Location: Livestock Bio-SystemsTitle: Production of greenhouse gases, ammonia, hydrogen sulfide, and odorous volatile organic compounds from manure of beef feedlot cattle implanted with anabolic steroids
|Hales Paxton, Kristin|
Submitted to: Waste to Worth Conference
Publication Type: Proceedings
Publication Acceptance Date: 3/1/2019
Publication Date: 4/1/2019
Citation: Spiehs, M.J., Woodbury, B.L., Hales, K.E. 2019. Production of greenhouse gases, ammonia, hydrogen sulfide, and odorous volatile organic compounds from manure of beef feedlot cattle implanted with anabolic steroids. In: Proceedings of Waste to Worth Conference, April 22-26, 2019, Minneapolis, Minnesota. Available: https://lpelc.org/production-of-greenhouse-gases-ammonia-hydrogen-sulfide-and-odorous-volatile-organic-compounds-from-manure-of-beef-feedlot-cattle-implanted-with-anabolic-steroids/
Technical Abstract: Animal production is part of a larger agricultural nutrient recycling system that includes soil, water, plants, animals and livestock excreta. When inefficient storage or utilization of nutrients occurs, parts of this cycle become overloaded. The U.S. Beef industry has made great strides in improving production efficiency with a significant emphasis on improving feed efficiency. Improved feed efficiency results in fewer excreted nutrients and odorous volatile organic compounds (VOCs) that impair environmental quality. Anabolic steroids are used to improve nutrient feed efficiency which increases nitrogen retention and reduces nitrogen excretion. This study was conducted to determine the methane (CH4), carbon dioxide (CO2), nitrous oxide (N2O), VOC, ammonia (NH3), and hydrogen sulfide (H2S) production from beef cattle manure and urine when aggressive steroid implants strategies were used instead of moderate implant strategies. Urine and feces samples were collected individually from 60 animals that received a moderate implant and 60 animals that received an aggressive implant at each of three sampling dates (Spring and Fall 2017 and Spring 2018). Within in each treatment, fresh urine and feces from five animals were mixed together to make a composite sample slurry (2:1 ratio of manure:urine) and placed in a petri dish. There were seven composite mixtures for each treatment at each sampling date. Wind tunnels were used to measure gas emissions. Odorous VOC were measured using sorbent tubes. Flux of NH3 (2489.7 ± 53.0 vs. 2186.4 ± 46.2 mg m-2 min-1), H2S (4.0 ± 0.1 vs. 2.7 ± 0.2 µg m-2 min-1), CH4 (117.9 ± 4.0 vs. 104.0 ± 3.8 mg m-2 min-1), N2O (8.6 ± 0.1 vs. 7.4 ± 0.1 mg m-2 min-1), and total aromatic VOCs (2.9 ± 0.3 vs. 2.1 ± 0.2 mg m-2 min-1), were significantly higher from manure of cattle given a moderate implant compared to an aggressive implant, respectively. However, the flux of total branched-chained VOCs (5.9 ± 0.5 vs. 7.6 ± 0.8 mg m-2 min-1), from the manure was lower for cattle implanted with moderate implants compared to aggressive implants. Overall, this study suggests that air quality may be improved when an aggressive implant is used in beef feedlot animals.