Urine Application Research Articles

Evaluation of the effect of urine dip vs urine drip on multi-test strip results.

Standard operating procedures, including World Health Organization guidelines for packed cell volume, are established for in-clinic laboratory tests. No independent, evidence-based guidelines exist for dipstick urinalysis; however, manufacturer's instructions state to dip the stick into urine. In veterinary medicine, small volume urine samples could preclude dipping; therefore, a single drip per pad from a pipette or syringe is often performed. This study aimed to examine the differences between these two urine application methods prior to analysis, with the hypothesis that the method type would not effect on test results of dipstick analysis. To standardize the strip analysis method, a Siemens Clinitek Status+analyzer was used with Multistix10SG dipsticks. Three investigators tested urines from 53 dogs with a range of diseases by both methods. Results were assessed for the degree of agreement between the methods and within method variability. Overall, the agreement between methods was high. Within each method, the drip method variability was higher than that of the dip method (P=0.012). Disagreements between methods were present, with pH and blood having the lowest agreement levels. Glucose was more likely to be positive on the drip compared with the dip methodology. This study demonstrates potential clinically relevant differences between the two methods and a higher level of variability with the drip methodology. Therefore, while the drip method could be used for practical reasons (eg, low sample volumes), this study supports the manufacturer's recommended method of dipping the dip stick into urine rather than dripping urine onto each pad with a pipette or syringe.

Evaluating the effects of canine urine on urban soil microbial communities

Due to extensive areas of impermeable surfaces, combined sewer overflow (CSO) is currently a major problem in urban areas across the United States. In CSO systems, sewage can travel through underground pipes to be decontaminated in treatment facilities, or it can combine with stormwater after a precipitation event and discharge into local waterways. Many cities are implementing green infrastructure installations, which use vegetation and bioactive soil microbial communities to enhance soil water-holding capacity, thereby minimizing CSO events. Understanding the factors that structure soil microbial communities in green infrastructure will facilitate more effective management of these engineered ecosystems; however, few studies to date have evaluated ecological patterns and processes of microbes in the urban environment. Nitrogen loading is known to be a major factor structuring fungi and bacteria in non-urban soils, and since cities also contain large populations of canines, N-rich urine deposition is a potential factor that could be important for structuring soil microbes in ground-level green infrastructure installations. Our study investigated the effects of canine urine on the urban soil microbial communities in a greenhouse experiment by treating Liriope muscari, a common plant found in New York City green infrastructure, with different concentrations of canine urine for 4 weeks in an experimental setting. We found that urine application significantly decreased total soil microbial biomass and microbial richness, and increased water runoff volume. These findings indicate that canine urine may have negative consequences for soil water-holding capacity and nutrient cycling in urban green infrastructure installations by directly decreasing the abundance and richness of soil microbial communities.

Application of ion chromatography with pulsed amperometric detection for the determination of trace cyanide in biological samples, including breast milk

Cyanide (CN) is the biomarker of exposure to the components of tobacco smoke, although its presence in biological samples is also due to the consumption of products containing cyanogenic glycosides. In this work, we determine the concentration of the free cyanide in urine, saliva and breast milk matrices, using ion chromatography with pulsed amperometric detection (IC-PAD). IC-PAD is an emerging method, with only few documented applications in urine and saliva, and the presented determination in breast milk is its first published report for any method. The biological samples, which were obtained from women staying in a maternity ward, showed cyanide concentrations spanning 1.82–98.47 μg L−1. Under the optimized chromatographic conditions, the IC-PAD system exhibited satisfactory repeatability (R < 3%, n = 3) and good linearity in the range of 1–100 μg L−1. Thus, it proved to be an effective tool for monitoring trace cyanide concentration in a series of human body fluid matrices, including breast milk. This last matrix is especially important due to the possible effect on infant health related to the mothers' smoking habits.

Urine effects on grass and legume nitrogen isotopic composition: Pronounced short-term dynamics of δ15N.

