Fructans, which are β-(2,1) and/or β-(2,6) linked polymers of fructose, are important storage carbohydrates in many plants. They are mobilized via fructan exohydrolases (FEHs). The cloning, mapping, ...and functional analysis of the first 1-FEH (EC 3.2.1.153) from Lolium perenne L. var. Bravo is described here. By screening a perennial ryegrass cDNA library, a 1-FEH cDNA named Lp1-FEHa was cloned. The Lp1-FEHa deduced protein has a low iso-electric point (5.22) and it groups together with plant FEHs and cell-wall type invertases. The deduced amino acid sequence shows 75% identity to wheat 1-FEH w2. The Lp1-FEHa gene was mapped at a distal position on the linkage group 3 (LG3). Functional characterization of the recombinant protein in Pichia pastoris demonstrated that it had high FEH activity towards 1-kestotriose, 1,1-kestotetraose, and inulin, but low activity against 6-kestotriose and levan. Like other fructan-plant FEHs, no hydrolase activity could be detected towards sucrose, convincingly demonstrating that the enzyme is not a classic invertase. The expression pattern analysis of Lp1-FEHa revealed transcript accumulation in leaf tissues accumulating fructans while transcript level was low in the photosynthetic tissues. The high expression level of this 1-FEH in conditions of active fructan synthesis, together with its low expression level when fructan contents are low, suggest that it might play a role as a β-(2,1) trimming enzyme acting during fructan synthesis in concert with fructan synthesis enzymes.
Sainfoin (Onobrychis viciifolia) is a temperate legume that contains condensed tannins (CT), i.e., polyphenols that are able to bind proteins and thus reduce protein degradation in the rumen. Few ...studies have investigated the relation between plant phenology, CT characteristics and nutritive value of sainfoin. In this study we investigated differences among three sainfoin varieties (Esparcette, Ambra and Villahoz) that were of different geographical origin, and which were cultivated at the same site over the course of two growth cycles and compared with a tannin‐free legume, lucerne (Aubigny). Plants were harvested on nine dates in the first and four dates in the second growth cycle. Phenological stages were analysed for leaf‐to‐whole‐plant ratio, nitrogen (N), organic matter digestibility (OMd) by the pepsin‐cellulase method, cell‐wall concentration, N solubility (solN) plus CT concentration, biological activity and structures. Leaf‐to‐whole‐plant, cell‐wall concentration, N of sainfoin and lucerne were closely related to the phenological stage. Although sainfoin developed earlier than lucerne, its pepsin‐cellulase digestibility was higher than or close to lucerne. Esparcette had the lowest OMd, N and solN and the highest CT concentration. CT concentration, proportion of prodelphinidins (PD) and mean degree of polymerization (mDP) increased with the phenological stage (or plant maturity), and these parameters were associated with lower biological activity of CT. Sainfoin varieties differed in their relationships between phenological stages, nutritional parameters and CT characteristics. The results demonstrated that sainfoin can be a valuable alternative forage legume to lucerne.
À partir d’un échantillon de 1 503 personnes, cette étude s’intéresse aux patients des centres d’assistance médicale à la procréation (AMP) pris en charge en France en 2020 afin d’interroger leur ...parcours médical comme leurs expériences de l’infertilité dans la vie professionnelle, intime, familiale et conjugale. Le questionnaire en ligne, composé de 178 questions, offre trois grandes familles de résultats : les domaines dans lesquels l’AMP donne satisfaction à une majorité de personnes ; les points de vigilance ; les résultats les plus frappants, notamment l’invisibilité des jeunes et des hommes parmi les patients, le pessimisme quant aux résultats de leur traitement et la difficile relation au corps pour les femmes. L’ensemble des résultats souligne l’importance d’une conception globale des patients infertiles, hommes et femmes, jeunes et moins jeunes, au-delà de la seule dimension médicale, pour une prise en compte aussi bien psychologique, sociale que professionnelle, sous-tendue par une équipe d’accompagnants élargie.
