Developing and Evaluating an Innovative Litter Amendment Application System for Poultry Operations

<p>NON-TECHNICAL SUMMARY:<br/>This research project aims at developing and evaluating an innovative mitigation technology to reduce reactive nitrogen (ammonia) emission from poultry feeding operations, conserve nitrogen in poultry litter and increase its fertilizer value, and improve animal welfare, health and production. The project will focus on accomplishing the following objectives: 1) to develop an automated application system (AAS) in broiler houses for acid-based litter amendments under field conditions; 2) to evaluate and delineate the efficacy of various amendments and application rates/intervals on air emissions and animal health; 3) to conduct field verification tests in two commercial poultry houses and economic analysis on acid-based litter amendments regarding production performance, microbial communities, and air emissions over an extended period; and 4) to
investigate and characterize the microbial environment of treated poultry litter with AAS emphasizing specific microbiological agents that impact broiler chicken health and ammonia formation. The knowledge and technology developed will contribute to effective air emission abatement for the protection of the environment and human health, and the conservation of nitrogen to contribute to the economic competitiveness of the animal industry. The results of the project have the potential for nationwide application. The longer-term outcome is attaining the goal of an environmentally sustainable animal production system.<p>
APPROACH: <br/>For objective 1, a prototype of AAS will be designed and fabricated based on findings from our preliminary study. The prototype will be installed in an empty broiler house. An empirical model of distribution uniformity of the granular materials delivered by the system, as affected by key design and operating parameters will be developed in a two-step process using data acquired through tests with the prototype. Based on the empirical model developed using the prototype, two full-scale AAS with multiple spreaders will be designed for a 60 x 500 ft (width x length) commercial broiler house and a 37 x 57 ft research broiler house, which will be used in Objective 3 to verify the performance of the system under field conditions. A 3-D simulation model will be established and calibrated through comparisons of particle trajectory simulations to experimental
tests. For objective 2, three commercially available products will be evaluated. They include Al+ Clear , PLT, and Klasp which are already widely used by broiler and turkey operations for the brooding period. The test will be conducted using six environmentally-controlled emission chambers (EC) and emission rooms (ER). Gaseous emission, production performance data for birds from each chamber, including feed consumption, body weight, and feed efficiency, will be collected. For objective 3, One litter amendment and application rates and intervals identified as described in Objective 2 will be tested further to determine air emission reduction, production performance, and litter quality under field conditions at a commercial broiler farm managed by the University of Maryland Eastern Shore and at the University of Delaware research farm. A paired comparison will be conducted for both sites.
The two identical commercial houses on the commercial site have dimensions of 500 ft x 60 ft (150 m x 18 m) each and a holding capacity of approximate 35,000 broiler bird. The university research house, measuring 114 ft x 37 ft (34.6 m x 12.1 m), is divided into two partitions, 57 ft x 37 ft (17.3 m x 12.1 m) each. The two partitions (2000birds/partition) are identical and share the same end wall and control room. For objective 4, used litter from a commercial broiler farm and new bedding (wood shaving) will be used to mixed with PLT. Effects of the treatments on microorganisms will be assessed by total aerobic plate counts and by counts of coliform bacteria. To evaluate the effect of treatments on ammonia-producing microbial populations and urease activity in the litter, a q-PCR-based method and urease activity detection method will be used. To extend our understanding of the litter
microbiome, we will conduct a metagenomic analysis of the DNA samples using Illumina high-throughput sequencing.</p>