Published figures show that 29 percent of the July feedlot placements weighed more than 800 pounds when they entered the yard. Well over half of these cattle were over 700 pounds. These relatively heavy start weights would intuitively lead to shorter days on feed—something that is supported by the historic values from Kansas State University’s Focus on Feedlots report. If we look at June fat cattle data from the last five years, we see a gradual increase in days on feed up to 2008, when this number took a noticeable step back.
The obvious explanation is high grain prices—and the significant production corollary is a need to grow calves and yearlings to heavier weights on grass or other forage-based feeding systems.
With this renewed focus on growing and backgrounding cattle, Dr. Glenn Selk, Oklahoma State University (OSU), recently took a hard look at the old rule-of-thumb that said a pound of added gain on young cattle was worth about 55-60 cents. What he found, based on current prices and the existing price slide, was that a more accurate figure would be closer to 80 cents per pound. That is an important number because it allows us to put a dollar value on management practices that increase gains. Specifically, it can be combined with an expected conversion rate to project expected returns on supplementation.
Producers have two basic options when it comes to supplementing cattle on grass (or harvested forage): low-protein/higher energy feeds, or protein supplements.
Products with less than 20 percent crude protein are most effective in situations where it would be desirable to partially substitute for dietary forage. Hay may be in short supply, or the primary goal may be to maximize pounds produced per acre. Energy is often the nutrient of primary concern, delivered with relatively high intakes of supplemental feed. The energy source—starch, fiber or sugar—will have a huge impact on both effectiveness and efficiency of this program. As long as the cattle’s diet is primarily roughage, limited grain feeding will disrupt fiber-digesting activity in the rumen, partially or totally offsetting he positive contribution of the starch.
These "negative associative effects" have been well documented, and should be avoided. Selk cites data where a 14 percent protein, grain-based cube was fed to stocker cattle at 4 pounds per head daily. Average daily gain did increase about 3/4 pound, but the conversion was 5.4 pounds of supplement for every one pound of additional gain. As I mentioned above, we can determine a breakeven price for purchasing supplement; in this case:
Value of added gain (80 cents/pound) divided by a conversion rate of (5.4) x 2000 = $296 breakeven. In other words, if the cube costs $296/ton, the added gains will be worth only what it cost in feed to get them. If the price goes above $296, supplementing this way would yield a net loss. On the other hand, nutrient-dense supplements with fiber or sugar energy should complement utilization of the forage.
Depending on management goals, these feeds can boost gains on a per animal or per pasture basis. In work recently completed at the USDA research station in El Reno, OK, stocking rates on spring fescue were increased from 1.7 to 3.0 when a 20 percent protein liquid supplement was provided in lick tanks. Individual gains did show a decline in the supplemented group, but gains per acre over a 52-day period went from 175 to 250 pounds. Protein supplements (>25 percent crude protein) are fed at low levels to stimulate intake and digestion of the available forage. Here, too, supplemental energy source matters. If degradable protein is supplied with fiber or sugar energy sources, rumen microbial activity increases and cattle are able to take in more grass or hay, and get more good out of it. When gains are limited by forage quality, rather than quantity, this program can boost performance with minimal purchase of non-forage feeds.
OSU’s "Oklahoma Gold" program is based on the validated expectation that feeding 1 pound of a 38 percent protein supplement will increase gains 0.43 pounds. That is a conversion of 2.3. At current prices, the breakeven for this supplement would be:
Value of added gain (80 cents/pound) divided by a conversion rate of (2.3) x 2000 = $695 breakeven. So, even with significantly higher feed prices, most protein supplements are still a cost-effective buy.
If we were to apply this to liquid supplements, the conversion rate (pounds of intake needed to yield 1 pound of additional gain) should be adjusted for dry matter. For liquid feeds with a percentage dry matter content in the mid-60s, the conversion would be about 3.25. This figure matches the average results reported in research papers and field studies. In one test conducted in Virginia, however, a group of steers consuming 1 pound of liquid feed per day gained an additional 57 pounds in 63 days, for a 1.1 conversion.
Using the more conservative 3.25 figure, this breakeven would be:
Value of added gain (80 cents/pound) divided by a conversion rate of (3.25) x 2000 = $492 breakeven. Again, even at current prices, supplementation should be a sound investment.
The most-informed supplementation decisions will be based on total, rather than retail, costs. In other words, the appropriate breakeven price should be compared to the complete cost to deliver supplemental feed to the animals. Transportation costs for daily feed delivery are now too significant to overlook. Suppose, for example, a ton of high-protein cubes is purchased for a group of yearlings located five miles from home (10-mile round trip). At a one-pound feeding rate, they would last 20 days. Assuming a 50-cent mileage rate and daily feeding, the added cost for that one ton of feed is $100, which would reduce the $695 breakeven shown above to $595. Other relevant expenses include time and labor, equipment, and waste allowance.
The bottom line is that despite the dramatic increases we’ve seen in the price of feed, appropriate supplementation is still a cost-effective investment for growing cattle. — Cathy Bandyk, cattle nutritionist, Quality Liquid Feeds