likes. And this year, we normally have ergot, we see ergot in our grasses, but not to the extent that we’ve seen this year, with the numbers of ergot infestations are, you know, very high. We’ve done some survey work, probing bales to see what concentrations these ergots have been and they’re, they’ve been extremely high. (Dan) And what are some of the limits then when we are talking about ergot infestations? (Steve) Some of the same things that we talk about when cattle are grazing fescue, the heat intolerance in the summer time. They get fat necrosis, or have the potential to do that. It is vasoconstrictive so it can affect the ends of the ears, tail tips and hooves. Those are summertime problems. In the wintertime what we see then is that vasoconstriction again, causing lameness, intermittent lameness issues that are related to the blood supply to the hoof. So we can have any where from intermittent lameness all the way to hoof necrosis, where the animal actually loses the hoof. We’ve seen some of that this year in cattle. Horses are particularly sensitive. They are even more sensitive than cattle. (Dan) Let’s take a break and let’s come back and touch more on the equine side of things. You’re watching Doc Talk and we’re glad that you joined us.

(Dan) Hi there folks, welcome back to Doc Talk, I’m Dr. Dan Thomson here with Dr. Steve Ensley. And Steve you are the Section Leader of Toxicology at Iowa State’s College of Veterinary Medicine which you know, you guys see a lot of cases and have a tremendous history for veterinary diagnostics and veterinary toxicology and glad to have you on the show. And ergots is one of those that, whether it’s fescue or whatever, we have… it’s been around since Moby Dick was a minnow. (Steve) Right. A lot of the… actually the French Revolution was blamed on ergot ingestion, the a lot of historical events, even the witch craft trials in Salem were blamed on ergot ingestion. People get hallucinogenic when you consume those. So ergot, as long as there has been greens and people have been consuming those, there’s been issues with ergots. (Dan) Yeah, we don’t want people going out and eating fescue. (Steve) No. No. Well a lot of… we have wheat, the small grain, the ryes, the barleys, the wheats get ergotized and historically they made bread out of those- had the chemical in there and then people ingest it and actually we see the same things in animals that we do see in humans. (Dan) The heat intolerance was the one that was the classic sign for me when I would have cattle come into feed yards or come in off of pasture, and it would be 80 degrees and all the other cattle are doing fine and here’s a pen that open mouth breathing and can’t stomach it. (Steve) Exactly. The fescue, the endophyte infected fescue grass has gradually moved across the U.S. We didn’t have, ten years ago we didn’t have problems in Iowa with it. Now it’s a common grass in our fields and so, and it’s moving north all the time. It’s a very hardy, well adapted grass, does fine. Except the animals, when the endophyte is in a high enough concentration, the animals just can not tolerate. You know, the dose they get when they have to ingest that every day. Horses particularly are a species that’s very sensitive, even more sensitive than cattle. Probably the most sensitive to the ergots that we see in the grasses and hays. And one of the problems that we see this time of year is prolonged gestation. And if a mare is on… if a pregnant mare is on the ergotized grasses or fescue grasses even, they won’t fowl, they’ll maintain the foal, their foaling date… they’ll exceed their foaling date by weeks sometimes. And then when they do foal, they’ve got an oversized fetus, the placenta is edematous and they also become very agalactic with that. So if they do manage to have a foal alive you know the agalactia issue can be as serious as anything else. That we see. (Dan) So when we talk about earlier in the gestation period it can cause an abortion issues. (Steve) It’s potential for abortion issues, especially because it’s heat related. Animals are being bred when it’s hot and they can’t maintain normal temperatures, so we do feel like we see abortion issues and have this last year because of the ergotized greens. (Dan) So, take home message is, if you’re going to… during the drought situation, make sure you get your hay tested. (Steve) Right. This year particularly it has been an issue, you need to know the status especially your grasses that you graze, you know, we need to be able to get animals off of those periodically if we can to be able to manage those and so testing is one of the strategies that we’ve used. (Dan) Good. When we come back from the break folks, we’re going to continue on with Dr. Steve Ensley. He’s a world of knowledge for us on veterinary toxicology. Tickled to have him here. And we will see you here in just a minute.

