One of the best ways for producers of non-ruminant animals to reduce their carbon and nitrogen footprints is through use of amino acids, Dr. Jonathan Goodson told attendees at day one of the Animal Ag Sustainability Summit, held January 28 in conjunction with the 2013 International Production & Processing Expo in Atlanta, Ga.
Close to 50 percent of all soybean meal produced is used for chicken feed, while another 25 percent is used to feed hogs, said Goodson, Evonik’s manager of consulting services. But soybeans have a significant global warming potential, he said, when a person looks at the amount of carbon dioxide produced. Citing various literature sources, Goodson said the global warming potential for corn is about a 0.017 CO2 equivalent per kilogram, while it is a 0.721 equivalent per kilogram with soybeans.
Keeping that in mind, Goodson said it is clear that choosing a corn ration over a soybean-based ration would reduce the global warming potential. However, grain supplies may affect the type of commodities a feeder chooses.
But using a mix of synthetic amino acids can help feeders be more efficient and more environmentally friendly. “Swine, poultry and you do not require protein," said Goodson. "A lot of people think they do, but they don’t. They require amino acids."
When dietary protein is digested, it is mostly broken down into amino acids, he said. But the problem is that amino acids have to be present in exactly the right amount, at the right time for animals to make protein. If the correct amount of amino acid is not present at the right time, Goodson said, protein synthesis stops.
Feed ingredients do not typically provide the correct amounts of amino acids required for protein synthesis, so in order to meet the animal’s needs for muscle growth, without synthetic amino acids, producers have to overfeed.
When you overfeed protein to get those other amino acids, and they are broken down, that takes a lot of energy. Also, a major breakdown product of amino acid is nitrogen. Excessive nitrogen is particularly bad for chickens, he said, as it ends up forming ammonia. High levels of ammonia and wet litter can be very bad for the birds, especially if the nitrogen is up to 0.10 parts per million. Consequences of high nitrogen levels include causing the birds to become blind and develop lesions on their feet.
But adding synthetic amino acids such as methionine, threonine and valine can significantly improve feed efficiency, he said. Studies show that over a 50-day period, a bird weighing 7.3 pounds ate on average 14 pounds of feed.
He also showed, that with the proper mix of amino acids, a poultry processing plant that processes a million plants a week could see a net reduction of 185,000 kg of carbon dioxide global warming potential per week. “If you can reduce the global warming potential at one complex, that dramatically reduces your carbon footprint, and it really enhances sustainability,” said Goodson.