bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2023.08.30.555547

Influence of pseudo-green water on growth, colouration, and survival in European lobster (Homarus gammarus) larvae

Bell, M. E.·Grady, J. O.·Domech, P. C.·Frontaura, E. R.·Hinchcliffe, J.·Davies, S. J.·McCusker, S.·Wan, A. H. L.
View original source ↗Export metadata ↓

Abstract

With the depletion of European lobster (Homarus gammarus) wild stocks from historic overexploitation, the attention has turned towards restocking, stock enhancement programs and farming potential. The early life larval stages of the European lobster present a major barrier to hatchery production efforts due to low survival rates. Green water techniques are rapidly growing due to their ability to improve nutrition quality. This study explores the potential benefits of using pseudo-green water. This is determined by adding microalgae to the rearing environment of larvae by analysing the effects on growth and survival. The commonly used algal species: Tetraselmis suecica (TS), Dunaliella salina (DS), and Nannochloropsis sp. (N) were added as monoculture or mixture treatments to a controlled European lobster larvae-rearing environment over thirteen days. The trial consisted of seven permutations of algal treatments (TS, DS, N, TS+DS, TS+N, DS+N, and TS+DS+N) and one control group, with clear water conditions using length measurements, survival rates and colouration to determine treatment impacts at the end of the trial. Results indicate that mixtures of algal species outperformed monocultures and clear water regarding growth performance. Nannochloropsis sp. is of significant benefit to growth performance. Algal mixes containing Nannochloropsis sp. resulted in significantly better growth than D. salina monoculture treatment. There were no significant differences in survival rates between treatment groups.

Explore related subjects

developmental biologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Bell, M. E., Grady, J. O., Domech, P. C., Frontaura, E. R., Hinchcliffe, J., Davies, S. J., McCusker, S., Wan, A. H. L.. 2023-08-31. Influence of pseudo-green water on growth, colouration, and survival in European lobster (Homarus gammarus) larvae. https://doi.org/10.1101/2023.08.30.555547

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Neural regulation of hatching in amphibians

Many animal embryos hatch in response to threats or opportunities, yet how cue sensing activates hatching is unknown. We screened red-eyed treefrog (Agalychnis callidryas) eggs in the field with small molecules to discover that the neurotransmitter acetylcholine is a key mediator of hatching enzyme release. Using behavioral pharmacology, microscopy, and transcriptional profiling we identify direct cholinergic input on hatching gland cells that triggers enzyme release for egg rupture, and serotonergic transduction of embryonic hypoxia sensing. Independent hypoxia-sensing and mechanosensory predation-detection pathways converge on a hatching decision that elicits acetylcholine-dependent enzyme release and coordinated hatching-specific behavior. Cholinergic regulation of hatching enzyme release is conserved in a distantly related frog and salamander, suggesting a shared ancestral hatching mechanism. These results provide a neural basis for hatching plasticity which may have contributed to the evolution of diverse hatching modes in amphibians.

developmental biology↗
bioRxiv2026

Towards Understanding the Microenvironmental Control of Reindeer Antler Regeneration

Deer antlers are the only mammalian appendages capable of complete periodic regeneration and therefore provide a natural model for investigating mechanisms of skeletal regeneration. However, current knowledge of the structural and molecular characteristics of the regenerative antler microenvironment remains incomplete. Here, we compared antler tip and antler base tissues from Rangifer tarandus (reindeer) with mature metacarpal cortical bone using structural, compositional, histological, and proteomic analyses. Antler tissues exhibited smaller and less crystalline apatite structures, elevated carbonate substitution, and higher organic matrix content compared with metacarpal bone, indicating an immature mineral phase. Antlers also exhibited lower bone mineral density, greater porosity, reduced bone volume fraction, and greater trabecular separation, particularly in central regions, consistent with a dynamic remodeling microenvironment. Histological examination revealed abundant active osteons and extensive osteoid seams in antler tissues, whereas metacarpal bone predominantly comprised mature lamellar bone with limited remodeling activity. Proteomic profiling identified distinct extracellular matrix signatures between antler and metacarpal tissues. Metacarpal bone was enriched in proteins associated with skeletal homeostasis, mechanotransduction, and bone remodeling, whereas antler tissues were enriched in proteins involved in extracellular matrix reorganization, metabolic adaptation, and regeneration. Collectively, these findings indicate that reindeer antlers possess a specialized regenerative skeletal microenvironment characterized by immature mineral organization, active remodeling, and distinct molecular signatures associated with rapid tissue growth. These results provide new insights into the biological basis of mammalian appendage regeneration and may facilitate the development of regenerative strategies for bone repair and skeletal tissue engineering.

developmental biology↗
bioRxiv2026

Endogenous expression of mutant RagC in mice results in early-onset dilated cardiomyopathy with features of the Long-Olsen-Distelmaier syndrome

Dilated cardiomyopathy (DCM) is a severe heart condition often linked to arrhythmias, clots, and heart failure, for which treatments are not yet curative. Recently, de novo mutations in genes encoding components of the Rag GTPase nutrient signaling pathway, particularly in RRAGC, have been found in unrelated patients with a severe, early-onset DCM syndrome called Long-Olsen-Distelmaier. Cancer cell lines, hiPSC-derived cardiomyocytes and zebrafish have been used to study this Ragopathy, but a mammalian model to investigate this syndrome has not been generated. Here, we show that mice engineered to endogenously express mutations in Serine 74 (orthologous to the Serine 75 mutated in patients), exhibit early-onset features of DCM with decreased heart size, fibrosis, diastolic dysfunction and aortic insufficiency, characteristics reminiscent of the human syndrome. Moreover, Rragc-mutant hearts display decreased left ventricular mass and interventricular septum. Endogenous heterozygous expression of Rragc mutant variants result in a milder, sublethal defective physiological cardiac growth with increased systolic and diastolic blood pressure. Mechanistically, active RagC does not cause abnormal increase in cardiomyocyte size, but leads to suppressed transcriptional activity of Tfeb and alterations in cardiomyocyte metabolism. Transcriptional profiling of neonatal mutant hearts reveals multiple signatures of impaired mitochondrial activity. Ex vivo and in vitro analyses of murine cardiomyocyte mitochondria from Rragc-mutant mice show suppressed mitochondrial respiration, disturbed complex IV multimerization and super-complex organization. These data point to abnormal early postnatal heart metabolism by deregulated nutrient - Rag GTPase signaling with a potential molecular explanation to the early onset of DCM in patients with de novo missense mutations in RRAGC, and suggests the relevance of early metabolic interventions in conditions with altered nutrient signaling

developmental biology↗