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Foam accumulation in deep-pit manure storages is an increasing concern for swine producers because of the logistical and safety-related problems it creates. To investigate this phenomenon, samples of swine manure were collected over a 13-month period from 58 swine production facilities in Iowa with varying levels of foam accumulation. Samples were tested for a number of physical, chemical, and biological parameters including pH, total and volatile solids, volatile fatty acid concentration, long-chain free fatty acid concentration, biochemical methane potential, methane production rate, surface tension, foaming capacity, and foam stability. Statistical analysis indicated that manure collected from facilities with foam accumulation produced methane at significantly (p < 0.05) faster rates than non-foaming manures (0.148 ±0.004 and 0.049 ±0.003 L CH4 L-1 slurry d-1, respectively) and consequently had significantly (p < 0.05) greater fluxes of biogas moving through the manure. The biochemical methane production assay suggested that manure from foaming pits had less potential to generate methane (123 ±9 mL CH4 g-1 VS) than manure from non-foaming pits (150 ±9 mL CH4 g-1 VS), presumably because more of the methane potential had previously been consumed, as indicated by the higher methane production rates. Short-chain fatty acid concentrations were significantly lower in foaming manures (4200 ±570 mg kg-1) than nonfoaming manures (9470 ±730 mg kg-1). The methane production rate, biochemical methane potential, and short-chain fatty acid assays suggest enhanced anaerobic digestion efficiency from foaming barns as compared to non-foaming barns. Other assays, such as surface tension and foaming capacity, indicated an accumulation of a surfactant at the manure-air interface of the foam, which may be capturing biogas bubbles generated within the manure. Most importantly, the foam layers exhibited a greatly enhanced ability to stabilize bubbles, which appeared to be correlated to the higher solids concentrations that stabilize the bubbles. [ABSTRACT FROM AUTHOR]

Sulfur is a key nutrient associated of H2S emission and associated with both odor emissions and respiratory distress of animals. Due to potential increases in S levels in swine diets, two experiments were conducted to determine the effect of dietary S level and source on manure slurries chemical properties and gas emissions. Experiment 1 investigated the effects of increasing dietary S level while Exp. 2 evaluated the source of increased dietary S. In Exp. 1, 24 gilts averaging 152 kg BW were fed four different diets ranging between 1,800 and 6,000 mg/kg total S, as supplied by CaSO4, with an ADFI of 3.034 kg/d over the 31 d trial. In Exp. 2, 24 gilts averaging 139 kg BW were fed a diet containing either 1,800 mg/kg total S or diets containing 3,500 mg S/kg diet as supplied by CaSO4, distillers dried grains with solubles (DDGS), or feather meal (FM) with an ADFI of 2.705 kg/d over the 41 d trial. In each experiment, feces and urine were collected after each feeding and added to manure storage containers. At the end of each experiment, manure slurries were monitored for gas emissions and chemical properties. In Exp. 1, regression analysis was used to determine the effects of S in the diet. Sulfur lowered manure pH by 1.36 units, but increased S and sulfide levels in manure by 57% and 0.8%, respectively, for each g of S added to the diet. Sulfur increased emissions of H2S by 8% and odor by 2% for each g of S increase in the diet. In Exp. 2, ANOVA indicated that S source had a significant effect on excretion of DM, C, N, S in manure. Animals fed FM and DDGS diets had significantly higher levels of VFAs, phenols, and sulfide in manure compared to animals fed CSBM diets. The S levels in the diets significantly increased odor emissions compared to CSBM diets. Animals fed FM and DDGS had a greater percentage of chemical odor associated with VOCs than CSBM diets, and animals fed FM diets had significantly higher levels of odor emissions. In conclusion, dietary S levels and the source of S have a dramatic impact on manure composition and gas emissions. [ABSTRACT FROM AUTHOR]

An abstract of the article "Efficacy of Postwash Shell Egg Sanitizers," by M.T. Musgrove and colleagues is presented.

An abstract of the article "Effects of Postprocessing Shell Surface Sanitizers on Egg Physical Quality," by D.R. Jones is presented.

