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Context: Mountain-top associated instream fauna with restricted ranges and limited dispersal capability are especially vulnerable to extinction under global warming and climate extremes. Aims: Rescue and housing of multiple cold-water taxa on short timelines in reaction to extreme drought. Methods: We undertook multi-species rescue (fishes: Gadopsis marmorata , n = 50; Galaxias olidus , n = 150; and a crayfish Euastacus sulcatus , n = 50) from the headwaters of the Condamine–Balonne catchment, temporarily holding animals in small (200 L) and large (1000 L) aquaria in single- and mixed-species contexts, at below 23°C. Key results: Galaxias olidus was successfully kept in one of the small aquaria, but did not survive in mixed-species aquaria, partly being due to predation by other species. Euastacus sulcatus showed decreased survivorship at moulting (predation). Large Gadopsis marmorata (>100-mm total length, TL) was aggressive, whereas maintaining smaller individuals and using large aquaria served to dampen overall aggression levels. Conclusions: Holding mixed taxa following field rescues requires attention to detail, including developmental-stage combinations within and across species, enclosure volume and availability of structure. Implications: The simultaneous rescue of multiple co-occurring endemic taxa represents a promising aspect of research and adaptive management in the era of global climate change. We rescued and temporarily housed multiple cold-water fauna (mountain-top associated fishes and crayfish) in reacting to extreme drought. In captivity, predation and aggression both within and among species reduced survivorship. Further experimentation, adaptive management and infrastructure development is required to prepare for future rescues of cold-water fauna, based on likely climate-change scenarios. This article belongs to the collection Environmental flows in northern Murray–Darling Basin: what we know about the science and management after a decade of practice. [ABSTRACT FROM AUTHOR]

Long-chain fatty acid transport protein 1 (FATP1) is a member of the fatty acid transporter family. It facilitates transmembrane transport of fatty acids and participates in lipid metabolism. Lipids are essential components of the cell and organelle membranes of Trichinella spiralis. The nematode has lost the capacity to synthesise the necessary lipids de novo and has instead evolved to obtain fatty acids and their derivatives from its host. This study aims to ascertain the primary biological characteristics and roles of T. spiralis FATP1 (TsFATP1) in lipid metabolism, larval moulting, and the development of this nematode. The results show that TsFATP1 is highly expressed at enteral T. spiralis stages, mainly localised at the cuticle, the stichosome and the intrauterine embryos of the parasite. The silencing of the TsFATP1 gene by TsFATP1-specific dsRNA significantly decreases the expression levels of TsFATP1 in the worm. It reduces the contents of ATP, triglycerides, total cholesterol, and phospholipids both in vitro and in vivo. RNAi inhibits lipid metabolism, moulting, and the growth of this nematode. The results demonstrate that TsFATP1 plays an essential role in lipid metabolism, moulting, and the development of T. spiralis. It could also be a target candidate for the anti-Trichinella vaccine and drugs. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the impact of adding fermented herbal extracts (FHE) derived from mulberry leaf (Morus alba), Javanese turmeric (Curcuma xanthorrhiza), and fingerroot (Boesenbergia rotunda) to the diet of tiger shrimp (Penaeus monodon) on their growth, moulting performance, feed efficiency, and nutrient retention. The main feed used in this trial was a commercially manufactured pellet; then, five different doses of FHE supplementation were used: 0 mL/kg feed (P0, control), 50 mL/kg feed (P1), 100 mL/kg feed (P2), 150 mL/kg feed (P3), and 200 mL/kg feed (P4). Weight gain, average daily gain, and length gain of shrimps fed P2 were significantly higher than that of those fed the control diet. A similar result was observed in moulting performance. The application of P2 showed superior results in enhancing the feed efficiency of cultured shrimp. Thus, the protein and energy retention of P. monodon was significantly better in P2 treatment groups. P0 had the lowest crude protein, while shrimp on the P2 and P3 diets had the highest crude protein content of any treatment group. Crude lipid content was lower in shrimp fed diets supplemented with FHE compared to those fed the control diet. In addition, higher energy contents were found in P1 and P2 treatment groups. Based on the findings, it is recommended that the juvenile tiger shrimp diet contain 100 mL/kg of FHE for the best effects. [ABSTRACT FROM AUTHOR]

Abstract Long-chain fatty acid transport protein 1 (FATP1) is a member of the fatty acid transporter family. It facilitates transmembrane transport of fatty acids and participates in lipid metabolism. Lipids are essential components of the cell and organelle membranes of Trichinella spiralis. The nematode has lost the capacity to synthesise the necessary lipids de novo and has instead evolved to obtain fatty acids and their derivatives from its host. This study aims to ascertain the primary biological characteristics and roles of T. spiralis FATP1 (TsFATP1) in lipid metabolism, larval moulting, and the development of this nematode. The results show that TsFATP1 is highly expressed at enteral T. spiralis stages, mainly localised at the cuticle, the stichosome and the intrauterine embryos of the parasite. The silencing of the TsFATP1 gene by TsFATP1-specific dsRNA significantly decreases the expression levels of TsFATP1 in the worm. It reduces the contents of ATP, triglycerides, total cholesterol, and phospholipids both in vitro and in vivo. RNAi inhibits lipid metabolism, moulting, and the growth of this nematode. The results demonstrate that TsFATP1 plays an essential role in lipid metabolism, moulting, and the development of T. spiralis. It could also be a target candidate for the anti-Trichinella vaccine and drugs.

Changes in wool prices, labour costs and animal welfare have sparked interest in several new sheep traits. Shedding, the ability of moulting or seasonal wool loss in sheep, is one of them. Here, we aimed to develop breeding values for shedding using existing data from New Zealand flocks. We used breeder-collected shedding scores, 0 = 'no shedding on any part of the body' to 10 = 'wool shed fully from all the body', for Wiltshire and Wiltshire-composite lambs born between 2003 and 2022. After QC, 20,653 phenotypic records from 25,066 animals with pedigree information (393 sires and 7439 dams from 12 flocks) were included in the analyses. Genetic parameters and breeding values were obtained using a genetic additive model with pedigree data (BLUP model), assuming shedding scores were quantitative. The genetic model incorporated the following variables: date of birth, sex, birth and rearing rank, age of dam and contemporary group. We found a high heritability for lamb shedding, 0.54 (0.02), and estimated a low-to-moderate prediction accuracy of breeding values (ranging from 0.09 to 0.36) using forward-validation. Our results confirmed that shedding can be subject to selection and that pedigree-based breeding values for this trait can be a useful tool for breeders. [ABSTRACT FROM AUTHOR]

Tropical rock lobsters (Panulirus ornatus) are a highly cannibalistic species with intermoult animals predominantly attacking animals during ecdysis (moulting). Rapid, positive characterisation of pre-ecdysis lobsters may open a pathway to disrupt cannibalism. Ecdysial suture line development is considered for pre-ecdysis recognition with suture line definition compared for intermoult and pre-ecdysis lobsters emerged and immerged, using white, near ultraviolet (365 nm), near infrared (850 nm), and specialty SFH 4737 broadband IR LEDs against a reference of intermoult lobsters with no suture line development. Difficulties in acquiring suture line images prompted research into pre-ecdysis characterisation from the lobster's dorsal carapace, due to its accessibility through a culture vessel's surface. In this study, a novel low-cost spectral camera was developed by coordinating an IMX219 image sensor, an AS7265x spectral sensor, and four SFH 4737 broadband infrared LEDs through a single-board computer. Images and spectral data from the lobster's dorsal carapace were acquired from intermoult, pre-ecdysis, and post-ecdysis lobsters. For the first time, suture line definition was found to be enhanced under 850 nm, 365 nm, and SFH 4737 LEDs for immerged lobsters, while the 850 nm LED achieved the best suture line definition of emerged lobsters. Although the spectral camera was unable to characterise pre-ecdysis, its development was validated when a least squares regression for binary classification decision boundary successfully separated 86.7% of post-ecdysis lobsters. Achieving post-ecdysis characterisation is the first time the dorsal carapace surface has been used to characterise a moult stage for palinurid lobsters. [ABSTRACT FROM AUTHOR]

