Whole Grains are Good for Calves, Too

You may be old enough to remember the time when bleach-white Wonder® Bread was a dietary staple in most American homes.

But over time, nutrition research revealed the multiple merits of less-processed whole grains. Their higher fiber and protein, plus more vitamins and minerals, have been proven to improve blood sugar levels, digestive processes, heart health and more.

Now, it appears that calves, too, may benefit from whole versus processed grains in their diets. Dr. Michael Ballou, Professor and Chair in the Department of Veterinary Sciences at Texas Tech University, shared insights into the value of feeding whole grains on a recent webinar hosted by the Dairy Cattle Reproduction Council.

Ballou said fermentable carbohydrates are the name of the game when it comes to rumen development and maturation in young calves. But the traditional method in which those carbohydrates have been delivered via calf starter may require a second look.

He cited a recent University of Wisconsin study that compared a starter that delivered 43% starch and 15% NDF using ground corn and oats in a pelleted formulation. That product was compared to a texturized starter delivering 35% starch and 25% NDF via whole corn, oats, and cottonseed hulls.

“Don’t get hung up on the pelleted versus texturized formulations,” he advised, noting that the difference in starch and NDF levels are the more important comparison.

Despite the pelleted ration being the more “conventional” calf starter formulation that packed a large punch in terms of fermentable carbohydrates, the consumption patterns and resulting weight gain were quite surprising.

For example, at 7 weeks of age, calves were consuming 3.1 pounds of dry-matter of the higher-starch, pelleted ration, while the calves on the lower-starch ration consumed 4.6 pounds of dry matter per day. This resulted in a net increase in total starch consumption of 153 more grams of total starch for calves consuming the lower-starch ration (pelleted: 481 g., texturized 634 g.).

That consumption translated into significantly different growth and weight gain between the two groups post-weaning. At 16 weeks, the calves on the lower-starch, whole-grain ration weighed an average of 352 pounds – about 80 pounds per head more than those on the higher-starch ration.

“A couple of years ago, I would have said, ‘You’re leaving some growth on the table by feeding a starter like that’ – when in reality, they saw really good growth with it,” stated Ballou. “Although it was formulated at a lower starch level, it produced healthier rumens and impressive improvements in average daily gains.”

He said the high-starch starter likely limited growth due to ruminal acidosis, a theory that is supported by lower rumen pH and higher rumen lesion scores for calves consuming it.

The researcher is so confident in those results that he has shifted feeding strategies in his own calves. Ballou raises calves in both the Midwest and Southwest. A standard starter ration for his calves consists of just protein pellets, whole corn, cottonseed hulls and molasses, with a little chopped, low-nutrient forage added near weaning.

“I have a study going right now in which I’m feeding a calf starter that I would not have touched a few years ago,” he added. That ration has a starch percentage in the low 20s, with high levels of digestible NDF via wheat middlings and soy hull pellets.

Ballou has a hunch that rethinking starter grain formulation strategies may hold some clues in solving the mystery of liver abscesses that plague fed dairy and dairy-beef calves, by helping develop a healthier rumen in the first 6 months of life. He said on a percentage basis, fermentable carbohydrates may actually impair rumen development and set calves up for rumenitis due to suppressed starter intake and lower rumen pH, with subsequently lower average daily gains.

The solution: feed whole grains, and bump up fiber levels via higher NDF values. “We know fermentable carbohydrates are going to stimulate rumen development,” declared Ballou. “We just need to deliver them in a smarter way.”

Source: Dairy Herd