| title: |
Relationship between rumen degradable and soluble protein and the emission of excreted ammonia-nitrogen |
| reg no: |
ETF6052 |
| project type: |
Estonian Science Foundation research grant |
| status: |
accepted |
| institution: |
Institute of Animal Husbandry at EAU |
| head of project: |
Allan Kaasik |
| duration: |
01.01.2005 - 31.12.2008 |
| description: |
Depending of housing method nitrogen (N) emission as ammonia (NH3) from excreta of dairy cow (7000 kg milk per year) is about 3,5...10 kg per year.The nitrogen of urine is mainly in the composition of urea which is the main source of volatile ammonia. The urea in urine is one of the end products of N metabolism. According digestible physiology of ruminants the dietary protein is converted in the rumen to a protein which is available for the bacteria. Available for rumen bacteria is only that protein fraction which is soluble and degradable in rumen. The middle product of that process is ammonia that is not completely used by the bacteria in conditions of energy deficiency and is therefore absorbed trough the rumen epithelium to the blood. Since ammonia is recognised by the organism as a toxic component it is converted into urea in the kidney and excreted from the body with urine. Therefore there is tight relationship between the content of N in excreta (especially in urine) and degradability and solubility of dietary protein. The aim of the study is to investigate the influence of feedstuffs (legume and grass silage) with different content of soluble and degradable protein and saccharides (starch), as well as influence of protein feeds (rapeseed cake produced at different temperatures) and energy feeds (barley and corn) on the ammonia emission from excreta (urine) in dairy cows. |