Supplementing Beef Cows, What Do They Need

Unfortunately we find ourselves in a real bind this year. With no rain there is very little pasture, hay production is almost nonexistent, and beef cattle prices are down significantly.

Daily energy intake is the primary limiting factor affecting beef cattle performance on forage diets like coastal hay or pasture or even native grasses. This energy intake can be further limited when forages supply an inadequate amount of crude protein. The reason for this is that the amount of crude protein in the cow’s diet needs to be in balance with the energy content. This is usually expressed as a ratio of 6 parts energy to 1 part protein. For instance, hay with 60% total digestible nutrients or TDN would need a protein content of 10% to be in balance and allow the microbes in the rumen of the cow to properly digest all the energy and also have enough energy to digest all the protein. The problem is that we allow pastures and hay fields to get too mature so that they have less protein and energy as a percent of the total. It is not unusual for coastal hay to test 45% TDN and have a 5% crude protein (CP). This is a ratio of 9 TDN:1 CP which is way out of line. This kind of ratio has been researched to limit dry matter intake to just 1.6% of body weight(BW) when it should be above 2% of BW. When the crude protein of a forage falls below about 8% the dry matter intake of cattle declines rapidly. This decline is attributed to a loss of rumen microbes as they die for lack of protein. This is why feeding a high quality protein supplement will improve both the protein and the energy status of cattle. This is simply because the rumen microbes can now work better so that they improve the forage digestibility for the cow and when this happens the cow can now take in more forage so that forage intake increases. I said earlier that at 5% CP, forage intake is limited to about 1.6% of the cow’s BW. When the forage is improved to 8% CP or if a high CP supplement (25% or greater) is added with the forage then forage intake increases to 2.3% of BW. This is a 44% increase in forage intake or nearly half again more. This means that she will eat more of the lesser quality pasture or hay and lose less weight in the winter because as she eats more forage she gets more energy. If you remember what I first said was that energy is the limiting factor for cow performance on forage diets. Most of the time we say it is protein and we will usually buy hay based on protein but what we really mean is we want the higher protein in order to balance the energy. Again that ratio needs to be about 6 TDN : 1 CP or you will find that the cattle will perform poorly even though you have plenty of feed.

Now for some rules of thumb you may want to go by for supplementing cows. First if you have plenty of pasture (I doubt you do this year) but you know it is low quality then feed a protein supplement but no hay. This will help them digest the low quality forage. Second, remember cattle are designed to lose up to 15% of their BW in winter we just don’t like to see them do it. Force them to eat the low quality stuff as long as possible. Third when you start feeding hay you can’t quit. This is mainly because they don’t want to if you will feed them and secondly the higher energy in the better hay puts the rumen on a new level and so they really can’t go back to the pasture as easily. Fourth know what your hay tests. You may need to add a protein supplement to your hay if it is not balanced to be 6 TDN: 1 CP. Fifth stay away from energy supplements as long as you can since they are the most costly. This may not be possible if your hay and pasture are really poor quality and/or you don’t have much forage which is definitely the case this year.

What Do Deer Eat?

This has got to be one of the worst Falls I have ever seen. It is so dry and hot for fall weather and all of this has taken a toll on plant growth. Just look for an acorn crop - there isn’t much of one and on top of that most of the browse, forbs and grass deer might eat is dry. Anyway with all the problems landowners do need to know what deer eat to manage for this important resource.
One of the best publications for plant identification in the Cross Timbers I own is “White-Tailed Deer: Their Foods and Management in the Cross Timbers.” This is a publication of the Samuel Roberts Noble Foundation and is probably the most valuable book anyone interested in deer management could have, but it also makes an excellent reference because of its color photos of area plants. In the front of this publication is an appendix that lists the species composition of deer diets from Summer 1985 to Spring 1987. This chart shows hundreds of plants and basically how much of them a deer eats.
The top plants for the fall and winter may surprise you at least they did me. Bromes and tall fescue can make up to 25% of the diet composition. These are the green grasses that you see growing mostly under trees and resemble wheat or oats. Two to eight percent of the fall diet can be made up of honey locust but not necessarily the plant mostly the seed pods. Osage orange or Bois d’Arc (horse apple) trees can make up 17% of the diet mostly for their leaves. Deciduous oak trees like post, red, blackjack all are very valuable in a deer diet most of the year but acorns can account for a significant percentage in the fall if the acorn crop is good. In 1985 42% of the diet was acorns but in 1986 only 1.5% was acorns, owing I’m sure to a bad acorn crop. Coralberry is a significant plant for the deer diet in the fall and winter of every year. As much as 31% of the deer diet in the winter of ‘86 was composed of coralberry. What is coralberry? Around here we normally call it buckbrush and it is a shrubby plant 3 - 6 feet in height found in woody to open sites. It produces a small fruit but for deer all the plant parts are like t-bone steak. Here’s one you may not ever guess that deer eat, mushrooms. Almost every fall deer diets will consist of 4-5% mushrooms and I guess they don’t have a problem with the poisonous kind like we do.
Lastly let me add that small grains (wheat, oats, rye, etc.) can make up a significant portion of deer diets especially in the winter. In 1985 these were 21.5% of deer diets but almost 0 in 1986 when other plants were available. I am constantly amazed at deer hunters and landowners who want to provide small grains as a source of nutrition in deer diets in hopes of having bigger bucks and does, especially trophy bucks. If you want to produce trophy deer, extensive deer habitat management is almost always more important and more efficient than intensive management i.e. planting small grains and providing feeders. Plus the management of deer habitat means that they get the nutrition earlier in the year when they need it to produce the big antlers and develop good body condition.