Cubes or tubs, blocks or liquid, daily or weekly? Protein and energy supplements come in different forms to accommodate different production systems, and the choices involve tradeoffs in terms of convenience, cost and cattle intake. During the recent Cattle Industry Convention in San Diego, Texas A&M University animal scientist Jason Sawyer, PhD, outlined some considerations for delivery of supplements in cow-calf operations.
Sawyer began by offering a simple way to calculate the protein requirements for cows. For a dry cow, divide the cow’s weight by 1,000 and that is roughly how many pounds of crude protein (CP) she should consume. So for a 1,200-pound cow, that is 1.2 pounds CP per day. Double that number for lactating cows, Sawyer says. While simple, this method requires a reasonably accurate estimate of the average cow weight in a herd.
As for frequency of supplement delivery, Sawyer says that if the supplement contains 30% CP or more, delivery once or twice per week results in performance similar to every-day delivery, but with less labor. If, however, that supplement also contains an energy source, delivery should be every day to avoid problems associated with excess energy consumption.
If the supplement contains less than 30% CP Sawyer recommends delivering it daily or every other day.
Naturally the form of the supplement influences delivery times and labor expenses, and also can also affect intake and uniformity of consumption. Hand-fed supplements such as range cubes, pellets, cake or blocks, which are delivered in a form and amount intended for short-term consumption, offer flexibility in ingredients, competitive pricing and can be used to move cattle.
Self-fed supplements such as tubs or liquid feeders are intended for longer-term consumption and may contain ingredients intended to limit daily intake. These reduce labor requirements but also create some tradeoffs.
With hand-fed supplements, Sawyer says research has shown intake, with a target of 2 pounds per day, will range from 0 to 3.5 pounds per day, and about 5% of cows will be “non-eaters” that do not receive any or enough supplement. With self-fed supplements, intake varies more, with a range of 0 to 5.5 pounds per day, and up to 19 percent of cows will be non-eaters. The numbers will vary between herds, but Sawyer says the general trend is for more consistent consumption with hand-fed supplements. If using self-fed supplements, he recommends monitoring body condition scores (BCS) in the cow herd to spot any cows that might be losing condition as a result of insufficient supplement intake.