If you can purchase distillers grains lower than corn price and get them on your operation at equal to corn price or better, distilllers would be a good buy. Current recommendations is to feed no more than 33 percent of diet on a dry matter basis (DM). This will certainly meet the protein needs, as feeding approximately 20 percent will meet that need. Distillers grains normally run approximately 30 percent protein on a DM basis. Normally, you should be able to purchase distillers relative to corn price, and therefore it will be a much cheaper source of protein for the steer than soybean meal. Steers require degradable intake protein (protein used in rumen for microbes to grow) and then bypass protein (UIP or undegradable intake protein) to help meet the steer's protein requirements. The steers protein needs, such as metabolizable protein or MP, are met with the sum of microbes that are produced in the rumen and the bypass protein. The reason for bringing this up is that feeds vary in the type of DIP or UIP protein amounts. Urea is a good feed source for rumen microbes to make protein for feedlot cattle because their diets generally need more DIP, more so than UIP.
Dry matter is maximized when the feedlot ration is formulated to contain between 68 and 75 percent dry matter. Adding enough wet distillers grain to the diet to go under 68 percent total dry matter may depress feed intake.
Another concern is total sulfur intake. When sulfur levels of feedlot diets exceed .40 percent, sudden death, or "brainers" may result. Analysis of distillers grain with solubles have reported values ranging from .4 to 1.2 percent and greater. High levels of sulfur will limit inclusion rates of distiller grains in most feedlot diets.
If you have 13 percent or more crude protein in the diet, you will meet the steers overall requirements for both DIP and UIP in almost all situations. If you feed high levels of distillers grains, you will easily meet all the protein needs for the steer.
Important considerations are whether you have access to the wet byproducts or dry byproduct, how much you can feed at one time, and shelf-life/storage issues for the wet feeds. The percentage of the diet listed above is all on a DM basis. If you have access to the wet feed, cattle perform very well on this, but you have to feed extra -- on an as-fed basis -- to account for the moisture when you are weighing up the feeds. This is similar to silage, which has approximately 35 percent DM or 65 percent water, where you have to weigh out extra to account for the extra water when added to dry corn diets.
The last thing is to ensure that you have calcium in the diet and other ingredients if you get a supplement. The diet you have here is relatively high in P and essentially zero percent calcium. Limestone is cheap and could be provided in a supplement, especially if you want to add other ingredients to a supplement. The bare essentials,which should all be relatively cheap, are urea if you are not adding protein with soybean meal, distillers grains, or gluten feed; limestone for calcium; vitamins A and E,often in a vitamin ADE package; trace minerals if you want appropriate balance, and any additives such as Rumensin (an ionophore that helps with managing high grain diets and improves efficiency) and Tylan (antibiotic for liver abscesses) at appropriate, or legal, amounts. Be sure that you have little to no phosphorus as it is expensive and useless in a feedlot situation with grain or grain and byproducts.
Use step-up diets to adapt calves to changes in the amount of ingredients in each ration.
