The Effects of Acidification of Swine Waste on Bacterial Growth
School Name
South Carolina Governor's School for Science & Mathematics
Grade Level
12th Grade
Presentation Topic
Microbiology
Presentation Type
Mentored
Abstract
A fundamental issue of keeping pigs on farms is the disposal and maintenance of their waste. Typically funneled into a lagoon by spraying the waste through slates in the pigs’ quarters with water, this waste contains potentially harmful bacteria, including potentially antibiotic resistant strains. In addition to the risks of exposure, this waste is also used as fertilizer for food given to livestock. This waste is subjected to antibiotics, creating a dangerous selection for these antibiotic resistant traits. Based on research in European countries such as Denmark and Sweden, it was hypothesized that acidifying the waste could efficiently eliminate the bacteria. We attempted to determine the most effective pH and time of exposure for bacterial death. By adding sulfuric acid to liquified pig waste, we lowered the pH of the waste to pH 6, 4.5, 3, and 2. We collected samples zero, one, three, and twenty-four hours after acidification. For each experimental pH, we then incubated diluted samples on plates for approximately 24 hours. A pH of 2 resulted in the most bacteria death within three hours of acidification. The next step is to evaluate the cost of acidification for farmers based on the volume of their waste pond. This would enable the farmers to dispose of the waste in a safer and more profitable way. It also benefits the consumer, since antibiotic resistance could potentially be avoided.
Recommended Citation
Cimney, Kaitlyn, "The Effects of Acidification of Swine Waste on Bacterial Growth" (2019). South Carolina Junior Academy of Science. 258.
https://scholarexchange.furman.edu/scjas/2019/all/258
Location
Founders Hall 213 B
Start Date
3-30-2019 11:00 AM
Presentation Format
Oral Only
Group Project
No
The Effects of Acidification of Swine Waste on Bacterial Growth
Founders Hall 213 B
A fundamental issue of keeping pigs on farms is the disposal and maintenance of their waste. Typically funneled into a lagoon by spraying the waste through slates in the pigs’ quarters with water, this waste contains potentially harmful bacteria, including potentially antibiotic resistant strains. In addition to the risks of exposure, this waste is also used as fertilizer for food given to livestock. This waste is subjected to antibiotics, creating a dangerous selection for these antibiotic resistant traits. Based on research in European countries such as Denmark and Sweden, it was hypothesized that acidifying the waste could efficiently eliminate the bacteria. We attempted to determine the most effective pH and time of exposure for bacterial death. By adding sulfuric acid to liquified pig waste, we lowered the pH of the waste to pH 6, 4.5, 3, and 2. We collected samples zero, one, three, and twenty-four hours after acidification. For each experimental pH, we then incubated diluted samples on plates for approximately 24 hours. A pH of 2 resulted in the most bacteria death within three hours of acidification. The next step is to evaluate the cost of acidification for farmers based on the volume of their waste pond. This would enable the farmers to dispose of the waste in a safer and more profitable way. It also benefits the consumer, since antibiotic resistance could potentially be avoided.