Freshwater lobsters are one of the crustacean commodities that have started to be developed through cultivation. Besides having high nutritional value, freshwater lobsters have a stable sales value or price throughout the year. Freshwater lobster is a crustacean commodity that is not easily stressed or easily attacked by disease. The availability of calcium is essential for lobster growth, especially the formation of its shell. This research aims to determine the effectiveness of adding calcium carbonate at different time intervals by adding 150 mg/L CaCo3 lime. The study was conducted from June to July 2020 at the Aquaculture Environmental Laboratory, Bogor Agricultural Institute. The research used a Completely Randomized Design (CRD) with five treatments and three replications. The treatment used was K+ and K-, and the time interval for adding CaCo3 was once every five days, once every ten days, and once every 15 days. The aquarium measures 100 x 50 x 51 cm with a water height of 21 cm. The lobster used measures 1.5 cm. The research results after statistical testing showed that aquarium A1 (addition of CaCo3 every five days) experienced an increase in length of 0.67 cm. Weight of 0.67 g, B1 (addition of CaCo3 every ten days) experienced an increase in length of 0.87 cm and weight of 0.78 g, C1 (addition of CaCo3 every 15 days) experienced an increase in length of 0.97 cm and weight of 0.98 g, K+1 experienced an increase in length of 1.05 cm and weight of 1.06 gr, K-1 experienced an increase in length of 0.46 cm and weight of 0.45 g. [ABSTRACT FROM AUTHOR]

Substrates play an important role in the growth and survival of the freshwater crab Barytelphusa cunicularis as it is aggressive and has agonistic behaviour. An experiment was conducted to study the survival and growth performance of the freshwater crab Barytelphusa cunicularis using different substrates: T2 (Mud: Stone 50:50%), T2 (Mud: Stone 75:25%), T2 (Stone: Mud 25:75%), T2 (Mud 100%), T2 (Stone 100%), T2 (Tiles 100%), T2 (PVC pipe 100%) and T2 (Tiles: PVC pipe 50:50%). Crabs of initial average carapace width (6.3 ± 0.11cm) and average weight (80.85 ± 2.50 g) were reared in a 100 L HDPE circular tank for 60 days, crabs were fed daily trash fish at 5% of the body weight. A significantly higher carapace width gain and weight gain was observed in tiles: PVC pipe. No significant difference was observed in survival among the treated groups. This study concluded that Barytelphusa cunicularis prefers an open-tank artificial substrate. Similarly, the setup of a substrate containing tiles: PVC pipe substrate was most preferred in HDPE tanks as compared to other treatments. Tiles: PVC pipe substrate was used in successful trials for maintenance and hiding places for protection from predators, to avoid mortality rates and to minimize intraspecific struggle in Barytelphusa cunicularis. It was suggested as the best system for crab culture and maintenance. [ABSTRACT FROM AUTHOR]

Tropical rock lobsters (Panulirus ornatus) are a highly cannibalistic species with intermoult animals predominantly attacking animals during ecdysis (moulting). Rapid, positive characterisation of pre-ecdysis lobsters may open a pathway to disrupt cannibalism. Ecdysial suture line development is considered for pre-ecdysis recognition with suture line definition compared for intermoult and pre-ecdysis lobsters emerged and immerged, using white, near ultraviolet (365 nm), near infrared (850 nm), and specialty SFH 4737 broadband IR LEDs against a reference of intermoult lobsters with no suture line development. Difficulties in acquiring suture line images prompted research into pre-ecdysis characterisation from the lobster’s dorsal carapace, due to its accessibility through a culture vessel’s surface. In this study, a novel low-cost spectral camera was developed by coordinating an IMX219 image sensor, an AS7265x spectral sensor, and four SFH 4737 broadband infrared LEDs through a single-board computer. Images and spectral data from the lobster’s dorsal carapace were acquired from intermoult, pre-ecdysis, and post-ecdysis lobsters. For the first time, suture line definition was found to be enhanced under 850 nm, 365 nm, and SFH 4737 LEDs for immerged lobsters, while the 850 nm LED achieved the best suture line definition of emerged lobsters. Although the spectral camera was unable to characterise pre-ecdysis, its development was validated when a least squares regression for binary classification decision boundary successfully separated 86.7% of post-ecdysis lobsters. Achieving post-ecdysis characterisation is the first time the dorsal carapace surface has been used to characterise a moult stage for palinurid lobsters.

We studied the life history of the New River Crayfish, Cambarus chasmodactylus in Anthony, Creek, West Virginia during an entire activity season—from May 2011 through October 2011. We observed two mass moulting events; one occurred in May, whereas the other occurred in September. Most males within this population moulted from Form I (i.e. reproductive form) to Form II (i.e. non‐reproductive form) in May and then later returned to Form I after a September moulting event. We collected females with active glair glands from May to June, with oviposition occurring from July to August. Fecundity was high and weakly correlated with body size. Egg counts of attached eggs/young in ovigerous females ranged from 41 to 281, with an average of 168. Additionally, from June to October, we dissected a subset of females to determine the monthly gonadal development in females with and without active glair glands. Lastly, in the laboratory, we observed 4th instar neonate crayfishes repeatedly "drifting" between females. We speculate on the relevance of this drifting behaviour and propose future studies to investigate this phenomenon. Our study provides the first comprehensive understanding of the life history of C. chasmodactylus. [ABSTRACT FROM AUTHOR]

The aim of the study was to compare three moulting procedures and their effect on productive performance, egg quality, and antibody response of leghorn hens. For this, a total of 324 laying hens were distributed into three treatment groups having 12 replicates of 9 birds each according to completely randomized design. Treatments consisted of three moulting procedures based on feed and light restriction. The targeted weight at the end of moulting was 1450–1470 g. As soon as the moulting procedure is complete, the comparative analysis of post-moult productive performance (feed intake, egg production, egg weight, egg mass, feed per dozen eggs, feed per kg egg mass, livability), egg quality characteristics (egg weight, egg length and width, shape index, surface area, volume, albumen height, weight, Haugh unit score, yolk width, height, index, egg shell pore number, shell weight, thickness, breaking strength), and antibody response against Newcastle disease and avian influenza (H-9) were evaluated. Birds subjected to moulting procedure 3 (8 days fasting and gradual decrease in light) showed improvement in productive performance, egg geometry and quality traits, and antibody response against Newcastle disease virus. Birds experienced moulting procedure 1 (11 days fasting) had improved feed intake, egg production, and livability. However, birds moulted with procedure 2 (6 days fasting) revealed intermediate result in all the studied parameters. In conclusion, moulting through feed and light restriction with 8 days fasting and gradual reduction in light has potential to improve performance of leghorn hens. [ABSTRACT FROM AUTHOR]

