Cattle feeders aren’t just feeding cattle — they’re also feeding the microbes that live in the rumen.
And those little critters are picky.
“Regardless of the production system, the challenge that we face is variation in dry matter intake and total nutrient intake,” said Greg Penner, assistant professor of animal and poultry science at the University of Saskatchewan.
“If we’re looking to promote rumen health, we need to ensure we’re providing those cattle — and in the end, those microbes — a consistent supply of dry matter, as well as adequate nutrients so that they have the tools required to do their job.
“Focusing on management strategies that minimize variation in intake will achieve the greatest rewards for your operation.”
Through digestion, gut microbes turn feed into energy, protein, and nutrients. When the right kinds of microbes are working well in the rumen, cattle use feed more efficiently and have a reduced risk for digestive diseases.
But variations in diet can affect how microbes digest feed.
“The microbes have to respond to those changes in nutrients that are provided in the rumen and adapt to those responses,” said Penner. “Unfortunately, not all of those responses are beneficial.”
Feed with variable energy, for instance, will create a different “growth response” in the microbes.
“If the growth response is not well controlled, the result can be harmful products such as antigens, and these antigens can actually induce an immune response,” he said.
Because of that, cattle feeders need to balance having an “active microbial population” with regulating the population.
“We want that microbial community to be focused on fibre digestion to ensure there’s adequate nutrients for the cattle, but also to make sure they’re efficiently digesting those feed components.”
And providing a consistent feed supply is the best way to do that.
“Whether it’s a forage-based diet or a concentrate-based diet, we need to ensure we have a consistent supply of dry matter and a consistent and adequate supply of nutrients to meet the microbial nutrient demand and to meet the cattle nutrient demand,” said Penner.
Dry matter matters
Ensuring cattle have adequate feed is the first step — but improving access to dry matter can be equally important, he said.
“You’ve got to ensure you’re restricting access to extensive feeding systems to ensure that they don’t simply overindulge on those tasty corncobs or barley cereal grains and leave the fibre for later,” said Penner.
“I know of producers who are providing additional forage to ensure adequate dry matter intake.”
For feedlot or backgrounded cattle, bunk management “plays an incredibly important role.”
“You’ve got to be reading those bunks and feeding based on the behaviour of those cattle and the amount of feed available in the bunk.”
Monitoring grain processing is another practice that can be done “fairly easily.”
“It not only prevents overconsumption but also ensures that you have adequate fermentation of that potentially expensive cereal grain,” said Penner.
Using ionophores is “one easily adoptable feeding strategy” that can also stabilize rumen fermentation.
“There’s an extensive use of ionophores in the beef industry, and they’re very effective tools to stabilize dry matter intake by the cattle,” he said. “They help to manipulate rumen fermentation to make that fermentation process more efficient and certainly resulting in greater efficiency in feed utilization.”
Cattle feeders are “probably already doing a lot of these things” on their operations, he said, and that’s what’s going to improve production performance.
“If we’re looking for the greatest reward in terms of management strategies, it comes back down to basic management and simply minimizing variation for dry matter intake and nutrient intake in your cattle.”