@article{shah_oviedo-rondon_grimes_westerman_campeau_2013, title={Acidifier dosage effects on inside ammonia concentrations in roaster houses}, volume={29}, DOI={10.13031/aea.29.9904}, abstractNote={Abstract. Ammonia (NH 3 ) in broiler houses can degrade bird performance. Acidifier such as, sodium bisulfate (SBS) applied to litter inside broiler houses can reduce NH 3 release and thus improve bird performance. While there are multiple studies on acidifier effects on inside NH 3 concentrations in broiler houses, there are no studies in roaster houses where big broiler birds are grown for 8 to 12 wk. The impact of different SBS application rates - High (1.46 kg/m 2 , whole house), Medium (0.73 kg/m 2 , whole house), Low (0.49 kg/m 2 , whole house), and Control (0.49 kg/m 2 , brood chamber) on inside NH 3 concentrations was evaluated over six flocks of roaster chickens (~4 kg ea.). Ammonia concentrations were measured with acid scrubbers that sampled air at two locations (mid-house, end-house) 0.15 m above the litter. Inside NH 3 concentrations were much higher in the cool-season versus warm-season flocks. Generally, higher acidifier application rates provided better NH 3 suppression. Ammonia concentrations were ≤10 ppm during brooding, as well as for the entire duration of most warm-weather flocks with the High and Medium treatments. In the Low treatment, NH 3 concentrations were ≤25 ppm during brooding but approached or exceeded 25 ppm with the Control treatment. During brooding, the High, Medium, and Low treatments resulted in significantly lower mid-house NH 3 concentrations of 3, 6, and 14 ppm, respectively, versus the Control treatment (24 ppm). For a 62-d flock, mid-house NH 3 concentrations were significantly lower in the High and Medium treatments versus the Control treatment; concentrations in the High, Medium, and Low treatments were reduced by 47%, 32%, and 20%, respectively, versus the Control treatment.}, number={4}, journal={Applied Engineering in Agriculture}, author={Shah, Sanjay and Oviedo-Rondon, E. O. and Grimes, J. L. and Westerman, P. W. and Campeau, D.}, year={2013}, pages={573–580} }
 @article{shah_westerman_grimes_oviedo-rondon_campeau_2013, title={Ancillary effects of different acidifier application rates in roaster houses}, volume={22}, ISSN={1056-6171 1537-0437}, url={http://dx.doi.org/10.3382/japr.2012-00693}, DOI={10.3382/japr.2012-00693}, abstractNote={SUMMARY High ammonia levels in broiler houses can reduce bird performance. Broiler producers commonly use acidifiers to reduce ammonia build-up. In addition to improving broiler performance, acidifiers can also provide other ancillary benefits such as reducing propane and electricity use and increasing cake (caked litter) N content. In this 2-yr study involving 9 flocks, 4 levels of an acidifier (sodium bisulfate) were applied to commercial roaster houses in eastern North Carolina. The control treatment had a sodium bisulfate application rate of up to 0.1 lb/ft2 to the brood chamber, whereas the high, medium, and low treatments had application rates of up to 0.3, 0.15, and 0.1 lb/ft2, respectively, to the whole house. No treatment effect was observed on propane or electricity use. However, compared with published studies involving smaller broilers, roasters required lesser amounts of propane and electricity. Linear regressions of propane and electricity use as a function of ambient temperature may help with decision making in roaster production. Brooding accounted for 88% of propane consumption. Reduced pH in the high treatment compared with the other treatments led to significantly higher ammonium concentration in the cake.}, number={3}, journal={The Journal of Applied Poultry Research}, publisher={Oxford University Press (OUP)}, author={Shah, S. B. and Westerman, P. W. and Grimes, J. L. and Oviedo-Rondon, E. O. and Campeau, D.}, year={2013}, month={Sep}, pages={565–573} }
 @article{shah_grimes_oviedo-rondon_westerman_campeau_2013, title={Nitrogen mass balance in commercial roaster houses receiving different acidifier application rates}, volume={22}, ISSN={["1537-0437"]}, DOI={10.3382/japr.2012-00704}, abstractNote={SUMMARY Broiler production has the potential to cause water and air pollution. Acidifiers such as sodium bisulfate (SBS) can reduce ammonia (NH3) emissions from broiler houses; NH3 is an important air pollutant that also affects bird health. Due to their longer grow-outs, roasters may require higher acidifier application rates to prevent unhealthy NH3 levels during the flock than ordinary broilers. Changes in NH3 emission with acidifier use may affect the partitioning of the input nitrogen (N) among the different N output pathways. Accounting for these output pathways through N mass balance provides a complete picture of N as it cycles through the roaster house. In a 2-yr study involving 9 flocks of roasters, 4 levels of SBS were applied to the litter in commercial roaster houses. Whereas the control treatment received up to 0.49 kg/ m 2 to the brood chamber, the high, medium, and low treatments received up to 1.46, 0.73, and 0.49 kg/m 2 , respectively, to the whole house. Ammonia-N emission decreased and N removed in cake and litter increased with SBS application rate. Nitrogen output components were averaged over the 4 treatments and expressed as percent of total N input or per unit mass of live weight (LW). Ammonia-N emission during grow-out, bird N exported, and cake and litter N removed accounted for 17.3% or 11.2 g/kg of LW, 38.9% or 25.1 g/kg of LW, and 22.4% or 14.4 g/kg of LW, respectively. We accounted for 79.1% of the total N inputs, with NH3-N losses during layout probably constituting the bulk of the unaccounted N. In addition to uncertainties in measurements of inputs and outputs, other factors that limited the ability to close the N mass balance were exclusion of feathers during cake and litter sampling, soil N leaching, and nitrous oxide emissions.}, number={3}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, author={Shah, S. B. and Grimes, J. L. and Oviedo-Rondon, E. O. and Westerman, P. W. and Campeau, D.}, year={2013}, month={Sep}, pages={539–550} }