Viability assessment of spermatozoa in large falcons (Falco spp.) using various staining protocols

Viability assessment is an important part of semen analysis, and various live/dead staining protocols have been used in semen of avian species. Results of live/dead count differed between dyes, staining protocols and bird species, impeding comparability between studies and requiring species-specific comparisons of viability stains. In raptor semen, similar comparisons are absent. Thus, the aim of the present study was to compare eight conventional viability stains. Eosin blue 2% [EB], eosin blue 2% with the addition of 3% sodium citrate [EB2], eosin blue–nigrosin 5% [EBN5], eosin yellow–nigrosin 5% [EYN5], eosin yellow–nigrosin 10% [EYN10], eosin blue–aniline blue [EBA], eosin yellow–aniline blue [EYA] and bromophenol blue–nigrosin [BBN] were evaluated in comparison with the fluorescence stain SYBR^® Green–propidium iodide [SYBR-PI] in spermatozoa of falcons. The comparison was performed using conventional light microscopy which is applicable in breeding centres, veterinary practices and field studies. Additionally, live/dead stains were correlated to motility values of the same samples to validate sperm viability. Light microscopy using EB and using SYBR-PI enabled an effective and clear differentiation between alive and dead spermatozoa of falcons. Motility values correlated significantly and strongly with EB only (r = .629; p < .001), but not with any other stain used in the study. Therefore, our results suggest EB as the most suitable stain for viability assessment in the semen of large falcons.     

Identifying, managing and monitoring conflicts between forest biodiversity conservation and other human interests in Europe

In this paper, circumstances where various human activities and interests clash with the conservation of forest biodiversity are examined, with particular focus on the drivers behind the conflicts. After identifying past and current human-related threats potentially leading to conflicts in forests, the paper will focus on conflict management and monitoring, with an emphasis on inclusionary stakeholder networks and a range of approaches towards sustainable land use. Three dimensions of conflicts are examined: substance (‘how things are’), procedure (‘how things are done’), and relationships (‘how people behave’). These relations will relate to three conflict management approaches: (1) technical, which may contribute to reduce or solve the conflict acting on the ‘substance’ dimension, (2) political, which may influence the ‘procedure’ dimension of the conflict establishing principles or rules, and (3) cultural, which may affect the ‘relationship’ dimension of the conflict. Finally, a general model of adaptive conflict management emphasising communication among the parties and a participatory approach that involves monitoring of the conflict resolution outcomes is proposed. The recognition that strong perceptions among stakeholders have the potential to aggravate conflicts is central to the concept of a inclusionary conflict management framework, improved communication between all stakeholders, and better awareness of the context of the conflicts is emphasised.     

Hydraulic variability in space and time in a dark red latosol of the tropics

Detailed information of the variability of soil properties and processes in space and time is presented for a dark red latosol (Alfisol) of the county of Piracicaba, S.P., Brazil. Data were collected on 25 plots along a 125 m transect during the years 1989–1991, and consisted of the soil water content θ in the 0–150 cm soil layer and the water pressure heads h at 135 and 165 cm depths. These raw data were used to characterize variabilities in space and time using classical statistics and in a second step to analyse the difficulties in calculating soil water storage, soil hydraulic conductivities, hydraulic gradients, soil water fluxes and water balances. In general, there was a great variability of hydraulic properties and processes, which is fairly constant in time in the case of basic data like soil water content and potential, but not in the case of calculated data like hydraulic conductivities and gradients, and soil water flux densities. A discussion is presented of the difficulties of using Darcy's equation to estimate soil water flux densities due to the exponential K(θ) and K(h) relationships of the hydraulic conductivity K, and of the influence of variability in space and time on the establishment of water balance components.     

Genetic regulation of growth and nutrient content under phosphorus deficiency in the wild barley introgression library S42IL

Phosphorus (P) is an important macronutrient required for plant growth and yield formation. Since decades, breeders aim to optimize P efficiency in crops. We studied a set of 47 wild barley (Hordeum vulgare ssp. spontaneum, Hsp) introgression lines (ILs) in hydroponic culture to identify quantitative trait loci (QTLs) improving growth and nutrient content under P deficiency. Applying a mixed model analysis, a total of 91 independent QTLs were located among 39 ILs, of which 64 QTLs displayed trait‐improving Hsp effects. For example, an unknown Hsp allele on barley chromosome 4H increased shoot dry weight under P deficiency in three overlapping ILs by 25.9%. Likewise, an Hsp allele on barley chromosome 6H increased root dry weight under P deficiency in two overlapping ILs by 27.6%. In total, 31 QTLs confirmed Hsp effects already identified in previous field and glasshouse experiments with the same ILs. We conclude that wild barley contains numerous trait‐improving QTL alleles, which are active under P deficiency. In future, the underlying genes can be subjected to cloning and, simultaneously, used in elite barley breeding.     