Two soils, Puyallup fine sandy loam from Puyallup, WA, and Ellzey fine sand from Hastings, FL, each with a prior history of carbofuran exposure but with different pedological and climatological characteristics, were found to exhibit enhanced degradation toward carbofuran in surface and subsurface soil layers. The treated Puyallup and Ellzey soils exhibited higher mineralization rates for both the carbonyl and the aromatic ring of carbofuran when compared to untreated soils. Disappearance rates of [14C-URL (uniformly ring labeled)] carbofuran in the treated Ellzey soil was faster than in untreated soil, and also faster in surface soil than in subsurface soil. Initial degradation patterns in the treated Ellzey soil were also different from those in the untreated soil. The treated Ellzey soil degraded carbofuran mainlythrough biological hydrolysis, while untreated soil degraded carbofuran through both oxidative and hydrolytic processes. [ABSTRACT FROM AUTHOR]

Outbreaks of infectious diseases involving depopulation of animals require on-farm practices to stage carcasses when final disposal methods are unavailable. The current study assessed various materials and techniques for containing carcasses to minimize leachate and biological substances. The tested materials included tarps, soil, corn stover (CS), and lime, while the methods involved covers, chemical additives, barriers, and containment. Treatments included the following: 1) control, carcasses in a pile; 2) carcasses wrapped in tarp material; 3) carcasses covered with tarp material; 4) carcasses covered by soil; 5) carcasses placed on CS base with tarp cover; 6) carcasses on CS base with CS covering; and 7) carcasses on CS base with a lime covering. Each treatment was run in triplicate using three carcasses per replicate. Temperatures, headspace gas, and leachate from carcasses were collected over a 91-day holding period. Pairwise comparisons of means were made when treatments were significantly different. Carcasses lost significant amounts of their liquid contents in the first 27 days. Leachate contents were initially filled with organic material and potassium that significantly declined with time, while Fe, Zn, and Cu concentrations increased significantly over time. Covers did not reduce leachate volume, but soil covers significantly reduced substances in the leachate. Corn stover barriers significantly reduced both leachate volume and substances in the leachate. Containing carcasses in tarp material was the most effective method for holding leachate and preventing its loss to the environment. This research demonstrates that growers should focus on sealing carcass containers and constructing barriers to limit surface contamination during depopulation events., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Pit recharge systems (PRS) control odor by managing organic solids in swine manure. However, there needs to be more understanding of PRS's effect on the microbiome composition and its impact on odor formation. A study was conducted to understand how recharge intervals used in PRS impact manure microbiome and odor formation. Bioreactors dynamically loaded simulated recharge intervals of 14, 10, and 4 days by diluting swine manure with lagoon effluent at varying ratios. Treatment ratios tested included 10:0 (control), 7:3 (typical Korean PRS), 5:5 (enhanced PRS #1), and 2:8 (enhanced PRS #2). Manure microbial membership, chemical concentrations, and odorant concentrations were used to identify the interactions between microbiota, manure, and odor. The initial microbial community structure was controlled by dilution ratio and manure barn source material. Firmicutes and Proteobacteria were the dominant microbial phyla in manure and lagoon effluent, respectively, and significantly decreased or increased with dilution. Key microbial species were Clostridium saudiense in manure and Pseudomonas caeni in lagoon effluent. Percentages of these species declined by 8.9% or increased by 17.6%, respectively, with each unit dilution. Microbial community composition was controlled by both treatment (i.e., manure dilution ratio and barn source material) and environmental factors (i.e., solids and pH). Microbiome composition was correlated with manure odor formation profiles, but this effect was inseparable from environmental factors, which explained over 75% of the variance in odor profiles. Consequently, monitoring solids and pH in recharge waters will significantly impact odor control in PRS., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

A study was conducted to determine the effectiveness of supplementing swine manure with Bacillus subtilis (BS) to improve digestion of manure solids and lower odor emission. Large bioreactors (400 L) with manure (100 L) were treated with commercially available BS at a rate of 1% manure volume by either directly pouring or surface spraying the manure with inoculum. Manure physicochemical properties, gas emissions, and microbiome were monitored. Manures treated multiple times with BS or surface sprayed had significantly (P < 0.05) lower electrical conductivity, volatile solids, and chemical oxygen demand, by 3-5% compared to non-treated control manures. Volatile sulfur compound emissions (VSCs) were reduced by 20-30% in both experiments, while ammonia and volatile organic compounds were reduced by 40% and 15%, respectively, in surface spray experiment only. The manure indigenous microbiome remained relatively stable following treatment and BS were never detected in the raw or treated manure following multiple treatments. The reduction in manure organic carbon and VSCs emissions were a result of physical mixing during manure treatment and biological material in the microbial inoculum stimulating microbial activity and not growth of BS., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Swine growers seeking to lower costs and environmental impact have turned to alternative carbohydrate feed sources. A feeding trial was conducted to determine the effect carbohydrate sources have on manure composition and gas emissions. A total of 48 gilts averaging 138 kg BW were fed diets consisting of (a) low fiber (LF) grain, or (b) high fiber (HF) aro-industrial co-product (AICP). The LF diets included corn and soybean meal (CSBM) and barley soybean meal (BSBM). The HF AICP diets were CSBM based and supplemented with one of the following materials: beet pulp; corn distillers dried grains with solubles; soybean hulls; or wheat bran. Diets were fed for 42 d with an average daily feed intake of 2.71 kg d -1 . Feces and urine were collected twice daily and added to manure storage containers in which manure slurries were monitored for gas emissions and chemical properties. Manures of animals fed HF diets had significantly (P < 0.05) more excretion of solids, C, N, and organic N, but less total S compared to pigs fed the LF diets. Animals feed HF diets had significantly (P < 0.05) higher levels of ammonia, sulfide, volatile fatty acids, and phenols in manure compared to pigs fed the LF diets. Manure of animals fed HF diets had 30% (P < 0.05) lower NH 3 and 17% lower hydrogen sulfide emissions; however, fiber had no impact on odor emissions. Based on the partitioning of nutrients, animals fed HF fiber diets had increased manure retention for C and N but decreased levels of N gas emissions and manure S. There were little differences in manure and gas emissions for animals fed LF diets, but the source of HF AICP diets had a significant impact on manure composition and gas emissions., Competing Interests: Declaration of competing interest The authors wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome., (Published by Elsevier B.V.)