RNA interference (RNAi) is a technique employed to investigate the functions of various genes in whitefly and other insects. The effectiveness of the RNAi technique depends upon the delivery of dsRNA into the insects and it has been achieved through microinjection, oral feeding, egg soaking, transfection, topical application, spraying with nanoparticles, leaf‐mediated dsRNA feeding or plant‐mediated/ transgenic plants. In Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), most of the studies on RNAi were conducted on the adult through either injection or oral feeding. There is a need to develop a system to deliver dsRNA in whitefly nymphs because the first instar nymphs after hatching find a suitable place on the leaf and feed on the same place till adult emergence. So, we evaluated nine different techniques using different sponges, tubes, and, Petri plates for feeding nymphs. The detached leaf survived for maximum number of days (8.25 days) with minimum nymphal mortality (12.01%) in the Whitefly Nymphal Feeding System‐1 (WNFS‐1) treatment; therefore, WNFS‐1 was selected for the delivery of dsRNA to B. tabaci nymphs. In WNFS‐1, blue food dye was used to confirm that nymphs were being fed, and the results were evidenced by blue‐coloured bodies. The juvenile hormone esterase (jhe) gene was silenced in order to successfully deliver dsRNA to nymphs using WNFS‐1 and resulting in much higher nymphal mortality (68.36%). Therefore, WNFS‐1 is a reliable method of delivering dsRNA for the purpose of silencing the genes in the nymphal stages of whiteflies. The WNFS system may also be used extensively to evaluate any chemistry (insecticides, hormones, biopesticides, etc.) in nymphs of whitefly. [ABSTRACT FROM AUTHOR]

An in silico docking study was performed to evaluate the interaction of various triterpenoids present in neem with the ecdysone receptor of two economically important lepidopteran pests viz., Helicoverpa armigera (HaEcR) and Plutella xylostella (PxEcR). Twenty triterpenoids were selected for the study, and their docking scores with HaEcR and PxEcR were calculated using the program AutoDock Vina. A commercially available DAH insecticide, tebufenozide, was used as a reference ligand. Out of the twenty triterpenoids used for the study, six and nine triterpenoids recorded binding energy lower than the reference ligand, tebufenozide, when docked with HaEcR and PxEcR, respectively. Four triterpenoids, viz., isomeldenin, azdiradione, 6-deacetylnimbinene, and nimocinol, docked effectively with the ecdysone receptor of both insect pests. In addition, nimbinene and 6-deacetylnimbin also docked effectively with HaEcR and epoxyazadiradione and nimbocinol with PxEcR. Most of the lead compounds were able to form hydrogen bonds with the ecdysone receptor molecule. We found two key amino acid residues, Asn of HaEcR and Ser of PxEcR, at the 504th position, based on their ability to form hydrogen bonds with many lead triterpenoids tested. Other residues, such as Trp 526 in HaEcR and Lys 372 and Phe 520 in PxEcR, were involved in hydrophobic and π-π stacking interactions with many lead triterpenoids, suggesting these residues as an important point of interaction between receptor and ligand molecules. Triterpenoids such as tirucallol, 3-tigloylazadirachtol, and azadirone, although recorded binding energy lower than tebufenozide when docked with PxEcR, failed the prerequisite conditions laid down by Tice rule for a successful pesticide. The lower binding energy of the lead compounds suggests their stable interaction with the receptor molecule and their possible use as an ecdysone agonist or antagonist for effective insect control. [ABSTRACT FROM AUTHOR]

Aggression in territorial social systems is easy to interpret because the benefits of territorial defence mostly accrue to the territorial holder. However, in non-territorial systems, high aggression seems puzzling and raises intriguing evolutionary questions. We describe extreme rates of despotism between age classes in a passerine bird, the painted bunting (Passerina ciris), during the pre-moulting period. Aggressive encounters were not associated with aggressors gaining immediate access to resources. Instead, conspecifics, and even other species, were pursued as though being harassed; this aggression generated an ideal despotic habitat distribution such that densities of adult males were higher in high-quality sites. Aggression was not a by-product of elevated testosterone carried over from the breeding season but, rather, appeared associated with dehydroepiandrosterone, a hormone that changes rates of aggression in non-breeding birds without generating the detrimental effects of high testosterone titres that control aggression in the breeding season. This extraordinary pre-moult aggression seems puzzling because individual buntings do not hold defined territories during their moult. We speculate that this high aggression evolved as a means of regulating the number of conspecifics that moulted in what were historically small habitat patches with limited food for supporting the extremely rapid moults of painted buntings.

Trilobites were notably flexible in the moulting behaviours they employed, producing a variety of moult configurations preserved in the fossil record. Investigations seeking to explain this moulting variability and its potential impacts are few, despite abundant material being available for study. We present the first quantitative study on moulting in a single trilobite species using a dataset of almost 500 moult specimens of Estaingia bilobata from the Cambrian (Series 2, Stage 4) Emu Bay Shale, South Australia. Specimens were categorized by moulting mode (Salter's or Sutural Gape) and their associated configurations, and their body proportions measured from both a museum collection (including a bycatch sample) and a randomly‐collected field sample. This enabled analysis of the proportion of E. bilobata specimens displaying the Sutural Gape and Salter's modes of moulting and their different configurations, and tests for association between moulting behaviour and body proportions. The results show a wide range of E. bilobata moulting configurations in all samples, suggesting that configurations represent definable instances in a largely continuous spectrum of variation. Analyses comparing body proportions of specimens showing the two modes of moulting were non‐significant, suggesting there is no true association between moulting behaviour and body proportion, except for a single significant result for body length. All results were relatively consistent between the museum and field samples. However, removing accessioned specimens from the museum sample brought results even further in line with the field sample, supporting the need for consideration of museum collection bias in palaeontological analyses. [ABSTRACT FROM AUTHOR]

Simple Summary: Ammonia is the most common contaminant in aquaculture systems, including intensive hatchery systems for crustaceans. Although it has been demonstrated that ammonia can result in abortive moulting and massive mortality of juvenile crustaceans, the underlying mechanisms are still unknown. The present work is aimed at examining the effect of ammonia exposure on the moulting process as well as molt signaling in the swimming crab Portunus trituberculatus, an important aquaculture species in China. We examined the survival rate and moulting rate of the juvenile crabs (C2) and analyzed the expression pattern of the genes in key components of molt signaling during a complete moulting cycle under different concentrations of ammonia. Our results revealed that ammonia has dose-dependent biphasic effects on moulting in juvenile swimming crab. Specifically, low levels of ammonia (5 mg/L) stimulated moulting, while high levels of ammonia (20 mg/L) suppressed the moulting process and caused moulting death syndrome (MDS). The gene expression analysis indicated that low levels of ammonia can reduce the expression of MIH, which encodes the key negative regulator of moulting, and trigger ecdysteroid biosynthesis and ecdysteroid signaling in the juvenile crabs. In contrast, though the high level of ammonia increased MIH expression, it still resulted in excessive ecdysteroids and over-activation of ecdysteroid signaling, which may contribute to the depressed moulting and MDS in the juvenile crabs. The novel findings of this study improve the understanding of ammonia toxicity in brachyura and provide valuable information for hatchery management of P. trituberculatus. Ammonia is a significant concern during hatchery culture in brachyuran species, and its accumulation may lead to abortive moulting and large-scale deaths of the early juveniles. To date, the underlying mechanism for ammonia-induced alteration of the moulting process is still unknown. In this study, we aimed to investigate the effects of ammonia on the moulting as well as the potential mechanisms in early juveniles of the swimming crab Portunus trituberculatus, an important aquaculture species in China. We evaluated the survival rate and moulting rate of the juvenile crabs (C2) and analyzed the expression pattern of the genes in key components of molt signaling during a complete moulting cycle under different concentrations of ammonia nitrogen (the control group: <0.1 mg/L; the LA group: 5 mg/L; and the HA group: 20 mg/L). The results showed that: (1) the survival rate in the LA and HA groups was lower than that in the control group at the end of the experiment, and moulting death syndrome (MDS) was only observed in the HA group; (2) the moulting rate was higher in the LA group and lower in the HA group compared to the control group; (3) consistent with the results of the moulting experiment, MIH showed decreased expression, and genes related to ecdysteroid synthesis, ecdysteroid receptors, and responsive effectors exhibited increased expression in the LA group compared to the control group; and (4) although MIH expression was upregulated, increased expression of the genes associated with ecdysteroid synthesis, ecdysteroid receptors and downstream effectors still observed in the HA group. Our results indicated that low levels of ammonia can promote moulting in juvenile swimming crabs by inhibiting the expression of MIH and activating moult signaling, whereas high levels of ammonia inhibit moulting and lead to MDS through impairing moult signaling. [ABSTRACT FROM AUTHOR]

