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Phytochemical Composition, Antioxidant, and Antimicrobial Attributes of Different Solvent Extracts from Myrica esculenta Buch.-Ham. ex. D. Don Leaves
No full textBackground: Plant diversity is a basic source of food and medicine for local Himalayan communities. The current study was designed to assess the effect of different solvents (methanol, ethyl acetate, and water) on the phenolic profile, and the corresponding biological activity was studied. Methods: Antioxidant activity was investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2″-azino-bis(3-ethylbenzothiazoline-6-sulphonic) acid (ABTS) assay, while the antimicrobial activity was evaluated by disk diffusion method using various bacterial and fungal strains. Results: The outcomes demonstrated that methanol acted as the most effective solvent for polyphenols extraction, as strengthened by the liquid chromatography and mass spectroscopy (LC-MS) and fourier transform infrared spectroscopy (FTIR) analysis. M. esculenta methanol extract showed the highest DPPH and ABTS radical scavenger antioxidant activity with IC50 values of 39.29 μg/mL and 52.83 μg/mL, respectively, while the ethyl acetate and aqueous extracts revealed minimum antioxidant potential. Methanol extract also revealed higher phenolic content, 88.94 ± 0.24 mg of equivalent gallic acid (GAE)/g), measured by the Folin–Ciocalteu method, while the minimum content was recorded for aqueous extract (62.38 ± 0.14 GAE/g). The highest flavonoid content was observed for methanol extract, 67.44 ± 0.14 mg quercetin equivalent (QE)/g) measured by an aluminum chloride colorimetric method, while the lowest content was recorded for aqueous extract (35.77 ± 0.14 QE/g). Antimicrobial activity findings also reveal that the methanol extract led to a higher inhibition zone against bacterial and fungal strains. FTIR analysis reveals the presence of various functional groups, viz. alkenes, amines, carboxylic acids, amides, esters, alcohols, phenols, ketones, carboxylic acids, and aromatic compounds. This FTIR analysis could serve as a basis for the authentication of M. esculenta extracts for future industrial applications. Compounds identified by LC-MS analysis were gallic acid, myricanol, myricanone, epigallocatechin 3-O-gallate, β-sitosterol, quercetin, p-coumaric acid, palmitic acid, n-pentadecanol, n-octadecanol, stigmasterol, oleanolic acid, n-hexadecanol, cis-β-caryophyllene, lupeol, and myresculoside. Conclusion: This study suggests that the methanolic extract from M. esculenta leaves has strong antioxidant potential and could be a significant source of natural antioxidants and antimicrobials for functional foods formulation
Potential of precision livestock farming in small ruminant farming systems
No full textTae benefit of precision livestock fanning (PLF) is well recognised in the more intensive livestock sec.tors, such
as dairy, pig and poultry. However, PLF has not been applied as \videly in species where animals are con5idered to have a lower individual value or with Jess ec.onomic interest, as is the case in small ruminants (SR), or in extensive management systems. This is despite the very significant production, welfare, and labour efficiency advantages that can be achieved by applying PLF in these contexts. Despite their crucial role for the rural economy, society, and environment and their importance in ecosystem services such as biodiversity and maintaining cultural heritage, SR systems face issues such as challenging clinlatic and topographie.al conditions, Jack of labour and low profitability that could be alleviated by introducing PLF technologies. Research on PLF for systems bas been recently emerging, but perhaps Jacks a joint up approach. Tiris paper present an overview of current research and potential for future applications in several countries of PLF for SR system5 on varions themes, highlighting the wealth of potentially available solutions and prototypes. The topics presented cover feed and water intake, health, disease and parasite control and mo1ritoring, fertility and reproduction management, grazing and predation control, animal locations and management monitoring, lambing and mismothering issues, as well as lactation monitoring. Issues relating to acceptability, economic relevance, technology readiness level (TRL) and industry engagement will also be discussed
Genetic correlations among selected traits in Canadian Holsteins
No full textIn the Canadian dairy industry, there are currently over 80 traits routinely evaluated, and more areconsidered for potential selection. Particularly, in the last few years, recording has commenced for several newphenotypes required to introduce novel traits with high economic importance into the selection program.However, without a systematic estimation of the genetic correlations that exist among traits, the potential resultsof indirect selection are unknown. Therefore, 29 traits representative of the trait diversity for first lactationCanadian animals were selected. Their two-by-two genetic correlations were estimated from a dataset of 62 498first lactation Holstein cows, using a Markov Chain Monte Carlo Gibbs sampling approach. The general tendenciesamong the groups of traits confirm that production traits are negatively correlated with fertility traits and thatfunctional traits are positively correlated with one another. The association of udder depth with fertility anddisease resistance has also been highlighted. This contribution offers a comprehensive overview of current esti-mates across traits and includes correlations with novel traits that constitute an original addition to the literature.These new estimates can be used for newly developed genomic evaluation models and possibly lead to more accu-rate estimations of the dairy cows’overall genetic merit
