Ammonia loss from land-applied manure depends on weather conditions, manure characteristics, application technique and soil characteristics. Weather factors include temperature, rainfall, relative humidity and wind speed. Soil properties include moisture content, infiltration capacity, nutrient retention capacity, pH and soil chemistry. Manure characteristics affecting ammonia emissions include the ammonium concentration, pH and viscosity. The primary objective of an on-going research project at Brandon Research Centre is to develop ammonia emission factors for liquid swine manure under western Canadian conditions and practices. A secondary goal is to suggest methods (BMPs) for reducing emissions, particularly during periods when air quality is at risk. Since phosphorus accumulation in soils receiving manure is of concern due to increasing eutrification occurring in rivers and lakes, separating manures in order to improve the N:P ratio is under consideration as a method to improve phosphorus distribution. However chemicals added to enhance solids separation also alter the chemistry of manure and subsequently affect ammonia emissions from the liquids and solids after application. Accurate ammonia loss estimates from manure are needed to improve nutrient management recommendations and test the value of ammonia abatement techniques. Reliable measurements will assist in the development of emission calculation models to evaluate best cost, effective alternatives for reducing ammonia emissions. Many types of apparatuses have been developed for testing ammonia volatilization models to predict contributions to global livestock ammonia emissions. This study used wind tunnel measurements this technique has been identified as more suitable than small stationary chambers because temperature, humidity and natural airflow are more easily simulated. Wind tunnels can also be used on a small scale to compare multiple manure treatments and application techniques in a side-by-side analysis. This study concluded that under conditions of high air temperatures, a significant proportion of the ammonia nitrogen in manure could be lost from shallow banding or enhanced infiltration application techniques. Manure separation technologies that require the addition of alkaline flocculating agents could contribute to further ammonia losses by elevating the pH of both the liquid and the solid portion of the manure. The elevated pH increases nutrient loss and decreases the N:P ratio of the solid portion of the manure which may contribute to the phosphorus enrichment problem. Acidifying the liquids after solid-liquid separation should keep more of the ammonia in solution.