Chickens with Bigger Gizzards are More Efficient

Scientists from the French National Institute for Agricultural Research have been doing research on poultry production. They bred chickens to find out if larger digestive organs such as the proventriculus and the gizzard, would help to reduce the amount of wastes secreted by the chickens. The gizzard is an organ with thick muscular walls used to help break down food through mechanical digestion, while the proventriculus is a stomach-like organ with many acids and enzymes that break down food through chemical digestion. The researchers bred nine generations of chickens selecting for larger digestive organs, and discovered that chickens that had these larger organs ate less feed and produced less waste. This discovery will help to make poultry production more efficient and save money on chicken feed, as well as reduce the amount of pollutants released into the environment from chicken waste.

This article relates to the biology curriculum because it is based on the digestive system, which we learned about in class. For example, we talked about gizzards being present in some birds and other organisms, but not in humans. It is similar to human teeth in the digestive system, which also break down food with mechanical digestion. The proventriculus is like the human stomach which we studied, since it contains an acidic environment used for chemical digestion. Also, we learned that the more food is broken down, the more nutrients are absorbed into the small intestine. The undigested food continues into the large intestine and is excreted, which relates to the article since some chickens can digest food better than others, and subsequently produce less waste. Lastly, the study relates to earlier in the year, about selective breeding. The chickens with larger digestive organs are selected for, since they have an advantage of digesting more food, which helps poultry production become more efficient.

http://www.sciencedaily.com/releases/2013/04/130411110255.htm