Aim: Swine manure foaming is a major problem, causing damage to property, livestock, and people. Here, we identified the main chemicals and microbes that contribute to foaming., Methods and Results: Foaming and non-foaming swine manure were sampled from farms in Iowa and Illinois. Targeted and untargeted metabolomics analyses identified chemical markers that differed between foaming and non-foaming manure and between manure layers. Microbial community analysis and metagenomics were performed on a subset of samples. Foam contained significantly higher levels of total bile acids and long chain fatty acids like palmitic, stearic and oleic acid than the other manure layers. Foam layers also had significantly higher levels of ubiquinone 9 and ubiquinone 10. The slurry layer of foaming samples contained more alanine, isoleucine/leucine, diacylglycerols (DG), phosphtatidylethanolamines, and vitamin K2, while ceramide was significantly increased in the slurry layer of non-foaming samples. Eubacterium coprostanoligenes and Methanoculleus were more abundant in foaming samples, and E. coprostanoligenes was significantly correlated with levels of DG. Genes involved in diacylglycerol biosynthesis and in the biosynthesis of branched-chain hydrophobic amino acids were overrepresented in foaming samples., Conclusions: A mechanism for manure foaming is hypothesized in which proliferation of Methanoculleus leads to excessive production of methane, while production of DG by E. coprostanoligenes and hydrophobic proteins by Methanosphaera stadtmanae facilitates bubble formation and stabilization., Significance and Impact of Study: While some chemical and biological treatments have been developed to treat swine manure foaming, its causes remain unknown. We identified key microbes and metabolites that correlate with foaming and point to possible roles of other factors like animal feed., (© 2021 The Society for Applied Microbiology.)

Foam accumulation in swine manure deep-pits has been linked to explosions and flash fires that pose devastating threats to humans and livestock. It is clear that methane accumulation within these pits is the fuel for the fire; it is not understood what microbial drivers cause the accumulation and stabilization of methane. Here, we conducted a 13-month field study to survey the physical, chemical, and biological changes of pit-manure across 46 farms in Iowa. Our results showed that an increased methane production rate was associated with less digestible feed ingredients, suggesting that diet influences the storage pit's microbiome. Targeted sequencing of the bacterial 16S rRNA and archaeal mcrA genes was used to identify microbial communities' role and influence. We found that microbial communities in foaming and non-foaming manure were significantly different, and that the bacterial communities of foaming manure were more stable than those of non-foaming manure. Foaming manure methanogen communities were enriched with uncharacterized methanogens whose presence strongly correlated with high methane production rates. We also observed strong correlations between feed ration, manure characteristics, and the relative abundance of specific taxa, suggesting that manure foaming is linked to microbial community assemblage driven by efficient free long-chain fatty acid degradation by hydrogenotrophic methanogenesis., Competing Interests: The authors have declared that no competing interests exist.

