The Effect of Mono- and Di-Saccharides on the Microbiome of Dairy Cow Manure and Its Odor.

In a previous experiment, we showed that the odor of manure slurries could be improved by anaerobic incubation with the sugars glucose, lactose, and sucrose. This improvement was due to reductions in the concentrations of malodorants, including dimethyl disulfide, -cresol, -ethylphenol, indole, and skatole, and a shift to the production of fruity esters, including ethyl butyrate and propyl propanoate. Due to large concentrations of lactic acid produced by the sugar-amended manure slurries, we inferred that lactic acid bacteria were involved in improving the manure slurry odor.

Microbiome Diversity of Anaerobic Digesters Is Enhanced by Microaeration and Low Frequency Sound.

Biogas is produced by a consortium of bacteria and archaea. We studied how the microbiome of poultry litter digestate was affected by time and treatments that enhanced biogas production. The microbiome was analyzed at six, 23, and 42 weeks of incubation.

Effect of continuous in-feed administration of tylosin to feedlot cattle on macrolide and tetracycline resistant enterococci in a randomized field trial.

Liver abscess causes substantial economic loss to the beef cattle industry through liver condemnation, reduced animal performance, and carcass yield. Continuous in-feed use of tylosin is the most effective and a commonly used practice in beef cattle production to prevent liver abscess. However, such mass medication can increase the level of antimicrobial resistant bacteria.

Lagoon, Anaerobic Digestion, and Composting of Animal Manure Treatments Impact on Tetracycline Resistance Genes.

Increased demand for animal protein is met by increased food animal production resulting in large quantities of manure. Animal producers, therefore, need sustainable agricultural practices to protect environmental health. Large quantities of antimicrobials are used in commercial food animal production.

Anaerobic Digestion of Tetracycline Spiked Livestock Manure and Poultry Litter Increased the Abundances of Antibiotic and Heavy Metal Resistance Genes.

Anaerobic digestion is used for the treatment of animal manure by generating biogas. Heavy metals cause environmental pollutions and co-select for antimicrobial resistance. We evaluated the impact of mesophilic anaerobic digestion of cattle manure (CM), swine manure (SM) and poultry litter (PL) on the concentrations of seven tetracycline [(A), (B), (G), (M), (O), (Q), and (W)], macrolide [(B)], methicillin (A and C), copper (B, A, D, and B) and zinc (C) resistance genes, and three bacterial species (, spp.

Anaerobic digestion of livestock and poultry manures spiked with tetracycline antibiotics.

We investigated the anaerobic degradation of tetracycline antibiotics (tetracycline [TC], oxytetracycline [OTC] and chlortetracycline [CTC]) in swine, cattle, and poultry manures. The manures were anaerobically digested inside polyvinyl chloride batch reactors for 64 days at room temperature. The degradation rate constants and half-lives of the parent tetracyclines were determined following first-order kinetics.

Abundances of Tetracycline Resistance Genes and Tetracycline Antibiotics during Anaerobic Digestion of Swine Waste.

The impact of anaerobic digestion of animal waste on the persistence of antibiotic resistance genes (ARGs) and antibiotics is not widely studied. Two identical, 800-L digesters seeded with swine slurry were followed up to 100 d in three separate trials. The trials received varying amounts of antibiotic-free corn ( L.

Improved water quality and reduction of odorous compounds in anaerobic lagoon columns receiving pre-treated pig wastewater.

Large volumes of wastewater from confined pig production are stored in anaerobic lagoons. Control methods are needed to reduce air pollution by foul odors released from these lagoons. In a pilot-scale experiment, we evaluated the effect of pig wastewater pre-treatment on reducing the concentration of selected malodor compounds in lagoons receiving liquid from: (1) flocculant enhanced solid-liquid separation (SS), and (2) solid-liquid separation plus biological N treatment using nitrification-denitrification (SS+NDN).

Evaluation of second-generation multistage wastewater treatment system for the removal of malodors from liquid swine waste.

Wastewater quality and malodors in a second generation implementation of environmentally superior technology (EST) were monitored over three cycles of pig (Sus scrofa) production and 15 mo. The wastewater treatment system consisted of three modules: solids separation, biological N removal, and P recovery/wastewater disinfection. While approximately more than 90% of the wastewater suspended solids were removed in the first stage of treatment, little reduction in malodorous compounds occurred, indicating that malodors largely remained with the liquid waste stream.

Spatial and temporal changes in the microbial community in an anaerobic swine waste treatment lagoon.

