You may recall that several months ago, I had been encouraging everyone to participate in the statewide forage testing program being conducted by the OSU Extension Beef Team. While we only had a couple of samples submitted by producers in Wayne County, we collected 180 samples from around the state.
A summary of total digestible nutrients (TDN) and crude protein (CP) values from those samples was published in the Sept. 10 edition of the OSU Beef Team Newsletter (https://beef.osu.edu). While we expected to see a lot of variability among the samples, we were concerned with the overall low-nutrient quality of the hay. This isn’t a reflection of a producer’s ability to harvest quality hay, but more a testament to the difficult growing and harvest conditions we saw through the late spring into the early summer.
The grass hay sampled averaged 49.28% TDN (range of 25.3% to 59%) and 9.75% CP (range of 5.83% to 17.51%). The mixed grass-legume hay was marginally better with an average TDN of 51.71% (range of 35.1% to 69.6%) and CP average of 10.06% (range of 5.98% to 21.7%).
Although the average nutrient quality values indicate that acceptable hay was produced, the extreme range between the lowest quality and highest quality emphasizes the need for a forage test. I assisted with the analysis of these samples, and while there were visual differences that could help sort out the lower-quality hay, many of the samples looked good to the eye but failed the scientific analysis.
What do these results tell us in terms of feeding our livestock? First, we need to look at what our animals require. I am going to exclude our dairy brethren from this discussion, as there may have been one or two samples that they would consider feeding. To keep it simple and shorten the discussion, let’s consider a 150-pound ewe and a 1,400-pound cow.
A ewe that isn’t lactating or pregnant will eat about 2.6 pounds of dry matter (DM) each day. From that DM intake, she will need to consume 1.5 pounds TDN and 0.25 pounds CP. Considering the amount she can eat each day (2.6 pounds DM), the average grass and mixed grass hay we test will meet her needs for CP, but she can not consume enough to meet her TDN needs on the hay alone. As she enters the last four weeks of gestation, we would expect her to eat 4.2 pounds of DM each day and need 2.8 pounds of TDN and 0.47 pounds CP. She would not be able to eat enough of either type of hay to satisfy her requirements and this difference only increases once she enters lactation.
If we look at the needs of a 1,400-pound cow that is in her second trimester of gestation, she will eat about 23.1 pounds of DM that will need to contain 11.6 pounds TDN and 1.73 pounds of CP. Both the average grass hay and mixed grass hay will meet her TDN and CP requirements, but as she enters her last trimester, she will not be able to eat enough to meet her increasing requirements. All of this signals that whether we are talking about sheep or cattle, the average hay that was sampled will not fulfill all their nutritional requirements when their requirements are the lowest. This means that some additional supplementation will be required, usually provided by grains. The proportion of grain supplementation will also need to be increased as she approaches the later stages of gestation and on into lactation.
Those producers who found themselves with average or below average hay will need to target their supplementation program throughout the winter season. As I mentioned earlier, a visual appraisal was not enough to know how good or bad the hay turned out. This is information that you can only get by forage testing. While there is a cost to testing, the knowledge it provides to ensure you are providing the proper nutrition to
your livestock is invaluable. It is a general recommendation that each harvest, from each field, be sampled and that the sample be submitted for testing. If you purchase all or a portion of your hay, you should sample several bales from each purchase to have those tested.
If you are interested in knowing more about the nutritional requirements for your sheep and cattle, I would recommend two fact sheets. Those would be the Nutrient Requirements of Beef Cattle (publication E-974) from Oklahoma State University and the Nutrient Requirements of Sheep from Oregon State University Extension.
We recently emailed out the fall edition of the OSU Extension Wayne County ANR newsletter. The newsletter is produced four times each year. It includes several articles written by Frank Becker and me, copies of the newest fact sheets produced by OSU Extension and announcements of upcoming local programs. If you would like to be
added to our email list, or you would like to receive a hard copy in the mail, contact us at 330-264-8722 or you can email me at yost.77@osu.edu. I hope that you have a safe and productive 2025 harvest season.
John Yost is an extension educator IV, Agriculture and Natural Resources, at OSU Extension-Wayne County.
This article was previously published in The Daily Record.