With our first cool days of the fall season, it’s important for livestock owners to start considering winter forage needs of their livestock. Some people may choose to plant cool-season forages to help meet nutritional needs during our cold season, but many rely on hay or other forms of stored forage. There are a few things to consider when determining winter forage needs for your livestock, from forage quality to intake. For today’s example, we’ll be talking about cattle, but the premise is the same for horses, small ruminants, and other grazing stock. If you need help finding data such as voluntary intake and nutritional requirements, contact us for assistance.
First and foremost, send in a forage sample to ensure you are feeding a quality hay that can meet the nutritional needs of your animals. Forage quality is essential, since some species (mainly cattle) can consume a higher quantity of good quality forage when compared to poor quality forage. Furthermore, better quality forage is more apt to meet nutritional needs and result in less supplemental feeding than poor quality forage. A forage test provides the data you need in order to do the following calculations.
Each species has a specific voluntary intake- or an amount of feed and hay we expect them to consume in a day. For most grazing livestock, that number varies between 1.5-3% of their body weight. For cattle, we will assume a daily intake of 2.5% of their body weight. If you have 15 mature brood cows at 1,200lbs, 1 bull at 2,000lbs, and 5 weaned replacement heifers at 500lbs, we expect the following: (1,200lbs X 2.5lbs/100lb BW x 15 cows) = 450lbs for the cows; (2000lbs x 2.5lbs/100lbs BW x 1 bull) = 50lbs for the bull; and (500lbs x 2.5lbs/100lbs x 5) = 62.5lbs for the calves. In total, we expect to feed 562.5lbs of dry hay (0% moisture or dry matter basis) per day.
This calculation is on a dry matter basis, which basically removes all of the water from the forage. Hay is typically around 85% dry matter, meaning 15% of the weight of the hay is coming from water. In this case, when we account for the water, our 562.5lbs dry matter hay is actually 662lbs of hay as we feed it.
The next thing we can do is determine our feeding period. If we start feeding hay around Thanksgiving and expect we can stop in April or so, we have around a 120-day feeding period. If we multiply 120 days by our daily as-fed feeding rate, 662lbs, we need 79,440lbs of hay to feed through the winter. To account for storage and feeding loss (assuming barn stored and fed with a hay ring), we can increase this amount by 15%, giving us a total of 91,356lbs.
Now that we’ve calculated the amount of hay we need, let’s put it into more applied terms. We will need approximately 92 round bales at 1,000lbs each to supply enough forage to our cattle through the winter. It’s important to note that the only way to know the weight of your round bales is to weigh them—many times people overestimate how much they weight and wind up short on hay in the winter months.
If you need assistance calculating hay needs for your livestock, regardless of species, feel free to contact us at uge3181@uga.edu or 706-359-3233.
