If you have hay left when warm spring weather arrives and hopefully some rain occurs, consider yourself fortunate. Although hay is supposed to be more plentiful this year, continued drought is forecast for much of the United States and hay will probably remain at premium prices. Last year’s hay has value depending upon its quality.
Value is determined by the absence or presence of mold, palatability and nutrient content. The primary reason for nutrient degradation in hay is moisture. Nutrient content of hay stored in dry barns remains stable indefinitely. If the hay was stored outside, expect some nutrient loss.
Determine Nutrient Content
Nutrient content of last year’s hay should be determined by taking forage samples for analysis. The ideal method of sampling hay bales is with a bale probe. Although a number of different probes are available, most cut a one-inch-diameter core from the bale. Your county agricultural extension agent may have a bale probe available for loan. If not, he or she can tell you where a probe can be purchased.
On round bales, take cores midway up the side and toward the center. Obtain sample cores from the end toward the center of square bales. Remove the outer one-half inch of the bale surface before sampling to avoid contamination by dust and debris from the field. Drill or core into the bale 12 to 18 inches deep, then carefully pour the sample into a container such as a mailing envelope, sealable plastic bag (if it is dry) or small paper sack. Do not contaminate forage samples by putting them into feed or fertilizer sacks.
Sample four to five bales from the same field and cutting. Mix the cores thoroughly into one composite sample. Obtain a composite sample from every 25 to 30 bales per field and cutting. Submit composite samples to a state or accredited commercial laboratory that is equipped to test hay. The laboratory submittal form should be completed and submitted with the samples.
Although forage laboratories can analyze for a variety of substances, it is recommended that crude protein, TDN (total digestible nutrients), and mineral analyses be requested on the sample submittal form. You can then obtain crude protein and TDN requirements of your cattle from various animal nutrition references and subtract the amounts in last year’s hay to determine the amount of nutrients needed from feed supplements.
Consult with your county agricultural extension agent on the type and amount of mineral mixes recommended for your area. Mineral requirements of cattle vary according to soil types and geographical regions. Choose a mix that provides the required minerals lacking in your hay.
Palatability is Important
In deciding what to do with last year’s hay, determine its palatability in addition to having it tested for nutrient content. “Palatable” is defined as pleasant or acceptable to the taste, fit to be eaten or drunk, and acceptable to the mind. These definitions are true regardless of the type of animal that will be expected to eat a certain food or feed. As palatability of hay decreases, nutrient content and consumption per animal will decrease as well.
Look at the stem to leaf ratio of last year’s hay. If it is composed of very few leaves and the stems are coarse and woody, palatability is going to be very low. A larger amount of supplement will be needed with this hay than is required with higher quality forage that contains a lot of leaf material and small pliable stems. One way to use hay with low palatability is to feed it to mature, dry cows because their nutrient requirements are less than when they are lactating.
It is important to monitor the daily consumption of hay, regardless of its quality. If hay consumption is less than expected, supplement amounts need to be increased to overcome the nutrient deficits. If the cattle are eating more than expected, the amount of supplement can be reduced.
Dealing with Mold
Examine last year’s hay closely. Does it smell musty and contain mold? Feeding moldy hay can result in reduced intake, less nutrient value and potential ingestion of mycotoxins. As expressed earlier, reduced intake and nutrient value are overcome by altering the feed supplement program.
Mycotoxins are a concern because they can suppress the immune system, which predisposes livestock to many diseases. A suppressed immune system may cause a lack of response to medications and vaccines. In addition to immune system suppression, mycotoxins can damage animal organs.
In cattle, mycotoxins will usually contribute to chronic problems such as a higher disease incidence, poor reproductive performance or suboptimal milk production. Ruminants are somewhat protected from acute toxicity because the rumen destroys a large portion of most mycotoxins.
Research has shown that approved binders, when mixed at low rates with feed or hay, reduce mycotoxin effects on animals. In cattle, robust rumen fermentation helps maximize mycotoxin detoxification; so sufficient fiber, buffers and microbial products to stimulate rumen function can be helpful. If hay is dusty from mold spores, feed it only in areas with plenty of ventilation.
“The effect of moldy hay can be reduced by feeding a higher quality hay and grain or commercial supplement,” said James Neel, Professor of Animal Science at The University of Tennessee. “Severely molded hay should be diluted to no more than 30 percent of the ration in order to reduce risk of mycotoxicosis and reduced animal performance. Hay with limited heat damage and mold should be diluted from 40 to 60 percent of the total ration. Do not force cattle to consume moldy hay without other forage available.”
Never feed moldy hay to pregnant cattle due to the risk of causing abortions. Before initiating a feeding program with poor quality hay, always evaluate the cost of additional supplements versus buying better quality forage and disposing of the old hay.