Exoskeleton moulting is the process of shedding the old exoskeleton to enable growth, development and repair, representing a crucial recurrent event in the life histories of all euarthropods. The fossil record of moulting allows us to interpret the evolution of this important behaviour and its impact on the evolutionary trajectories of extinct and extant euarthropods. Current knowledge of Palaeozoic euarthropod moulting relates largely to trilobites, with fewer examples known for non-mineralised extinct taxa from early in euarthropod evolutionary history. We describe exuviae from a marrellid marrellomorph found abundantly in the Early Ordovician Fezouata Shale Lagerstätte of Morocco, which allow a novel reconstruction, the second ever, of marrellid moulting behaviours. We identify the moulting suture location, describe preserved moulting assemblages, and suggest how its moulting behaviours are adaptive to its morphology. Several specimens represent complete and nearly complete assemblages and additional disarticulated specimens confirm the suture line location. The suture line is located between the mediolateral and posterolateral spine pairs, dividing the cephalic shield into anterior and posterior parts. The Fezouata marrellid likely exited the exoskeleton during exuviation using posterior and upwards movements, analogous in terms of movement to lobster-like extant arthropods. The suture line is comparable in the closely related marrellid Mimetaster, and distinctive from that of another marrellid, Marrella splendens, which has an exuvial opening at the anterior of the cephalic shield and exited the exoskeleton anteriorly. This difference in moulting behaviour as compared to Marrella is likely adaptive to the greater complexity of the Fezouata marrellid, with upwards rather than forwards movement presumably providing a more favourable angle for the extraction of complex spines. This description of the moulting behaviours and related morphological features of marrellomorphs expands our understanding of this crucial characteristic in extinct euarthropods.

Various approaches for the induction of moulting have been explained in the literature review, however, there is a dire need to explore other effective methods that can be more efficient in terms of production performance. The current study was conducted to evaluate the role of zinc-induced moulting on certain body performance attributes, serum biochemical profile and serum hormonal profile of White Leghorn layers towards the end of their first production cycle (spent layers). Commercial White Leghorn birds (n=24) of 67-weeks of age were procured from local market and were induced to moult with zinc oxide (3 g/kg diet) for three consecutive weeks. The spent layers were grouped as non-moulted group (NML) and moulted group (ML) after zinc-induced moulting. The result on overall body performance attributes indicated that the body weight and weight of organs significantly (P=0.05) decreased in ML group birds as compared to the birds of NML group except for kidneys. The cholesterol, HDL, LDL and triglycerides were lower (P=0.05) in birds of ML group as compared to birds of NML. On the contrary, serum circulating levels of ALT and AST were statistically higher (P=0.05) in birds of ML group as compared to their counterpart NML group. A significant increase (P=0.05) was noticed in serum T4 and cortisol concentrations for birds of ML group as compared to those of NML group, whereas T3 level was found decreased (P=0.05) in birds of ML group. The results of present study indicated that usage of dietary supplementation of ZnO (3g/kg), for the purpose of moulting, exhibits promising effects on body performance attributes and serum biomarkers. Different dietary concentrations of ZnO may be evaluated in future to minimize stress and further enhance the performance of spent layers. [ABSTRACT FROM AUTHOR]

In aquaculture, high mortality in crustacean larvae during the moulting process restricts the larviculture's productivity. This study aimed to determine the bioactive components in the methanolic extract of fiddlehead ferns, Diplazium esculentum, and their effects on the growth of Microbrachium rosenbergii postlarvae (PL). Hormonal analysis revealed a high level of 20-hydroxyecdysteroid (20E) hormone in both leaves and shoot parts (4733 pg/ml) with the presence of phenols, tannins, saponins, flavonoids, terpenoids, alkaloids, and steroids during the phytochemical screening. GC–MS analysis discovered the presence of thirty-two bioactive compounds, including 1-(2,6-dichlorobenzoyl)-2,5-dimethylpyrrole, decyl sulfide, beta-amyrin, and cyclotetrasiloxane, octamethyl- with the peak area of 12.60%, 10.81%, 10.46%, and 8.48%, respectively. During a pilot study, prawn PL were fed diets containing D. esculentum extracts, namely diet 1–diet 5, with concentrations of 0.5, 1.0, 2.0, 4.0, and 10.0 gkg−1, respectively. Results showed high survival in PL fed with diet 4 and diet 5 (75.56% and 77.22%, respectively; p = 0.049). Next, a 60-day feeding trial was conducted to determine the moulting and growth performance of PL fed with 0 gkg−1 (control), 4.0 gkg−1 (diet 4), and 10.0 gkg−1 (diet 5) fern extracts. Results showed that prawns fed with diet 5 significantly showed the highest moulting frequency (112 ± 1.32 moults) and moulting rate (2.04 ± 0.02 moults per prawn). The findings demonstrated that a higher concentration of 20E with the highest inclusion of D. esculentum in diets could have enhanced the moulting performance in M. rosenbergii. We suggest an experiment on nutrient-dose response to determining the optimum level for growth performance in M. rosenbergii. [ABSTRACT FROM AUTHOR]

Scylla paramamosain is an importantly economical mariculture crab. To figure out the optimized conditions in the culture of juvenile crabs, three experiments were conducted to examine the effects of diet, salinity and light condition on the growth performance (body weight gain, BWG; carapace width gain, CWG; carapace length gain, CLG) and moulting cycle (MC) of crablets from V to VII stages. The growth performances of the crablets from stages V–VII have no significant differences after feeding different diets. However, the MC of crablet V fed Artemia or mixed fish were significantly shorter than that fed artificial diet. The CLG of crablet VI in salinity 25‰ was significantly higher than that in salinity 15‰, while the CWG and CLG of crablet VII in salinity 15‰ were significantly higher than that in salinity 5‰. The MC of the crablets V–VI reared in salinity 25‰ and 15‰ were significantly shorter than that in salinity 5‰, while it was significantly shorter in salinity 25‰ than that in salinity 15‰ from crablets VI–VII. For light conditions, the BWG of crablet VI with full cover was significantly higher than that with half cover. Whereas, the MC of the crablets V and VI with full cover was significantly shorter than that without cover or half cover. These findings indicated that crablet V and VI may prefer to exposing to 25‰ salinity and dark environment and feeding on Artemia for faster growth. Thus, the current findings may serve as a guide for establishing appropriate conditions in the aquaculture of juvenile mud crabs. [ABSTRACT FROM AUTHOR]

Intracellular calcium (Ca2+) is vital for signal transduction in many cellular events. Several Ca2+‐binding proteins mediate the transduction of intracellular calcium signals. The EF‐hand motifs containing neuronal calcium sensor (NCS) proteins are mainly expressed in the nervous system, where they have important roles in the regulation of a variety of neuronal functions. NCS1 has four EF‐hand motifs and well‐defined neuronal development functions in a variety of eukaryotes. However, NCS2 has only been identified in invertebrates such as insects and nematodes thus far. The functions of NCS2 remain largely unknown. Here, we identified an orthologous NCS2 in the hemipteran Nilaparvata lugens. Based on qRT‐PCR, this gene was found to be primarily expressed in the brain. Knockdown of NCS2 in each nymphal instar by RNA interference led to lethality and caused aggradation and disordered arrangement of lipid droplets in the ovaries and testes of adults, which were associated with the absence of mature oocytes in female ovaries and reduction of spermiation in male adults. Our findings revealed a novel function for NCS2 as a regulator in development and reproduction and suggested that this protein had an important role in modulating lipid droplet remodelling in ovary and testis of N. lugens adults. [ABSTRACT FROM AUTHOR]