When animals are fed a grass and legume mixture, digestive interactions can occur in the rumen between the substrates contained in the different plants, and the response of the animal to the ...combination of forages can differ from the balanced median values of their components considered individually. Our objective was to assess the associative effects between temperate forages in 8 grass-legume binary combinations on in vitro rumen fermentation characteristics to highlight synergies or antagonisms in terms of nutritional and environmental impacts. Two grasses (cocksfoot, CF; ryegrass, RG) and 4 legume species (alfalfa, A; white clover, WC; red clover, RC; sainfoin, SAN) were incubated alone and in grass-legume mixture (1:1, wt/wt) in batches containing buffered rumen fluid during 3.5 and 24 h. For each substrate and each incubation time, parameters describing the degradation of the energetic and nitrogenous compounds and their partition into fermentation end products were measured. Data were subjected to ANOVA using a mixed procedure to test quadratic contrasts. At 3.5 h of incubation, many quadratic effect were observed. The presence of A, WC, or RC in mixtures quadratically increased the NH^sub 3^-N production (up to +28% when compared with the calculated value, P < 0.001), whereas the presence of condensed tannin (CT) activity in SAN considerably decreased it (up to -67%, quadratic effect, P < 0.001) and the N disappearance. To a lesser extent, the presence of SAN reduced the proportion of methane in the gas produced (up to 7%, quadratic effect, P = 0.018). Generally, the degradation of OM and NDF was not stimulated by mixing grass and legume, except for SAN. However, the presence of SAN severely impaired the NDF digestion at the early phase of fermentation. At 24 h of incubation, few associative effects were observed in comparison with those observed at 3.5 h of incubation, but the effect of CT of SAN on N metabolism was still clearly present. This study shows that, among the grass-legume mixtures tested in vitro, only the presence of SAN can interact with the grasses to reduce the degradation of proteins and the production of methane but with a transitory negative effect on fiber digestion. PUBLICATION ABSTRACT
Enterococcus species are associated with an increased morbidity in intraabdominal infections (IAI). However, their impact on mortality remains uncertain. Moreover, the influence on outcome of the ...appropriate or inappropriate status of initial antimicrobial therapy (IAT) is subjected to debate, except in septic shock. The aim of our study was to evaluate whether an IAT that did not cover Enterococcus spp. was associated with 30-day mortality in ICU patients presenting with IAI growing with Enterococcus spp.
Retrospective analysis of French database OutcomeRea from 1997 to 2016. We included all patients with IAI with a peritoneal sample growing with Enterococcus. Primary endpoint was 30-day mortality.
Of the 1017 patients with IAI, 76 (8%) patients were included. Thirty-day mortality in patients with inadequate IAT against Enterococcus was higher (7/18 (39%) vs 10/58 (17%), p = 0.05); however, the incidence of postoperative complications was similar. Presence of Enterococcus spp. other than E. faecalis alone was associated with a significantly higher mortality, even greater when IAT was inadequate. Main risk factors for having an Enterococcus other than E. faecalis alone were as follows: SAPS score on day 0, ICU-acquired IAI, and antimicrobial therapy within 3 months prior to IAI especially with third-generation cephalosporins. Univariate analysis found a higher hazard ratio of death with an Enterococcus other than E. faecalis alone that had an inadequate IAT (HR = 4.4 1.3-15.3, p = 0.019) versus an adequate IAT (HR = 3.1 1.0-10.0, p = 0.053). However, after adjusting for confounders (i.e., SAPS II and septic shock at IAI diagnosis, ICU-acquired peritonitis, and adequacy of IAT for other germs), the impact of the adequacy of IAT was no longer significant in multivariate analysis. Septic shock at diagnosis and ICU-acquired IAI were prognostic factors.
An IAT which does not cover Enterococcus is associated with an increased 30-day mortality in ICU patients presenting with an IAI growing with Enterococcus, especially when it is not an E. faecalis alone. It seems reasonable to use an IAT active against Enterococcus in severe postoperative ICU-acquired IAI, especially when a third-generation cephalosporin has been used within 3 months.
