Soil CO2 emission in sugarcane management systems

Sugarcane management systems affect soil attributes such as the carbon cycle. This fact has stimulated the sugar and alcohol industry to refine the sugarcane production systems by replacing the pre-harvest burning (PB) and manual harvest with mechanized harvesting followed by residue deposition. The aim of this study was to evaluate different management systems with respect to C cycling carbon dioxide and soil parameters (chemical, physical and biological) which were determined over the season. Three sugarcane cultivation systems were evaluated at the following periods: (a) PB, (b) 5-year green harvest and (c) 10-year green harvest. The results indicated that CO₂ emission was 36% greater in the 10-year sugarcane green harvest system than in the PB system. The bulk density and macroporosity were the factors that were most affected by the different sugarcane management systems and that significantly influenced soil CO₂ emissions. The principal component analysis showed that soil CO₂ emission was 18% influenced by base saturation (V%) and 14% by pH, especially in the PB area. Additionally, 19% was affected by carbon and macroporosity in the 5- and 10-year green harvest areas, respectively. From our results, it can be concluded that the most CO₂ emissions are in the areas of sugarcane green, this is due to the higher carbon concentration when compared with the area of burning sugarcane. The parameters that most influenced the CO₂ emissions were bulk density, porosity, macroporosity, pH and V%.     

Population pharmacokinetics of methadone hydrochloride after a single intramuscular administration in adult Japanese sika deer (Cervus nippon nippon)

ObjectiveTo assess the population pharmacokinetics of methadone in deer.Study designProspective non-randomized experimental trial.AnimalsTwelve healthy adult sika deer (nine males and three females).MethodsDeer received intramuscular administration of racemic methadone hydrochloride at 0.5 mg kg⁻¹ or 1 mg kg⁻¹. Plasma methadone and its metabolite 2-Ethylidene-1,5-Dimethyl-3,3-Diphenyl-Pyrolidine (EDDP) concentrations were determined by validated liquid chromatography coupled to tandem mass spectrometry methods, at times 0, 30 minutes, 1, 2, 3, 4, 5, 6, 8, 12 and 24 hours. Population pharmacokinetics analysis was undertaken using a non-linear mixed effects modelling (NONMEM).ResultsA two-compartment linear disposition model best described observed time-concentration profiles of methadone and EDDP. Population parameter estimates of methadone were elimination clearance (17.3 L hour⁻¹), metabolic clearance (34.6 L hour⁻¹), volume of distribution of compartment 1 (216.0 L) and volume of distribution of compartment 2 (384.0 L). Population parameter estimates of EDDP were elimination clearance (121.0 L hour⁻¹), volume of distribution of compartment 3 (1.08 L) and volume of distribution of compartment 4 (499.5 L). The total clearance and total volume of distribution of methadone and EDDP were 51.9 L hour⁻¹, 121.0 L hour ⁻¹, 600.0 L and 500.6 L, respectively. The methadone terminal elimination half-life was 8.19 hours. No adverse effects were observed after methadone administration.Conclusions and Clinical relevanceFollowing intramuscular injection, methadone was characterized by a large total volume of distribution, high systemic clearance and intermediate terminal half-life in sika deer.     

Factors that contribute to the mycoparasitism stimulus in Trichoderma atroviride strain P1

Trichoderma atroviride strain P1 has been used extensively to study the mycoparasitic mechanisms in the interaction between plant pathogenic host and beneficial antagonistic fungi. Mutants of P1 containing the green fluorescent protein (gfp) or glucose oxidase (gox) reporter systems and different inducible promoters (from the exochitinase nag1 gene, or the endochitinase ech42 gene of P1) were used to determine the factors that activate the biocontrol gene expression cascade in the antagonis…     

G protein signalling involved in host recognition and mycoparasitismrelated chitinase expression in Trichoderma atroviride

Mycoparasitic species of Trichoderma are commercially applied as biological control agents against various fungal pathogens. The mycoparasitic interaction is host specific and includes recognition, attack and subsequent penetration and killing of the host. Investigations on the underlying events revealed that Trichoderma responds to multiple signals from the host (e.g. lectins or other ligands such as low molecular weight components released from the host's cell wall) and host attack is ac…     

Carbon dioxide emissions after application of tillage systems for a dark red latosol in southern Brazil

Soil tillage may influence CO₂ emissions in agricultural systems. Agricultural soils are managed in several ways in Brazil, ranging from no tillage to intensive land preparation. The objective of this study was to determine the effect of common soil tillage treatments (disk harrow, reversible disk plow, rotary tiller and chisel plow tillage systems) on the intermediate CO₂ emissions of a dark red latosol, located in southern Brazil. Different tillage systems produced significant differences in the CO₂ emissions, and the results indicate that the chisel plow produced the highest soil carbon loss during the 15 days period after tillage treatments were performed. Emissions to the atmosphere increased as much as 74 g CO₂ m⁻², at the end of a 2-week period, in the plot where the chisel plow treatment was applied, in comparison to the non-disturbed plot. The results indicate that the total increase on the intermediate term soil CO₂ emissions due to tillage treatments in southern Brazil is comparable to that reported for the more humid and cooler regions.     