Soybean meal is the dominate protein source for swine diets in the world driven largely by economics, nutritive value, and availability; but conditions can change requiring growers to consider more economical and available protein alternatives. A feeding trial was conducted to determine the impact dietary protein source material on manure slurry chemical properties and manure gas emissions. A total of 32 gilts averaging 130 kg BW were fed either a control diet formulated with soybean meal (SB) or an alternative protein source that included corn gluten meal (CG); canola meal (CM); or poultry meal (PM), with all diets containing 176 g protein kg -1 . Diets were fed for 45 d with an average daily feed intake of 2.68 kg/d. Feces and urine were collected twice daily after each feeding and added to animal-specific manure storage containers. At the end of the study, manure slurries were monitored for gas emissions and chemical properties. Dietary protein source had a significant effect (P < 0.05) on manure pH, total solids, total C, protein N, and total S. Pigs fed the diets containing CM had significantly higher levels of sulfide, butanoic acid, and branch chain fatty acids compared to pigs fed SB diets (P < 0.05). Pigs fed CM diets had significantly lower emissions of NH 3 compared to pigs fed SB diets (P < 0.05). There were no significant differences in C or S emissions or in odorant emission as affected by source of dietary protein. Hydrogen sulfide was the most dominate odorants for all dietary treatments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Manure management systems have a major impact on odor from swine operations. A study was conducted to compare deep-pit manure management systems to flushing barn manure management systems for odor reduction and organic matter degradation. Bioreactors were used to mimic manure management systems in which manure and lagoon effluent were loaded initially, and subsequent manure was added daily at 5% of its storage capacity (1 L). Final manure-to-lagoon effluent ratios were 10:0 (deep-pit manure management system), 7:3 (Korean flushing systems), 5:5 (enhanced flushing systems), and 2:8 (enhanced flushing systems). At the end of the trial, at 4 (2:8), 10 (5:5), or 14 (10:0, 7:3) d, manure and gas concentrations of odorants were measured, including total solids (TS), total N (TN), and total C (TC) of manure. Odor was evaluated using the odor activity values (OAVs), and regression analysis was used to determine the effects of dilution and TS on manure properties and OAVs. Solids in the manure were positively correlated to TN, TC, straight chain fatty acids (SCFAs), branch chain fatty acids (BCFAs), total phenols, and total indoles and positively correlated to OAV for SCFAs, BCFAs, ammonia, total phenols, and total indoles. Reducing TS by 90% reduced BCFA, ammonia, phenols, and indoles by equal amounts in air. Carbon dioxide was the main C source evolved, averaging over 90%, and CH 4 increased with dilution quadratically. Overall, reducing solids in manure by dilution had the biggest impact on reducing odor and increasing organic C degradation., (© 2021 The Authors. Journal of Environmental Quality © 2021 American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Crude protein (CP) is a key nutrient in swine diets supplying essential amino acids, N, and S to animals for growth are fed in excess to maximize growth. Swine diets reduced in CP and supplemented with crystalline amino acids have been shown effective at maintaining animal growth while increasing overall CP use efficiency. A feeding trial study was conducted to determine the effects of reduced dietary CP levels on manure slurry chemical properties and gas emissions. A total of 24 gilts averaging 111 kg BW were fed corn and soybean meal diets formulated with 8.7, 14.8, and 17.6% CP using crystalline amino acid supplementation in the 8.7 and 14.8% CP diets, but only intact protein, soybean meal, in the diet containing 17.6% CP. Diets were fed for 45 d with an average daily feed intake (ADFI) of 2.70 kg across all diets. Animals were fed twice daily with both feces and urine collected during each feeding and added to animal-specific manure storage containers. At the end of the study, manure slurries were monitored for gas emissions and chemical properties. Increasing dietary CP levels increased manure pH, total solids, total N, and total S, including increased levels of ammonia (NH 3 ), volatile fatty acids, and phenolic compounds. Pigs fed lower CP diets had lower emissions of NH 3 , branched chain fatty acids (BCFA), and phenol compounds which translated into lower emissions in total odor. Emissions of NH 3 and odor were reduced by 8.9% and 4.2%, respectively, for each unit percent decline in dietary CP. Hydrogen sulfide was the dominate odorant associated with manure odor emissions. Based on nutrient mass balance, animal retention of dietary N and S increased by 7.0% and 2.4%, respectively, for each unit percent drop in crude protein fed animals, while C retention in the animal declined by 2.1%., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Sulfur is a key nutrient in swine diets and is associated with hydrogen sulfide (H 2 S) emissions, odor, and respiratory distress of animals. Due to potential increases in S levels in swine diets by using alternative feedstuffs, a feeding trial study was conducted to determine the effect of dietary S source has on manure slurry chemical properties and gas emissions. A total of 24 gilts averaging 139 kg BW were fed a control diet formulated with corn and soybean meal (CSBM) containing 1.80 g S kg -1 or diets containing 3.50 g S kg -1 feed as supplied by calcium sulfate (CaSO 4 ), distillers dried grains with solubles (DDGS), or feather meal (CFM). Diets were fed for 41 d with an ADFI of 2.70 kg/d. Feces and urine were collected twice daily after each feeding and added to the manure storage containers. At the end of the study, manure slurries were monitored for gas emissions and chemical properties. Dietary S source had a significant effect on excretion of DM, C, N, and S in manure. Pigs fed the diets containing DDGS had significantly higher levels of NH 3 , VFAs, and phenols in manure compared to pigs fed the CSBM diet. Pigs fed diets with organic S (i.e., DDGS and CFM) had lower emissions of H 2 S compared to pigs fed the diet with inorganic sulfur (CaSO 4 ). In contrast, there were no significant differences in C or N emissions as affected by dietary treatment. Odor and odorant emissions differed by dietary treatment, with pigs fed the CFM diet having the highest odor emissions as compared to pigs fed the control CSBM diet. Pigs fed diets containing CFM and DDGS had a greater percentage of their chemical odor associated with volatile organic compounds while animals fed the CSBM diet or the diet with CaSO 4 had greater percentage associated with H 2 S emissions., (Published by Elsevier B.V.)

