Location: Food and Feed Safety Research
Title: Nitro-treatment of composted poultry litter, effects on Salmonella, E. coli and nitrogenAuthor
RUIZ-BARRERA, OSCAR - Universidad Autonoma De Chihuahua | |
ARZOLA-ALVAREZ, CLAUDIO - Universidad Autonoma De Chihuahua | |
CASTILLO-CASTILLO, YAMICELA - Universidad Autonoma De Ciudad Juarez | |
CORRAL-LUNA, AGUSTIN - Universidad Autonoma De Chihuahua | |
Anderson, Robin | |
Byrd Ii, James - Allen | |
Hume, Michael | |
Nisbet, David | |
SALINAS-CHAVIRA, JAIME - University Of Tamaulipas |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 4/3/2017 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Poultry litter is a potentially valuable crude protein feed for ruminants whose gut microbes transform the nitrogen in uric acid into microbial protein. However, poultry litter must be treated to kill pathogens before feeding. Composting effectively kills pathogens but risks volatilization losses of nitrogen as ammonia. Presently, 200-g portions of one year-old wood chip litter from non-antibiotic-treated birds were treated with ethyl nitroacetate (ENA) or 3-nitropropionate (3NPA) in 100 mL of 0.4 M phosphate buffer (pH 6.4) to achieve 25 micromol/g litter. Control litter was treated with buffer alone. The litter was distributed (11 g) to 50-mL tubes (9 tubes/treatment) and inoculated with a novobiocin and naladixic acid-resistant Salmonella Typhimurium (STNN) to achieve 3.0 log10 CFU/g. Tubes were capped, sealed with parafilm and incubated 6 days at 37 deg C and then 3 days at 50 deg C. Upon sampling (days 3, 6 and 9), 3 tubes of each treatment were diluted and plated on 3M E. coli/coliform petri-film and Brilliant Green Agar supplemented with 25 and 20 microg/mL novobiocin and naladixic acid, respectively, for enumeration of E. coli and STNN strain. Ammonia, uric acid, and urea were measured colorimetrically. Repeated measures analysis of variance revealed a main effect (P < 0.05) of treatment on STNN but not E. coli populations, with STNN being decreased > 1.0 log10 by nitro-treatment compared to controls (4.2 +/- 0.2 log10 CFU/g). A main effect due to days of incubation, reflecting an effect of composting, was observed on both STNN and E. coli, with populations decreasing to non-detectable levels by day 9. Interactions between treatment and day of incubation were not observed for STNN or E. coli. Main effects of treatment were observed on ammonia accumulations and uric acid degradation (P < 0.05), with 17 to 24% less ammonia accumulating in nitro-treated litter than controls (3.4 +/- 1.4 micromol/g) and 18% more uric acid remaining in 3NPA-treated litter than in controls or ENA-treated litter (18.1 +/- 3.8 micromol/g and 18.5 +/- 5.0 micromol/g, respectively). Accumulations of ammonia and urea increased (P < 0.05) due to day of incubation, the latter more rapidly (P < 0.05) during the early days of incubation in control litter than in 3-NPA- or ENA-treated litter (2.3 +/- 0.6, 1.5 +/- 0.4 and 0.5 +/- 0.6 micromol/g per h, respectively). Results suggest that nitro-treatment may help preserve uric acid in composted litter while aiding Salmonella control. |