Sur l'Involution de la Bourse de Fabricius chez le Canard

On the involution of the bursa of Fabricius of the duck
The morphological and structural aspects of the functional aspects of the involution were studied light- and electronmicroscopically in ducks 90 to 150 days old. The first involutionary changes were observed in the interfollicular connective tissue around day 100. Following this, cells left the periphery of the follicles; they were connected with collagen fibers and positioned themselves between the lymphocytes of the cortex that became thinner before it disappeared.
On day 135 the medulla lost its lymphocyte content through wide ducts which opened directly into the lumen of the bursa. On day 150 the bursa experienced a massive overgrowth; almost all follicles had disintegrated and only small groups of cells remained which consisted principally of reticuloepithelial cells and some lymphocytes.
Cysts were not observed during the involution of the bursa.     

Sero-epidemiological survey of Neospora caninum infection in dogs in north-eastern Italy

Risk factors associated with Neospora caninum seroprevalence in north-eastern Italy in healthy dogs were assessed. Antibodies to N. caninum were found in 10.9% of 707 kennel and owned dogs by a commercial competitive ELISA (VMRD Inc.). All dogs were negative for Leishmania infantum by indirect fluorescent antibody test indicating no cross reactivity or association between the two protozoa in this area. Seroprevalence association with breed and age of dogs and other factors are discussed.     

The influence of flotation solution, sample dilution and the choice of McMaster slide area (volume) on the reliability of the McMaster technique in estimating the faecal egg counts of gastrointestinal strongyles and Dicrocoelium dendriticum in sheep

The present study was aimed to evaluate the influence of flotation solution, sample dilution, and the choice of McMaster slide area (volume) on the reliability of the McMaster technique in estimating the faecal egg counts of gastrointestinal (GI) strongyles and Dicrocoelium dendriticum in a composite sample of faeces from naturally infected sheep. Fourteen flotation solutions having densities between 1.200 and 1.450, and six sample dilutions, 1:10, 1:15, 1:20, 1:30, 1:40 and 1:50 were used. Each of the six dilutions was divided into 70 aliquots in order to have five replicates of each of the 14 flotation solutions at each of the six dilutions. For each McMaster slide, the GI strongyle and D. dendriticum egg counts were performed under one grid (McM 0.15 ml), two grids (McM 0.3 ml), one chamber (McM 0.5 ml), and both chambers (McM 1.0 ml). Mean eggs per gram (EPG) of faeces of GI strongyles and D. dendriticum were calculated and statistical analyses were performed on the resulting data. The type of flotation solution used significantly influenced the EPG in the GI strongyles and in the D. dendriticum egg counts. All the sucrose-based solutions at density between 1.200 and 1.350 floated more GI strongyle eggs than the others. With respect to D. dendriticum, only six solutions were capable of floating eggs and the potassium iodomercurate solution (density 1.440) floated more eggs than the others. The reliability of the McMaster technique regarding sample dilution was high for both GI strongyle and D. dendriticum EPG at 1:10 and 1:15, and then progressively decreased with increasing dilution. The reliability of the McMaster technique regarding the choice of the McMaster slide area (volume) was high for both GI strongyle and D. dendriticum EPG at the McMaster slide area (volume) of 1.0 ml, i.e. the total area of the McMaster slide. The EPG counts resulting from choosing any of the other three McMaster slide areas (volumes), i.e. McM 0.15 ml, McM 0.3 ml, or McM 0.5 ml, produced unreliable over-estimates. The findings of the present study show that the highest reliability of the McMaster technique for estimating GI strongyle and D. dendriticum egg counts in faeces from pastured sheep is obtained when using flotation solutions based on sucrose for GI strongyles, and potassium iodomercurate for D. dendriticum, dilutions which do not exceed 1:15, and the McMaster slide area (volume) of 1.0 ml.     

Reticular Groove of the Domestic Ruminants: Histochemical and Immunocytochemical Study

The reticular groove mucosa of adult cattle, buffalo and sheep was investigated by histochemical and immunocytochemical techniques. Intense NADPH‐d staining was observed in the folds of the epithelium mucosa and at the bottom of the reticular groove in all domestic ruminants studied. The NADPH‐d staining showed that the innervations of the tunica muscularis of the reticular groove lip were composed of nerve corpuscles, nerve fibres and nerve cells of the mucosa epithelium. SEM analysis showed an intense nitric oxide synthase (NOS) I immunoreactivity in deep and medium cellular layers. It is interesting to note that the same morphologies were observed in samples of the mucosa epithelium, and of the tunica muscularis processed by NADPH‐d and in those processed by immunogold techniques. This study has demonstrated that nitric oxide (NO) is involved in the rumination activity and that it plays a double role in this activity in the reticular groove of all domestic ruminants studied: (1) NO plays a role similar to the one it has in the mucosa epithelium of all the other compartments of the ruminant forestomach, (2) The lip sections of the reticular groove has shown abundant innervations that may indirectly coordinate and control the forestomach motility through the direct activation of the nitrergic (nitroxidergic) nerve cells and nerve fibres.