1. Moulting is a natural physiological process in birds when they shed their old feathers and replace them with new ones, and it is followed by reproductive quiescence resulting in reduced egg production. Different birds undergo moulting at different points in their life. Some birds have seasonal moulting while some moult at the end of their breeding cycle. This review will mainly focus on moulting practices associated with commercial layer birds because, in all other bird types, this is not managed. 2. Commercial farms commonly analyse the cost–benefit ratio to decide the time and method to adopt for moulting. Commercial layer farms adopt different practices to force birds out of moult and restart the production cycle. Animal welfare groups consider this as stressful and against animal welfare, raising questions about the ethics of this practice. 3. Many studies have been conducted using complete or partial feed withdrawal and non-feed withdrawal programs to measure their effectiveness in maintaining animal welfare, economy, and post-moult performance in mind. 4. Animal welfare should not be compromised during moulting. The United States Egg Producers and other such groups from the United Kingdom and Europe have decided to sell eggs produced only through a non-feed withdrawal moulting programs. [ABSTRACT FROM AUTHOR]

Moult is an energetically demanding period, during which flight may be impaired and foraging ranges may become constrained. During the non‐breeding period, Great Ardenna gravis and Sooty Ardenna grisea Shearwaters migrate from South Atlantic breeding colonies to aggregate at North Atlantic feeding grounds. We investigated whether both shearwater species used coastal Newfoundland, Canada, as a moulting area and used stable isotope ratios (δ15N, δ13C) of recently moulted primary feathers (P1, P5, P10) to infer moult location/diet for both species. Moult scores indicated that both species finished their moult (i.e. P6–10) in coastal Newfoundland, which was further corroborated with similar stable isotope ratios for Great (δ15N = 15.17 ± 1.13‰; δ13C = −18.66 ± 0.54‰) and Sooty Shearwaters (15.54 ± 0.74‰; −18.43 ± 0.78‰); however, Sooty Shearwater moult was more advanced relative to that of Great Shearwater. In contrast, isotopic ratios of P1 and P5, which were grown before arriving in coastal Newfoundland, differed between and within species, suggesting divergent locations/diet during early moult. For Great Shearwaters, P1/P5 isotopic ratios were more variable (broader niche breadth) than P10, suggesting that some individuals started moulting in the South Atlantic prior to trans‐equatorial migration, whereas others start moulting in the North Atlantic Ocean. Sooty Shearwaters had two distinct groupings of either higher or lower δ15N in P1/P5, suggesting that individuals began moulting either on the Newfoundland Shelf or further offshore based on comparisons to reference shearwater feathers grown in known locations. These findings illustrate distinct locations and/or diets at the start of primary feather moult, both within and between species, but diets converged when aggregated together at the end of moult in coastal North America, where growing feathers of both species were sampled. More importantly, we identified an important area for both Sooty and Great Shearwaters to complete their moult in coastal Newfoundland. Protecting this moulting area would minimize disturbance and the impacts of threats (e.g. by‐catch) to both species during this energetically demanding period. The area has been suggested previously to be an important candidate area for protection due to annually persistent prey aggregations that can be spatiotemporally delimited based on specific prey habitat requirements. [ABSTRACT FROM AUTHOR]

Ca2+ plays an important role in signal transduction and regulates various physiological functions of cells. The active transport of Ca2+ from the cytosol to the lumen of the sarcoplasmic or endoplasmic reticulum occurs via sarco/endoplasmic reticulum Ca2+‐ATPases (SERCA). However, the function of this protein during moulting cycles remains unclear in Chinese mitten crab (Eriocheir sinensis). In this study, we cloned a cDNA encoding a putative SERCA protein from the Y‐organs (moulting glands) in E. sinensis. The cloned Es‐SERCA cDNA (4552 bp) included an open reading frame of 3003 bp encoding a 1000‐residue protein with a predicted molecular mass of 109.60 kDa. The predicted Es‐SERCA protein was clustered with those from other arthropods in phylogenetic analysis. Further, qPCR revealed that Es‐SERCA was widely expressed in in all tested tissues with the highest expression in the muscle, followed by the eyestalks, intestines, hepatopancreas, Y‐organs and gills. The stage‐specific fluctuations among different tissues indicated a functional role of SERCA in calcium homeostasis. The relative mRNA level of the Es‐SERCA in Y‐organs during the moulting cycle was similar to the level trend of ecdysteroid concentration in haemolymph, indicating that Ca2+ signalling stimulated ecdysteroid synthesis in Y‐organs. Altogether, our study provides a reference for further research on the molecular mechanisms of the moulting in E. sinensis. [ABSTRACT FROM AUTHOR]

1. Cobb and Ross broilers (200 of each sex and breed) were fed four phases of diets ad libitum formulated with balanced protein to match their amino acid requirements throughout growth. Ten birds per genotype were sampled and euthanised at two-weekly intervals from 14 to 112 d of age. All feathers were dry-plucked from each of the seven tracts (specific skin areas) and pulp (the centre of the feather filament) was removed from primary and secondary remiges. 2. Daily losses of feathers were collected from an additional 20 individually-caged broilers of each breed. These feathers were separated into natal down, contour feathers, remiges and rectrices and then pooled by type, sex and genotype to quantify water and protein contents. Only those feathers collected from male Cobb 500 MX broilers were analysed for amino acid content. 3. Amino acid contents of feathers from the seven tracts were measured only in Cobb males on days 1, 28 and 70; for pulp on days 28 and 70; and for the four types of moulted feathers. 4. Protein content on a dry matter basis remained relatively constant over all ages and tracts during growth. Water content decreased with age in both sexes and genotype. Lysine and methionine content in feathers decreased with age while cystine, valine, leucine and serine increased. Lysine, methionine and histidine levels were higher in pulp than in mature feathers whereas cystine and valine were higher in mature feathers than in pulp. 5. These results, together with information about moulting patterns in broilers, enabled the effects of age of the bird and of the type of feather, to be taken into account when determining the rate of deposition of amino acids in feathers. [ABSTRACT FROM AUTHOR]

H. viswakarma Dhiman, is a endoparasite of L.augur, which in turn is a pest of S. oleosa plant. Emergence and moulting behaviour of this parasite is observed in field and laboratory. Both penetration of preparasitic juveniles with in the host body and emergence of parasitic stage from the host takes place through weak body points such as joints of legs, antennae, tergites, pleurites, sternites, wing axillaries and external genitalia. Emergence lasts for an average 5.5 minutes. Time taken from penetration till emergence lasts for an average 20.5 days. All stages except the eggs of the nematode moults and remove their exocuticle. Post parasitic stage moults into soil after an average of 23 days. [ABSTRACT FROM AUTHOR]

