MANHATTAN – When training for a sports competition, athletes often adjust their nutritional needs to match the exercise program. Similarly, a pregnant bovine cow’s nutritional needs increase as she nears the birthing event, experts at Kansas State University’s Beef Cattle Institute said on a recent Cattle Chat podcast.
“As the cows enter the third trimester, the need for energy and protein increases as most of the fetal growth takes place,” said Phillip Lancaster, cattle nutritionist.
He said cows raised on dormant domestic pastures must be given additional feed that contains both protein and energy supplements.
“The timing of when the cows are left with hay depends on their gestation stage and whether or not the standing feed meets these requirements,” said Lancaster.
The type of grass they graze will also guide the decision on which to supplement.
“With a cool season grass like fescue, if it’s green under the brown grass above, it still has good protein and digestibility and can meet the nutritional needs of the cows,” said Lancaster.
The decision as to when to spread hay also has a cost component, says agricultural economist Dustin Pendell.
“Our research shows that the most profitable calf farms tend to have the lowest out-of-pasture feed costs,” Pendell said. “Some producers make a compromise, whether they let the cows graze a little longer in the pasture or feed them hay.”
With cattle nearing calving, veterinarian Bob Larson said he prefers cows to calve in pasture rather than in a barn or drying area.
In order not to damage the new growth of these pastures during the calving season, it is important, according to Lancaster, to relocate the source of feed so that the cows spread their manure and minimize the concentrated damage to the grass caused by cows standing around.
Larson added, “It’s important to roll out the hay in a different place each time.”
According to Lancaster, producers must evict the cows from the pastures a little earlier so that the grass can rest before the summer pasture.
“New green pastures, where the cows graze all the leaves of the grass early, will actually stunt the growth of that grass for the growing season, so it is important to switch pastures,” said Lancaster.
