Dietary supplementation of black soldier fly (Hermetica illucens) meal modulates gut microbiota, innate immune response and health status of marron (Cherax cainii, Austin 2002) fed poultry-by-product and fishmeal based diets

The present study aimed to evaluate the dietary supplementary effects of black soldier fly (Hermetia illucens) (BSF) meal on the bacterial communities in the distal gut, immune response and growth of freshwater crayfish, marron (Cherax cainii) fed poultry-by-product meal (PBM) as an alternative protein source to fish meal (FM). A total of 64 marron were randomly distributed into 16 different tanks with a density of four marron per tank. After acclimation, a 60-days feeding trial was conducted on marron fed isonitrogenouts and isocalorific diets containing protein source from FM, PBM, and a combination of FM + BSF and PBM + BSF. At the end of the trial, weight gain and growth of marron were found independent of any dietary treatment, however, the two diets supplemented with BSF significantly (P < 0.05) enhanced haemolymph osmolality, lysozyme activity, total haemocyte counts, and protein and energy contents in the tail muscle. In addition, the analysis of microbiota and its predicted metabolic pathways via 16s rRNA revealed a significantly (P < 0.05) higher bacterial activity and gene function correlated to biosynthesis of protein, energy and secondary metabolites in PBM + BSF than other dietary groups. Diets FM + BSF and PBM + BSF were seen to be associated with an up-regulation of cytokine genes in the intestinal tissue of marron. Overall, PBM + BSF diet proved to be a superior diet in terms of improved health status, gut microbiota and up-regulated expression of cytokine genes for marron culture

Characterization and role of the selected microbiome in water remediation and gut health of aquacultured marron (Cherax cainii, Austin 2002)

Seven trials were conducted under laboratory conditions to characterize the gut and rearing water microbiota of marron when exposed to various substrates and fed selected probiotics and non-fishmeal protein sources. The results showed that Lactobacillus spp., and substrate Water Cleanser significantly improved the gut microbial diversity and immune-competence of marron. Non-fishmeal protein ingredients including poultry-by-product and black soldier fly meal have an ability to replace fishmeal protein from marron diet without any detrimental effects

Lactobacillus acidophilus and L. plantarum improve health status, modulate gut microbiota and innate immune response of marron (Cherax cainii).

This study aimed to investigate the combined effects of two most potent probiotic bacteria Lactobacillus acidophilus and Lactobacillus plantarum on overall health and immune status of freshwater crayfish, marron under laboratory conditions. A total of 36 marron were distributed into six different tanks and two different feeding groups, control and probiotic-fed group. After acclimation, control group was fed with basal diet while probiotic group was fed 109 CFU/mL per kg of bacterial supplemented feed for 60 days. The results showed no significant differences in weight gain, however, probiotic feed significantly enhanced some hemolymph parameters and biochemical composition of tail muscle. Histology data revealed better hepatopancreas health and higher microvilli counts in the marron gut fed probiotic diet. The probiotic bacteria triggered significant shift of microbial communities at different taxa level, mostly those reported as beneficial for crayfish. The probiotic diet also enriched the metabolic functions and genes associated with innate immune response of crayfish. Further correlation analysis revealed significant association of some taxa with increased activity for hemolymph and immune genes. Therefore, dietary Lactobacillus supplementation can modulate the overall health and immunity as well as gut microbial composition and interaction network between gut microbiota and immune system in crayfish

Improving the efficiency of DNA extraction from iron incrustations and oilfield-produced water

Abstract The quantity and quality of DNA isolated from environmental samples are crucial for getting robust high-throughput sequencing data commonly used for microbial community analysis. The differences in the nature and physicochemical properties of environmental samples impact DNA yields, and therefore, an optimisation of the protocols is always recommended. For instance, samples collected from corroded areas contain high concentrations of metals, salts, and hydrocarbons that can interfere with several steps of the DNA extraction protocols, thereby reducing yield and quality. In this study, we compared the efficiency of commercially available DNA extraction kits and laboratory-adopted methods for microbial community analysis of iron incrustations and oilfield-produced water samples. Modifications to the kits manufacturers’ protocols were included to maximise the yield and quality. For iron incrustations, the modified protocol for FastDNA Spin Kit for Soil yielded higher DNA and resulted in higher diversity, including the recovery of low-abundant and rare taxa in the samples, compared to DNeasy PowerSoil Pro Kit. The DNA extracted with modified phenol–chloroform methods yielded higher DNA but failed to pass quality control PCR for 16S sequencing with and without purification. The protocols mentioned here can be used to maximise DNA recovery from iron incrustations and oilfield-produced water samples