Genome Sequences of 17 Pasteurella multocida Strains Involved in Cases of Rabbit Pasteurellosis
No full textThis article reports draft genome sequences of 17 Pasteurella multocida strains isolated from naturally infected rabbits. The total lengths of the assembled contigs ranged between 2.21 and 2.48 Mb, and the total number of genes detected on the contigs ranged between 2,088 and 2,416
PGE2 concentration of the follicular fluid as a measure of heterogeneity of the response to hormonal stimulation of the bovine ovarian follicle
No full textThe LH surge promotes prostaglandin E2 (PGE2) production within the preovulatory follicle. Oocyte
microenvironment levels of PGE2 affect the developmental competence after fertilization. This study
aimed to characterize the follicular fluid PGE2 enrichment during superovulation treatment. Six heifers
(Holstein, 20.3 +/-0.85 months old) received FSH (Stimufol®, Reprobiol, Belgium): half dose, ie, 250 μg
of porcine follitropin (pFSH), combined with 50 μg of porcine lutropin (pLH). At the rate of 8 injections,
in degressive dose, spread over 4 days. PGF2α (Estrumate®, MSD Santé Animale, France) was injected
at the same time as the 5th injection of Stimufol®.LH peak was assumed to occur between 35 and 40
hours after the PGF2α injection. Individual sampling of fluid from antral follicles was performed by
ovum pick up 12 hours before PGF2α injection and 60 hours after PGF2α injection. This protocol was
designed to allow the collection of fluids from ovarian follicle containing either a pre-matured or a
matured oocyte. Each heifer was his own control as we took the "pre-matured" follicular fluid on a first
ovary and the "matured" follicular fluid on the 2nd ovary, 3 days later. The punctures were repeated
twice and were cross-checked for the next repetition to evaluate the impact of the ipsi or contralateral
side of the corpus luteum (CL) on the follicular fluid composition. The volume of fluid was measured for
each punctured follicle. The PGE2 concentration of the follicular fluid was measured by Elisa (Cayman
Chemical) to determine the progress of terminal follicular differentiation. An average of 13 +/- 5.06 and
28 +/-13.9 follicles were punctured per session/heifer for respectively pre-matured (n=78) and matured
(n=169) follicles. The mean collected volume differed between the two groups (pre-matured: 0.229+/-
0.213 ml/follicle; matured: 0.575+/-0.379 ml/follicle; two samples t-test, pval<0.0001). No effect of the
side of CL on fluid volume was detected (2-way Anova, p=0.397). The PGE2 concentration was
determined in 25 pre-matured follicles and 127 matured follicles. The mean PGE2 concentration
significantly differed between the two groups of follicular fluids (pre-matured: 7.2 +/-7.5 ng/ml; matured:
60.2 +/-58.6 ng/ml) No effect of the side of CL was detected (p=0.278). Surprisingly, there was no linear
relationship between fluid volume and PGE2 concentration (adjusted R-squared: -0.0002, pvalue=0.327). PGE2 concentrations were very spread out within the matured group. This important
dispersion (Interquartile range=58.6 ng/ml) indicated that despite follicle growth in response to hormonal
stimulation (FSH/LH) the ability of follicular granulosa and cumulus cells to synthesize PGE2 was
imperfectly achieved. Only 48% of the follicular fluids in the mature group had higher PGE2 levels than
those in the premature follicle group. In conclusion, despite the ability of the stimulation treatment to
promote growth of many follicles, there was a great heterogeneity in terms of PGE2 synthesis. This
alteration could represent defective signaling mechanisms that could impact the developmental
competence of the oocyte
État des lieux des associations environnementalistes en Guadeloupe : une proposition de travail en réseau pour améliorer leur performance
No full textLa Guadeloupe est actuellement confrontée à de nombreux dérèglements environnementaux d'origine naturelle et anthropique. Les associations environnementalistes jouent un rôle essentiel dans la protection de la nature, l'amélioration du cadre de vie et la sensibilisation de la population, mais elles sont soumises à des contraintes qui entravent leurs activités. Dans ce contexte, l'objectif de cette étude a été, d'une part, de réaliser un diagnostic de la structure et du fonctionnement de ces associations et, d'autre part, de proposer des éléments factuels en vue d'améliorer leur efficacité et leur visibilité dans la société de Guadeloupe.
Le diagnostic a été basé sur l'analyse de la liste des 121 associations environnementalistes fournie par la Direction de l’Équipement, de l'Aménagement et du Logement ( DEAL Guadeloupe), la recherche sur Internet des sites Web des associations, et la réalisation des enquêtes sur un échantillon de 28 associations, sélectionnées par leur objet (analyse typologique) et par l'information obtenue sur les sites Web. Nous nous sommes fondé sur ce diagnostic afin de proposer la construction d'un réseau "possible", incluant quelques-unes des associations enquêtées, en détaillant les aspects jugés clés de son organisation.
Nous avons constaté que la taille des associations (nombre d'adhérents) est un bon indicateur de leur structure et leur fonctionnement. Elle détermine leur objet, leur niveau de professionnalisation (technicité), le type et le nombre de difficultés retrouvées. Les petites et moyennes associations (<25 adhérents) constituent le groupe associatif présentant le moins de technicité et, en conséquence, elles font face à des difficultés plus diverses et nombreuses que les grandes associations (ressources humaines et financières, communication, organisation interne). L'analyse de ces difficultés nous a permis d'établir des indicateurs qualitatifs de technicité qui nous ont aidés à identifier les priorités d'amélioration.
