Survival Rate Of Larvae Research Articles

Cold-stored mulberry leaves affect antioxidant system and silk proteins of silkworm (Bombyx mori) larva.

Cold storage has been widely used to maintain the quality of vegetables, but whether eating cold-stored vegetables affects health remains unknown. This study used silkworms as an animal model to evaluate the effects of nutrient changes in cold-stored mulberry leaves (CSML) on health. Compared with fresh mulberry leaves (FML), CSML contained lower vitamin C, soluble sugars and proteins, and higher H2 O2 , suggesting decreased antioxidant ability and nutrition. The CSML did not obviously affect larval survival rate, body weight or dry matter rate, cocoon shape, weight and size, or final rates of cluster and cocooning relative to the FML, suggesting CSML did not alter overall growth and development. However, the CSML increased the initial rates of cluster and cocooning and upregulated BmRpd3, suggesting CSML shortened larval lifespan and enhanced senescence. CSML upregulated BmNOX4, downregulated BmCAT, BmSOD and BmGSH-Px and increased H2 O2 in silkworms, suggesting CSML caused oxidative stress. CSML upregulated ecdysone biosynthesis and inactivation genes and elevated ecdysone concentration in silkworms, suggesting that CSML affected hormone homeostasis. CSML upregulated apoptosis-related genes, downregulated sericin and silk fibroin genes and decreased sericin content rate in silkworms, suggesting oxidative stress and protein deficiency. Cold storage reduced nutrition and antioxidant capability of mulberry leaves. CSML did not influence growth and development of silkworm larva, but affected health by causing oxidative stress and reducing protein synthesis. The findings show that the ingredient changes in CSML had negative effects on health of silkworms. © 2023 Society of Chemical Industry.

Effect of marennine on the rearing medium and microbiota of Mytilus edulis larvae and its protective effect after exposure to the pathogenic Vibrio splendidus

ABSTRACT Opportunistic pathogens have been associated with yield-limiting factors in bivalve hatcheries. Numerous natural compounds are being investigated for their beneficial effects and potential to enhance larval resistance without requiring antibiotics. One of those is the use of marennine, a blue pigment, originating from the diatom Haslea ostrearia, which has demonstrated a positive effect on larvae survival. The aim of this study was to highlight the protective effect of marennine on Mytilus edulis larvae during bacterial challenges in relation to a potential modification of the marennine-treated larvae microbiota. D-larvae and post-larvae were exposed for 96 h to Vibrio splendidus (106 cell mL−1) with and without mareninne (500 µg L−1). The presence of marennine increased the survival rate of D-larvae exposed to the pathogen. The molecular analysis of the larvae microbiota diversity indicated a modification in the D-larval microbiota’s richness related to survival rates of larvae. Ultimately, our study sheds light on the importance of the larval microbiota in pathogen resistance during the bivalve rearing process.

EKSTRAKSI BIJI PEPAYA (Carica papaya) SEBAGAI BAHAN AKTIF ANTIBAKTERIAL PADA LARVA UDANG WINDU (Penaeus monodon) SECARA IN VITRO DAN IN VIVO

This research was the administration of papaya seed extract to black tiger prawn which were challenged with Vibrio harveyii infection in vivo and in vitro to determine the effectiveness of papaya seed extract in inhibiting vibrio harveyii. This research was conducted in the laboratory of the Faculty of Fisheries and Marine Sciences, University of Borneo Tarakan in vitro and in vivo. The data obtained were analyzed descriptively and statistically. Based on observations and research it is known that papaya seed extract (Carica papaya) in vitro contains active antibacterial ingredients such as saponins, flavonoids which can inhibit Vibrio in breeding so that it has an impact on the weakness of Vibrio harveyii in disturbing and inhibiting the growth of tiger shrimp larvae during independent research. in vivo. The survival rate of black tiger prawn larvae from the total of each treatment which was maintained for 12 days of treatment showed that the highest value was achieved in treatment P3 of 90% and the lowest was obtained in the negative control treatment of 5%, while in treatment P1 (positive control) of 95 %, P4 was 78% and P2 treatment was 65%.

