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IntroductionDeep investigations of host-associated microbiota can illuminate microbe-based solutions to improve production in an unprecedented manner. The poor larval survival represents the critical bottleneck in sustainable marine aquaculture practices. However, little is known about the microbiota profiles and their governing eco-evolutionary processes of the early life stages of marine teleost, impeding the development of suitable beneficial microbial management strategies. The study provides first-hand mechanistic insights into microbiota and its governing eco-evolutionary processes in early life stages of a tropical marine teleost model, Trachinotus blochii.MethodsThe microbiota profiles and their dynamics from the first day of hatching till the end of metamorphosis and that of fingerling’s gut during the routine hatchery production were studied using 16S rRNA amplicon-based high-throughput sequencing. Further, the relative contributions of various external factors (rearing water, live feed, microalgae, and formulated feed) to the microbiota profiles at different ontogenies was also analyzed.ResultsA less diverse but abundant core microbial community (~58% and 54% in the whole microbiota and gut microbiota, respectively) was observed throughout the early life stages, supporting ‘core microbiota’ hypothesis. Surprisingly, there were two well-differentiated clusters in the whole microbiota profiles, ≤10 DPH (days post-hatching) and > 10 DPH samples. The levels of microbial taxonomic signatures of stress indicated increased stress in the early stages, a possible explanation for increased mortality during early life stages. Further, the results suggested an adaptive mechanism for establishing beneficial strains along the ontogenetic progression. Moreover, the highly transient microbiota in the early life stages became stable along the ontogenetic progression, hypothesizing that the earlier life stages will be the best window to influence the microbiota. The egg microbiota also crucially affected the microbial community. Noteworthily, both water and the feed microbiota significantly contributed to the early microbiota, with the feed microbiota having a more significant contribution to fish microbiota. The results illustrated that rotifer enrichment would be the optimal medium for the early larval microbiota manipulations.ConclusionThe present study highlighted the crucial foundations for the microbial ecology of T. blochii during early life stages with implications to develop suitable beneficial microbial management strategies for sustainable mariculture production.

Staphylococcus aureus is the most frequently isolated pathogen from bovine mastitis including subclinical, clinical, and chronic infections. Virulence factors possessed by S. aureus aid in causing infection and inflammation by producing toxins and proteins, which are responsible for the pathogenesis of the disease. In the current study out of 51 animals presented with clinical mastitis, S. aureus was isolated from the milk of 18 animals. S. aureus was confirmed by genus and species level identification using polymerase chain reaction. Molecular characterization of selected virulence genes including thermonuclease (nuc) and Panton Valentine Leucocidin (PVL) was performed in all the S. aureus isolates. Presence of nuc gene was observed in all the isolates (100 %) of S. aureus. No isolates were found to be positive for the presence of PVL gene. Profiling the virulence genes is an important tool for epidemiological studies of mastitis, which can be employed for the prevention and control of the disease.

The marine ornamental fish trading industry is an ever-expanding one, as indicated by its bolstering statistics, which amount to about US$ 300 million. Although the trade is booming, the natural habitats that foster these fishes, such as coral reefs, are steadily declining. One of the reasons for this is the overdependency of the industry on wild-caught fishes. To surpass this, the Central Marine Fisheries Research Institute (CMFRI) has developed hatchery technology for breeding marine ornamental fishes such as seahorses, clownfishes, damsels, and serranids. It began with the breeding of Hippocampus kuda. This progressed to breeding clownfishes such as Amphiprion chrysogaster, A. ocellaris, A. nigripes, A. peridarion, and A. ephippium and Premnas biaculeatus. Damsel fishes that were bred successfully include Chrysiptera cyanea, C. hemicyanea Neopomacentrus cyanomos, N. nemurus, and Dascyllus carneus. The recirculating aquaculture system (RAS) designed in the Vizhinjam Regional Centre of CMFRI is being used for broodstock development of serranids, tangs, squirrel fishes, and soldier fishes. A standard method was developed for captive breeding and hatchery rearing of anthias Pseudanthias marcia and P. squamipinnis in an advanced indigenous RAS system. The present article provides a bird’s eye view of the important research work done in India concerning marine ornamental fish breeding and reviews important breeding work carried out at Vizhinjam Regional Centre of CMFRI.

The inheritance of leaf shape vis-a-vis specific leaf area and genetic parameter determining various morpho-yield related traits were studied in F2 populations of F2382 X CO17 and PBH115 x CO17 Wherein the female parent has okra type leaf and the male parent has a normal leaf. Leaf type was supposed to exhibit simple inheritance for 1:2:1 for normal leaf type, sub-okra leaf type and okra phenotypes showing incomplete dominance in both crosses. However, an attempt to associate leaf types with specific leaf areas across the segregants did not show any specific pattern indicating complexity in deducing the inheritance of specific leaf areas. Plant height, the number of bolls/plant and seed cotton yield per plant were highly variable traits. High heritability was observed for the traits viz., plant height, boll weight, ginning out turn, upper half mean length and uniformity ratio in both the crosses.

