Mark Hanigan, professor of dairy science at Virginia Tech, was recently selected for a research grant to study the amino acid load dairy cattle get from different feed and feed ingredients by the Institute for Feed Education and Research, a non-profit associated with the American Feed Industry Association. The grant runs for three years and offers a total of $225,000 during that time.
His project was selected based on the possible improvements it could offer to the industry regarding animal nutrition, health and future sustainability, said AFIA. This is the first competitively awarded research grant the group has awarded.
“I need to know what the supply [of amino acids] is, and right now the supply is fairly ill-defined,” Hanigan told FeedNavigator.
Protein levels
In theory, a lower protein diet could be used with cattle and dairy cows, if supplemented with proper levels of amino acids, he added.
“If you look at the poultry and swine industries, they know their amino supply and requirements a lot better and they don’t have to worry about the rumen, so they can add raw amino acids, and get less nitrogen waste,” he said. “We aren’t there with cattle – we don’t know their requirements well, and we don’t know their supply well, so we have to over-feed protein so we make sure we’re meeting their requirements.”
Research details
The project evaluates seven different feeds, or feed ingredients including corn silage, soybean hulls, dried brewers grains, dried distillers grains, grass hay, alfalfa and corn, said Hanigan. The ingredients were picked because they are common parts of a cow’s diet.
The experiment will look at what levels of amino acids show up in a cow’s blood stream and track where the amounts lost go – either in not being digested or not moving past the rumen, he said. Examining ruminal in situ analyses allows for a direct estimate of ruminal losses and looking at the total track digestibility should give the research team additional understanding of where the amino acids are going and why.
The work will evaluate the levels of 10 different amino acids, Hanigan said.
Ongoing work and what’s next
In addition to the upcoming research project, Hanigan’s team is finishing an earlier experiment examining amino acid absorption from other feed ingredients like blood meal, feather meal and soy meal, he said.
The group also has another experiment researching the results of diets with differing protein levels and supplementing four amino acids – methionine, leucine, isoleucine and threonine, he said.
“We’ve worked a lot on post-absorption – once they [amino acids] get into the blood how are they made use of, but if you can describe all that, you still need to know what the supply to the animal is,” he said.