Alternative proteins reduce calf growth
New research from the Akey Nutrition and Research Center in Lewisburg, Ohio, examines the effect of using wheat and rice protein sources in the milk replacer of calves less than two months of age.
The study’s findings support the recommendation to avoid non-milk sources of protein in the milk replacer of young calves. Here is a look at the results, which were published in the October 2008 issue of The Professional Animal Scientist.
In trial 1, the researchers evaluated a 20-percent protein, 20-percent fat milk replacer containing 0 or 4 percent hydrolyzed wheat gluten. They fed each milk replacer for 42 days. Wheat-protein inclusion of just 4 percent reduced weight gains by 15 percent, says Mark Hill, the study’s lead author. Calves fed the wheat protein also had lower starter intake, feed efficiency and hip-width change than calves fed no wheat gluten.
In trial 2, the Akey researchers compared a 26-percent protein, 17-percent fat milk replacer containing 0, 6 or 12 percent hydrolyzed wheat gluten. They again fed each milk replacer for 42 days. Weight gains of the wheat-protein-fed calves were reduced by 12 to 21 percent, Hill says. Calf growth, starter intake and hip-width change declined as the amount of wheat gluten increased.
In trial 3, the researchers examined a 26-percent protein, 17-percent fat milk replacer containing 0, 8 or 16 percent rice protein concentrate. They fed each milk replacer for 28 days. The rice-protein-fed calves gained 12 to 54 percent less weight than calves fed no rice protein, Hill says. Daily gain and feed efficiency declined as the amount of rice protein increased in the milk replacer.
Some plant proteins are lower in cost than milk proteins, which can make them appealing substitutes in milk replacer. However, as this study demonstrates, they can have detrimental effects on performance because young calves lack the ability to properly digest non-milk proteins. “It is well documented that the young calf lacks the digestive enzymes to digest plant proteins,” Hill explains. “Additionally, allergens are present in many plant proteins that damage the intestinal lining and reduce absorption of nutrients.”
This is the first peer-reviewed, published research to evaluate rice protein in milk replacer. It also is the first published study to test wheat protein and rice protein in calves less than one month of age.