The genus Scomberomorus, with 18 nominal species, sustains a significant heterogeneous fishery throughout its range. The sole molecular systematic study of this genus concerned the species group S. regalis, which contains the new world taxa. The species diversity of Scomberomorus in the northern Indian Ocean has not been studied at the molecular level, often leading to misidentifications. Here, novel genetic data are provided that reconfigure species boundaries from the region. We used single and multilocus data (eight mitochondrial and three nuclear genes) to infer phylogenetic relationships, species delimitation, and the resurrection of a time-calibrated phylogenetic tree. Our aim was also to verify the hypothesis of geographical races in S. guttatus predicated on variable vertebral counts. Interestingly, all species delimitation analyses have recovered another highly cryptic species in the nominal S. guttatus previously believed to have an Indo-Pacific distribution. Scomberomorus guttatus (Bloch and Schneider, 1801) in the sensu stricto, is redeemed from its type locality based on genetic data and preliminary morphomeristic investigations and has a restricted distribution in the Bay of Bengal. The cryptic species Scomberomorus aff. guttatus which exhibits >10% genetic divergence from S. guttatus is resurrected here from the synonymy of the latter as Scomberomorus leopardus (Shaw, 1803). Widespread in the Indo-Pacific, this species contains two major molecular operational taxonomic units (MOTUs) with a divergence threshold of over 2% between them. Our analysis suggests that vertebral counts must be coupled with other features to identify the species/lineages in the nominal S. guttatus. The heterogeneity in the S. guttatus species group is discussed in relation to the ecological diversity of the region which facilitates larval recruitment and niche specialization. The results also revealed two allopatric putative species in S. commerson, found primarily in the Pacific and Indian Oceans. This study added genetic data from S. lineolatus and S. koreanus, not previously represented in the sequence repositories. Estimation of divergence time indicated that the Indo-West Pacific species group undergoes multiple diversification events besides the recent splits detected within S. leopardus.

The mounting tide of bovine mastitis by methicillin-resistant Staphylococcus aureus (MRSA) poses serious threat to efficacy of antibiotic treatment. Therefore, plant derived essential oils and their constituents are gaining great importance in the recent times as promising antimicrobial agents. Hence the present study was conducted to evaluate antibacterial activity of lemongrass oil (LGO) and its active principle, citral against methicillin and oxacillin resistant Staphylococcus aureus (MRSA) isolated from bovine mastitis cases. Among the 16 S. aureus organisms isolated, six isolates identified as MRSA by antibiogram against methicillin and oxacillin were selected for further study. The findings of the study indicated significant antimicrobial activity of LGO and citral as evident from their minimum inhibitory concentration (MIC) and diameter of zone of inhibition values.

With the gradual evolution of metal additive manufacturing (AM) as a viable manufacturing option for realizing complex parts, the research focus has shifted from mere geometric realization to a higher material deposition rate without a significant loss of accuracy. This work aims to demonstrate the potential of traverse twin-wire welding to produce asymmetric weld beads, providing an extra control factor in the weld bead shape and component accuracy while retaining high deposition rates. A new weld bead model - bi-polynomial fourth-order - is developed and linked to the process conditions. The higher-order model is more responsive to the weld bead shape variation and is more accurate than the traditional models. Compared to conventional single polynomial models, which are limited to the symmetrical cross-sectional weld bead, the bi-polynomial model can also simulate the asymmetrical weld bead. The process model of the weld bead and the offset are integrated with the product features to assess the time for fabrication (number of passes) and post-machining material wastage. The usefulness of the integration is demonstrated with the manufacture of a candidate multi-pass multi-layer component. It is envisaged that the investigation will facilitate large-scale wire-arc AM with the use of transverse twin-wire welding.

Antiretroviral therapy involves a combination of human immunodeficiency virus (HIV) medicines recommended for everyone who has HIV which helps them to live longer, and healthier, and reduces the risk of HIV transmission. Dolutegravir (DTG)-based antiretroviral treatment (ART) is preferred as the first-line regimen. A recently significant number of DTG-induced hyperglycaemia cases are being reported to our adverse drug reaction monitoring centre. Here, we report on five of them from March 2022 to July 2022. All five patients who were living with HIV either started or switched to ART with a tenofovir, lamivudine and DTG (TLD) regimen based on the latest guidelines for HIV treatment by the National Acquired Immune Deficiency Syndrome Control Organization (NACO). On routine checkups, the patients were found to have raised blood sugar levels; amongst them, some patients had symptoms of diabetes. All such patients were referred to the Medicine Outpatient Department, diagnosed to have type 2 diabetes mellitus and started on appropriate treatment. The TLD regimen was continued. This was categorised as per the World Health Organization (WHO) Causality Assessment Scale as "possible" category. These cases were reported to AMC and uploaded to VigiFlow. Whenever a patient has been started on a DTG-based ART regimen, the treating physician should counsel the patient about warning signs of hyperglycaemia, recommended to do periodic screening of blood sugar levels which helps in the early diagnosis and treatment of such cases. [ABSTRACT FROM AUTHOR]