The objective of this paper is to analyze the behaviour of a backscattered signalaccording to soil moisture depth over bare soils. Analysis based on experimental verticalmoisture profiles and ...ASAR/ENVISAT measurements has been carried out. A modifiedIEM model with three permittivity layers (0-1cm, 1-2cm, 2-5cm) has been developed andused in this study. Results show a small effect of moisture profile on the backscatteredsignal (less than 0.5dB). However, measurements and simulations have provided a moredetailed insight into the behaviour of the radar signal and have shown that it was importantto consistently use the same protocol when performing ground truth measurements of soilmoisture.
•A synergism on ruminal digestion is observed when alfalfa is mixed with axonopus.•The condensed tannins of sainfoin allow to reduce ruminal protein degradability.•The condensed tannins of sainfoin ...allow to mitigate methane production.•The condensed tannins content in peanut is not enough to have the same effects.
Associative effects between plants included in some mixtures with tropical and temperate species, which are able to grow in a wide range of temperature, deserve to be better investigated. The aim of this work was to assess the in vitro rumen fermentation characteristics when a tropical (peanut, Arachis pintoi) or temperate legume (sainfoin, Onobrychis viciifolia) with condensed tannins (CT), or a temperate legume without CT (alfalfa, Medicago sativa), were mixed with a tropical (axonopus, Axonopus catharinenses) or a temperate grass (tall fescue, Festuca arundinacea). Different proportions of each legume were mixed with each grass (in%, on dry matter (DM) basis, 0:100, 25:75, 50:50 75:25 and 100:0), and were tested using an in vitro rumen fermentation assay. The crude protein content in both tropical and temperate grasses ranged from 100 to 120g/kg DM, but the aNDF content was much higher in the tropical (617g/kg DM) than in the temperate grass (464g/kg DM). The ADF (+214g/kg DM) and lignin (+46.2g/kg DM) content was much higher in the alfalfa when compared with the average of two other legumes. Positive quadratic effects were detected on in vitro DM disappearance (IVDMD), total gas production, and volatile fatty acids production, when alfalfa was mixed with axonopus, but similar response was not observed when alfalfa was mixed with tall fescue. The IVDMD and total gas production linearly increased when the proportion of peanut or sainfoin increased in the mixtures containing axonopus, but did not change when these legumes were mixed with tall fescue. The ammonia production increased when the proportion of legume increased in all mixtures. Reductions on ammonia and methane (CH4) productions were observed in mixtures containing sainfoin without the presence of polyethylene glycol (PEG) compared to fermentation done with PEG, but this response was not observed in the mixtures containing peanut. We conclude that complementarities in terms of energy and protein content can create favourable conditions leading to positive associative effects on rumen digestive parameters when legume species were mixed with axonopus, but not when they are mixed with tall fescue, probably due to different fibre content of grasses. The CT of sainfoin allow to reduce ruminal protein degradability and mitigate CH4 emissions per kg of DM, while the CT content of peanut is not enough to have the same effects.
•Bioactive legumes and grass produce associative effects on volatile fatty acids.•Bioactive legumes increase protein protection during in vitro rumen fermentation.•Bioactive legumes in grass silage ...did not change dry matter disappearance.•Inclusion of bioactive legumes in grass silage did not affect methane production.
In this study, we tested the effects of the inclusion in silages of bioactive legumes containing condensed tannins (CT) or polyphenol oxidase (PPO), ensiled alone or in mixture with one grass species, on in vitro rumen fermentations. Six mini-silos were prepared in triplicate as follows: pure sainfoin (SF), pure red clover (RC), pure timothy (T, control without bioactive compounds); binary mixtures T–SF and T–RC (in g/kg on a DM basis, 500:500); ternary mixture T–SF–RC (in g/kg on a DM basis, 500:250:250). Samples from each mini-silo were incubated under anaerobic conditions in culture bottles containing buffered rumen fluid from sheep. Rumen fermentation parameters, namely DM disappearance, volatile fatty acids (VFA), ammonia (NH3), gas production and methane (CH4) were determined. The presence of RC in mixtures with T or T–SF results in fermentation similar to pure T and a positive associative effect between T and RC on total VFA production was observed (P=0.029). The NH3: total N ratio was similar among the treatments, but lower values for NH3: insoluble N ratio in silages containing SF or RC (P<0.05, except for T–SF) indicates that the bioactive compounds can limit silage protein degradation in the rumen. The CH4 production per g of DM only tended to differ among treatments (P=0.096), being slightly lower for pure SF than for pure T and RC, probably due to differences in the fermentation pathways towards less acetate and butyrate productions. Overall, the benefits of including RC in forage mixtures previously observed on silage quality are also present on ruminal digestion efficiency.
