With forage already scarce, Extension experts advise ranchers to find out what their hay is missing.
Tom Troxel, associate head of animal science for the University of Arkansas System Division of Agriculture, said hay produced in drought conditions is often short of protein and needs to be supplemented. “Unless you have it tested, though, you don’t know for sure,” Troxel told Ozarks Farm & Neighbor. “One thing we have seen with poor quality hay is tremendous variability… One lot of hay might test very high; another group of hay might test very low.”
Troxel said there’s very little forage available in Arkansas. “The pastures are very bare, and many producers have had to cull their herds,” he said. “The reports that we get from our Market News are that the culling is up about 5 percent, and that’s quite a bit. Right now the hay situation is dismal; the first cutting of hay, which occurred back in May, was about 50 percent of normal on average – 40-60 percent, and many producers have been feeding hay since late June. So going into the wintertime, there’s just no hay to be found.”
As a result, many producers are sourcing hay from out-of-state, which Troxel said makes it all the more important to have that hay tested. “If it’s very good quality hay you may not have to feed any extra protein or energy, but more likely than not you’ll have to add some sort of extra protein or energy to that hay because if you don’t, the cows won’t get the nutrients that they need in the amounts that they need them in, and then cattle performance will suffer,” he said.
There are other health problems associated with cattle fed drought-damaged hay. Troxel said cattle will also need to be supplemented with Vitamin A. “Any time that you have bleached out hay that’s not green, Vitamin A is very important,” he said. “We generally recommend a Vitamin A, E and D shot for your cattle; that’s generally good for about three months. Follow the label instructions; there’s usually a withdrawal time with your Vitamin A shot so if you plan to cull the cows, make sure you follow the withdrawal time instructions.”
Arkansas has also experienced several cattle deaths this summer from prussic acid poisoning. The cyanide compound is found in several types of grasses when those grasses are stressed by drought; those belonging to the sorghum category, like Johnsongrass, are most likely to contain potentially toxic levels. Troxel said, “When drought stressed Johnsongrass gets a little rain it will pop up a nice, green blade of grass, and that will have the prussic acid in it.” He advised producers to keep cattle out of fields with new growth less than 24 inches high, and don’t allow them to graze drought-damaged plants in any form within four days following a good rain.
Dona Goede, southwest region livestock specialist at the University of Missouri Extension Service office in Cedar County, added forage labs do not commonly test for prussic acid. “People just need to be careful about using things that have Johnsongrass in them,” she told OFN. One thing they can test for, though, is nitrates, which can cause reproduction problems in cattle. “Even if the nitrates are just moderately high, you may not see the problem with it until you see that several of your cattle are open this fall because of high nitrates,” she said.
Once you know how high the nitrates are in your forage, you can blend it with low-nitrate forage or reserve it for non-pregnant animals. The heat is likely to cause reproductive problems anyway, but the presence of nitrates in feed will compound the problem. “A lot of people trying to breed in June and July are going to find many cows open, because not only do the bulls not want to go out and breed cows, but those very young embryos and fetuses cannot tolerate the high temperatures,” Goede said.
If you’re feeding hay that was tested several months prior, it needs to be retested for quality.
Corn silage, too, presents a nitrate concern. “They really need to test it after it goes through the ensiling process,” Goede said. “If it does test slightly high, corn silage is (a feedstuff) we can mix with something that does not have nitrates in it, so it may be safe to feed. It’s not a waste just because it has nitrates, but we need to know what the level is so we can safely feed it.”