Sulfur is an essential nutrient for animal growth but is also associated with odor and morbidity of animals from swine operations. A study was conducted to determine the effects of increasing dietary S levels in swine diets on DM, pH, C, N, S, VFA, indole, and phenol concentrations in the manure, and on the emissions of C-, N-, and S-containing gases. A total of 24 gilts averaging 152 kg BW were fed diets containing 0.19, 0.30, 0.43, or 0.64% dietary S, as supplied by CaSO 4 , for 31 d, with an ADFI of 3.034 kg d -1 . Feces and urine were collected after each feeding and added to manure storage containers. At the end of the study, manure slurries were monitored for gas emissions and chemical properties. Increasing dietary S lowered manure pH by 0.3 units and increased DM, N, and S by 10% for each 1.0 g S increase kg -1 feed intake. Increased dietary S increased NH 3 , sulfide, butanoic, and pentanoic acid concentrations in manure. Carbon and N emissions were not significantly impacted by dietary S, but S emissions in the form of hydrogen sulfide (H 2 S) increased by 8% for each 1.0 g S increase kg -1 feed intake. Odor increased by 2% for each 1.0 g increase of S consumed kg -1 feed intake. Phenolic compounds and H 2 S were the major odorants emitted from manure that increased with increasing dietary S., (Published by Elsevier B.V.)

Odor emissions from swine finishing operations are an air quality issue that affects residents at the local level. A study was conducted at a commercial swine deep-pit finishing operation in central Iowa to monitor odorous compounds emitted and transported offsite. Gaseous compounds were sampled using either sorbent tubes or canisters with GC/MS analysis, and particulates matter (PM 10 ) were sampled with high volume samplers and thermally extracted onto sorbent tubes for GC/MS analysis. Major odorous chemical classes detected at the swine facility included volatile sulfur compounds (VSC), volatile fatty acids (VFA), phenol and indole compounds. Manure storage was the main source of odorous compounds of which hydrogen sulfide (H 2 S), methanethiol, 4-methylphenol, and 3-methylindole were key offenders. Only H 2 S and 4-methylphenol were detected above odor threshold values (OTV) at all locations around the facility and both 4-methylphenol and 3-methylindole were detected above their OTV 1.5 km downwind from the swine facility. Odorous compounds generated during agitation and pumping of the deep pits was mainly H 2 S. Odorants were mainly transported in the gas phase with less than 0.1% being associated with PM 10 . Odor mitigation efforts should focus on gaseous compounds emitted from deep-pits and especially during manure agitation and deep-pit pumping., (Published by Elsevier Ltd.)