Marine animals such as the southern elephant seal (Mirounga leonina) rely on a productive marine environment and are vulnerable to oceanic changes that can affect their reproduction and survival rates. Davis Base, Antarctica, acts as a moulting site for southern elephant seals that forage in Prydz Bay, but the mitochondrial haplotype diversity and natal source populations of these seals have not been characterized. In this study, we combined genetic and animal tracking data on these moulting seals to identify levels of mitochondrial haplotype diversity, natal source population, and movement behaviours during foraging and haul-out periods. Using partial sequences of the mitochondrial control region, we identified two major breeding mitochondrial lineages of seals at Davis Base. We found that the majority of the seals originated from breeding stocks within the South Atlantic Ocean and South Indian Ocean. One seal was grouped with the Macquarie Island breeding stock (South Pacific Ocean). The Macquarie Island population, unlike the other two stocks, is decreasing in size. Tracking data revealed long-distance foraging activity of the Macquarie Island seal around Crozet Islands. We speculate that changes to the Antarctic marine environment can result in a shift in foraging and movement strategies, which subsequently affects seal population growth rates. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), a synthetic organic compound widely used in the production of plastics, is recognized as an emerging contaminant because of its toxicity and the potential risks associated with bioaccumulation in organisms. Despite potential environmental hazards, there is a lack of studies examining BPA toxicity mechanisms and its potential impact on various trophic levels, with even fewer exploring whether global stressors such as temperature can affect the toxicity of BPA in organisms. Our aim was to assess the combined impact of BPA and varying temperature regimes on life-history traits in Daphnia magna. Our results revealed a significant impact of BPA on the growth, reproduction, and accumulated moulting of D. magna , with adverse effects primarily associated with the assimilation of BPA in algae rather than the BPA present in the medium, pointing to a trophic transfer mechanism. The interactive effect between BPA and temperature demonstrated a slight stimulatory effect of low BPA level on D. magna growth rate under warming constant conditions, but an inhibitory under warming fluctuating temperatures. Additionally, a BPA threshold was identified, below which growth became temperature-dependent. This study emphasizes the crucial role of considering temperature in predicting how toxins may affect Daphnia within aquatic food webs. [Display omitted] • Realistic BPA levels negatively affected life-history traits of Daphnia magna. • Harmful BPA-effects on D. magna were primarily mediated by BPA-assimilated in food. • BPA effect on D. magna was modulated by temperature at low BPA levels. • D. magna growth was temperature-dependent below a BPA threshold. [ABSTRACT FROM AUTHOR]

• A long duration low amplitude signal segment distinguishes intermoult lobsters. • A 7 MHz centre frequency transducer generates the distinguishing signal segment. • Pre-moult structural changes beneath the exoskeleton explain changed response. • A foundation is indicated for an NDT based ultrasonic crustacean pre-moult detector. • Valuable insights of acoustic interactions with the lobster exoskeleton are presented. This study examined the novel application of non-destructive testing (NDT) ultrasound for detecting approaching moult in juvenile tropical rock lobsters (TRL), Panulirus ornatus. TRL juveniles are highly cannibalistic in culture, with up to 25% of lobsters lost to cannibalism at each moult. A pre-moult sensor could prove pivotal as moulting lobsters are the primary victim of cannibalistic predation and a reliable indication of pre-moult could trigger a suitable intervention measure. A series of structural changes take place beneath the exoskeleton in preparation for moulting, which leave little indication of pre-moult on the lobster's external surface. An opportunity exists for penetrative pre-moult detection via ultrasonic acoustic stimulation through the exoskeleton. NDT ultrasound is proposed as a possible pre-moult sensing technology. NDT ultrasound is comparatively low-cost, a requirement for replicated deployment to industry. This study explores the acoustic response from five NDT ultrasound transducers by scanning the dorsal carapace of juvenile TRLs. A small diameter (13 mm) transducer with a 7 MHz centre frequency produced and measured a low amplitude, long duration signal segment in intermoult lobsters that was not present in pre-moult lobsters, forming a basis to distinguish intermoult from pre-moult lobsters. It is proposed that muscle detachment and growth of the new integument and a separating membrane disrupt sound conduction beneath the exoskeleton in a similar fashion to delaminated joint detection methods used in industry. These results show promise that a pre-moult sensor may be able to be based on NDT ultrasonic technologies and provide guidance for refining transducer specifications for further research. [ABSTRACT FROM AUTHOR]

Ammonia is a significant concern during hatchery culture in brachyuran species, and its accumulation may lead to abortive moulting and large-scale deaths of the early juveniles. To date, the underlying mechanism for ammonia-induced alteration of the moulting process is still unknown. In this study, we aimed to investigate the effects of ammonia on the moulting as well as the potential mechanisms in early juveniles of the swimming crab Portunus trituberculatus, an important aquaculture species in China. We evaluated the survival rate and moulting rate of the juvenile crabs (C2) and analyzed the expression pattern of the genes in key components of molt signaling during a complete moulting cycle under different concentrations of ammonia nitrogen (the control group: MIH showed decreased expression, and genes related to ecdysteroid synthesis, ecdysteroid receptors, and responsive effectors exhibited increased expression in the LA group compared to the control group; and (4) although MIH expression was upregulated, increased expression of the genes associated with ecdysteroid synthesis, ecdysteroid receptors and downstream effectors still observed in the HA group. Our results indicated that low levels of ammonia can promote moulting in juvenile swimming crabs by inhibiting the expression of MIH and activating moult signaling, whereas high levels of ammonia inhibit moulting and lead to MDS through impairing moult signaling.

Whilst southern elephant seals Mirounga leonina inhabit the Southern Ocean, hauling out on sub-Antarctic islands, individuals are frequently encountered further north, on southern hemisphere continents. It is unknown whether these animals are merely vagrants or whether they are individuals using the extremes of their range. A single adult male, identified by characteristic scars, was sighted 37 times from 2008 to 2021 at Possession Island, Namibia. The timing of sightings indicates that this individual must have remained in African waters between at least some of its haul-outs, rather than returning to the Southern Ocean. Similar observations have been reported anecdotally for other individual adult male elephant seals on the southern African coast, whilst adult females pupping in this area are extremely rare. Although records of vagrant southern elephant seals hauling out on the southern African coast remain rare, whether they are single or repeated visits, in some instances repeated haul-outs represent dispersion to rewarding foraging areas. [ABSTRACT FROM AUTHOR]

Moulting is critical for growth, development and survival in insects. As the main components of cuticle, dynamic change of chitin is consistent with the moulting process. Chitinase is the main enzyme to mediate chitin metabolism in the old cuticle. To avoid over‐degrading chitin from the new cuticle, the expression of chitinase must be precisely regulated. In this study, we performed microRNA‐sequencing to investigate expression change of microRNAs in silkworm epidermis during the moulting process. A comparative microRNA transcriptomic analysis from different moulting stages and 20‐hydroxyecdysone (20E) treatment identified bmo‐miR‐282‐5p as a candidate. By the bioinformatic analysis, chitinase 5 (BmCht5) was predicted to be a target of bmo‐miR‐282‐5p. Meanwhile, a temporal expression analysis revealed that BmCht5 only expressed at moulting D3 stage, whereas bmo‐miR‐282‐5p showed a converse pattern, in which its transcript signal disappeared at this time point. Furthermore, a luciferase assay and agomir treatment demonstrated that bmo‐miR‐282‐5p suppressed transcript of BmCht5 in vivo. As a result, injection of 282‐5p agomir triggered 40% death due to moulting failure. In addition, RNA interference (RNAi)‐mediated silencing of BmCht5 caused 30% developmental defect. Taken together, our data demonstrate the coordinated regulation of chitinase 5 by conserved miR‐282‐5p, and the 20E signalling pathway is essential for the normal moulting process in the domesticated silkworm. [ABSTRACT FROM AUTHOR]

The purpose of this paper was to determine the evolution of the blood biochemical profile in 63-week-old Hy-Line var. Brown hens, in natural moulting conditions. A control group that showed no signs of moulting and a spontaneously moulted hen group were monitored for eight weeks. The analysed blood biochemical parameters were: glucose, total protein, uric acid, cholesterol, calcium and phosphate concentrations, and Ca/P ratio. All analysed parameters recorded different levels in the moulting period, compared to those in the period before this physiological process. The hens in the moulting group showed significant (P<0.01) variations in serum glucose compared to those in the control group where these variations did not differ significantly. Glucose raised by 19%, uric acid decreased by 2.9% and total serum proteins also decreased by 23.89% compared to the control group. Cholesterol of the moulting group reached its highest values raising with 100% and Ca/P ratio had a decreasing with 5.1% compared to the control group. Thus, it can be stated that the determination of the biochemical profile is useful in the evaluation of the physiological status of moulting hens. [ABSTRACT FROM AUTHOR]

