Last fall we analyzed almost 600 hay samples as part of the Eastern Kentucky Hay Contest. Here is a summary of what we found:
· Crude protein (3.2 to 21.7%) and total digestible nutrients (41.8 to 68.3%) varied widely
· 9% of the hay samples contained less than 50% TDN
· 22% of the hay samples contained less than 8% crude protein
· Only 85 samples or 14% contained enough energy to meet the requirements of a beef cow at peak lactation
· Only 248 samples or 42% would meet the protein requirements of a beef cow at peak lactation
· 459 samples or 78% contained enough protein to meet the needs of a dry pregnant cow
· 539 samples or 91% contained enough energy to meet the requirements of a dry pregnant cow
So, what does all of this tell us? The results of these 600 samples tells us that if you are feeding hay to lactating cows, you will likely need to provide some type of supplement to keep cows from loosing condition, especially first calf heifers that are trying to grow and feed a calf.
So, don’t these results tell us? Since there was such wide variation in both crude protein and energy for the hay samples in this dataset, no recommendations can be made on what or how much to supplement. To make this type of recommendation, you will need to sample the hay by lots (one cutting from one field) that you will be feeding (see last month’s article in the Cow Country News). Once you have the results in hand, then a supplementation program can be designed by either working your local extension agent or veterinarian or by using the UK Beef Cow Forage Supplementation Tool, found at http://forage-supplement-tool.ca.uky.edu/.
It is important to realize that both hay testing and the UK Beef Cow Forage Supplement Tool are NOT perfect. They are designed to get you in the ballpark and let you know if there is going to be a real problem with the hay that you are feeding. The true test is how your cows perform on a given hay lot. If you need help with hay sampling or interpreting your hay testing results, make sure and contact your local extension agent.
Forage testing is available from a number of commercial labs and the Kentucky Department of Agriculture. More information on this program can be found here. Make sure and use a lab that has been certified for accuracy and precision by the National Forage Testing Association. A list of certified labs can be found at NFTA Certified Labs.