This study was conducted to determine the impact of diets containing dried distillers grains with solubles (DDGS) on emissions of odor and odorous compounds from swine manure storage. Twenty-four pigs were fed either a corn-soybean meal (CSBM) diet or a diet containing 35% DDGS over a 42-d feeding trial. Their waste was collected and transferred to individual manure storage containers. Manure from pigs fed diets containing DDGS had significantly lower odorant emissions expressed in animal units for hydrogen sulfide (HS) and ammonia (NH) ( < 0.05) compared with pigs fed the CSBM diet, but emissions of volatile fatty acids and phenolic compounds were significantly higher ( < 0.05) for manures from animals fed the DDGS diet. There was no significant difference for indole compound emissions due to the dietary treatment applied. Emissions of volatile organic compounds (VOCs) from manure accounted for less than 0.1% of carbon consumed for either diet. There were no significant differences in odor emissions for either diet as quantified with human panels or measured as the sum total of the odor activity value. Manure odors from pigs fed the CSBM diet were dominated by HS, whereas animals fed the diet containing DDGS were dominated by VOCs., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Foam accumulation in deep-pit manure storage facilities is of concern for swine producers because of the logistical and safety-related problems it creates. A feeding trial was performed to evaluate the impact of feed grind size, fiber source, and manure inoculation on foaming characteristics. Animals were fed: (1) C-SBM (corn-soybean meal): (2) C-DDGS (corn-dried distiller grains with solubles); and (3) C-Soybean Hull (corn-soybean meal with soybean hulls) with each diet ground to either fine (374 μm) or coarse (631 μm) particle size. Two sets of 24 pigs were fed and their manure collected. Factors that decreased feed digestibility (larger grind size and increased fiber content) resulted in increased solids loading to the manure, greater foaming characteristics, more particles in the critical particle size range (2-25 μm), and a greater biological activity/potential., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Developing new strategies to rapidly incorporate the fac-[M(I)(CO)3](+) (M = Re, (99m)Tc) core into biological targeting vectors in radiopharmaceuticals continues to expand as molecules become more complex and as efforts to minimize nonspecific binding increase. This work examines a novel isothiocyanate-functionalized bifunctional chelate based on 2,2'-dipicolylamine (DPA) specifically designed for complexing the fac-[M(I)(CO)3](+) core. Two strategies (postlabeling and prelabeling) were explored using the isothiocyanate-functionalized DPA to determine the effectiveness of assembly on the overall yield and purity of the complex with amine containing biomolecules. A model amino acid (lysine) examined (1) amine conjugation of isothiocyanate-functionalized DPA followed by complexation with fac-[M(I)(CO)3](+) (postlabeling) and (2) complexation of fac-[M(I)(CO)3](+) with isothiocyanate-functionalized DPA followed by amine conjugation (prelabeling). Conducted with stable Re and radioactive (99m)Tc analogs, both strategies formed the product in good to excellent yields under macroscopic and radiotracer concentrations. A synthetic peptide (AE105) which targets an emerging biomarker in CaP prognosis, urokinase-type plasminogen activator receptor (uPAR), was also explored using the isothiocyanate-functionalized DPA strategy. In vitro PC-3 (uPAR+) cell uptake assays with the (99m)Tc-labeled peptide (8a) showed 4.2 ± 0.5% uptake at 4 h. In a murine model bearing PC-3 tumor xenografts, in vivo biodistribution of 8a led to favorable tumor uptake (3.7 ± 0.7% ID/g) at 4 h p.i. with relatively low accumulation (<2% ID/g) in normal organs not associated with normal peptide excretion. These results illustrate the promise of the isothiocyanate-functionalized approach for labeling amine containing biological targeting vectors with fac-[M(I)(CO)3](+)., Competing Interests: Notes The authors declare no competing financial interest.

Alum [Al(SO4) ·14HO] addition to poultry litter has been shown to reduce ammonia (NH) concentrations in poultry houses; however, its effects on greenhouse gas (GHG; NO, CH, and CO) emissions is unknown. The objectives of this study were to determine the effects of alum additions on (i) in-house NH and GHG concentrations, (ii) NH and GHG emissions, and (iii) litter chemical properties. Two identical broiler houses located in northwest Arkansas were used for this study: one house was a control and the other was treated with alum between each flock of birds. Ventilation rates were coupled with in-house NH and GHG measurements to determine emission rates. Overall, alum additions significantly reduced the daily average in-house NH concentration by 42% (8.9 vs. 15.4 μL L), and the overall NH emission rate was reduced by 47% (7.2 vs. 13.4 kg d house). The average cumulative NH emission for the three flocks was 330 kg house flock for the alum-treated house and 617 kg house flock for the control. Concentrations and emissions of nitrous oxide (NO) and methane (CH) from the alum-treated house were not significantly different than the untreated house. However, carbon dioxide (CO) emissions were significantly higher from the untreated house than the alum-treated house. Alum also significantly increased litter N content and reduced the C/N ratio. These results indicate that the addition of alum to poultry litter is not only an effective management practice for reducing in-house NH concentrations and emissions but also significantly reduces CO emissions from poultry facilities., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Methane emission is an important tool in the evaluation of manure management systems due to the potential impact it has on global climate change. Field procedures used for estimating methane emission rates require expensive equipment, are time consuming, and highly variable between farms. The purpose of this paper is to report a simple laboratory procedure for estimating methane emission from stored manure. The test developed was termed a methane production rate (MPR) assay as it provides a short-term biogas production measurement. The MPR assay incubation time is short (3d), requires no sample preparation in terms of inoculation or dilution of manure, is incubated at room temperature, and the manure is kept stationary. These conditions allow for high throughput of samples and were chosen to replicate the conditions within deep-pit manure storages. In brief, an unaltered aliquot of manure was incubated at room temperature for a three-days to assay the current rate of methane being generated by the manure. The results from this assay predict an average methane emission factor of 12.2 ± 8.1 kg CH4 head(-1) yr(-1) per year, or about 5.5 ± 3.7 kg CH4 per finished animal, both of which compare well to literature values of 5.5 ± 1.1 kg CH4 per finished pig for deep-pit systems (Liu et al., 2013). The average methane flux across all sites and months was estimated to be 22 ± 17 mg CH4 m(-2)-min(-1), which is within literature values for deep-pit systems ranging from 0.24 to 63 mg CH4 m(-2)-min(-1) (Park et al., 2006) and similar to the 15 mg CH4 m(-2)-min(-1) estimated by (Zahn et al., 2001)., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