In this study, the effect of some biotic (total length, sex) and abiotic (sampling station and month) factors on the shell status (soft or hard) of Pontastacus leptodactylus were investigated in a natural crayfish population. The study was carried out in Hirfanlı Dam Lake (Central Anatolia), where one of the most important crayfish harvesting areas of Turkey, with a monthly basis between Jun-2017 and May-2018. Permutational multivariate analysis of variance (PERMANOVA) was used for the determination of the differences between nonparametric variables. A total of 5920 crayfish were checked, ultimately determined as 106 (1.79%) individuals with a soft shell and 5814 (98.21%) hard shell. Shell status was shown statistical difference with total length, stations, and sampling month (p<0.05), while it was no significant by sex group (p>0.05). [ABSTRACT FROM AUTHOR]

The insect growth regulator NC-184, a juvenile hormone mimic, prevents moulting to the adult stage in the desert locust, Schistocerca gregaria (Forskål) (Orthoptera: Acrididae). Male nymphs treated in the penultimate or final nymphal instar with NC-184 exhibit precocious mating behaviour in the final instar. We examined whether this chemical affects the development of the internal reproductive organs of crowded nymphs. In treated males, both accessory glands and seminal vesicles were underdeveloped, and no sperm was found in the seminal vesicle, whereas these organs in control individuals had greatly increased in size 10 days after treatment, when all the insects had moulted to adults. Testis size in treated males was similar to that in controls, regardless of their smaller body size due to the inhibition of moulting. Oogenesis and development of spermatheca in females treated with NC-184 continued to some degree, but no eggs matured, unlike what occurred in the control. In conclusion, treatment of S. gregaria nymphs with NC-184 resulted in changes in the reproductive organs in both sexes.

The myeloid differentiation factor 2 (MD-2)-related lipid-recognition protein is involved in immune responses through recognizing bacteria lipopolysaccharide in mammals, arthropods and plants. However, the physiological roles of MD-2 in other biological processes are largely unknown. Here, we identified three homologue MD-2 genes (NlML1, NlML2 and NlML3) by searching the genome and transcriptome databases of the brown planthopper Nilaparvata lugens, a hemipteran insect species. Temporospatial analysis showed that the NlML1 gene was highly expressed in the fat body but much less so in the other tissues, while the NlML2 and NlML3 genes were highly expressed in the testis or digestive tract. RNA interference-mediated depletion of the NlML1 gene significantly downregulated the transcription of numerous integument protein genes. The NlML1 knockdown led to moulting failure and mortality at the nymph–adult transition phase, impaired egg laying and hatching, and reduced 20-hydroxyecdysone (20E) production in the nymphs. 20E could rescue the deficient moulting phenotypes derived from dsNlML1 RNAi. These novel findings indicate that NlML1 is required for nymphal moulting and female reproductive success as it plays an important role in regulating 20E synthesis, lipid and chitin metabolisms in N. lugens, thus contributing to our understanding of developmental and reproductive mechanisms in insects.

Soft‐shell crabs are gaining attention internationally as a more lucrative option of selling commercially important portunid species due to their ease of consumption, high nutritional values, and unique and excellent taste. This product, however, is only attainable in captivity as crabs are harvested right after moulting when their exoskeletons are still soft. Among the most crucial factor in soft‐shell crab production is the moult induction method. Shorter moult intervals imply more soft‐shell crabs could be produced, increasing productivity and profit for farmers. This review describes the moulting event, soft‐shell crab production process and production systems, and highlights the currently available and potential moult induction methods, including eyestalk ablation, limb autotomy, the use of ecdysteroid, phytoecdysteroid, biogenic amines and methyl farnesoate, the inhibition of moult‐inhibiting hormone (MIH) and the regulation of physical parameters. This review further compares these moult induction methods and their benefits towards soft‐shell crab production. [ABSTRACT FROM AUTHOR]

Energy metabolism is a critical component in assessing the fundamental aspect of organism fitness in prawn aquaculture farming. This is particularly important to maintain sustainable energy use to cope with stress and tolerance without affecting growth and reproduction functions. This study aims to determine and compare energy utilisation with a special focus on reproductive performance and digestive capacity concerning the handling-stress and moulting cycle of female Giant Freshwater Prawn, Macrobrachium rosenbergii. There were two experimental groups, which are (i) grow-out pond-reared (G1): prawns were sampled randomly and concurrently for one day at an outdoor condition, and (ii) shortterm maintenance (G2): prawns were transported to an indoor hatchery, acclimated for two weeks, and sampled by staggered-method for two consecutive months. For the respective experimental conditions, haemolymph from five females was sampled at eight different moulting stages, whereby each stage was classified as reproductive and non-reproductive moulting cycles. Cultivated females at the grow-out pond had higher levels of haemolymph glucose (P <0.05) at Sub-stages D1 (0.51 ± 0.12 mg/mL), D3 (0.50 ± 0.05 mg/mL), and A (0.71 ± 0.09 mg/mL) during the reproductive moulting cycle compared to the short-term maintenance at similar moulting stages. Other findings showed that cultivated prawns at the grow-out pond had significantly (P <0.05) higher glucose levels at Sub-stages D3 (0.57 ± 0.09 mg/mL) and B (0.37 ± 0.03 mg/mL) during the non-reproductive moulting cycle compared to the short-term maintenance indicating that energy was utilised to cope with the handling stress. We suggest that short-term maintenance may reduce the stressors factor and is applicable for hatchery operations to maintain the health of the prawn. [ABSTRACT FROM AUTHOR]

Ecdysone receptor (EcR) is the primary regulator of the ecdysteroid signalling pathway, a critical pathway that directly links to moulting. In addition, EcR also regulates growth, development, reproduction and regeneration in crustaceans. However, there remains a huge gap of knowledge between the detailed structure and functional role(s) of crustacean EcR compared to that of insects. Motif and phylogenetic analyses of publicly available crustacean EcR proteins revealed the evolutionary relationship of EcR in this subphylum and highlighted its conserved characteristics among crustaceans. The role of EcR in the regulation of essential physiological processes in crustaceans including moulting, chitin synthesis, general growth and development, gonadal and maturation, and limb regeneration was discussed based on the available literature. This essential moult‐related nuclear receptor could serve as a useful molecular indicator of moulting and gonadal maturation, as a potential target for pesticide production against parasitic crustacean species in the aquaculture industry, as well as valuable bioindicators of environmental stressors. [ABSTRACT FROM AUTHOR]

Juvenile hormone epoxide hydrolases (JHEHs) are regulators of moulting, development and metamorphosis in insects, but we have limited understanding of the roles of these crucial hormonal regulator in crustaceans. In this study, the giant freshwater prawn Macrobrachium rosenbergii was used as a model organism to investigate the role of JHEH in larval development and moulting. We cloned and characterized a JHEH gene from M. rosenbergii (designated as MrJHEH). The full‐length cDNA of MrJHEH was 1,682 bp in length, encoding 460 amino acids, and the deduced MrJHEH protein possesses typical features of JHEH family. The phylogenetic analysis revealed that MrJHEH clustered with homologues from crustaceans. Investigation of tissue distribution revealed the abundant expression of MrJHEH in the hepatopancreas. Developmental expression studies showed that the MrJHEH mRNA was expressed throughout the embryo to post‐larval stages, with higher expression at late larval stages. Analysis of the moult cycle showed that the expression of MrJHEH mRNA was significantly elevated at the pre‐moult stage as compared with the inter‐moult level. Both exogenous 20‐hydroxyecdysone (20E) injection and eyestalk ablation (ESA) significantly induced the transcription of MrJHEH in cephalothoraxes. These data suggest that MrJHEH is indispensable for the regulation of larval development and ecdysteroidogenesis of M. rosenbergii. [ABSTRACT FROM AUTHOR]

