Date of Graduation


Document Type


Degree Type



Davis College of Agriculture, Natural Resources and Design


Animal and Nutritional Sciences

Committee Chair

Joseph S. Moritz

Committee Co-Chair

Jacek Jaczynski

Committee Member

Jacek Jaczynski

Committee Member

Cangliang Shen


Experiments were conducted to evaluate how differing feed manufacture techniques, such as varying conditioning times and new equipment, can affect pathogen mitigation, feed manufacture metrics, amino acid digestibility, and enzyme recovery in feed. Feed hygienics are of increasing importance in providing safe feed to animals, and ultimately safe food for consumers. Salmonella has been identified as a major microbial hazard in animal feed that has been linked to animal and human illness. In chapter 2, the effects of standard pelleting and more thermally aggressive techniques were utilized to determine pathogen mitigation potential. Use of antibiotics has decreased in recent years due to policies and practices of poultry production, increasing opportunities for potential pathogens in feed to affect poultry and poultry products. More thermally aggressive pelleting decreased pellet mill motor load (P=0.02), increased hot pellet temperature (P=0.02), and tended to increase pellet durability (P=0.07). E. faecium ATCC 8459, as a Salmonella surrogate colonies were reduced with standard pelleting relative to inoculated mash and reduced further with more thermally aggressive pelleting (PE. faecium ATCC 8459 colonies respectively, relative to inoculated mash. In chapter 3, varying steam conditioning temperature and conditioning time were utilized to examine the how these interacted to affect pellet mill motor load, pellet quality, digestible amino acid concentration, and enzyme recovery. Corn and soybean meal based diets that included DDGS and meat and bone meal were conditioned at either 76°C, 82°C, or 88°C with conditioning times of either 30 or 60 seconds. Conditioning temperature and time interacted to affect pellet mill motor load (P