Nitrogen stable isotope (15N) natural abundance is widely used to study nitrogen cycling. In grazed ecosystems, urine patches are hot-spots of nitrogen inputs, losses, and changes in δ15N. Understanding δ15N dynamics in urine-affected vegetation is therefore crucial for accurate inferences from 15N natural abundance in grasslands. We hypothesized that leaf δ15N following urine deposition varies with time and plant functional group. Specifically, we expected (i) short-term decreases in δ15N due to foliar absorption of 15N-depleted volatilized ammonia, (ii) followed by increases in δ15N due to uptake of 15N-enriched soil inorganic nitrogen, and (iii) that the magnitude of these changes is less in legumes than in grasses. The latter should be expected because ammonia absorption depends on leaf nitrogen concentration, which is higher in legumes than grasses, and because biological nitrogen fixation will modify the influence of urine-derived nitrogen on δ15N in legumes. We applied cattle urine to a mixture of Lolium perenne and Trifolium repens in a pot experiment. Nitrogen concentration and δ15N were determined for successive leaf cohorts and bulk biomass either 17 (early) or 32 (late) days after urine application. Early after urine application, leaves of L. perenne were 15N-depleted compared to control plants (δ15N 0.1 vs. 5.8‰, respectively), but leaves of T. repens were not (-1.1 vs. -1.1‰, respectively). Later, both species increased their δ15N, but T. repens (4.5‰) less so than L. perenne (5.9‰). Vegetation sampled within and outside urine patches in the field further supported these results. Our findings confirm that foliar ammonia uptake can substantially decrease grass foliar δ15N, and that in both grass and legume the direction of the δ15N response to urine changes over time. Temporal dynamics of plant δ15N at urine patches therefore need to be explicitly addressed when 15N natural abundance is used to study nitrogen cycling in grazed grasslands.

Effect of treated farm dairy effluents, with or without animal urine, on nitrous oxide emissions, ammonia oxidisers and denitrifiers in the soil

In New Zealand, the application of farm dairy effluent (FDE) on pasture soils is the third largest source of nitrous oxide (N2O) emissions from grazed grassland. Recently, new FDE treatment technologies have been developed to produce clarified water (CW) and treated effluent (TE) to recycle water and reduce the volume of fresh water used at the farm dairy. The aim of this study was to compare the effects of CW and TE with those of FDE on N2O emissions and the growth of ammonia-oxidising bacteria (AOB), ammonia-oxidising archaea (AOA) and denitrifiers, when the effluents were applied to a grazed pasture soil. A microcosm incubation study was carried out to determine the effects of applying CW, TE and untreated FDE, with or without animal urine, on N2O emissions, and the abundance of AOB, AOA and the denitrifying functional genes, including nirS, nirK and nosZ. The soil used was a Templeton silt loam (Udic Haplustepsts). The effluents were applied at nitrogen (N) rates equivalent to 100 kg N ha−1 and the animal urine at 700 kg N ha−1. The soils were incubated at 12 °C to simulate autumn/winter soil temperatures in New Zealand, and the soil moisture was maintained at field capacity. Results showed that the application of all the different effluents significantly increased the total N2O emissions (0.21–0.28 kg N2O-N ha−1) compared with that in the control (0.18 kg N2O-N ha−1). However, there were no significant differences in total N2O emissions between the different effluent treatments. Similarly, although the application of animal urine together with the different effluents further increased N2O emissions (7.7–8.8 kg N2O-N ha−1) above that from the urine only treatment (5.8 kg N2O-N ha−1), there were no significant differences among the different effluent plus urine treatments. These N2O results corresponded with the changing trends of the abundance of AOB, AOA, nirS, nirK and nosZ, that is the application of the CW, TE and FDE, with or without animal urine, had a similar impact on the growth dynamics of these microbial populations. These results indicate that the application of the CW and TE to dairy pasture soils would have a similar effect on N2O emissions, ammonia oxidisers and denitrifiers as that of the untreated FDE, with or without animal urine. The treated effluent or clear water from the new effluent treatment technology would therefore not increase N2O emissions nor adversely affect the key microbial populations involved in N cycling in soil.

Nutritional Quality of Tomato (&amp;lt;i&amp;gt;Lycopersicon lycopersicum&amp;lt;/i&amp;gt; L.) Varieties as Influenced by Combined Application of Human Urine and Rock Phosphate

There has been increasing interest in the quality of food produced in the sub-Saharan Africa and organic fertilizers can be used as palliative for eradicating malnutrition and improving the livelihood of the populace. A study was conducted in two phases, 4 × 5 × 2 and 2 × 4 factorial experiments in a completely randomized design with three replicates at the Department of Agronomy screenhouse, University of Ibadan, Nigeria. In the first experiment, five N levels (0, 20, 40, 60 and 80 kgN/ha) were combined with two P levels (0 and 20 kgP/ha) using urea and single superphosphate, respectively and four varieties (Roma VF, UC82B, Rio grande and Roma savana) of tomatoes were used. In the second experiment, optimum rates (60 kgN and 20 kgP/ha) from the first experiment formed the basis for the application of urea + SSP, urine + ORP, urea + SSP + urine + ORP and control. The best-performing varieties (Rio grande and Roma savana) in the first experiment were used. Data were subjected to analysis of variance. Combined application of N and P had higher N use efficiency and nutrient uptake than sole application of N or P. Urine + ORP based fertilizer mixtures were best for nutrient uptake and crop utilization of N and P. Increasing N levels led to decrease in nutrient use efficiency. Application of urine + ORP and urea + SSP gave better fruit qualities. The descending order of varietal superiority with respect to nutrient uptake, utilization and quality was: Rio grande > Roma savana > Roma VF > UC82B. Thus, urine + ORP based fertilizer mixtures have great potentials as substitutes for urea + SSP in the production of tomatoes.

Comparing the effectiveness and longevity of the urease inhibitor N-(2-nitrophenyl) phosphoric triamide (2-NPT) with N-(n-butyl) thiophosphoric triamide (nBTPT) in reducing ammonia emissions from cattle urine applied to dairy-grazed pasture soils

The objective of this laboratory incubation study was to assess the effectiveness and longevity of urease inhibitor N-(2-nitrophenyl) phosphoric triamide (2-NPT), along with the commonly used N-(n-butyl) thiophosphoric triamide (nBTPT), in reducing ammonia (NH3) emissions from cattle urine applied to pasture soils. It was hypothesised that 2-NPT would be effective as a longer-lasting inhibitor to reduce emissions after the deposition of urine during multiple grazing events. Two dairy-grazed pasture soils (Fluvisol, Rangitikei loamy sand (RLS) and Andosol, Egmont black loam (EBL)) with contrasting organic carbon levels and urease activity were used. The following treatments were applied to the soils at the start of the experiment: no inhibitor, nBTPT-low, 2-NPT-low, 2-NPT-medium and 2-NPT-high. Urine-N was applied to all the treatments at four stages: immediately before inhibitor application (Stage A), 29 days after inhibitor application (Stage B), 56 days after inhibitor application (Stage C) and 29 days and again 60 days after inhibitor application (Stage D); NH3 emissions were measured up to Day 31 after each urine application. The low, medium and high application rates of inhibitors were determined based on achieving 0.025%, 0.050% and 0.075% of quantity of urine-N applied in Stage A respectively. For the no inhibitor treatment, the proportion of total applied N in urine that was emitted as NH3 for the different stages ranged from 35.8% to 50.5% for RLS soil and from 14.2% to 26.7% for EBL soil. For Stage A, both inhibitors equally reduced NH3 emissions from applied urine in both soils (23.7–27.3% for the RLS and 20.6–27.2% for the EBL). For Stage B, significant reductions (4.2–13.4%) in NH3 emitted was observed only from RLS soil, with there being a significantly greater reduction from 2-NPT than from nBTPT, and 2-NPT continued to reduce NH3 emissions at Stage C (5.6–7.4%). There was no reduction in emissions during Stage D by either of the inhibitors. The results of this study suggest that 2-NPT can extend the longevity of urease inhibition and reduce NH3 emissions compared with the more commonly used inhibitor nBTPT in dairy-grazed pasture soils.

Analytical methodology for the simultaneous determination of NMG-Sb(v), iSb(v), and iSb(iii) species by anion exchange liquid chromatography in Glucantime® and its biological application in Wistar rat urine

An analytical method for the determination of Sb species in Glucantime® and rat urine samples.

Rapid increases in soil pH solubilise organic matter, dramatically increase denitrification potential and strongly stimulate microorganisms from the Firmicutes phylum.

Rapid and transient changes in pH frequently occur in soil, impacting dissolved organic matter (DOM) and other chemical attributes such as redox and oxygen conditions. Although we have detailed knowledge on microbial adaptation to long-term pH changes, little is known about the response of soil microbial communities to rapid pH change, nor how excess DOM might affect key aspects of microbial N processing. We used potassium hydroxide (KOH) to induce a range of soil pH changes likely to be observed after livestock urine or urea fertilizer application to soil. We also focus on nitrate reductive processes by incubating microcosms under anaerobic conditions for up to 48 h. Soil pH was elevated from 4.7 to 6.7, 8.3 or 8.8, and up to 240-fold higher DOM was mobilized by KOH compared to the controls. This increased microbial metabolism but there was no correlation between DOM concentrations and CO2 respiration nor N-metabolism rates. Microbial communities became dominated by Firmicutes bacteria within 16 h, while few changes were observed in the fungal communities. Changes in N-biogeochemistry were rapid and denitrification enzyme activity (DEA) increased up to 25-fold with the highest rates occurring in microcosms at pH 8.3 that had been incubated for 24-hour prior to measuring DEA. Nitrous oxide reductase was inactive in the pH 4.7 controls but at pH 8.3 the reduction rates exceeded 3,000 ng N2–N g−1 h−1 in the presence of native DOM. Evidence for dissimilatory nitrate reduction to ammonium and/or organic matter mineralisation was observed with ammonium increasing to concentrations up to 10 times the original native soil concentrations while significant concentrations of nitrate were utilised. Pure isolates from the microcosms were dominated by Bacillus spp. and exhibited varying nitrate reductive potential.

The application of urine derived stem cells in regeneration of musculoskeletal system

To review the application of urine derived stem cells (USCs) in regeneration of musculoskeletal system. The original literature about USCs in the regeneration of musculoskeletal system was extensively reviewed and analyzed. The source of USCs is noninvasive and extensive. USCs express MSCs surface markers with stable proliferative and multi-directional differentiation capabilities, and are widely used in bone, skin, nerve, and other skeletal and muscle system regeneration fields and show a certain repair capacity. USCs from non-invasive sources have a wide application prospect in the regeneration of musculoskeletal system, but the definite biological mechanism of its repair needs further study.

Ni‐based Catalysts for Hydrogen Production from Ammonia Decomposition: Effect of Dopants and Urine Application

AbstractAn enhancement of catalytic activities for ammonia decomposition was achieved using partial doping of Sr, Y, Zr, or Ce in Al2O3 frameworks. Improvements of the catalytic properties, including Ni dispersion, acidic sites, and basic sites have been studied. In this study, the Ni/doped Al2O3 catalysts exhibit a great improvement of Ni dispersion, which results in higher catalytic activities, relative to Ni/undoped Al2O3. Among the studied catalysts, Ni/Ce‐doped Al2O3 exhibits the highest NH3 conversion, and Ni/Y‐doped Al2O3 exhibits the best catalytic stability. The results of N2 formation from NH3‐TPRx imply that the recombination of nitrogen in the NH3 decomposition mechanism could be the rate‐determining step in this study. Decomposition of NH3 from urine was further evaluated over active Ni/Ce‐doped Al2O3. The catalyst can produce H2 in the range of 169‐188 μmol⋅min‐1⋅gcat‐1 with 72.1% NH3 conversion. The role of dopants in the Al2O3 frameworks for the catalytic activities was also discussed, to understand the NH3 decomposition mechanism.

Quantification of nitrous oxide emissions and emission factors from beef and dairy cattle excreta deposited on grazed pastoral hill lands

Excreta deposition by grazing livestock is the single largest source of agricultural nitrous oxide (N2O) emissions in New Zealand (NZ). N2O emissions and emission factors (EF3; percentage of excreta nitrogen emitted as N2O) from sheep, beef- and dairy-cattle excreta deposited can vary with differences in the hill land slope and disaggregation of EF3 based on slope may therefore result in a more accurate and improved inventory of national N2O emission. However, research data on N2O emissions from dairy cattle grazing on low and medium slopes of hill country or for beef cattle on low slopes is scarce. Field trials were therefore conducted in four regions of NZ on dairy-grazed (three regions) or sheep & beef cattle-grazed hill land (one region). N2O emissions were measured following dairy and beef cattle urine and dung application on low (<12°) and medium (12–24°) sloping land in late autumn/early winter. Application of either cattle urine or dung increased N2O emissions which mostly varied with excreta type (urine vs dung), slope class (low vs medium) or region. However, there was no significant (P > 0.05) slope-effect for EF3 values for beef and dairy cattle excreta (urine or dung) from each individual region, or combined from the three dairy-grazed sites. These findings confirm our hypothesis that N2O EF3 values for excretal inputs on established dairy hill land on low and medium slopes are similar for dairy-grazed hill land. However, the sheep & beef cattle grazed sites had lower (P < 0.05) EF3 for excreta deposited on medium slope land than for excreted deposited on low slope land. Our results help the refinement of NZ’s country-specific variations in EF3 to improve the accuracy and transparency of farm-, regional- and national-scale N2O inventories.

Soil nitrous oxide emissions from grassland: Potential inhibitor effect of hippuric acid

AbstractIn grassland systems, cattle and sheep urine patches are recognized as nitrous oxide (N2O) emission hot spots due to the high urinary nitrogen (N) concentrations. Hippuric acid (HA) is one of the constituents of ruminant urine that has been reported as a natural inhibitor of soil N2O emissions. The aim of this study was to examine the potential for elevated ruminant urine HA concentrations to reduce N2O emissions, in situ, on an acidic heavy clay soil under poorly drained conditions (WFPS &gt; 85%). A randomized complete block design experiment with three replications and four treatments was conducted using the closed‐static‐flux chamber methodology. The four treatments were applied inside the chambers: control with no artificial urine application (C), control artificial urine (U), and enriched artificial urine with two rates of HA (55.8 and 90 mM, U+HA1, U+HA2). Soil inorganic‐N, soil dissolved organic carbon (DOC), soil pH as well as N2O and methane (CH4) fluxes were monitored over a 79‐d period. Although N2O emissions were not affected by the HA enriched urine treatments, U+HA2 positively affected the retention of N as until day 3, when the soil pH dropped to values &lt; 5. Subsequently, as a consequence of rainfall events and soil acidification, it is likely that leaching or sorption onto clay reduced the efficacy of HA, masking any treatment differential effect on N2O emissions. Moreover, CH4 fluxes as well as DOC results reflected the soil anaerobic conditions which did not favour nitrification processes. Further research is needed to determine the fate of HA into the soil which might clarify the lack of an in situ effect of this compound.

Reducing nitrogen leaching losses in grazed dairy systems using an Italian ryegrass‐plantain‐white clover forage mix

AbstractIn grazed agricultural systems, animal urine patches are the major source of nitrogen (N) leaching losses and can cause a decline in water quality. Urine‐N rates often exceed plant requirements, and there is a need for mitigation options to reduce the impact of agriculture on the environment. One approach is to use alternative forages to reduce urine‐N loading rates, or to increase N uptake. This study used lysimeters to determine the N leaching losses, dry matter yields and N uptake following ruminant urine application to an Italian ryegrass‐plantain‐white clover forage mix (IRPWC,Lolium multiflorumLam.‐Plantago lanceolataL.‐Trifolium repensL.) or perennial ryegrass‐white clover (PRWC,Lolium perenneL.‐T. repensL.). Three urine treatments were applied: Control (no urine), Urine Actual (urine from cows grazing each of the forages: 508, and 664 kg N/ha, forIRPWCandPRWC, respectively) and Urine 700 (700 kg N/ha). Compared withPRWC(113 kg N/ha), N leaching losses were 88.9% lower fromIRPWC‐Urine Actual (12.5 kg N/ha) and 45.5% lower fromIRPWC‐Urine 700 (61.8 kg N/ha). These reductions were attributed partly to theIRPWChaving higher cool season activity and ability to take up N during the cool period, and partly to the lower concentration of urine‐N, compared withPRWC.IRPWCis a promising alternative forage for future farm systems with the ability to reduce urine‐N excretion from grazing animals and cause large reductions in N leaching losses while producing the same herbage dry matter yields asPRWC.

Participatory implementation of improving productivity and fruit quality of durian (Durio zibethinus) by enhanced fertilization in Southern Philippines

Farmer’s innovation of improving productivity of durian (Durio zibethinus Murr) trees by spraying goat urine was enhanced with combined application of fertilizers supplying boron and calcium. An experiment evaluating the efficacy of fermented goat urine combined with fertilizers supplying boron (20.5%) and calcium (34%) to improve productivity and postharvest quality of durian was conducted for two fruiting seasons. An 8-year-old durian trees in a farmer’s field at Bukidnon Province in Mindanao, Philippines were allowed to bear fruits for two seasons from March 2009 to June 2010. Foliar application of boron (20.5%) and fermented goat urine in combination with calcium (34%) significantly increased the number of fruits harvested per tree thus obtained the highest total yield and return of investment (ROI) per hectare during the two fruiting periods. Moreover, a significantly noticeable increased in percent edible portion was observed in fruits harvested from trees treated with boron (20.5%) applied singly or together with calcium (34%) and this was significantly enhanced with fermented goat urine application. Fruits from boron (20.5%) and fermented goat urine treatments have significantly high total soluble solids (TSS) with internal quality of fruits such as sweetness, aril flavor and overall quality increased compared to other treatments as evaluated by a taste panel.

Avaliação fenoprodutiva e teores clorofilianos de rabanete sob fertilização com urina de vaca e cobertura morta

The radish (Raphanus sativus L.) is a short-cycle vegetable that has a rapid demand for nutrients to grow and produce. Because of the small number of reports on organic fertilization with this crop, this work was conducted in the Plant Production Sector of the Course of Agroecology of the Picuí Campus ,IFPB and aimed to evaluate the attributes of growth, yield and chlorophyll index of radish in response to the application of cow urine, via soil, as an alternative fertilization. The experimental design was organized in randomized blocks, with four replications, in a 6 x 2 factorial arrangement, which corresponded to six concentrations of cow urine (0.00%, 0.25%, 0.50%, 0.75%, 1 , 00% and 1,25% - v / v), applied weekly with and without mulch. The variables analyzed were plant height, number of leaves, leaf area, specific leaf area, leaf area index, Falker a, b and total chlorophyll index, longitudinal and equatorial diameters of tuberous roots, fresh tuberous root mass, Axial root length, total dry mass, percentage of commercial tuberous roots, productivity and dry matter yield. The use of mulch reduced specific leaf area, fresh matter and radish productivity, regardless of the concentration of cow urine applied. The leaf chlorophyll index of radish was higher in the plants without mulching. Longer radishes were obtained on substrates without mulching or 0.51% cow urine. Possibly, due to the production of secondary metabolites (allelochemicals) from the mulch (rice straw), the application of 0.54% cow urine without mulching provided higher radish productivity. The concentration of cow urine of 0.38% provided higher yields of dry matter.

In vitro metabolism of selected bioactive compounds of Eurycoma longifolia root extract to identify suitable markers in doping control.

Eurycoma longifolia Jack (Tongkat Ali, Simaroubaceae) is a medicinal plant endemic to South-East Asia. For centuries, different parts of the plant have been used as a natural remedy to treat fever, hypertension, or sexual insufficiency. Today, Eurycoma longifolia preparations are commercially available and advertised to enhance athletic performance and muscle strength. Several studies have demonstrated a testosterone-boosting effect that might be caused by the release of free testosterone from the sex-hormone-binding globulin. To date, many phytochemical constituents of Eurycoma longifolia root extracts have been identified and physiological effects have been examined, while studies on their biotransformation and monitoring are still lacking. Within this study, eurycomalide C, eurycomalactone, 5,6-dehydro-eurycomalactone, longilactone, 14,15β-dihydroklaieanone, 11-dehydroklaieanone, 9-hydroxycanthin-6-one, and 9-methoxycanthin-6-one isolated from E. longifolia root were incubated with liver microsomes. Respective metabolites were analyzed by liquid chromatography-tandem (high-resolution) mass spectrometry. The compounds were chosen based on their potential androgenic effects (estimated by in vitro assays), their concentrations in plant extracts, and presumptive metabolic pathways. Hydroxylated phase I metabolites were only observed for 5,6-dehydro-eurycomalactone, 11-dehydroklaieanone, 9-hydroxycanthin-6-one, and 9-methoxycanthin-6-one. Moreover, an O-demethylated metabolite of 9-methoxycanthin-6-one was found. Besides, the glucuronide of 9-hydroxycanthin-6-one was detected after in vitro glucuronidation using liver microsomes. The in vitro generated metabolites were comparable to that detected in urine and serum after a single ingestion of either 9-methoxycanthin-6-one or an Eurycoma longifolia root extract. Hence, 9-methoxycanthin-6-one, its glucuronide, and the glucuronide of its O-demethylated biotransformation product are proposed to be the most suitable targets for detection of 9-methoxycanthin-6-one or Tongkat Ali application in urine and serum.

Does sowing an oats catch crop reduce nitrate leaching from urine deposition following simulated winter forage grazing? - a growth chamber experiment

Growing winter forages, such as brassicas and fodder beets, is a common feed strategy to build body condition for non-lactating cows, prior to calving, in the temperate regions of New Zealand. However, the large quantities of feed grown, ~14-20 tonnes ha-1, and resulting high stocking rates, means large volumes of urine are deposited during grazing, over relatively small areas, on cool, bare and often wet soils. These conditions create a high potential for large N leaching losses. Sowing a catch crop might be one way to mitigate this potential but most catch crops are sown in late-summer/autumn, not late winter/spring, so this study’s objectives were to examine the potential of a cold-tolerant cereal, oats, to establish and take up soil N over this period. A study was undertaken using free-draining repacked soil cores in two climate-controlled growth chambers at 6° and 10°C, and at two lighting intensities, 5 and 10 MJ m-2, reflecting the mean soil temperature (0-100 mm) and light levels experienced in Canterbury, New Zealand, around late winter and mid spring, respectively. The cores all received an application of 15N-labelled urine (350 kg N ha-1) and two weeks later, oats were sown in half the soil cores, with the remainder left fallow. Sowing oats at 6° and 10°C both proved highly effective in reducing nitrate leaching loss by around 33% and 75%, respectively, compared to fallow treatments. Soil temperature, however, was the chief driver of oats development, growing an order of magnitude more rapidly at 10°C and reducing nitrate leaching loss quickly through a combination of increased N uptake and reduced drainage. However, ammonia oxidising bacteria (AOB) abundance in 10°C fallow treatments increased more rapidly after urine application than at 6°C, meaning soil nitrate concentrations rose quickly, leaching twice as much nitrate as the 6°C fallow treatments after 90 days. Greater plant growth (10-times more) at 10°C than at 6°C, 75 days after sowing, was offset to some degree by greater N% and N content in the plant stems and roots at 6°C (2-4 times more). Higher light intensity increased evaporative water loss in both 6° and 10°C chambers, reducing drainage and nitrate leaching, and increasing the rate of oats development at 10°C. The sowing of oats as a catch crop following simulated winter forage grazing conditions shows promise as an effective means to limit nitrate leaching. Further research, however, is needed to show that a catch crop can be sown successfully in most years at farm paddock scale across a range of soil conditions.

Sheep urine patch N2O emissions are lower from extensively-managed than intensively-managed grasslands

A large number of sheep graze extensively managed grasslands, including upland and hill areas. Excretal deposition of nitrogen (N) to upland soil is a potentially large source of the powerful greenhouse gas (GHG), nitrous oxide (N2O), however, few studies have assessed urine-patch N2O emissions from upland areas. Current default excretal N2O emission factors (EFs) are based on intensively managed lowland systems, with cattle excreta as the N source. We hypothesised that N2O emissions could differ substantially from those of lowland systems, due to differences in soil type, climate, topography, pasture composition and management factors along altitudinal and productivity gradients. We investigated N2O emission factors across two seasons (spring and autumn), for an extensive semi-improved, temperate grassland using IPCC-compliant and representative sheep urine patches (in terms of urine chemical composition, urine patch size and N loading rates). An automated GHG monitoring system provided high-frequency GHG data from sheep urine patches (756 and 1112 kg N ha−1 applied in spring and autumn, respectively), reference artificial sheep urine patches (1066 and 1004 kg N ha−1 applied in spring and autumn, respectively) and control treatments. In spring, urine patch N2O emission factors were −0.02 ± 0.04 (artificial sheep urine) and 0.03 ± 0.09% (real sheep urine) of the applied N; in autumn emission factors were 0.02 ± 0.03 (artificial sheep urine) and 0.08 ± 0.04% (real sheep urine) of the applied N. These values are much lower than default inventory values (1% of applied N) for excreta deposited by grazing livestock. There was a greater pasture foliar N content following urine application in spring as opposed to autumn, and a significantly longer residence time of extractable mineral N in autumn. Our findings demonstrate the importance of generating country-specific N2O EFs based on altitude/productivity gradients of livestock production, with implications for national inventories and the accuracy of sustainability metrics of lamb produced in the UK uplands.

The effects of urine and urine-separated plant nutrient sources on growth and dry matter production of perennial ryegrass (Lolium perenne. L)

The use of urine, and urine-derived products can supplement chemical fertilisers. There is little information on the use of urine products in agriculture particularly in South Africa. A laboratory incubation experiment was conducted to determine effects of urine-derived sources on nitrogen (N) release in soil. A 5 × 2 factorial in a completely randomised design was used with two soils, differing in clay and carbon contents, and five nitrogen (N) sources; unamended control, urine, struvite effluent, stuvite + struvite effluent, nitrified urine concentrate. A follow up tunnel pot trial was conducted to determine effects of the urine-derived N sources on dry matter production of perennial ryegrass. The experiment was conducted with the Cartref soil as a 6 × 2 factorial in a completely randomised design, with the same N sources as in the incubation experiment, applied either once-off or split, replicated three times. In the Cartref soil (lower clay and C), ammonium- N declined from 1000 to about 3 mg/kg from day one to day 70, while nitrate- N increased significantly from 0.3 mg/kg to about 400 mg/kg during the same period. Conversely, ammonium-N declined from 100 mg/kg to 8.5 mg/kg in the Inanda soil (higher clay and C), while nitrate- N did not significantly increase. Split application of urine derived N sources resulted in higher cumulative dry matter (873–993 kg/ha) than once-off application (602–727 kg/ha). When split applied only struvite effluent resulted in higher drymatter than struvite effluent + struvite, while once-off application resulted in higher drymatter in the NUC (725 kg/ha) and urine (707 kg/ha) than struvite effluent (602 kg/ha) and struvite effluent + struvite (663 kg/ha). The study indicate that urine derived nitrogen sources, particularly nitrified urine concentrate, can release nitrogen in soil and increase drymatter production of perennial ryegrass, particularly with split application.