Author
|
Submitted to: International Journal of Poultry Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/28/2016 Publication Date: 6/15/2016 Citation: Miles, D.M., Brooks, J.P., Moore Jr, P.A. 2016. Mid-flock and post-harvest spatial characterization of broiler litter gas flux and nutrients. International Journal of Poultry Science. 15(5):175-181. Interpretive Summary: The purpose of this work was to characterize the spatial variability of litter surface gas flux of ammonia, nitrous oxide, and carbon dioxide while making measurements of litter temperature, moisture content, pH, total nitrogen and total carbon from laboratory analyses. Two U. S. commercial broiler houses were intensively sampled along an imaginary grid for litter properties and gas flux on a farm in Mississippi (humid subtropical climate) where the original bedding material was pine wood shavings. Measurements were conducted before chicks were placed, during the middle of the flocks, and after birds were harvested. A greater degree of data variability resulted from measurements over time rather than between the houses. A good example is higher litter moisture near sidewalls during the post harvest measurement. All parameters were depicted as color contour plots; upper extremes for gas flux occurred between feeders and waterers. Tabular values cannot convey the complexity of litter surface characteristics and relationships. The efficacy of the data will be best derived by the user’s goal for improving bird productivity and management. Technical Abstract: The purpose of this work was to characterize the spatial variability of litter surface gas flux of NH3, N2O, and CO2 while making concurrent measurements of litter temperature and assessing litter moisture content, pH, total N and total C from laboratory analyses. Two U. S. commercial broiler houses were intensively sampled along an imaginary grid for litter properties and gas flux on a farm in Mississippi (humid subtropical climate) where the original bedding material was pine wood shavings. Before chicks were placed, the average gas flux from both houses was: 156 mg NH3m-2 h-1, 4.4 mg N2O m-2 h-1, and 6440 mg CO2 m-2 h-1. At mid-flock and after birds were harvested, pooled values from 44 locations resulted in: 260 mg NH3m-2 h-1, 13.1 mg N2O m-2 h-1, and 13100 mg CO2 m-2 h-1; and 260 mg NH3m-2 h-1, 13.1 mg N2O m-2 h-1, and 13100 mg CO2 m-2 h-1, respectively. A greater degree of data variability resulted from measurements over time rather than between the houses. A good example is higher litter moisture near sidewalls during the post harvest measurement. All parameters were depicted as color contour plots; upper extremes for gas flux occurred between feeders and waterers. Tabular values cannot convey the complexity of litter surface characteristics and relationships. The efficacy of the data will be best derived by the user’s goal for improving bird productivity and management. |
