Administration of Bacillus subtilis strains in the rearing water enhances the water quality, growth performance, immune response, and resistance against Vibrio harveyi infection in juvenile white shrimp, Litopenaeus vannamei

In this study, vegetative cell suspensions of two Bacillus subtilis strains, L10 and G1 in equal proportions, was administered at two different doses 105 (BM5) and 108 (BM8) CFU ml−1 in the rearing water of shrimp (Litopenaeus vannamei) for eight weeks. Both probiotic groups showed a significant reduction of ammonia, nitrite and nitrate ions under in vitro and in vivo conditions. In comparison to untreated control group, final weight, weight gain, specific growth rate (SGR), food conversion ratio (FCR) and digestive enzymatic activity were significantly greater in the BM5 and BM8 groups. Significant differences for survival were recorded in the BM8 group as compared to the control. Eight weeks after the start of experiment, shrimp were challenged with Vibrio harveyi. Statistical analysis revealed significant differences in shrimp survival between probiotic and control groups. Cumulative mortality of the control group was 80%, whereas cumulative mortality of the shrimp that had been given probiotics was 36.7% with MB8 and 50% with MB5. Subsequently, real-time RT-PCR was employed to determine the mRNA levels of prophenoloxidase (proPO), peroxinectin (PE), lipopolysaccharide- and β-1,3-glucan- binding protein (LGBP) and serine protein (SP). The expression of all immune-related genes studied was only significantly up-regulated in the BM5 group compared to the BM8 and control groups. These results suggest that administration of B. subtilis strains in the rearing water confers beneficial effects for shrimp aquaculture, considering water quality, growth performance, digestive enzymatic activity, immune response and disease resistance

Capturing Ecosystem Services, Stakeholders' Preferences and Trade-Offs in Coastal Aquaculture Decisions : A Bayesian Belief Network Application

Aquaculture activities are embedded in complex social-ecological systems. However, aquaculture development decisions have tended to be driven by revenue generation, failing to account for interactions with the environment and the full value of the benefits derived from services provided by local ecosystems. Trade-offs resulting from changes in ecosystem services provision and associated impacts on livelihoods are also often overlooked. This paper proposes an innovative application of Bayesian belief networks - influence diagrams - as a decision support system for mediating trade-offs arising from the development of shrimp aquaculture in Thailand. Senior experts were consulted (n = 12) and primary farm data on the economics of shrimp farming (n = 20) were collected alongside secondary information on ecosystem services, in order to construct and populate the network. Trade-offs were quantitatively assessed through the generation of a probabilistic impact matrix. This matrix captures nonlinearity and uncertainty and describes the relative performance and impacts of shrimp farming management scenarios on local livelihoods. It also incorporates export revenues and provision and value of ecosystem services such as coastal protection and biodiversity. This research shows that Bayesian belief modeling can support complex decision-making on pathways for sustainable coastal aquaculture development and thus contributes to the debate on the role of aquaculture in social-ecological resilience and economic development

Transfer of DNA between bacteria via phages.

<p>A temperate phage inserts its genome (red) into the bacterial chromosome (blue-green) as a prophage, which replicates along with the bacterial chromosome, packaging host DNA alone (generalized transduction) or with its own DNA (specialized transduction). It then lyses the bacterial cell, releasing progeny phage particles into the surrounding environment. After lysis, these phages infect new bacterial cells, in which the acquired DNA recombines with the recipient cell chromosome (orange). This figure has been adapted from Frost et al. <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1004219#ppat.1004219-Frost1" target="_blank">[2]</a>.</p

Metagenomic exploration of the resistome from human and environmental sources.

<p>Relative distribution of reads assigned to three functional subsystems among 27 metagenomes (based on MG-RAST annotation, <i>E</i>-value  =  10⁻⁵). Data are normalized by the total annotated sequences and are expressed as a percentage. The horizontal line in each box plot represents the mean of the relative distribution in each of the five environments (oceans, soils, freshwater, human feces, and WWTPs). The 27 metagenomes used for the analysis are available at <a href="http://metagenomics.anl.gov" target="_blank">http://metagenomics.anl.gov</a><a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1004219#ppat.1004219-Meyer1" target="_blank">[13]</a>. Accession numbers for oceans: 4441573.3, 4441574.3, 4441576.3, 4441577.3, 4441591.3, and 4443729.3; soils: 4441091.3, 4445990.3, 4445993.3, 4445994.3, 4445996.3, and 4446153.3; freshwater (rivers): 4511251.3, 4511252.3, 4511254.3, 4511255.3, 4511256.3, and 4511257.3; human feces: 4440595.4, 4440460.5, 4440611.3, 4440614.3, 4440825.3, and 4461119.3; and WWTPs: 4455295.3, 4463936.3, and 4467420.3.</p

Relative concentration of ARGs in biofilm and sediment samples.

<p>Within the box plot chart, the crosspieces of each box plot represent (from top to bottom) maximum, upper-quartile, median (black bar), lower-quartile, and minimum values. An asterisk (*) denotes a statistically significant difference between upstream and downstream sites (<i>P</i><0.05).</p

The dendrograms represent the similarity among the samples based on the Bray-Curtis coefficient.

<p>Scale bars indicate the similarity obtained from calculated matrices.</p

Graphene oxide addition to anaerobic digestion of waste activated sludge: Impact on methane production and removal of emerging contaminants

8 Páginas.-- 4 Figuras.-- 3 TablasThe effect of graphene oxide on the anaerobic digestion of waste activated sludge was investigated at two graphene oxide concentrations (0.025 and 0.075 g graphene oxide per g volatile solids) using biochemical methane potential tests. The occurrence of 36 pharmaceuticals was monitored in the solid and liquid phases before and after the anaerobic treatment. The addition of graphene oxide improved the removal of most pharmaceuticals detected, even those that are considered persistent to biological degradation, such as azithromycin, carbamazepine, and diclofenac. No significant differences were observed in the final specific methane production without graphene oxide and with the lowest graphene oxide concentration, yet the highest graphene oxide concentration partially inhibited methane production. The relative abundance of antibiotic resistance genes was not affected by the graphene oxide addition. Finally, significant changes in the microbial community including bacteria and archaea were detected with graphene oxide addition.This research is funded by AEI (Agencia Estatal de Investigación, Spanish Government) through project ANTARES (PID 2019-110346RB-C22). O. Casabella acknowledges funding from the Secretariat of Universities and Research from Generalitat de Catalunya and the European Social Fund for his FI fellowship (2022 FI_B1 00122). M. Gros acknowledges her Ramon y Cajal contract (RYC 2020-030324-I) funded by the MCIN/AEI 10.13039/501100011033 and by “ESF Investing in your future”. The authors acknowledge the support from the Economy and Knowledge Department of the Catalan Government through a Consolidated Research Group (ICRA-TECH - 2021 SGR 01283) and (SGR ICRA-ENV 2021 01282).Peer reviewe