Eastern and central Kansas provide prime spring grazing land for much of the nation’s growing beef cattle each year. In drought years, stocker operators get creative to find alternatives to premium pasture.
During the Tamegrass Stocker Field Day in Girard, Kansas, Kansas State University professor and stocker unit manager Dale Blasi presented some of his current research in feeding stocker cattle.
“In eastern Kansas — if you define drought as years with less than two-thirds average annual precipitation — you guys have that experience about 20 percent of the time,” Blasi said. “If you go out further west, it’s more likely around 30 percent of the time and so we have to build that into our management and approaches to crops as well as livestock.”
In feeding stocker and feedlot cattle, dry matter intake is always a critical point of discussion. How much to feed or how soon after integration are critical problems to solve industry-wide.
“Dry matter intake drives the whole equation with health as well as performance,” Blasi said. “When we bring in calves, especially if we have no known history on the animals, we don’t want to compound their stress.”
Blasi said receiving rations as a whole present nutritional conundrums that challenge nutritionists and producers alike.
“One of the nutritional paradigms is that as you increase the density of energy in a receiving ration, there is a tendency for an increase in sickness, in morbidity,” Blasi said. “What we also see as you increase the energy density in receiving rations is an increase in performance.”
Removing roughage from cattle too quickly or introducing too much starch to calves not acquainted with higher levels could be reasons for increased morbidity in high energy receiving rations, Blasi said.
The limited use of high-energy diets in receiving protocols is related to the increases in the instance and severity of sub-acute and even acute ruminal acidosis that traditionally appeared under those protocols.
“A lot of consultant nutritionists wouldn’t even touch this one,” Blasi said. “It’s too risky for them to even contemplate trying to get more energy packed in and unfortunately it’s in the form of highly fermentable feedstuffs such as corn.”
Limit feeding isn’t a new approach. The concept was introduced in the 1980s and remains under research today.
Blasi explained limit feeding as a buffet versus boot camp approach to feeding stocker cattle.
“Just keeping those bunks full for the calves is similar to going to Las Vegas, where you go to an all-you-can-eat night buffet and just eat until you’re crazy,” Blasi said. “Contrast that with the highly structured diet you would get in a military boot camp for basic training.”
A ration formulation used in Blasi’s research would contain 40 percent wet co-product feeds, 38 percent rolled corn, 6.5 percent alfalfa, 6.5 percent prairie hay and 8.2 percent supplement. It’s a high-energy approach to feeding given once a day at 1 percent of the cattle’s body weight upon arrival and increased at 0.25 percent per day until it reaches 2.2 percent of body weight.
“Limit feeding increases dietary energy and reduces feed intake, slowing down the passage of rate of the digestive process going through the rumen,” Blasi said. “As it goes through the site of absorption, there’s greater opportunity and what we tend to see is an improvement in digestibility.”
The first trial completed using limit feeding protocols followed 354 crossbred heifers at Kansas State’s Stocker Unit. The heifers originated from Tennessee and were introduced to a limit feeding protocol upon arrival.
Over the course of the study, researchers noted a 27 percent increase in gain efficiency over the control animals fed a standard stocker diet, with no notable adverse health effects.
The second study tested the ruminal digestibility of the limit feeding ration using cannulated steers. Researchers saw a significant drop in rumen pH around six to eight hours after feeding — around a 5.4 pH for limit fed steers versus a 6 pH for the control group. The number was very low but just above concerning levels.
In the same study, researchers saw a linear increase in feed efficiency in line with the first study.
“We’re seeing a 27 to 30 percent improvement in feed efficiency across our last few trials,” Blasi said. “There are a lot of questions yet to be answered in our future trials about this feeding system, as well.”
High co-product inclusion is one of the foundational aspects of limit feeding protocols; however, Blasi said they did some additional research trying the ration using different products than the sweet bran the unit typically uses.
“The bottom line is we saw no difference in performance with average daily gain between rolled corn, whole corn or sweet bran versus wet distillers in these rations,” Blasi said. “They all performed equally in growing calves.”
Sustainability & Efficiency
Limit feeding might seem a bit intimidating to producers without a vast nutrition background and a passion for feed mixing, but the process answers a lot of consumer concerns about beef sustainability. Limit feeding reduces labor associated with filling feed bunks and limits feed waste, Blasi said.
“Limit feeding vastly simplifies feed bunk management,” Blasi said. “We feed our calves once a day and by five hours after, the bunks are stripped clean, so if we get a rain event or a snow event, there’s no scoop shovels involved.”
In light of this new era of antimicrobial concerns, Blasi said limit feeding also simplifies health protocols and locating animals needing treatment.
“If you eat and you consume everything within five hours and all you can do the rest of the day is lay around, when it comes time to eat if you’re not up at that bunk looking pretty enthusiastic about eating, that really is a sign used for health detection,” Blasi said.
Because limit feeding is a low-roughage diet, animal waste and manure handling decreases, Blasi said.
“Limit feeding uses less roughage and as a consequence less manure handling, which can be a really big benefit,” Blasi said. “Manure handling is a millstone around producers’ necks and it certainly is around ours at the stocker unit.”
In the K-State Stocker Unit trials, Blasi calculated a 58 percent reduction in manure using a limit feeding approach. The reduction also reduces manure handling costs, thanks to a fairly common sense approach.
“For the amount of forage we put in the 60 NEg diet, we didn’t really see any decrease in the amount of fiber that was digested by the ruminal microbes in that higher energy diet,” Blasi said. “Forage is marginally digestible and is a diluent inside the diet — if it’s only marginally digested the animal is going to make more manure.”
Blasi said ancillary benefits abound for stocker producers willing to take an educated approach to limit feeding stocker cattle.
“All of these things begin to accrue when we’re talking about limit feeding,” Blasi said. “Less time feeding, less trips to the feeders and less time mixing are all things we hope to validate during our next study focused on the costs and labor associated with these protocols.”