Intermittent positive pressure ventilation with constant positive end-expiratory pressure and alveolar recruitment manoeuvre during inhalation anaesthesia in horses undergoing surgery for colic, and its influence on the early recovery period

Objective To compare, ventilation using intermittent positive pressure ventilation (IPPV) with constant positive end‐expiratory pressure (PEEP) and alveolar recruitment manoeuvres (RM) to classical IPPV without PEEP on gas exchange during anaesthesia and early recovery. Study design Prospective randomized study. Animals Twenty‐four warm‐blood horses, weight mean 548 ± SD 49 kg undergoing surgery for colic. Methods Premedication, induction and maintenance (isoflurane in oxygen) were identical in all horses. Group C (n = 12) was ventilated using conventional IPPV, inspiratory pressure (PIP) 35–45 cmH₂O; group RM (n = 12) using similar IPPV with constant PEEP (10 cmH₂O) and intermittent RMs (three consecutive breaths PIP 60, 80 then 60 cmH₂O, held for 10–12 seconds). RMs were applied as required to maintain arterial oxygen tension (PaO₂) at >400 mmHg (53.3 kPa). Physiological parameters were recorded intraoperatively. Arterial blood gases were measured intra‐ and postoperatively. Recovery times and quality of recovery were measured or scored. Results Statistically significant findings were that horses in group RM had an overall higher PaO₂ (432 ± 101 mmHg) than those in group C (187 ± 112 mmHg) at all time points including during the early recovery period. Recovery time to standing position was significantly shorter in group RM (49.6 ± 20.7 minutes) than group C (70.7 ± 24.9). Other measured parameters did not differ significantly. The median (range) of number of RMs required to maintain PaO₂ above 400 mmHg per anaesthetic was 3 (1–8). Conclusion Ventilation using IPPV with constant PEEP and RM improved arterial oxygenation lasting into the early recovery period in conjunction with faster recovery of similar quality. However this ventilation mode was not able to open up the lung completely and to keep it open without repeated recruitment. Clinical relevance This mode of ventilation may provide a clinically practicable method of improving oxygenation in anaesthetized horses.     

Influence of xylazine on the function of the LiDCO sensor in isoflurane anaesthetized horses

ObjectivePrevious studies showed an influence of xylazine on the LiDCO sensor in vitro and in standing horses, but did not prove that this interaction caused error in LiDCO measurements. Therefore, agreement of cardiac output (CO) measurements by LiDCO and bolus-thermodilution (BTD) was determined in horses receiving xylazine infusions.Study designProspective, experimental study.AnimalsEight Warmblood horses.MethodsAll horses were premedicated with xylazine. Anaesthesia was induced with midazolam and ketamine and was maintained with isoflurane in oxygen. During six hours of anaesthesia CO measurements and blood samples were taken before, during and after a 60 minute period of xylazine infusion. Pairs of LiDCO and bolus thermo-dilution (BTD) measurements of CO were performed. Sensor voltages exposed to blood and saline were measured before, during and after xylazine infusion and compared using Bland-Altman method of agreement with corrections for repeated measures.ResultsThe CO values (mean ± SD) before xylazine were 34.8 ± 7.3 and 36.4 ± 8.1 L minute⁻¹ for BTD and LiDCO, respectively. After starting the xylazine infusion, the CO values for BTD decreased to 27.5 ± 6.1 L minute⁻¹ whereas CO values measured by LiDCO increased to 54.7 ± 18.4 L minute⁻¹. One hour after discontinuing xylazine infusion, CO values were 33 ± 6.7 and 36.5 ±11.9 L minute⁻¹ for BTD and LiDCO, respectively. The difference between saline and blood exposed sensor voltages decreased during xylazine infusion and these differences were positive numbers before but negative during the infusion. There were correlations between xylazine plasma concentrations, CO differences and sensor voltage differences (saline – blood).Conclusions and clinical relevanceThis study proved that xylazine infusion caused concentration dependent bias in LiDCO measurements leading to an overestimation of readings. Sensor voltage differences (saline – blood) may become valuable clinical tool to predict drug-sensor interactions.     