Microorganisms are central to both the beneficial (organic degradation, nutrient removal, biogas production) and detrimental (odor production, pathogen contamination) effects of swine waste storage systems. In this study, both quantitative (real-time polymerase chain reaction) and qualitative (denaturing gradient gel electrophoresis, cloning, sequence analysis) molecular analyses were used to track spatial and temporal changes in the microbial community of swine slurry from a 0.4 ha anaerobic lagoon.

Development of a second-generation environmentally superior technology for treatment of swine manure in the USA.

New swine waste management systems in North Carolina need to meet high performance standards of an environmentally superior technology (EST) regarding nitrogen, phosphorus, heavy metals, pathogens, ammonia and odor emissions, and remain affordable and simple to operate. The objective of this study was to develop a second-generation treatment system that can achieve high EST standards at reduced costs. The system used solids separation, nitrification/denitrification and phosphorus removal/disinfection, and was demonstrated at full-scale on a 5145-head swine farm during three production cycles (15-months).

The effect of stratification and seasonal variability on the profile of an anaerobic swine waste treatment lagoon.

In this study, the characterization of an anaerobic swine waste treatment lagoon from a farrowing operation (approximately 2000 sows) was carried out to examine the dynamics of the system due to stratification and seasonal variability. Swine waste samples were taken at different depths with a pulley system equipped with a special sampler that allows for sampling exclusively at certain depth. Chemicals and microbial dynamics were monitored throughout a one-year-period.

Equilibrium sampling used to monitor malodors in a Swine waste lagoon.

The concentrations of malodorous compounds in a 0.4-ha anaerobic lagoon that received waste from approximately 2000 sows were monitored during the late summer to late fall of 2006 to gain insight into the factors influencing their concentrations. Selected malodorous compounds were measured by the use of equilibrium samplers consisting of submersible stir plates and stir bar sorbtive sampling with polydimethylsiloxane-coated magnetic stir bars.

Characterization of skatole-producing microbial populations in enriched swine lagoon slurry.

Skatole is one of the most malodorous compounds produced from the anaerobic degradation of animal waste. Little is known about the biochemistry of skatole production, the phylogeny of skatole-producing microorganisms or the conditions that favor their growth. These deficiencies hamper attempts to reduce skatole production.

Comparison of solid-phase microextraction and stir bar sorptive extraction for the quantification of malodors in wastewater.

Malodors in wastewater from animal-rearing facilities are due to the presence of characteristic polar compounds. The efficiency and reproducibility of three solid-phase microextraction (SPME) fibers (Carboxen-PDMS, polyacrylate, and PDMS) as well as PDMS-coated stir bars for the measurement of some of these compounds in the liquid phase were compared. In initial experiments, the SPME fibers and stir bars were exposed to a standard water solution containing a mixture of 18 compounds with a range of octanol-water partition coefficients.

Free Fatty acids and sterols in swine manure.

Free fatty acids and sterols were assessed in fresh manure and anaerobic lagoon sludge from swine production facilities in North Carolina. Eight free fatty acids and five sterols were identified and quantified in both manure and sludge samples. Compound identification was performed by gas chromatography/mass spectroscopy (GC-MS), and compound quantities were determined by gas chromatography after solid phase extraction with a 50:50 mixture of diethyl ether and hexane.

Reduction of malodorous compounds from a treated swine anaerobic lagoon.

There is a need for treatment technologies that can eliminate environmental problems associated with anaerobic lagoons. These technologies must be able to capture nutrients, kill pathogens, and reduce emissions of ammonia and nuisance odors. To meet these needs, a full-scale wastewater treatment plant was installed as a demonstration project on one of three 4360-pig (Sus scrofa) production units in a finishing farm in Duplin County, North Carolina.

Aroma content of fresh basil (Ocimum basilicum L.) leaves is affected by light reflected from colored mulches.

Sweet basil (Ocimum basilicum L.) is an herb that is used to add a distinct aroma and flavor to food. Volatile compounds emitted from fully expanded fresh leaves grown in drip-irrigated plots that were covered with six colors of mulch were compared.

Aroma of fresh strawberries is enhanced by ripening over red versus black mulch.

Strawberry (Fragaria ananassa Duch) is a high-value food crop, the aroma of which is important in consumer satisfaction. We hypothesized that the concentration of fresh strawberry aroma compounds could be enhanced by growing the berries over a red plastic mulch that was formulated to reflect more far-red (FR) and red light (R) and a higher FR/R photon ratio than is reflected by standard black plastic mulch. Strawberries of the cultivars "Chandler" and "Sweet Charlie" were grown in trickle-irrigated field plots over the two colors of mulch.