While a number of chelate strategies have been developed for the organometallic precursor fac-[M(I)(OH2)3(CO)3](+) (M = Re, (99m)Tc), a unique challenge has been to improve the overall function and performance of these complexes for in vivo and in vitro applications. Since its discovery, fac-[M(I)(OH2)3(CO)3](+) has served as an essential scaffold for the development of new targeted (99m)Tc based radiopharmaceuticals due to its labile aquo ligands. However, the lipophilic nature of the fac-[M(I)(CO)3](+) core can influence the in vivo pharmacokinetics and biodistribution of the complexes. In an effort to understand and improve this behavior, monosubstituted pyridine ligands were used to assess the impact of donor nitrogen basicity on binding strength and stability of fac-[M(I)(CO)3](+) in a 2 + 1 labeling strategy. A series of Re and (99m)Tc complexes were synthesized with picolinic acid as a bidentate ligand and 4-substituted pyridine ligands. These complexes were designed to probe the effect of pKa from the monodentate pyridine ligand both at the macro scale and radiochemical concentrations. Comparison of X-ray structural data and radiochemical solution experiments clearly indicate an increase in overall yield and stability as pyridine basicity increased.

Swine producers are supplementing animal diets with increased levels of dried distillers grains with solubles (DDGS) to offset the cost of a standard corn-soybean meal (CSBM) diet. However, the environmental impact of these diets on emissions of greenhouse gases, ammonia (NH), and hydrogen sulfide (HS) is largely unknown. Twenty-four pigs (103.6 kg initial body weight) were fed a standard CSBM diet or a CSBM diet containing 35% DDGS for 42 d. Pigs were fed and their manure was collected twice daily over the 42-d trial. Pigs fed diets containing DDGS had reduced manure pH ( < 0.01), increased surface crust coverage ( < 0.01), increased manure dry matter content ( < 0.01), and increased manure C ( < 0.01), N ( < 0.01), and S ( < 0.01) contents. Animals fed DDGS diets also had significantly higher concentrations of total ammoniacal nitrogen ( < 0.01) and sulfide ( < 0.01) in their manure compared with animals fed CSBM diets. Manure emissions of NH ( < 0.01) and HS ( < 0.05) were significantly higher in animals fed the CSBM diet. There was no dietary treatment effect for methane or nitrous oxide emissions from manure. This study demonstrates that diets containing DDGS can significantly affect manure composition and potentially lower emissions of NH and HS., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Quantifying non-methane hydrocarbons (NMHC) from animal feeding operations (AFOs) is challenging due to the broad spectrum of compounds and the polar nature of the most abundant compounds. The purpose of this study was to determine the performance of commercial NMHC analyzers for measuring volatile organic compounds (VOCs) commonly emitted from AFOs. Three different NMHC analyzers were tested for response to laboratory generated VOCs, and two were tested in the field at a commercial poultry facility. The NMHC analyzers tested included gas chromatography/flame ionization detector (GC/FID), photoacoustic infrared (PA-IR) and photoionization detector (PID). The GC/FID NHHC analyzer was linear in response to nonpolar compounds, but detector response to polar oxygenated compounds were lower than expected due to poor peak shape on the column. The PA-IR NMHC instrument responded well to the calibration standard (propane), methanol, and acetone, but it performed poorly with larger alcohols and ketones and acetonitrile. The PA-IR response varied between compounds in similar compound classes. The PID responded poorly to many of the most abundant VOCs at AFOs, and it underreported alcohols by > 70%. In the field monitoring study, total NMHC concentrations were calculated from sum total of VOC determined using EPA Methods TO-15 and TO-17 with GC-MS compared to results from NMHC analyzers. NMHC GC/FID values were greater than the values calculated from the individual compound measurements. This indicated the presence of small hydrocarbons not measured with TO-15 or TO-17 such as propane. The PA-IR response was variable, but it was always lower than the GC/FID response. Results suggest that improved approaches are needed to accurately determine the VOC profile and NMHC emission rates from AFOs.

