Ruminants have microbes in their rumen that degrade most dietary proteins into ammonia, which microbes use to grow. However, high-yielding animals like dairy cows require high-quality proteins that should reach the small intestine undigested by microbes. This fraction is called bypass protein or undegradable intake protein (UIP). To increase bypass protein, feed can be heat-treated (like roasting soybean), or chemically treated (e.g., with formaldehyde). Bypass protein improves milk production, growth, and reproductive efficiency.