Date of Graduation
7-2025
Document Type
Thesis
Degree Name
Bachelor of Science in Agriculture
Degree Level
Undergraduate
Department
Agricultural Economics and Agribusiness
Advisor/Mentor
Popp, Michael
Committee Member
Thompson, Jada
Second Committee Member
Liang, Yi
Abstract
Poultry litter varies widely in nutrient content. Statistical analysis of litter sample data was conducted: i) to determine how nutrient concentration mean and variance obtained from replicate nutrient sampling from fifteen different litter sources translates to mean and variance in nutrient content of ten litter blends each from two, four or six randomly selected sources; and ii) to assess how the average and variance of replicate sample mean and variance of nutrient content across the fifteen litter sources compare to their counterpart of ten 2-way, ten 4-way and ten 6-way litter blends. Should i) the average of nutrient content across blended litters not differ from the average of the initial sources, and ii) the variation in nutrient content across blended litters decline in comparison to variation in nutrient content observed across the initial sources, then blending of litters would add value to litter to enhance the likelihood of transporting litter further form their source. Insights on how many initial sources of litter to use in blends to minimize nutrient content variation could also be observed. To that end, fifteen different 5-gallon buckets of poultry litter were collected from UA farms growing broiler chicken and breeder hens. Several 10-oz subsamples from the initial poultry litter sources were blended from randomly chosen two-way, four-way or six-way mixtures to create 120-oz mixtures. Those mixtures were exposed to the same length of mixing time in a cement mixer to assess whether blending from two, four, or six sources would impact deviations from expected average and variance of nutrient content calculated from the parent sources. Each of the fifteen poultry sources were sampled four times each to arrive at mean/variance estimates of the parent sources. Each of the ten randomly chosen combinations of two-way, four-way, six-way mixtures were also sampled three times each to arrive at mean/variance estimates of the mixtures. Results suggested that mixing significantly reduced nutrient concentration variance across the three sets of mixtures while leaving mean nutrient concentrations unaltered. Examining the range of mean nutrients across mixtures in comparison to the range in mean nutrient concentration of the initial sources suggested that minimum range in mean nutrient concentration is achievable when randomly sourcing from four to six sources pending nutrient targeted. This supports the potential practice of litter blending. Prediction of range of within mixture standard deviation of nutrient concentrations lead to less statistically significant findings as the range of standard deviation within mixtures changed very little as a result of blending. Considering small sample sizes and a three-minute mixing interval in a cement mixer, further experimentation may need to be conducted to better understand blending effects of poultry litters and how results might translate to larger batches of poultry litter mixtures.
Keywords
poultry; poultry science; litter; waste management; mixing; blending
Citation
Marchant, M. C., & Popp, M. (2025). Poultry Litter Blending as a Means for Managing Nutrient Content and Variation. Agricultural Economics and Agribusiness Undergraduate Honors Theses Retrieved from https://scholarworks.uark.edu/aeabuht/36