The National Research Council identified odors as a significant animal emission and highlighted the need to develop standardized protocols for sampling and analysis. The purpose of our study was to compare different odor sampling techniques for monitoring odors emitted from stored swine manure. In our study, odorous headspace air from swine manure holding tanks were analyzed by human panels and analytical techniques. Odorous air was analyzed by human panels using dynamic dilution olfactometry (DDO). Chemical analysis used acid traps for ammonia (NH₃), fluorescence for hydrogen sulfide (H₂S), and thermal desorption gas chromatography-mass spectrometry for volatile organic compounds (VOCs). Chemical analysis included the use of gas chromatography-olfactometry (GC-O) for determining key odorants. Chemical odorant concentrations were converted to odor activity values (OAVs) based on literature odor thresholds. The GC-O technique used was GC-SNIF. Dilution thresholds measured by different odor panels were significantly different by almost an order of magnitude even though the main odorous compound concentrations had not changed significantly. Only 5% of the key odorous VOCs total OAVs was recovered from the Tedlar bags used in DDO analysis. Ammonia was the only chemical odorant significantly correlated with DDO analysis in the fresh (1 wk) and aged manure. Chemical analysis showed that odor concentration stabilized after 5 to 7 wk and that HS was the most dominant odorant. In aged manure, neither volatile fatty acids (VFAs) nor HS was correlated with any other chemical odorant, but NH, phenols, and indoles were correlated, and phenols and indoles were highly correlated. Correlation of odorant concentration was closely associated with the origin of the odorant in the diet. Key odorants determined by chemical and GC-O included indoles, phenols, NH₃, and several VFAs (butanoic, 3-methylbutanoic, and pentanoic acids)., (by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Bovine rumen fluid was fermented anaerobically with 25 mM R-propylene glycol, S-propylene glycol, or glycerol added. After 24 h, all of the propylene glycol enantiomers and approximately 80% of the glycerol were metabolized. Acetate, propionate, butyrate, valerate, and caproate concentrations, in decreasing order, all increased with incubation time. Addition of any of the three substrates somewhat decreased acetate formation, while addition of either propylene glycol increased propionate formation but decreased that of butyrate. R- and S-propylene glycol did not differ significantly in either their rates of disappearance or the products formed when they were added to the fermentation medium. Fermentations of rumen fluid containing propylene glycol emitted the sulfur-containing gases 1-propanethiol, 1-(methylthio)propane, methylthiirane, 2,4-dimethylthiophene, 1-(methylthio)-1-propanethiol, dipropyl disulfide, 1-(propylthio)-1-propanethiol, dipropyl trisulfide, 3,5-diethyl-1,2,4-trithiolane, 2-ethyl-1,3-dithiane, and 2,4,6-triethyl-1,3,5-trithiane. Metabolic pathways that yield each of these gases are proposed. The sulfur-containing gases produced during propylene glycol fermentation in the rumen may contribute to the toxic effects seen in cattle when high doses are administered for therapeutic purposes.

The kinetics and mechanism(s) of the hydrolytic degradation of a compound are needed to evaluate a compound's abiotic degradation in the environment. In this paper, the hydrolysis of cymoxanil [2-cyano-N-[(ethylamino)carbonyl]-2-(methoxyimino) acetamide] was investigated in dark sterile aqueous solutions under a variety of pH conditions (pH 2.8-9.2) and temperatures (15-50 degrees C). Hydrolysis of cymoxanil was described by first-order kinetics, which was dependent on pH and temperature. Cymoxanil degraded rapidly at pH 9 (half-life = 31 min) and relatively slowly at pH 2.8 (half-life = 722 days). The effect of temperature on the rate of cymoxanil degradation was characterized using the Arrhenius equation with an estimated energy of activation of 117.1 kJ mol(-)(1). An increase in temperature of 10 degrees C resulted in a decrease in half-life by a factor of approximately 5. Three competing degradation pathways are proposed for the hydrolysis of cymoxanil, with two of the pathways accounting for approximately 90% of cymoxanil degradation. These two pathways involved either initial cyclization to 1-ethyldihydro-6-imino-2,3,5(3H)-pyrimidinetrione-5-(O-methyloxime) (1, Figure 1) or direct cleavage of the C-1 amide bond to form cyano(methoxyimino) acetic acid (7). The third pathway of degradation involved initial cyclization to 3-ethyl-4-(methoxyimino)-2,5-dioxo-4-imidazolidinecarbonitrile (8), which rapidly degrades into 1-ethyl-5-(methoxyimino)-2,4-imidazoline-2,4-dione (9). All three pathways eventually lead to the formation of the polar metabolite oxalic acid.