A Mixture of Manganese, Silica and Phosphorus Supplementation Alters the Plankton Density, Species Diversity, Gut Microbiota and Improved the Health Status of Cultured Marron (Cherax cainii, Austin and Ryan, 2002)

Trace element supplementation to the freshwater environment can influence the plankton density and species diversity, contributing to the nutrition of aquaculture species, especially during the juvenile stage. An experiment was conducted under laboratory conditions to evaluate the effects of supplementing different mixtures of manganese, silica and phosphorus on the plankton density and species diversity and their impact on cultured juvenile marron (Cherax cainii, Austin and Ryan, 2002). Manganese, silica and phosphorus in concentrations of 0.0024, 0.41, 0.05 mg*L ; 0.0041, 0.82, 0.12 mg*L ; and 0.0058, 1.26, 0.25 mg*L respectively termed as low, medium and high were supplemented to tank water containing a phytoplankton density of 3.77 ± 0.16 × 10 cells*L and 292.9 ± 17.6 individuals*L of zooplankton, and plankton growth was observed every 24 h for 6 days. Afterwards, a 3-month trial was conducted studying the effects of these trace element concentrations and resulting plankton densities on marron growth, survival, moulting, gut microbiota and health indices. Silica supplementation at high concentration increased the diatom abundance, silica and phosphorus supplementation at higher concentration that resulted in a significant increase in plankton density and species diversity, leading to improved marron health indices than the control and the tanks receiving a low concentration. Marron-specific growth rate, weight gain and dissolved copper concentration in haemolymph were significantly higher in tanks with higher supplementation and higher plankton density. Marron survival, moult interval and total haemocyte count were not affected by the supplementation. Marron gut microbiota at higher trace element concentration supplementation showed a significant increase in abundance of phosphate solubilizing bacteria

Targeting of Virulence Factors and Plasmid Profiling of Klebsiella pneumoniae Causing Urinary Tract Infection in Sylhet City of Bangladesh

ABSTRACT Studies were conducted to characterize Klebsiella pneumoniae isolates from urinary tract infection (UTI) patients in Sylhet city of Bangladesh. At the same time, all isolates were screened for some common virulence genes and four significant isolates were searched for plasmid number and sizes by mini alkaline-lysis method. Among five tested isolates from female UTI patients, gyrase subunit B2 (gyrb2) amplified in all isolates, lipase and nuclease detected in three isolates and serine protease amplifies in two isolates and gave the expected band of 1130 bp, 517 bp, 1055 bp and 211 bp respectively. Two of four isolates showed 9.82 kb plasmid band on agarose gel. Isolates bearing 9.82 kb plasmid were found to be resistant to multiple commercial antibiotics. At the same time all isolates were screened for in-vitro plate assay for proteolytic, lypolytic and hemolytic activity. Isolates with positive plasmid and more than one virulent gene with gyrB2 showed positive result in in-vitro culture plate with clear zone of proteolysis, hemolysis or lipolysis. This study will be helpful for further study in finding correlation or pattern of virulence properties for K. pneumoniae associated UTI in Bangladesh

Molecular detection and PCR-RFLP analysis using Pst1 and Alu1 of multidrug resistant Klebsiella pneumoniae causing urinary tract infection in women in the eastern part of Bangladesh

Klebsiella pneumoniae is the second leading causative agent of UTI. In this study, a rapid combined polymerase chain reaction and restriction fragment length polymorphism analysis was developed to identify K. pneumoniae in women, infected with urinary tract infection in the Sylhet city of Bangladesh. Analysis of 11 isolates from women at the age range of 20–55 from three different hospitals were done firstly by amplification with K. pneumoniae specific ITS primers. All of the 11 collected isolates were amplified in PCR and showed the expected 136 bp products. Then, restriction fragment length polymorphism analysis of 11 isolates were conducted after PCR amplification by 16s rRNA universal primers, followed by subsequent digestion and incubation with two restriction enzymes, Pst1 and Alu1. Seven out of 11 isolates were digested by Pst1 restriction enzymes, six isolates digested by Alu1, and while others were negative for both enzymes. Data results reveal that, women at age between 25 and 50 were digested by both enzymes. A woman aged over than 50 was negative while bellow 20 was digested by only Pst1. The results could pave the tactic for further research in the detection of K. pneumoniae from UTI infected women. Keywords: Klebsiella pneumoniae, ITS-primer, MDR isolates, PCR-RFLP analysi

