Protein supplementation is relevant in a drought year or during dormant season grazing, particularly on native forage
MOOSE JAW, Sask. — Cattle producers struggling to deliver proper protein in dry conditions and with poor feed sources could consider supplementing with canola meal, says a University of Saskatchewan professor.
Dr. Greg Penner said a study funded by both industry and the federal government compared feeding heifers canola meal and dry distillers grain as protein supplements.
The canola meal cost more to buy, but was more cost efficient in the end, he told the Saskatchewan Stock Growers Association convention.
It ended up saving five cents per head per day in feed costs.
Dry conditions earlier this season moved grass into a reproductive state early and toward senescence. When that happens, fibre content goes up and crude protein goes down.
Penner said protein supplementation is relevant in a drought year or during dormant season grazing, particularly when cattle are on native forage.
Research has shown that dormant native forage has less than eight percent protein, while crop residues contain four to seven percent crude protein.
“In cattle, we have a seven, nine, 11 crude protein rule,” Penner said.
Cattle need at least seven percent protein during maintenance, nine during early gestation and 11 percent in late gestation.
Crop residues and stockpiled forages are not going to meet those requirements.
Using a trust-me-I’m-a-professor caveat, Penner said metabolizable protein is a better marker for beef cattle.
“I can actually formulate diets for milking beef cows at seven percent crude protein but still have adequate metabolizable protein,” he said. “If we want to have more economic diets we need to shift our mindset away from crude protein and use values that are actually meaningful from an animal requirement perspective.”
The study involved 15 heifers in pens of three. Five had rumen cannulas so researchers could observe what was happening and assess fermentation.
A negative control pen received grass hay. Other treatments received either canola meal or DDGS pellets every day, or every second day. The pellets were large, at about 11 millimetres in diameter and suitable for range conditions.
Penner said many ethanol plants are now stripping the oil from their DDGS, which consequently lowers the protein content. As a result, the study required more DDGS to be fed.
The study found that the heifers fed the protein supplement ate more forage.
“In the case where we’re feeding a very poor quality forage I think that’s a beneficial response,” Penner said. “We want to stimulate the rumen.”
The animals that didn’t receive any supplement gained only .44 pounds per day, while the others gained 1.3 pounds per day. The growth rate was low, he said, and performance would be affected.
The added protein increased the amount of acid in the rumen, which is a benefit because it allows the animals to absorb the acid for energy. As well, rumen ammonia went up and that provides a source of nitrogen as the cattle recycle it.
The supplements did not affect forage intake, but more DDGS pellets were consumed because more were delivered to provide the same amount of protein as the canola pellets.
“Canola meal was more rumen degradable,” Penner said, which makes more ammonia available.
The study also showed that it didn’t matter if the animals were supplemented daily or every second day in terms of rumen fermentation or available nitrogen, but behaviour was affected.
“When we fed that pellet every second day the cattle anticipated being fed that pellet and they ate faster,” Penner explained. “While they were eating faster they were also more aggressive.”
He said producers should consider grouping strategies if feeding mature cows and young heifers.
From a financial standpoint, the DDGS cost $360 per tonne at the time of the study and the canola cost $380 per tonne. Penner divided that cost by the amount of protein in each to determine that canola meal was more cost effective.
The pellets were fed on artificial turf grass so that researchers could see how much was eaten or lost. About 10 percent was left behind, which is an economic consideration.
He said ranchers should think about potential opportunities considering what is happening with canola exports to China. Canola meal also presents fewer mycotoxin risks compared to DDGS.
He said studies have shown that whole canola can also be successfully fed to cattle and with feed in short supply producers will be looking for all types of options.
The corn crop coming out of Nebraska will be down this year due to flooding and feed supplies in some parts of Saskatchewan will be short.
“I would be looking for non-conventional (sources) and if we can get some off-grade oilseeds, cereals or pulses that’s where I’d be looking,” he said.