Amino acids in plants are upgraded through cattle, but the amount depends on the production system
The animal article of the month for March is entitled “Upgrading plant amino acids through cattle to improve the nutritional value for humans – effects of different production systems“. Authors: M. Patel, U. Sonesson and A. Hessle
Cattle have a unique ability to digest fibrous materials, so they can make use of feedstuffs that are not suitable as human food, e.g. by-products from the food and biofuel industry. Milk and beef can also be produced from marginal land that is not useful for crop production, from permanent grassland or in areas where grass production is more viable than cropping. In light of the increasing global population and the limited possibilities to increase the area of arable land on Earth, it is important to consider all available resources for producing food.
In a recent study, we examined the content of human-digestible essential amino acids (HDEAA) in the feeds we currently use for cattle and compared it to the content in the products that cattle produce, i.e. milk and meat. We theoretically examined different systems for milk and beef production that could be applied in Sweden, a country with high-yielding dairy cows and where the climate is temperate to cool, giving a rather short growing season. We compared feed rations that included cereal grains and pulses to rations based on by-products and with a high proportion of grass or maize silage, in both intensive and extensive production systems. In general, we found that the quantity of HDEAA in the products from the dairy systems exceeded the quantity in the feeds, particularly in an extensive system with low inputs of grain and in an intensive system based on grass and maize silage. In beef production, an intensive system with calves originating from dairy cows generated less HDEAA in the products compared with the feeds, because the calves needed a milk replacer and concentrates, whereas in an extensive system with calves from suckler cows the HDEAA in the products exceeded the quantity in the feeds.
The results clearly reflected the amount of forage in the ration, but also the assumptions made on the human-edible fraction of the feed. A sensitivity analysis revealed that this was the main factor affecting the results in intensive production, where a large proportion of the ration consisted of by-products or cereal grains. Researchers need to agree a standard definition of the human-edible fraction in feeds when studying next-generation cattle production systems, because forage and human-inedible feeds are key to efficiency in future milk and beef production.
This article is freely available for one month: Upgrading plant amino acids through cattle to improve the nutritional value for humans – effects of different production systems
Authors: M. Patel, U. Sonesson and A. Hessle
The animal Article of the Month is selected by the Editor-in-Chief and is freely available for one month. View the recent selections