•Ensiling and sample conditioning have an effect on in situ degradation of maize.•Ensiling maize increased in situ degradability of dry matter and starch.•Ensiling maize decreased in situ ...degradability of cell walls (aNDF).•Grinding dried samples at 4mm limits starch losses during in situ degradation.
High-production ruminants are commonly fed maize silage, which makes accurate evaluation of its nutritive value a key economic issue. However, evaluations of the rate and extent of ruminal degradation of starch and cell wall fractions from maize silage carry uncertainty due to the lack of a standardized method. Here, we investigated the effects of ensiling and sample conditioning on in situ-measured degradation of maize forage. Eight series of maize samples (two hybrids×two maturity stages×two methods of conservation non-ensiled or fresh and ensiled) were nylon-bagged in three conditionings: dried and ground to 1mm (D1), dried and ground to 4mm (D4), frozen and coarse-ground (FG). Disappearance of dry matter (DM), starch and fibre (aNDF) was measured in situ in cow rumen after different incubation times (2, 4, 8, 16, 24, 48 and 96h). Effects of ensiling, sample conditioning, genotype, maturity and their interactions on DM, starch and aNDF degradation were analyzed using the SAS MIXED procedure. Effective dry matter degradability (ED4DM) was significantly higher (P<0.001) in silage than in fresh maize due to a significantly higher rapidly degradable fraction (a) (P<0.001). Effective starch degradability (ED6Starch) followed the same trend due to a higher silage degradation rate (P<0.01). Conversely, effective aNDF degradability (ED2aNDF) was lower in silage (P<0.001) than fresh maize due to the longer lag-time to degradation (P<0.001) and lower hemicellulose ((aNDF−ADF)/aNDF) fraction in silage. Effective DM degradability was higher (P<0.001) for D1 samples than D4 and FG samples, mainly due to the higher rapidly degradable fraction (a) (P<0.001) in D1 than D4 or FG samples. In relation to high degradation rate, starch degradability was significantly higher (P<0.001) in FG than D1 and D4 samples, whereas aNDF degradation was lowest in the FG samples. This study shows that ensiling maize increases starch degradability and decreases aNDF degradability compared to fresh plant. Alongside conservation method, fine-grinding samples (as D1) led to high losses through the pores of the nylon bags, and these losses were correlated with high starch degradability, whereas coarse grinding (as FG) led to low aNDF degradability, probably due to insufficiently reduced particle sizes. In conclusion, using ensiled samples dried and ground to 4mm (D4) emerges as the appropriate method for in situ studies of starch-rich forages used as silages.
The study of carbohydrate metabolism in perennial ryegrass (Lolium perenne L. cv. Bravo) during the first 48 h of regrowth showed that fructans from elongating leaf bases were hydrolysed first ...whereas fructans in mature leaf sheaths were degraded only after a lag of 1.5 h. In elongating leaf bases, the decline in fructan content occurred not only in the differentiation zone (30—60 mm from the leaf base), but also in the growth zone. Unlike other soluble carbohydrates, the net deposition rate of fructose remained positive and even rose during the first day following defoliation. The activity of fructan exohydrolase (FEH; EC 3.2.1.80) was maximal in the differentiation zone before defoliation and increased in all segments, but peaked in the growth zone after defoliation. These data strongly indicate that fructans stored in the leaf growth zone were hydrolysed and recycled in that zone to sustain the refoliation immediately after defoliation. Despite the depletion of carbohydrates, leaves of defoliated plants elongated at a significantly higher rate than those of undefoliated plants, during the first 10 h of regrowth. This can be partly attributed to the transient increase in water and nitrate deposition rate. The results are discussed in relation to defoliation tolerance.
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