December 2017
Feeding Facts

Evaluating the Hay vs. Feed Question

Especially in years like this one, knowing the nutritional value of your cut forage is critical to making the most economical feed decisions.

Forages are a main component in feeding all ruminants and highly important in horses’ diet. Cattle, sheep, goats and horses all have a need for some long-stem-type fiber in their diets. The most common place to find that is the grasses they graze or the hay provided to them. So, it quickly becomes clear that we need to do a good job growing and storing grass and hay. We also need to have it tested so we know what we have and can supply our livestock with what they need. We want to feed the hay to minimize waste, because, when you put a pencil to it, hays and grasses really are expensive.

This is really not the place to go into growing forages but keep in mind that proper soil fertility is a key to growing quality forages and where it all starts. Hays and grasses from well-kept soils will add value to your feeding program and cut supplemental feed costs. Your local Quality Co-op folks can help you.

Harvesting forages properly is also important. When we have a wet year like this one, timely harvesting becomes difficult and often the grasses get too mature before we can get them stored. This will mean that the hay will likely be lower in protein and energy, and higher in fiber. Most likely, it will not meet our livestock’s needs during times when they are producing more.

When the weather does not cooperate, it becomes difficult to get the hay put up correctly. When hay dries too long, you will get a much higher percentage of shattered leaves lost. The leaves are where most of the needed nutrients are located. You will get up to 20 percent of shattered leaves in good condition. If the hay stays too long in the sun before it is stored, you can see 50 or even 75 percent of the shattered leaves lost before it reaches the baler. When you take that into account, the hay will contain, in a good year, about 75 percent of the protein and energy the grass had before it was cut.

Now, when you get the hay stored in the barn, whether you cut it yourself or you bought it, get it tested. Extension personnel have told us this for years and they were correct. You need to know what you are feeding. The hay might meet all your livestock’s needs and you won’t have to spend additional money on supplements. However, you need to know either way. This year I have seen a good number of hay samples and very few of them were good. Most were deficient in protein and energy, and had more fiber than needed.

When you have the hay sampled, you will get back lots of important information, but there are a few numbers that will likely mean more for the average producer than the others.

We will talk about protein first as it is one of the more important ones. This year, the average of all the samples I have seen is 8.7 percent protein. For grass hay, this is OK, but not great.

The second number most producers will look at is TDN or total digestible nutrients. This is a measure of the energy stored in the feed or hay. It is as important as protein and a number we all need to know. This year’s average on hay samples has been 54 percent. That is poor quality. A chart I use shows that anything below 54 should be used for mulch.

Why is the TDN that low? Most likely the samples I’ve seen were cut late and the grass was more mature than it should have been. Had it been harvested earlier in the growth cycle of the plant, the protein and TDN would, most likely, have been higher, but with the rain we had it probably wasn’t possible.

There are many other numbers on the forage reports producers need to know. ADF or acid detergent fiber and NDF or neutral detergent fiber are also important. They all will tell a story about digestibility, energy levels and just how much of these forages the animals can consume.

ADF indicates just how digestible the fiber is. The lower the number the more digestible the forage is. Hopefully, your sample will be 30 to low-40 percent. Our average hay samples this year were 43, again bordering on OK to poor. Over 46 would be really poor.

NDF indicates how much an animal can consume. Again, a lower number is better. NDF values in the 40-percent range would be excellent, in the 50-percent range good and over 60 percent starts to seriously limit how much an animal can eat. Our average hay samples this year were 69. That will limit how much the animals will voluntarily eat.

When we take into account the fact that the hay is fairly low in protein and energy, and now the animal can’t consume enough of it, it means that to maintain our herds we are likely to have to provide a good bit of supplementation.

When you look at the cost of hay, often feed is a more economical option. For instance, if a 900-pound bale of this year’s average hay cost $30, each pound of actual TDN would cost 6.1 cents. If a ton of decent (say 13 percent protein and 65 TDN) feed costs $200, the actual cost of a pound of TDN would be 6.5 cents; more, but not by much. If you factor in the waste you get when feeding hay, your herd’s energy needs can be met more economically with a quality feed.

The animals will always need some long-stem fiber, so some hay is absolutely needed. Keep in mind that hay is expensive and you need to have it tested. That helps you make a good business decision on how much hay is needed and when and where you need to buy feed to fill in the holes the forage program leaves in meeting your livestock’s needs.

In the long run, your animals will do better and so will your bank account.


Jimmy Parker is AFC’s animal nutritionist.