By MARCEL WALLAU, DOUG MAYO, and CHRIS PREVATT University of Florida
How Good is Your Hay? The first thing we do when shopping for dry feed is to ask “how much crude protein (CP) and total digestible nutrients (TDN) it has,” right? How come we never ask that about hay? It’s about time we are all putting hay up for next winter, and our main goal is to get that barn filled (I hope you all have a barn, as it really pays off fast, just counting
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on the losses on hay stored outside). But what most of us don’t generally consider is how good that hay is. I understand we have too many cows to feed, and we need quantity first, and we can adjust the nutrition later with supplement. But does it really pay off? What is the cost of that poor quality hay? And what does it mean when commodity prices are so high?
The Carolina Cattle Connection q AUGUST 2021
Figure 1. A tale of three hayfields: how difference in hay quality and cost can influence cost of winter feeding? (picture: Doug Mayo).
Hay feeding plays a major role in cow/calf operations in the southeast, if only to feed between the last grazing of the summer pastures and the first of the cool season grasses, or as the base of a whole winter feeding program. The fact is, hay quality often gets neglected. Knowing the digestibility or TDN and crude protein of the hay is key to determine how much supplement we need to achieve the desired productivity goals. Overfeeding is expensive because we are wasting money; underfeeding is expensive because our animals are not performing adequately. But there is much more to that. Low quality hay can reduce total intake because of gut fill, increase waste (i.e., animals are trying to sort out in hope for better forage), both reducing performance and increasing cost. We take for granted that cows (especially dry cows) can eat just about anything. The famous “cow hay” can be a trap, reducing performance (loss of body condition score, lower pregnancy rates, etc.) and result in less profit. Hay can be an expensive product based on nutrient content, and investing in quality often pays off. Let’s take a look at some numbers. Below is a basic economic example. It isn’t all inclusive but gets us close to analyzing the economics of winter feeding systems. Considering three sources of hay (Figure 1), a well managed Tifton 85 bermudagrass, a fertilized Tifton 9 bahiagrass, and unfertilized costal/bahiagrass mix, at $60, $50, and $45 per 800 lb bale (Table 1). The cost per lb of protein on the hay goes from $0.54 on the high quality hay to $0.94 on the low quality hay! Considering soybean meal at an approximate cost of $346/ton as fed with 50% CP and 84% TDN, then it costs $0.39/lb of CP and $0.23/lb of TDN on a dry matter basis. Now let’s plan a diet of a dry, 1,100 lbs beef cow in midto late-gestation, requiring a maintenance diet containing 7% CP and 47% TDN. The nutrient CP and TDN requirements of the dry cow are met with the T85 hay, not needing supplementation. However,
our cost goes up 20¢ per day per cow when we feed low quality hay and need to provide 6.8 lb/day of soybean meal to those cows (~0.6 percent of body weight). And this is not considering the extra labor. Turning the table, what if we are producing and selling hay rather than feeding? Managing your hayfield properly can result in more biomass production, and if you are able to market hay based on quality, there are significant advantages here! Table 2 brings a simple example with the same three hay types mentioned above from a seller’s perspective. With good care (i.e., proper cutting management, fertilization, and weed control), pastures can produce more biomass of greater nutritive value, which can bring higher profit. How to make your hay better? First, let’s see what factors affect hay quality the most: • Forage species and cultivar - some forages just have better nutritive value than others. Legumes, for example, are higher in protein than perennial grasses, and bermudagrass is generally higher in TDN and CP than bahiagrass. Within species, different cultivars or hybrids may have large differences. Tifton 85 is around ten percent more digestible than coastal bermudagrass and has greater biomass production. When planting your hayfields, take that into consideration. • Cutting interval, regrowth period, or maturity - this is the most important factor when cutting hay. The more mature the pasture is, the lower the nutritive value. Some species have a steeper decrease in nutritive value compared to others. There is always the compromise between quantity and quality. Longer regrowth periods (but not excessively long) will result in greater biomass production, but that comes in detriment of nutritive value. Thus, hay producers do not want to cut it too early because the yields are too low. • Drying process - the faster the forage is dried, the smaller the nutrient losses. Those come in two ways:
