U.S. cereal rye winter cover crop growth database.

Winter cover crop performance metrics (i.e., vegetative biomass quantity and quality) affect ecosystem services provisions, but they vary widely due to differences in agronomic practices, soil properties, and climate. Cereal rye (Secale cereale) is the most common winter cover crop in the United States due to its winter hardiness, low seed cost, and high biomass production. We compiled data on cereal rye winter cover crop performance metrics, agronomic practices, and soil properties across the eastern half of the United States. The dataset includes a total of 5,695 cereal rye biomass observations across 208 site-years between 2001-2022 and encompasses a wide range of agronomic, soils, and climate conditions. Cereal rye biomass values had a mean of 3,428 kg ha-1, a median of 2,458 kg ha-1, and a standard deviation of 3,163 kg ha-1. The data can be used for empirical analyses, to calibrate, validate, and evaluate process-based models, and to develop decision support tools for management and policy decisions.

Forage and tree seedling growth in a soil with an encased swine sludge layer.

The closure of swine farms requires decommissioning of lagoons that contain large amounts of swine solids (sludge). Sludge is typically transported and land applied to soils. However, in some cases this process could be economically prohibitive and/or unpractical. An alternative idea is to encase sludge with lagoon soil berms after removing overlying effluent, followed by establishment of forages or short-rotation woody crops on the encased sludge. The objective of this study was to investigate growth potential for several forages and tree species into a pure layer of swine sludge. Alfalfa (Meticago sativa), bermudagrass (Cynodon dactylon), switchgrass (Panicum virgatum), green ash (Fraxinus pennsylvanica), black locust (Robinia pseudoacacia), and sycamore (Platanus occidentalis) were established in 40 cm deep pots consisting of a lagoon berm soil overlaying a sludge layer for 12 w followed by analysis of aboveground and belowground biomass production. "New" and "old" sludge was collected from an active 10 year old lagoon and decommissioned 50 year old lagoon, respectively. A control (soil only) was used. Encased sludge treatments increased forage biomass production. Sycamore and green ash were sensitive to new sludge but not old sludge as these species had less biomass production in new sludge than control and showed tissue trace nutrient deficiencies. While both sludge materials contained adequate nutrients, the new sludge had a salt concentration 1.8 times higher than old sludge as indicated by electrical conductivity (12.4 mS). Thus, the forage crops and black locust were able to thrive in new sludge due to their salt tolerance.

Subarachnoid hemorrhage and axonal degeneration after C1-C2 cervical centesis in 2 horses.

Ultrasound-guided cervical centesis has gained popularity as a method for collecting cerebrospinal fluid (CSF) from standing horses. There are anecdotal reports of neck stiffness, regional swelling, sensitivity to palpation, and fever after the procedure. We report 2 horses with complications that occurred within days of C1-C2 centesis and ultimately resulted in euthanasia. Both C1-C2 centesis were performed routinely, with CSF cytologic analysis providing no evidence of blood contamination. Post-mortem examination revealed equine degenerative myeloencephalopathy as the primary disorder causing Horse 1's initial neurologic deficits, whereas Horse 2 did not have a distinct lesion explaining the horse's deficits. Both horses had evidence of subarachnoid hemorrhage at or near the centesis site with Wallerian axonal degeneration in the cranial cervical spinal cord. Although hemorrhage with associated axonal degeneration at the cervical centesis site appears to be rare, this complication of C1-C2 centesis should be considered as this technique gains popularity.

Soil microbial community development across a 32-year coastal wetland restoration time series and the relative importance of environmental factors.

Soil microbes play key roles in ecosystem functioning through processes such as organic matter decomposition, nutrient and carbon cycling, and regulating vegetation structure and productivity. Coastal marshes are situated at the confluence of terrestrial and marine ecosystems; thus, their soils support abundant and diverse microbiota which facilitate globally important biogeochemical processes including nutrient cycling and greenhouse gas fluxes. With coastal marsh ecosystems threatened by relative sea level rise, subsidence, and development, mitigation for the loss of marshes is becoming commonplace. Despite the widespread implementation of marsh construction projects, little is known about the development and variability of microbial communities in created marshes. For this study, we tested the hypothesis that microbial community composition differs across created marshes of different ages and between created and natural marshes. We also hypothesized that the microbial community would be correlated with soil properties including soil organic carbon and nitrogen content, which were predicted to increase with marsh age. To test these hypotheses, we determined dominant microbial groups and environmental characteristics from six constructed marshes ranging in age from 0 to 32 years old, as well as an adjacent natural marsh. Our results revealed that microbial biomass estimates increased with marsh age except for the high elevation 20-year old marsh, yet each marsh contained a distinct microbial community composition. Across marshes, microbial community composition was significantly related to soil C:N ratio with an increase in total microbial abundance and actinomycetes and GM+ bacteria with an increase in soil C to N ratio. Additionally, shifts in dominant microbial groups were associated with differences in vegetation, elevation, and marsh age. The natural marsh community grouped more closely with younger rather than older marshes suggesting age is less important than environmental conditions. This study shows that microbial communities are not homogenized across restoration sites and do not necessarily converge to be similar to natural marshes over time. Local biotic and environmental conditions were correlated with microbial compositions, yet in seemingly similar conditions, microbial groups also differed. The effect of differences in microbial compositions on ecological functions are yet to be fully understood.

Application of biochar in estrogen hormone-contaminated and manure-affected soils: Impact on soil respiration, microbial community and enzyme activity.

Biochar as a soil amendment has been proposed for enhancing carbon sequestration and manure-borne hormone contaminant remediation. However, little is known about the ecological risk of biochar application in the soil with hormone contamination. This study investigated the influence of biochar in three manure-impacted soils contaminated with estrogen hormones, natural estrogen 17ß-estradiol and synthesized estrogen 17α-ethinylestradiol in a microcosm experiment. Specifically, microbial respiration was periodically determined during microcosm incubation while microbial community phospholipid fatty acids and activities of nutrient (C, N, P, S) cycling related enzymes (ß-glucosidase, urease, phosphodiesterase, arylsulfatase) were characterized after the incubation. Results showed that the manure-impacted soils with high SOC generally had greater total microbial biomass, ratios of fungi/bacteria and Gram-positive bacteria/Gram-negative bacteria, and phosphodiesterase activity, but lower urease activity. Additionally, hormones stimulated microbial respiration and biomass, while had little impact on activity of the enzymes. On the other hand, biochar showed negative priming effect by significantly decreasing total microbial biomass by 8.7%-26.4%, CO2 production by 16.6%-33.5%, and glucosidase activity by 27.1%-41.0% in the three soils. Biochar significantly increased the activity of phosphodiesterase, showed no impact on arylsulfatase, while decreased the activity of urease. Overall, the study suggests that when used in hormone remediation in manure-impact soils, biochar could improve phosphodiesterase activity, but may decrease soil microbial activity and the activity of soil glucosidase and urease.

Remediation of crude oil-contaminated coastal marsh soil: Integrated effect of biochar, rhamnolipid biosurfactant and nitrogen application.

Decontamination of oil spills from coastal wetland soils requires a delicate approach. A microcosm study was carried out to investigate the impact of integrated application of biochar, rhamnolipid (RL) biosurfactant and nitrogen (N) on petroleum hydrocarbon remediation in a Louisiana coastal saline marsh and their impact on soil microbial community. The soil was artificially contaminated with crude oil and subjected to treatments of different combinations of sugarcane residue biochar, RL, and coated urea. Total petroleum hydrocarbons (TPH) in the contaminated soil were analyzed periodically using gas chromatograph and associated soil bacterial community was studied using 16 s rRNA sequencing technologies. Results showed that integrated application of biochar + RL, biochar + N, and biochar + N+RL reduced 32.3%, 73.2%, 80.9% of TPH, respectively, and exhibited synergic interaction with higher efficiency than application individually. Combined treatments showed distinct functions that biochar increased the sorption of aromatic compounds, while RL and N enhanced the degradation of heavy and light aliphatic compounds. All remediation treatments caused reduction of soil bacterial diversity while RL and N shifted the microbial community to higher abundances of Proteobacteria and Bacteroidetes, respectively. Overall, the findings of this study demonstrate the positivity of applying integrated biochar, biosurfactant, and N treatment in oil remediation in wetland soils.

Potential use of biochar and rhamnolipid biosurfactant for remediation of crude oil-contaminated coastal wetland soil: Ecotoxicity assessment.

Remediation of wetland soils contaminated with petroleum hydrocarbons is a challenging task. Biosurfactant and biochar have been used in oil remediation. However, little is known about the ecotoxicity of these materials when applied in wetland ecosystems. In this study, the ecotoxicity of biochar and rhamnolipid (RL) biosurfactant as crude oil remediation strategies in a Louisiana wetland soil was investigated. A pot experiment was set up with wetland soil treated with/without crude oil followed by subjecting to application of 1% biochar and various levels of RL ranging from 0.1% to 1.4%. The ecotoxicity was evaluated regarding to high plant (S. Alterniflora), algae, and soil microbes. Specifically, after a 30-day growth in a controlled chamber, plant biomass change as well as shoot/root ratio was measured. Algae growth was estimated by quantifying chlorophyll by spectrometry following separation, and soil microbial community was characterized by phospholipid fatty acids analysis. Results showed that plant can tolerate RL level up to 0.8%, while algae growth was strongly inhibited at RL > 0.1%. Algal biomass was significantly increased by biochar, which offset the negative impact of oil and RL. Additionally, soil microbial community shift caused by crude oil and RL was alleviated by biochar with promoting Gram-positive bacteria, actinomycetes, and arbuscular mycorrhizal fungi. Overall, this study shows that integrated treatment of biochar and RL has the lowest ecotoxicity to plant and algae when used in oil remediation of contaminated wetland soils.

Exploring anaerobic CO2 production response to elevated nitrate levels in Gulf of Mexico coastal wetlands: Phenomena and relationships.

Recent studies have shown the effect of nitrate (NO3-) on carbon gas emissions from wetland soils that contradict thermodynamic predictions. In this study, CO2 production in three Mississippi River deltaic plain wetland soils (forest swamp, freshwater and saline marshes) with the presence of different NO3- levels (0.2, 2.0, and 3.2 mM) was evaluated in an anaerobic microcosm. Molecular composition of dissolved organic matter (DOM) of these soils was investigated using pyrolysis-GC/MS, and soil microbial community was characterized based on phosphorus lipid fatty acid (PLFA) method to elucidate the underlying mechanisms. Addition of NO3- promoted CO2 production in swamp forest soil, but inhibited CO2 emission from marsh soils. Pyrolysis-GC/MS analysis showed that swamp soil contained more polysaccharides, whereas both marsh soils had high abundance of phenolic compounds. Total PLFAs of forest swamp soil were 34% and 66% higher than freshwater and saline marsh soils, respectively. The PLFA profiles indicated different microbial distribution along a salinity gradient with the forest swamp having a higher proportion of fungi and NO3- reducers but lower sulfate (SO42-) reducers than marsh soils. Overall, the study indicated that the inherent differences in soil DOM and microbial community led to the contrasting response in soil CO2 respiration between forest swamp and marsh ecosystems to NO3- loading. These differences should be considered in determining the fate of nitrate entering Louisiana coastal wetlands from river diversions and other sources and their management.

Viral testing of 18 consecutive cases of equine serum hepatitis: A prospective study (2014-2018).

BACKGROUND: Three flaviviruses (equine pegivirus [EPgV]; Theiler's disease-associated virus [TDAV]; non-primate hepacivirus [NPHV]) and equine parvovirus (EqPV-H) are present in equine blood products; the TDAV, NPHV, and EqPV-H have been suggested as potential causes of serum hepatitis. OBJECTIVE: To determine the prevalence of these viruses in horses with equine serum hepatitis. ANIMALS: Eighteen horses diagnosed with serum hepatitis, enrolled from US referral hospitals. METHODS: In the prospective case study, liver, serum, or both samples were tested for EPgV, TDAV, NPHV, and EqPV-H by PCR. RESULTS: Both liver tissue and serum were tested for 6 cases, serum only for 8 cases, and liver only for 4 cases. Twelve horses received tetanus antitoxin (TAT) 4-12.7 weeks (median = 8 weeks), 3 horses received commercial equine plasma 6-8.6 weeks, and 3 horses received allogenic stem cells 6.4-7.6 weeks before the onset of hepatic failure. All samples were TDAV negative. Two of 14 serum samples were NPHV-positive. Six of 14 serum samples were EPgV-positive. All liver samples were NPHV-negative and EPgV-negative. EqPV-H was detected in the serum (N = 8), liver (N = 4), or both samples (N = 6) of all 18 cases. The TAT of the same lot number was available for virologic testing in 10 of 12 TAT-associated cases, and all 10 samples were EqPV-H positive. CONCLUSIONS AND CLINICAL IMPORTANCE: We demonstrated EqPV-H in 18 consecutive cases of serum hepatitis. EPgV, TDAV, and NPHV were not consistently present. This information should encourage blood product manufacturers to test for EqPV-H and eliminate EqPV-H-infected horses from their donor herds.

Comparison of phenylephrine administration and exercise versus phenylephrine administration and a rolling procedure for the correction of nephrosplenic entrapment of the large colon in horses: 88 cases (2004-2010).

OBJECTIVE: To compare the outcome of horses with nephrosplenic entrapment of the large colon (NSELC) that were treated nonsurgically by IV administration of phenylephrine and exercise with that of horses treated by IV administration of phenylephrine and a rolling procedure under general anesthesia. DESIGN: Retrospective case series. ANIMALS: 88 horses with NSELC. PROCEDURES: Horses examined between 2004 and 2010 because of acute abdominal pain that had NSELC on the basis of findings on abdominal palpation per rectum, abdominal ultrasonography, or both were included. Medical records were reviewed to obtain information on treatment (IV administration of phenylephrine and exercise vs IV administration of phenylephrine and a rolling procedure) and outcome. RESULTS: Overall, 85% (75/88) of horses with NSELC responded to exercise or rolling under general anesthesia. The success rate of rolling under general anesthesia (42/50 [84%]) was significantly higher than the success rate of exercise after IV administration of phenylephrine (24/38 [63.2%]). Resolution of NSELC was achieved by rolling under general anesthesia in 8 of 14 horses that initially failed to resolve with exercise. CONCLUSIONS AND CLINICAL RELEVANCE: A rolling procedure performed under general anesthesia had a higher success rate than exercise after IV phenylephrine administration for resolution of NSELC in horses, suggesting that rolling could be considered as the initial medical treatment. The rolling procedure may be labor intensive and should only be attempted in a surgical facility in the event that exploratory laparotomy is required.

Effects of two commercially available immunostimulants on leukocyte function of foals following ex vivo exposure to Rhodococcus equi.

The objective of this study was to determine the effect of immunostimulants on neutrophil, macrophage, and lymphocyte function following ex vivo exposure to Rhodococcus equi. Eighteen foals were randomly assigned to one of 3 treatment groups. Treatment consisted of inactivated Propionibacterium acnes (PA), inactivated parapoxvirus ovis (PPVO), or saline (control) administered on days 0 (7 days of age), 2, and 8. Bronchoalveolar lavage (BAL) fluid and blood were collected on days 0 (baseline), 12, 24 and 36. Intracellular replication of R. equi in macrophages, cytokine induction by R. equi-infected macrophages, phagocytic and oxidative burst activity of neutrophils, lymphoproliferative responses, and cytokine induction of proliferating lymphocytes were measured. Neutrophils from foals treated with PPVO had significantly greater ability to phagocytize R. equi and undergo oxidative burst on day 12 and day 24 compared to baseline values. On day 24, foals treated with PPVO had significantly greater phagocytosis and oxidative burst than foals treated with PA. Treatment with PA resulted in significantly less intracellular proliferation of R. equi within monocyte-derived macrophages on day 12 compared to control foals. The ability of R. equi to replicate in BAL macrophages decreased significantly (P=0.005) with time with lower replication in BAL macrophages of older foals compared to younger foals, regardless of treatment. On day 12, TNF-α induction in monocyte-derived macrophages and IL-12 p40 induction in BAL macrophages infected with R. equi was significantly higher in foals treated with PPVO than in controls. Lymphoproliferative responses and IFN-γ induction were not significantly different between groups.