Climate Projections Using Bayesian Model Averaging and Space–Time Dependence

Projections of future climatic changes are a key input to the design of climate change mitigation and adaptation strategies. Current climate change projections are deeply uncertain. This uncertainty stems from several factors, including parametric and structural uncertainties. One common approach to characterize and, if possible, reduce these uncertainties is to confront (calibrate in a broad sense) the models with historical observations. Here, we analyze the problem of combining multiple climate models using Bayesian Model Averaging (BMA) to derive future projections and quantify uncertainty estimates of spatiotemporally resolved temperature hindcasts and projections. One advantage of the BMA approach is that it allows the assessment of the predictive skill of a model using the training data, which can help identify the better models and discard poor models. Previous BMA approaches have broken important new ground, but often neglected space–time dependencies and/or imposed prohibitive computational demands. Here we improve on the current state-of-the-art by incorporating space–time dependence while using historical data to estimate model weights. We achieve computational efficiency using a kernel mixing approach for representing a space–time process. One key advantage of our new approach is that it enables us to incorporate multiple sources of uncertainty and biases, while remaining computationally tractable for large data sets. We introduce and apply our approach using BMA to an ensemble of Global Circulation Model output from the Intergovernmental Panel on Climate Change Fourth Assessment Report of surface temperature on a grid of space–time locations.     

Application of mixed straw and biochar meets plant demand of carbon dioxide and increases soil carbon storage in sunken solar greenhouse vegetable production

Solar vegetable greenhouse soils show low soil organic carbon content and thus also low rates of soil respiration. Processing vegetable residues to biochar and mixing biochar with maize straw might improve soil respiration and increase soil organic carbon stocks, while preventing the spread of soil-borne diseases carried by vegetable residues. In an incubation experiment, we tested how additions of maize straw (S) and biochar (B) added in varying ratios (100S, 75S25B, 50S50B, 25S75B, 100B and 0S0B (control)) affect soil respiration and fraction of added C remaining in soil. Daily CO₂ emissions were measured over 60 days incubation, the natural abundance of ¹³C in soil and in the added biochar and maize straw were analysed. Our result shows that (a) soil CO₂ emissions were significantly increased compared to soil without the straw additions, while addition of biochar only decreased soil respiration; (b) cumulative CO₂ emissions decreased with increasing ratio of added biochar to maize straw; (c) the abundance of soil ¹³C was significant positively correlated with cumulative CO₂ emissions, and thus with the ratio of straw addition. Our results indicate that incorporation of maize straw in greenhouse soils is a meaningful measure to increase soil respiration and to facilitate greenhouse atmosphere CO₂ limitation while producing vegetables. On the other hand, additions of biochar from vegetable residues will increase soil organic carbon concentration. Therefore, the simultaneous application of maize straw and biochar obtained from vegetable residues is an effective option to maintain essential soil functions for vegetable production in sunken solar greenhouses.     

Soil dissolved organic carbon responses to sugarcane straw removal

Global demand for bioenergy increases interest in biomass‐derived fuels, as ethanol from sugarcane straw. However, straw is the main carbon source to soil and its removal reduces C input, affecting active fractions (dissolved organic carbon, DOC) and C storage. To quantify the effects of straw removal on DOC and C stocks, we built lysimeter system using soil (Rhodic Kandiudox) from sugarcane field. We evaluated four soil depths (1, 20, 50 and 100 cm) and four straw removal rates: no removal NR, medium MR, high HR and total TR, leaving 12, 6, 3 and 0 Mg/ha on the soil surface, respectively. After rainfall, drainage water was collected and analysed for DOC content. Soil C stocks were determined after the 17‐month. Total DOC released at 1‐cm depth amounted to 606, 500, 441 and 157 kg/ha in NR, MR, HR and TR, respectively. Net‐DOC suggests straw as the main source of DOC. Most of DOC in NR (50%) was retained within the 1–20 cm layer, resulting in higher C stock (10 Mg/ha) in the topsoil. In HR and MR, DOC retention was higher within 20–50 cm, suggesting differences in DOC composition. DOC in TR was 40% higher at 20 cm than at 1 cm, indicating C losses from topsoil. Low concentrations of DOC were found at 100‐cm depth, but representing 30% in TR. Straw removal for bioenergy production is sustainable, but we should leave at least 3 Mg/ha of straw to ensure DOC production and soil C storage, taking account the DOC contribution to key soil functions.