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Not AvailableMicroRNAs (miRNAs) are small non-coding RNAs that control the expression ofgenes by targeting specific mRNAs. Data related to miRNAs are limited for fishspecies, with only 16 out of the 30 000 fish species enlisted in miRBase. In the pre-sent review, we have summarized the recent findings on the implication of miR-NAs in the teleost reproduction with an emphasis on commercially importantcandidates. The information related to various miRNAs and their roles duringdifferent developmental stages of gonads in nine important species has been com-piled. We have focused on the trend of sexual dimorphism in the gonadal miRNArepertoire of teleost species. Species-specific variability is observed in the expres-sion pattern of gonadal miRNAs in both male and female fish. It is noteworthythat our summarization of teleost miRNAs in reproduction has highlighted thegaps in functional information on the identified miRNAs (both conserved andnovel). It is only after functional validation of the miRNA targets, one can usethese findings to enhance reproductive health and production of the commercialteleost species to boost overall aquaculture sector.Not Availabl

Marked variations in gut microbiota and some innate immune responses of fresh water crayfish, marron (Cherax cainii, Austin 2002) fed dietary supplementation of Clostridium butyricum

This study aimed to investigate the effects of Clostridium butyricum as a dietary probiotic supplement in fishmeal based diet on growth, gut microbiota and immune performance of marron (Cherax cainii). Marron were randomly distributed into two different treatment groups, control and probiotic fed group. After 42 days of feeding trial, the results revealed a significant (P < 0.05) increase in growth due to increase in number of moults in marron fed probiotics. The probiotic diet also significantly enhanced the total haemocyte counts (THC), lysozyme activity in the haemolymph and protein content of the tail muscle in marron. Compared to control, the 16S rRNA sequences data demonstrated an enrichment of bacterial diversity in the probiotic fed marron where significant increase of Clostridium abundance was observed. The abundance for crayfish pathogen Vibrio and Aeromonas were found to be significantly reduced post feeding with probiotic diet. Predicted metabolic pathway revealed an increased activity for the metabolism and absorption of carbohydrate, degradation of amino acid, fatty acid and toxic compounds, and biosynthesis of secondary metabolites. C. butyricum supplementation also significantly modulated the expression level of immune-responsive genes of marron post challenged with Vibrio mimicus. The overall results suggest that C. butyricum could be used as dietary probiotic supplement in marron aquaculture

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The research was supported by the Institutional Fund (Project code-IXX12206) of ICAR-Indian Institute of Agricultural Biotechnology, Ranchi. Authors are indebted to the staff of the school of molecular diagnostics and prophylactics of IIAB for their research cooperation and technical assistance.An experiment was conducted to study the effect of microbial levan supplemented diet on innate and adaptive immune responses as well as stress biomarkers of pathogen challenged Labeo rohita fingerlings. Fish were randomly divided into two groups in triplicates and fed with a pre-standardized dose of 1.25% (w/w%) levan and without levan (control group) for 60 days. Post completion of the feeding trial, fish from both treatment groups were challenged with a pathogenic strain of A. hydrophila and samples were collected on different time points fill 96 h. The results of the study showed that supplementation of microbial levan significantly upregulated the mRNA levels of TLR22, beta-2 M and IFN-gamma, and downregulated TGF-beta in the intestine, gill, kidney and liver in a time-dependent manner. Significant decrease in the expression of TGF-beta in the hepatic cells was noticed at later time points of 24, 48 and 96 h post-challenge with the highest of 2.66 fold at 48 h. Upregulation of the beta-2 M gene at 48 h and 96 h was noticed in the intestine, gill, liver and kidney. Maximum expression of IFN-gamma was observed at highest time points of 96 h in both intestine and gill, whereas 3.4-fold in the liver at 6 h and 2.6-fold in the kidney at 24 h was noticed. TGF-beta expression analysis displayed the significant downregulation with a maximum decrease of 2.6 fold in the gill at 12 h, while a 2.3-fold and 2.5-fold decrease were noticed at 48 h in the kidney and liver, respectively. Total immunoglobulin level and myeloperoxidase content of A. hydrophila infected rohu increased upto 24 h in the levan-fed group compared to the control. Remarkable decrease of stress biomarkers such as serum cortisol, blood glucose, and HSP70 in the liver, muscle and gill, was observed due to dietary feeding of levan at 24 h. In totality, the present study revealed the significant upregulation of immune responsive genes (TLR22, beta-2 M and IFN-gamma), downregulation of regulatory gene (TGF-beta) and decrease of HSP70, cortisol and blood glucose with dietary microbial levan supplementaion in infected Labeo rohita fingerlings. These findings on the modulation of immune responsive gene and stress parameters provide an understanding about the molecular basis of the function of prospective prebiotic, microbial levan.ICAR-Indian Institute of Agricultural Biotechnology, Ranchi [IXX12206