Submitted to: Prince Agri Products Feed Ingredient Conference
Publication Type: Proceedings
Publication Acceptance Date: 8/23/2000
Publication Date: N/A
Technical Abstract: Ruminant animals have developed a symbiotic relationship with ruminal microorganisms, and this interaction allows them to consume fibrous materials that would otherwise be indigestible. However, some ruminal bacteria can ferment amino acids, and ruminal protein degradation often produces excess ammonia. Excess ammonia diffuses across the rumen wall into oblood and is eventually converted to urinary urea. 15N experiments indicated that animals consuming fresh forage could waste as much as 50% of the feed protein. Ruminant nutritionists have sought methods for decreasing ammonia accumulation and improving nitrogen retention. Insoluble protein supplements can decrease ammonia production in the rumen, but these supplements are more expensive than natural proteins. Ammonia assimilation can be increased by adding starch to the ration, but rapid rates of starch fermentation can cause ruminal acidosis. The ruminal feed additive, monensin, decreased the ruminal ammonia concentration of cattle fed timoth hay, but it did not decrease ammonia when alfalfa hay was fed. Some ruminal bacteria produce bacteriocins that can inhibit other ruminal bacteria, and recent work indicates that these naturally occurring substances may have a positive impact on ruminal nitrogen metabolism.