Study to Determine a Baseline of Nitrogen Excretion from Broiler Chickens as it Relates to Ammonia Odor ProductionEPA Grant Number: R833150
Title: Study to Determine a Baseline of Nitrogen Excretion from Broiler Chickens as it Relates to Ammonia Odor Production
Investigators: Cherry, Tim , Jerez, Sheryll
Institution: Stephen F Austin State University
EPA Project Officer: Chung, Serena
Project Period: October 1, 2007 through September 30, 2010
Project Amount: $192,200
RFA: Targeted Research Grant (2007) Recipients Lists
Research Category: Targeted Research , Air Quality and Air Toxics
The objective of this project is to determine a baseline for the amount of nitrogen in commercial broiler facilities which has a direct correlation to the amount of ammonia released into the atmosphere. All incoming and outgoing sources of nitrogen will be monitored by weighing each source in kilograms for standard and low crude protein diets. From the data collected, a mass nitrogen balance will be calculated. The mass nitrogen balance will accurately calculate the amount of nitrogen (in the form of ammonia) that is released into the atmosphere for each treatment. The amount that cannot be directly measured will account for the nitrogen that has volatized in the atmosphere. The equation will then be extrapolated to determine a baseline for the amount of nitrogen that is released into the atmosphere per bird for a commercial broiler facility.
The study will be conducted over a standard five (5) flock commercial grow-out. Recycled litter will be utilized for each pen. At least three prior flocks will be reared on the same litter prior to the start of the study. No additional litter will be added between flocks. Approximately 6,400 broiler chicks will be placed into 48 – 10’ X 10’ pens, yielding a stocking density of 134 broiler chicks per pen. At study end, this will provide 0.75 square foot per bird. All incoming sources of nitrogen, chicks, existing litter, and feed, will be quantified by weight in kilograms and by analysis on a dry matter basis for moisture content and further analyzed by Elementar max carbon-nitrogen device for nitrogen content. All outgoing sources of nitrogen, carcasses, mortalities, caked litter, and ending litter will be quantified with the same procedures as the incoming sources of nitrogen. Nitrogen, in the form of ammonia, can be quantified by accounting for the above mentioned incoming and outgoing nitrogen sources. Caked litter will be removed between each flock. It will be weighed in kilograms after removal from each pen. The caked litter will then be disposed of according to the SFASU Poultry Research prior approved Nutrient Management Plan. Samples of the caked litter will be collected and analyzed on dry matter basis for moisture content. Further analysis will determine the nitrogen content through the use of an Elementar max CN analyzer. Ending litter will be weighed in kilograms by pen. A sample of the litter will be collected and analyzed with the same procedures as the caked litter. After weighing and sample collection, the litter will be returned to the same pen in which it was removed.
The results of this study will accurately indicate the amount of nitrogen that leaves broiler facilities via dust, ammonia, and particulate matter. It will eliminate the extrapolation of ammonia production which will decrease inaccuracies associated with previous ammonia production research. The results will aid in developing a marker for determining when ammonia production becomes excessive. Recent research indicates that results will vary amongst flocks, but there will be a distinguishable pattern within the difference. The research will focus on determining how low the protein level can be in a broiler diet and still achieve the desired weight gain and feed efficiency that is demanded in the broiler industry.