Masters Theses

Date of Award


Degree Type


Degree Name

Master of Science


Biosystems Engineering Technology

Major Professor

Dr. Robert T. Burns

Committee Members

Dr. Ann Draughon, Dr. Forbes Walker, Dr. Luther Wilhelm


Dry granular alum (aluminum sulfate) has been used effectively as a broiler litter amendment to reduce ammonia (NH3) volatilization in broiler production houses. Some broiler producers are currently using liquid alum, but no published information is available concerning its use in treating broiler litter. Likewise, information has not been published on the use of liquid alum to reduce Salmonella and Campylobacter. The three goals of this project were to enumerate and test the survival of Salmonella and Campylobacter in four commercial broiler production houses, compare in-house ammonia levels with four different liquid alum treatments, and compare two ammonia emissions estimate methods in a broiler house: a nitrogen mass-balance approach and a flow-integration approach. This project investigated four treatment levels of liquid aluminum sulfate (Al+Clear® Liquid Alum, General Chemical Corporation, Parsippany, New Jersey) in four adjacent broiler production houses of the same design. The houses were treated with the following rates of liquid alum: 0, 0.82, 1.64, and 2.46 L m-2. These rates are equivalent to 0, 45, 90, and 135 kg of dry aluminum sulfate per 93 m2 of production unit floor area on an aluminum sulfate basis. Each broiler house contained approximately 30,000 birds with a six-week grow-out period per flock. There were approximately two weeks between harvest of birds and introduction of the next flock when the houses were empty. The study was conducted over an 18-month period, and eight flocks of broilers were grown in each house. v Pathogen Component Pathogen sampling events for each grow-out occurred at the beginning of the grow-out and 21 d after alum application. Four composite litter samples were collected for each sample event. Modified Food and Drug Administration (FDA) and United States Department of Agriculture (USDA) methods were used to detect and enumerate Aerobic Plate Counts (APCs), coliforms, Salmonella and Campylobacter in the litter samples (AOAC, 1998). All isolates were confirmed biochemically and serologically. Data are reported for 15 sample events (2002- 2003 production year). In all four broiler houses, there was a decreasing trend over 12 months in Salmonella levels when compared to pre-treatment (baseline) bacteria levels. Salmonella levels increased within individual grow-outs in each of the houses during the study. There was a negative correlation between levels of Salmonella and litter pH when litter pH was reduced below 3.5. Campylobacter was detected for four months during the study in house 1, 2, and 4. The 1.64 L m-2 alum application rate reduced Campylobacter levels by log 0.94 CFU ml-1 and the 0.82 L m-2 rate reduced Campylobacter levels by log 3.5 CFU ml-1. In the three alum-treated houses, coliform levels were reduced when compared to baseline levels. In the control house, coliform levels increased when compared to baseline levels. Liquid alum did not reduce APCs over the production period. These research findings suggest that the use of alum can reduce Salmonella, Campylobacter, and coliforms over a 12-month period in a poultry broiler production facility. vi In-house NH3 Concentrations Component In the four units, in-house gaseous ammonia levels were measured every 5 s using Dräger Polytron I electrochemical gas sensors. Data are reported on four flocks of birds (October 2002 – May 2003). The 0.82 L m-2 application rate was effective at maintaining in-house NH3 concentrations below 25 ppm for the first two weeks of the grow-out. Both the 1.64 L m-2 and 2.46 L m-2 rates were effective in keeping in-house NH3 levels below 25 ppm for the first three weeks of the grow-out. Ammonia Emissions Component Total nitrogen inputs (bedding shavings, new birds, and feed) and outputs (broilers and litter) were used to arrive at the mass-balance ammonia emission estimate. The difference between nitrogen inputs and outputs was assumed to be volatilized nitrogen. In addition, a flow-integration emission estimate was determined by collecting house 4 NH3 concentrations and exhaust fan flow-rate data every 5 s for 168 d (four flocks of birds). The nitrogen mass-balance estimate was calculated as 9754 kg NH3 yr – 1house-1. The flow-integrated method yielded an NH3 emission estimate of 9161 kg NH3 yr –1house-1, within 6% of the mass-balance approach. Both methods resulted in an average daily NH3 emission factor of 17 g hr –1 500 kg bird mass-1. Using the flow-integration method, the maximum NH3 emission rate was 61 kg d-1 house-1 and the average NH3 emission rate was 28 kg d-1 house-1. Mass-balance methods appear to be a useful technique for providing accurate long-term (e.g. year) NH3 emission estimates from poultry broiler production units. The flowvii integrated approach with carefully designed ammonia measurement equipment can supply short-term (e.g. days, weeks) NH3 emission factors.

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