Chitin deacetylases (CDAs) are essential enzymes during moulting and play vital roles in the formation and modification of chitin. Five chitin deacetylase genes were first identified and characterized in the Chinese mitten crab, Eriocheir sinensis. The spatiotemporal expression profiles of the identified CDAs (EsCDAs) have been investigated to reveal their critical functions in moulting of the Chinese mitten crab. Phylogenetic and structural analysis showed that EsCDAs were divided into four of five groups based on sequence similarity and the multiple groups with diverse domain architectures suggested that there were distinctive biological functions among multi‐gene family of EsCDAs. Each group contained one or more EsCDAs, except group V, and showed different expression patterns in different tissues and developmental stages. EsCDAs were widely distributed in exoskeleton, digestive organs as well as genital organs, and expressed from eggs to juvenile, especially highly in juvenile stage. During the moulting cycle, the expressions of EsCDAs were up‐regulated periodically in the post‐moult stage and enhanced by eyestalk resection, which indicate that EsCDAs play an important role in the formation and modification of chitin. Our present study provides fundamental information about crustaceans in terms of chitin deacetylases involved in the chitin metabolic pathway during moulting. [ABSTRACT FROM AUTHOR]

Arthropods (i.e. insects, spiders, crustaceans, myriapods and others), are the most successful Phanerozoic animals. The group is characterized by the possession of a segmented body, jointed limbs and a hard cuticle that is episodically moulted. One highly successful but now extinct group of arthropods is the trilobites. Trilobites underwent episodic moulting (ecdysis), and most trilobites possess facial sutures, lines of weakness in the cephalon, via which the exuviae is shed and the animal emerges. However, zones of weakness appear to represent a structural trade‐off or constraint, particularly during burrowing; sacrificing a consolidated head region useful in burrowing for the ability to moult. Here we reconcile this trade‐off by using biomechanical modelling to demonstrate that facial sutures exist in regions of low stress during the application of burrowing loads. Furthermore, facial sutures and the structure of the cephalon enable sutured trilobites to withstand greater stresses than their non‐suture counterparts. We suggest that this ability to withstand greater burrowing loads enabled trilobites to successfully invade bioturbated and more consolidated sediments of the Cambrian Sediment Revolution, thus facilitating their diversification in the Cambrian and Ordovician and contributing to the evolutionary success of this iconic arthropod group. [ABSTRACT FROM AUTHOR]

Anthropogenic CO2 emissions to the atmosphere have increased not only air temperature, but also precipitation, which has intensified freshening of the sea surface in some parts of the ocean. As a result, many regions, including the Yellow Sea, have been confronted with a decrease in salinity. In this study we investigated the effects of low salinity on the number of dead individuals and behaviour of Haustorioides koreanus, a gammarid amphipod living in the upper and sandy regions of the tidal flats of the west and south coasts of South Korea. The experiment was conducted over 32 days with four different salinity conditions: 30 (control), 27, 24 and 21 psu (n = 8 each). Although the number of dead individuals, the moulting frequency and burrowing and swimming behaviours of H. koreanus did not significantly differ, the time taken for food detection was increased significantly by low salinity (21 psu). A decrease in the speed of food detection suggests that low salinity can reduce the amphipod’s ability to detect chemical cues. [ABSTRACT FROM AUTHOR]

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In this study, the observations on pre-ecdysis and post-ecdysis during the last ecdysis of Galeodes sp. were recorded. During the ecdysis, a strand-like structure, intracuticular fibre, occurs between the old cuticle and the new one. This intracuticular fibre consists of the tracheal tubes as well as the old cuticle pieces. Thanks to this structure, the solifuge continues its biological activities such as breathing, even at a minimum level, during the quiescence process of the ecdysis. Forming male cheliceral flagellum during the last ecdysis leads to accurate sex determination. [ABSTRACT FROM AUTHOR]

[Display omitted] • Exposure to chlorpyrifos delayed moulting in Armadillo officinalis. • Chlorpyrifos affected the moulting frequency in Armadillo officinalis. • Exposure to chlorpyrifos extended premoult and ecdysis stages in Armadillo officinalis. • Chlorpyrifos reduced intermoult duration in Armadillo officinalis. • Chlorpyrifos impaired growth by decreasing weight gain, cuticle length gain and the specific growth rate of Armadillo officinalis. The aim of this study was to evaluate the long-term effects of the insecticide chlorpyrifos on the moulting and growth of the terrestrial isopods Armadillo officinalis. Adult woodlice were exposed to chlorpyrifos at concentrations of 5, 10, 20, 40 mg/kg dry soil and compared to a control. During 100 days of exposure, effects on moulting and growth were investigated. The duration of premoult, ecdysis and intermoult stages were estimated. Also, the cuticle width (CW) and length (CL) were measured and their size increase and specific growth were calculated. The results showed that exposure to chlorpyrifos induced adverse effects on moulting in the terrestrial isopod Armadillo officinalis , mainly at the higher concentrations (20 mg and 40 mg/kg dry soil). Indeed, it decreased the percentage of moulting animals, delayed moulting, decreased the number of completed moult, extended the premoult stage, prolonged ecdysis, and reduced intermoult duration. Furthermore, these findings showed that chlorpyrifos exposure impaired also growth of Armadillo officinalis, mainly at the highest concentration (40 mg/kg dry soi), by decreasing weight gain (0.94 ± 2.14 mg), cuticle length gain (0.26 ± 0.06 mm) and specific growth rate (SGR) (0.04 ± 0.01 mm/days) compared to the control (Weight gain = 16.5 ± 1.84 mg; CL gain = 0.65 ± 0.07 mm; SGR = 0.08 ± 0.01). The present study highlighted the adverse effects of chlorpyrifos on moulting and growth of Armadillo officinalis, which raises concern about consequences of chlorpyrifos exposure on population dynamic of this species. [ABSTRACT FROM AUTHOR]

The final emergence of the Coromandel Marsh Dart Damselfly Ceriagrion coromandelianum was studied for 50 days (22 January–12 March, 2011) from the botanical garden of Hislop College, Nagpur, India, (a semi controlled site) where small underground cement tubs/tanks are used to grow macrophytes by the Botany department. In C. coromandelianum emergence is asynchronous, diurnal and occurs between 07.00h and 18.00h. Stage-I starts when the ultimate instar nymph of C. coromandelianum leaves the water body, searches for a suitable place and then begins to shudder its body to detach the trapped pharate from the nymphal exuvia. The pharate exerts pressure on the thoracic tergites to split the cuticle. Stage-II starts when the head and thorax of the pharate emerges out of the split exuvia. The pharate struggles to remove its trapped body from the nymphal exuvia. During Stage-III, the wings expand but are opaque; pigmentation of the body occurs simultaneously all over the body. Soon the whole body develops its species specific coloration while the expanding wings gain transparency, unfold and separate out and now the imago is ready for its maiden flight. Stages I, II, and III occupy 31.66%, 11.73%, and 56.60% of the total moulting period, respectively. A total of 243 emergences occurred during the observation period, 158 emergences occurred in tanks containing Pistia stratiotes, while 65 emergences in tubs containing Nymphaea nouchali indicating that C. coromandelianum prefers P. stratiotes over N. nouchali for oviposition. Twenty deaths were recorded during the present observation. Failure to moult (15%) and failure to emerge completely out of the exuvia (85%) were the two reasons for mortality.