(Dan) Folks, welcome back to Doc Talk. Dr. Dan Thomson here with Dr. Steve Ensley and Steve during the break we were talking a little bit about cows and gestation and calving and things to that. We talked about the horses and prolonging gestation. What are some of your recommendations on cows? (Steve) What we’ve seen this year is because of the high ergot alkaloid in our grasses that cattle are grazing we saw some abortions we felt like were related to that- cows ingesting the ergot. Inability to regulate their body temperatures, and so on hot days they don’t want to… they don’t want to move, they are trying to look for shade, so they don’t want to breed. And the bull is affected as well. The bulls suffer from the same things that cows will. (Dan) Right. (Steve) So we did see some cases where we had high open numbers when the cows were pregnancy tested this fall and we feel like those were related to some of the ergot issues that we’ve seen. (Dan) And then when you have them on the hay and they’re gestating there’s points in time when they can tolerate it but then you have to get them off? (Steve) Right. They can… normally we like to have them off, if they’ve got to graze fescue in the summer time, get them on hay in the fall and the winter that doesn’t have any ergot or fescue in there. But if we don’t have any alternative and we have to feed it we have been feeding that to late gestation cows but trying to make sure we get them off of that at least a month before calving and hopefully that will be enough time. These ergot peptides are very tightly bound on the vessel surface and make them constrict and so the bad thing about exposure is it can take a long time to wash out and get rid of the compound totally. So they can tolerate it for a while, but late… if it’s calving season right now we want to get them off because we are worried about the agalactiae and other issues associated with it. (Dan) And we have an agalactia for non-veterinarians? (Steve) No milk. So they have no milk. Normally we see, you know, cows that look, the udder looks fine, the calves are born, but there is no milk or very little milk and they don’t get… that affects the amount of colostrum also that they are able to produce so…. (Dan) Big time. (Steve) Big time… big time problem this year has been particularly problematic for us. (Dan) Agroceosis, from agalactia, from the cow to the calf. And when we see them in the feedlot, we see those weaned calves come in the feed yard, you know, it does take a while. It seems as though they get over faster on a grain diet. (Steve) Right. (Dan) The washout period is shorter if we put those animals on… switch them over to a two ration or three ration, but it’s still going to take quite a while. (Steve) Yeah. It’s a… we’ve looked at a lot of intervention strategies when we get animals in, you know, to get them off of there. What do we do to… For horses we do have a compound, domperidone, that you can treat a mare with that will help, will alleviate the negative effects of these ergots, but it’s not cost effective in cattle. You now it’s just… so we are limited about what strategies we can do to try to limit the impact. (Dan) Well, and we also have to keep withdrawal times and consumption things in mind that we don’t have to with a companion animal. (Steve) Right. That’s a big issue. A safe food supply is one of the things that we’re all very interested in and ergot can complicate that a lot. (Dan) You bet. Well, we’re going to take a break. And when we come back, we’re going to wrap up our discussion today with Dr. Steve Ensley from Iowa State University talking about ergot toxicity. Stay tuned.

(Dan) Folks, welcome back to Doc Talk, Dr. Dan Thomson here with the Section Leader for Veterinary Toxicology, Dr. Steve Ensley and he is a on staff at Iowa State University’s College of Veterinary Medicine and we’re talking about ergot toxicity and that so one of the things we decided we better talk to them about testing. And you do that every day in your lab. (Steve) Exactly that is kind of our key. That’s our part of the diagnostic process is how do we quantitate what the exposure is and try to determine risks so… you can… we can test the forages or grasses for these different ergot peptides. So what we look for in pasture grass if you want to click seed heads or grass in general and take some swaths, we like to get about a pound of the material. And then we process that, try to make it homogenous then we analyze that for these different alkaloids that are in there. But… so grass samples you can collect because we do some of that to see how much fescue is there and how much of this alkaloid is in there because the fescue grass actually… it’s a defense mechanism, so when it’s drought stressed and it’s not getting the water it needs the alkaloid concentration will go up in the grass seed, in the grass itself. And when it goes to seed is when it’s particularly problematic. So you want to prevent… if you’ve got fescue grass and you’re grazing it in the summertime, prevent it from going to seed because the concentration is ten times higher in the seed than it is in the rest of the plant. (Dan) And that is the reason why you’ll see some people out there on their paddocks mowing it before it seeds, if it heads out, or before it heads out. (Steve) And then once you make hay you know, this year in particular, what we like to do, is we like to sample the bale. But we want to make sure if you are going to probe the bale, the sample, that you go in from the side of the bale not the cut face, not the end of the core. (Dan) Not the core. (Steve) Because we want to get a cross section of the seed heads and as much grass as we can through the whole bale and when we go through the side and make a probe there we just get one section of the grass not a good distribution. (Dan) So do you go all the way across? (Steve) We try. Depends on the size of the probe. You know, we will collect as many probe samples as we can, mix that sample… have people try to carry a five gallon bucket, probe as many bales as they can put that into a five gallon bucket, mix that up and then send about a pound of that to me to analyze. We get a good representative sample and feel like we can give you good information on your risk associated with those bales. (Dan) How many bales should they… or just get that five gallon bucket full? (Steve) Yeah, if you get that five gallon bucket full, sample as many as you can you know the more hay you have, the more samples we get, the more random distribution the biostatisticians love that. The more samples the better. And we love that too. So take as many as you can. Take two five gallon buckets if you want to mix those up, grab a subsample out of that and that’s what we like to test. (Dan) OK and on the grass samples in the pasture is there any place in the field that you shouldn’t test? I remember we used to throw a Frisbee and whenever it landed was the random place. (Steve) Exactly. What I usually tell people to try to do is draw a diagonal line somewhere across the pasture, and walk across that line and every 10 steps take a sample and collect it. Because what we are trying to do is get as random of a sample as we can from there. So, Frisbee method, five gallon bucket method, I think any of those are all acceptable. (Dan) Well, thanks a million for being on the show today. It’s always good information and fun to have you here. (Steve) You bet. Anytime. I love to talk about veterinary toxicology. (Dan) Well, we’re going to have you back. (Steve) All right, sounds good. (Dan) And thank you for watching today’s show. Remember, always work with your local veterinarian and if you want to find out more about what we do on Doc Talk you can find us on the web at www.doctalktv.com. I’m Dr. Dan Thomson here from the College of Veterinarian Medicine at Kansas State University. Thanks for watching the show and I’ll see you down the road.

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