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Minimizing Hay Storage and Feeding Losses

Hay is the most widely grown, mechanically-harvested agronomic crop in the United States. According to USDA, in 2019, the United States produced more than 57.7 million acres of forage crops harvested for hay. Annual production from this acreage is over 140 million tons of hay valued at more than 18 billion dollars. Stored feed, including hay, is normally more expensive than pasture forage, so it is economically advantageous to minimize storage and feeding losses to the greatest extent possible. The objective of any hay feeding program is to provide adequate quantities of high quality hay to meet livestock needs not being met by pasture. It is estimated that more than half of the annual cost of feeding a beef cow is winter feeding.  For many producers, it’s the single largest expense in running a cow. This is due to the cost of machinery, fertilizer, fuel, and labor to make, store, and feed the hay. Therefore, it is critical to maximize feeding efficiency and minimize the waste in storing and feeding hay. Let’s consider some of the options available to help achieve these goals.

Hay can be made from many different forage crops. When protected from the weather and other elements, it can be stored for long periods of time with very little nutrient loss. Hay can often meet the nutrient demands of many classes of livestock.

Hay has many merits. Unfortunately, improper storage and feeding techniques can result in losses upwards toward 50% of the hay that was harvested in the field. This is particularly true with round bales stored outside in high rainfall areas. Hay storage losses vary greatly depending upon several factors, but storage technique is one of the most important. Research conducted at the University of Tennessee (UT) a few years ago studied hay losses in storage. The research compared different methods of storing large round bales of grass hay.

The hay was cut and baled in June in Moore County, TN. The bales were weighed at the time of harvest and storage, then weighed again the following January at the time of winter feeding. Different storage methods were used and testing indicated the level of loss using each. Here’s how various storage methods of large round bales fared in the UT research:

  • Stored on the ground with no cover, 37% loss.
  • Stored on tires with no cover, 29% loss.
  • Stored on the ground and covered, 29% loss.
  • Stored on tires and covered, 8% loss.
  • Net wrapped and on the ground, 19% loss.
  • Stored in the barn, 6% loss.

The research showed that significant quantities of loss were incurred depending on the type of storage method selected. Many producers do not realize how expensive this can become or how large their losses really are. Dry matter losses during storage result from respiration and low numbers of micro-organisms, but this is constant across hay types and essentially unavoidable. At safe moisture levels, hay stored inside typically loses around 5% of dry matter, but losses several times higher have been reported for extremely moist hay. Heating of hay is related to moisture content. Heating occurs at moisture levels above 20%. This is caused by increased microbial activity. Mold begins to form and both forage quantity and quality decrease. Producers also need to consider the danger of stored hay going through a “heat” and combusting spontaneously.

Some of the dry matter loss which occurs during outside storage is caused by leaching. This is where nutrients are dissolved and removed from the bale by rain water passing over the surface of and through the bale. The more digestible nutrients are, the more soluble they are, so the more likely they are to be removed by leaching.

As more producers switched from square bales to round bales, storage losses increased and quality decreased. Round bales are not necessarily poorer quality. However, rolls that are stored outside, with no protection, in adverse weather from baling to feeding show greater losses.

Impacts of the weather affect hay in the outside circumference of a round bale rather than in the ends. Consequently, the diameter of the bale affects the proportion of the bale contained in the surface layer. Dry matter loss from hay that is not stored properly also translates to loss in forage quality.

Here is an example to consider. A 5’ x 4’ bale of bermudagrass hay weighing 1000 pounds that is stored outside, on the ground, and uncovered. The 4-inch outside layer has been degraded and represents a 30 percent dry matter loss. This means a 300 pound loss per each 1000 pound bale. The hay analyzed at 10 percent protein and 58 percent total digestible nutrients (TDN). Forage quality loss amounts to 30 pounds of protein and 174 pounds of TDN. To replace the TDN lost with pelleted corn gluten feed at a cost of $9.00 per CWT, the replacement cost is $15.66 per bale of TDN. Replacing protein losses using soybean meal at $15.00 CWT will cost $4.50 per bale. In addition to having to purchase feed to supplement the dry matter loss, additional hay must be purchased to replace losses from storage and feeding.

On many farms, hay feeding losses are as high as storage losses. This is true because as the amount of weathered hay increases, animal refusal also increases. Some hay losses during feeding can be expected with any feeding system, but the amount of loss varies with the system used.

The chart below shows the percent waste as determined by the feeding system:

Square bale in a rack7
Large round bale in a ring9
Large round bale w/o a ring45

Bell, S. and F. A. Martz. 1973. Res. Rept. Univ. of Missouri Agric. Exp. Sta.

The major objective for any feeding system should be to keep losses to a minimum level, thus permitting animals to consume the majority of hay offered at feeding. Feeding losses include trampling, leaf shatter, fecal and urine contamination, and refusal. The levels and costs of these losses will be determined by feeding method, intervals between feedings, amounts fed at a time, weather conditions, the number of animals being fed, and forage quality.

Below are some helpful hints to avoid feeding losses:

  1. Minimize waste
  2. Feed hay in small amounts – This limits trampling and spoilage.
  3. Use a feeder – Feeding hay in a rack or a “hay ring” also limits the opportunity that animals have to trample or soil hay, and will reduce waste substantially.
  1. Feed hay in well-drained areas – Standing in mud and water increases the stress levels.
  2. Move hay-feeding areas around the farm – This minimizes the damage to any one area of the pasture and spreads nutrients over a larger area since cattle congregate at feeders. If you intend to feed hay in one location, provide a footing such as crushed gravel or concrete to help minimize mud.
  3. Feed hay stored outside before feeding hay stored inside.

You would never consider throwing away one-third of your hay.  That is what happens when livestock are allowed unlimited access to hay. The largest hay losses occur when large hay bales are fed without animal restrictions. Livestock trample and waste 25 to 45 percent of the hay when it is fed in this manner. The lowest hay losses result from hand feeding livestock the amount they will consume at one time. However, the labor expense for the big hay bales is lower, and hand feeding requires more labor. The most economical feeding system is somewhere in between.

Hay is one of the most widely used components, used to supplement forage, of any livestock feeding program. With the cost of inputs required to make hay, it is important for producers to minimize storage and feeding losses to the greatest extent possible. Hay can provide needed nutrients/feed for animals. However, the livestock producer must pay close attention to the quality of the hay and also mitigate as much as possible the factors influencing losses during haymaking, storage and feeding.