Using a hay bale to supplement your cattle is a tried-and-true method that many producers use. It is reasonably priced compared to other feedstuffs, though the quality can vary depending on many factors.
While using a hay bale, many people tend to look at the upfront cost. While this may be good initially, it is not always best to be the only way. You will want to examine how much that particular will cost per unit of energy or protein.
Like with other feedstuffs, it is always a good idea to break down the price into simple units to compare apples to apples. Though a hay bale may look like a good deal initially, it may not be. Once you have broken down the price into those units, you will find it will cost you more.