Tips for Corn Grazing
Rikki Wilson, AAg, Livestock and Feed Extension Specialist, Humboldt
As we move into the winter-feeding period and cows are turned out into extensive feeding systems like corn grazing, there are a few tips to keep in mind to ensure you are making the most of the feed you have and are using it in the most appropriate way.
Limit what the cows have access to
A general rule is to allow cattle access to no more than three to four days’ worth of feed at a time. Because cows will generally eat the cobs first, allowing them access to more than this amount of feed may result in instances of ruminal acidosis. A mature cow will eat two to 2.5 per cent of its body weight per day or 28 to 35 pounds on a dry matter basis.
There is a common misconception that the less you move your cattle when corn grazing, the more money you will save on labour and fuel. However, a University of Saskatchewan study from 2015 to 2016 found that the average cost of moving cows every three days versus every nine days was $1.60 and $1.84 respectively. This $0.24 per head per day difference was seen because those cattle moved more often had better forage use and left less plant biomass behind than the cattle moved less often, resulting in more cows fed per acre.
Supplement when necessary
In some cases, supplementing with additional protein may be necessary depending on the animal’s stage of production and the nutritional value of the whole plant. Standing corn may not meet the protein requirements of a cow in late gestation, resulting in the need for an additional protein source through something like a cereal grain, canola meal or protein pellet. Providing a source of low-quality hay or roughage may also be an option if the energy value of the standing corn is high enough. A supplemental roughage will aid in slowing down rumen function to allow for better digestion of the cobs and will reduce the animal’s risk of acidosis.
Know what you are working with
Feed testing prior to turning cattle out to graze is the best way to determine whether nutritional needs will be met without supplementing. A feed test will also give you an idea as to what type of mineral should be used. In some cases, a 2:1 mineral is enough to meet requirements; however, in other instances it may be necessary to bring in supplemental limestone to bring that calcium to phosphorous ratio back into balance. Since corn is typically grazed by pregnant cows and heifers, trace minerals like copper, manganese and zinc are important to have in the diet as well.
Your regional livestock and feed extension specialist can help with the process of getting corn stocks tested and coming up with a feeding plan to ensure your herd’s nutritional requirements are being met. For more information on corn grazing or for other livestock production related questions, contact your regional livestock and feed extension specialist or call the Agriculture Knowledge Centre at 1-866-457-2377.