Preliminary Analysis of Quality and Cryopreservation of Sex-Reversed Female Culter alburnus Sperm

Sex-reversed females are the fathers of all-female fish and their sperm quality directly affects the quality of all-female fish. In this study, fecundity, physiological characteristics, biochemical characteristics, ultrastructure, and viability of sex-reversed female sperm after cryopreservation were investigated to understand sperm quality. (1) The sex-reversed female sperm had a lower fertilization rate, hatching rate, and larval survival rate of 72 hr and higher larval deformation rate compared with normal male sperm. (2) The changes in activation rate between normal male and sex-reversed female sperm under different salinity and pH conditions were the same; the optimum salinity was between 0 and 4%, and the optimum pH was 5.5. (3) The preservation time of sex-reversed female sperm is significantly shorter than that of normal male sperm at room temperature. (4) Sex-reversed female sperm had lower ATPase content and c/p value than normal male sperm. (5) Ultrastructural injury including damaged membranes of the head and mitochondria, broken flagella, greater mitochondrial damage, and mitochondrial membrane expansion were found in the sex-reversed female sperm. (6) The most suitable antifreeze for cryopreservation of sex-reversed female and normal male sperm was 10% ethylene glycol and dilution was D-15, but the activation rate, movement, and life span of sex-reversed female sperm were reduced after cryopreservation. It was speculated that the sperm mitochondria of the sex-reversed female were more damaged than those of the normal male, which led to differences in fertility and cryopreservation.

Effect of temperature on embryonic development and offspring performance of the African river prawn, Macrobrachium vollenhovenii

Macrobrachium vollenhovenii (Herklots, 1857), the largest of the indigenous West African Palaemonidae prawns, has a high potential for aquaculture. This work was carried out to assess the effect of temperature on embryonic development and offspring quality of this species. In the phase one experiment, females at stage V of gonadal development incubated their eggs at three experimental temperatures and their embryonic development was evaluated. Seven embryonic developmental stages were observed: fertilisation, mitosis, morula, blastula, gastrula, nauplius and larvae. The incubation periods were 19, 14 and 13 days at 26 °C, 28 °C and 30 °C, respectively. A temperature of 30 °C resulted in higher broodstock mortality (33.33%). In phase two, larvae were reared at the respective temperatures for 30 days at a stocking density of 30 larvae per litre of water. Offspring quality was significantly different between treatments from day five onwards, with the fastest development at 30 °C followed by 28 °C. However, larval survival rate was significantly higher at 26 °C (31.7%) followed by 28 °C (27.6%). A temperature of 28 °C could therefore be recommended as the most favourable for embryonic development and larviculture of M. vollenhovenii. These findings will help bridge the knowledge gap with respect to captive breeding and hatchery technology for M. vollenhovenii.

Zoea Crab Larva Counter (CLARCO) Based On Image Processing With Adaptive Gaussian Filter Algorithm And Blob Detection Technique

The size of crab larvae is very small, so there is no accurate and easy-to-use crab larvae counting tool at an affordable price. The low larval survival rate is due to the unknown larval stocking density, which causes cannibalism, a feed-to-larvae ratio that is out of proportion to the number of larvae needed to maintain water quality, a water supply that is out of proportion to stocking density, and is economically unfavorable in terms of cultivation, feed management, maintaining water quality, and the buying and selling process. Accurately estimating the amount of crab larvae is anticipated to boost their survival rate and make them more economically successful. This research is a continuation of previous research with the addition of different methods using adaptive gaussian filter algorithms and blob detection techniques to count crab larvae in the zoea-2, zoea-3, and zoea-4 phases where an increase in accuracy was obtained with an average of 97.67%.

Effects of Different Feeding Regimes on Growth Performance, Survival Rate, Carcass Composition, Fatty Acids Profile, and Digestive Enzyme Activities of Great Sturgeon (Huso huso Linnaeus, 1758) Larvae