Les résultats du diagnostic nous ont amené à proposer la construction de réseaux d'associations afin de pallier les difficultés observées et d'apporter de la valeur ajoutée aux activités associatives. Notre démarche a ciblé les petites et moyennes associations. Nous avons proposé et analysé un cas concret de réseau s'articulant autour de la réhabilitation de mares en Guadeloupe, comportant quatre domaines d'intervention : technique, éducation à l'environnement, insertion des jeunes et communication. Pour cela, nous avons élaboré un Plan stratégique sur lequel s'appuie la structuration du réseau et la formalisation du Projet associatif, en détaillant en particulier le Plan de communication, l'Ingénierie de recherche de financement et la Gestion des ressources humaines
Behavioral genetics of the interactions between Apis mellifera and Varroa destructor
No full textThe western honeybee Apis mellifera exhibits a diverse set of adaptations in response to infestations by its most virulent disease-causing agent, the ectoparasitic mite Varroa destructor. In this study, we investigated the effect of honeybee pupae genotype on the expression of four host and parasite traits that are associated with the reproductive phase of the mite in the brood of its host. We first phenotyped cells containing bee pupae to assess their infestation status, their infestation level, the reproductive status of the mites, and the recapping of cells by adult workers. We then genotyped individual pupae with five microsatellites markers to compare these phenotypes across full sister groups. We found that the four phenotypes varied significantly in time but did not across the subfamilies within the colonies. These findings show that V. destructor mites do not differentially infest or reproduce on some particular honeybee patrilines, and that workers do not target preferentially specific pupae genotypes when performing recapping. These findings bring new insights that can help designing sustainable mite control strategies through breeding and provide new insights into the interactions between A. mellifera and V. destructor
Sex‐specific selection on plant architecture through “budget” and “direct” effects in experimental populations of the wind‐pollinated herb, Mercurialis annua
No full textSexual selection may contribute to the evolution of plant sexual dimorphism by favoring architectural traits in males that improve pollen dispersal to mates. In both sexes, larger individuals may be favored by allowing the allocation of more resources to gamete production (a ‘budget’ effect of size). In wind‐pollinated plants, large size may also benefit males by allowing the liberation pollen from a greater height, fostering its dispersal (a ‘direct’ effect of size). To assess these effects and their implications for trait selection, we measured selection on plant morphology in both males and females of the wind‐pollinated dioecious herb Mercurialis annua in two separate experimental common gardens at contrasting density. In both gardens, selection strongly favored males that disperse their pollen further. Selection for pollen production was observed in the high‐density garden only and was weak. In addition, male morphologies associated with increased mean pollen dispersal differed between the two gardens, as elongated branches were favored in the high‐density garden while shorter plants with longer inflorescence stalks were favored in the low‐density garden. Larger females were selected in both gardens. Our results point to the importance of both a direct effect of selection on male traits that affect pollen dispersal, and, to a lesser extent, a budget effect of selection on pollen production
Biofilm formation and synthesis of antimicrobial compounds by the biocontrol agent Bacillus velezensis QST713 in an Agaricus bisporus compost micromodel
No full textBacillus velezensis QST713 is widely used as a biological control agent for crop protection and disease suppression. This strain is used industrially in France for the protection of Agaricus bisporus against Trichoderma aggressivum f. europaeum, the green mould disease. The efficacy of this biocontrol process had been evaluated in a previous report, yet the mode of its action has not been explored under production conditions. In order to decipher the underlying biocontrol mechanisms for effective biofilm formation of strain QST713 in the compost and for the involvement of antimicrobial compounds, we developed a simplified micromodel for the culture of A. bisporus during its early culture cycle. By using this micromodel system, we studied the transcriptional response of strain QST713 in the presence or absence of A. bisporus and/or T. aggressivum in axenic industrial compost. We report an over-expression of several genes of the biocontrol agent involved in biofilm formation in the compost compared to expression during growth in broth compost extract, either in the exponential growth phase (epsC, blsA and tapA genes) or in the stationary growth phase (tapA gene), while a gene encoding a flagellar protein (hag) was under-expressed. We also report an over-expression of Bacillus velezensis QST713 genes related to surfactin (srfAA) and fengycin (fenA) production in the presence of the fungal pathogen in the compost.ImportanceBiocontrol agents are increasingly used to replace chemical pesticides to prevent crop diseases. In the button mushroom field in France, the use of Bacillus velezensis QST713 as a biocontrol agent against the green mold Trichoderma aggressivum, has been shown to be efficient. However, the biocontrol mechanisms effective in the pathosystem Agaricus bisporus/Trichoderma aggressivum/Bacillus velezensis QST713 are still unknown. Our paper focuses on the exploration of the bioprotection mechanisms of the biocontrol agent Bacillus velezensis QST713 during the culture of the button mushroom (Agaricus bisporus) in a micromodel culture system to study the specific response of strain QST713 in the presence of T. aggressivum and/or A. bisporus