Six different feeding regimes (FR) were tested from 7 to 38 days post hatching (dph). Five thousand four hundred larvae (7 dph, 0.048 g) were randomly stocked in 18 fiberglass tanks contained 100 L fresh water (300 larvae per each tank). In larvae fed with FR-B, includes Artemia nauplii (AN) + Artemia biomass (AB) + microdiet (MD), the body weight (BW) at the end of trail (38 dph) similar the FR-D (AN + CHL + AB + MD), and E (AN + CHL + AB), was at high level. Survival rate was higher in larvae fed FR-A includes AN + chironomid larvae (CHL) + MD, but had a lower BW ( p < 0.05 ). Moderate BW and survival rate were detected in larvae fed FR-C (AN + DP + MD). Larvae fed only MD (FR-F), had the lowest survival and the highest BW ( p < 0.05 ). Different FR had a significant effect on crude protein (CP), crude fat (CF), ash, and dry weight ( p < 0.05 ). The larvae fed FR-C and D had the highest CP ( p < 0.05 ). The highest CF and ash in larvae were detected in FR-F and C, respectively ( p < 0.05 ). Larvae from FR-A and B had higher levels of n−3 long chain polyunsaturated fatty acids in comparison with others FR ( p < 0.05 ). The use of AB and CHL can increased the weight and survival rate of larvae, respectively. At the end of trail, the activity of pepsin, trypsin, lipase and α-amylase enzyme levels were lower in FR-B and F than others FR. Totally, by using a combination of AN + CHL + AB + MD had better results than others and ordered to H. huso larvae feeding. Using MD alone, can cause lesser development of the digestive system and little attractiveness, therefore it can cause starvation, and the empty digestive tract of larvae.

A novel technique for mass induction of propagation in small fish species: Hormone immersion

Due to the lack of environmental stimuli found in their natural habitat, not all species of tiny fish can reproduce naturally in the conditions of captivity. Silver rasbora (Rasbora argyrotaenia) was used as the model organism in this study, which is the first to successfully use the hormonal technique of immersion to mass induce spawning and spermiation in small fish species. In this study, in order to find out the effect of immersion hormone treatment, two separate experiments in which commercial hormone Ovaprim™ was used for spawning induction and Ovagold™ for spermiation induction were conducted. Four doses of hormones (0.0 mL/L, 0.7 mL/L, 1.4 mL/L, and 2.1 mL/L) were evaluated on 24 females and 40 males in total. According to the experimental findings of female breeders, 1.4 mL/L dose of Ovaprim™ showed best results on latency period (8.67 h) with a total number of eggs (6994 egg) and fertilization rate (99.22 %). In addition, hatching and larval survival rate have also increased. Milt volume and sperm concentration have also seen an increase to 4.25 μL/g bw and 42.71 106 cell/μL respectively at 2.1 mL/L hormone concentration. The best results or responses were obtained by immersion treatments using Ovaprim™ doses of 1.4 mL/L on female and Ovagold™ concentrations of 2.1 mL/L on male. This new technique is a beneficial for breeding small fish species for either commercial or conservational culture condition.

A Protein Asteroid with PIN Domain in Silkworm Bombyx mori Is Involved in Anti-BmNPV Infection

Nuclease is a type of protein that degrades nucleic acids, which plays an important role in biological processes, including RNA interference efficiency and antiviral immunity. However, no evidence of a link between nuclease and Bombyx mori nucleopolyhedrovirus (BmNPV) infection in silkworm B. mori has been found. In this study, a protein asteroid (BmAst) containing the PIN domain and XPG domain was identified in silkworm B. mori. BmAst gene was highest expressed in hemocytes and fat body of the 5th instar larvae, and high expression in the pupa stage. The transcriptional levels of the BmAst gene in 5th instar larvae were significantly induced by BmNPV or dsRNA. After knocking down BmAst gene expression by specific dsRNA, the proliferation of BmNPV in B. mori was increased significantly, whereas the survival rate of larvae was significantly lower when compared with the control. Our findings indicate that BmAst is involved in silkworm resistance to BmNPV infection.

Validation of the Use of Otoliths to Estimate Age and Growth of Larval Lake Whitefish, Coregonus clupeaformis

Understanding drivers of recruitment variation in fish populations requires research conducted on early life stages. Examination of fish otoliths provides useful information for estimating hatching dates, growth, and survival rates of larvae and for investigating the relationship between early life stage phenology and variation in environmental factors such as climate and food availability. In the Laurentian (i.e., North American) Great Lakes, significant reductions in the number of young (ages 1–4 years) lake whitefish (Coregonus clupeaformis) recruiting into the population and commercial fishery have raised questions about factors affecting growth and survival of the larval life stage. Here, we investigate the utility of using otoliths to estimate the age and growth of larval lake whitefish. We raised offspring of wild-caught parents from Lake Simcoe (Ontario, Canada) in a hatchery environment and analyzed otoliths of these known age fish for 75 days posthatch. We further examined otoliths of wild-sampled larvae and age 0 lake whitefish from Lake Huron. We found a strong linear relationship between known age and number of postcheck increments on the otolith and between growth of the otolith and fish length. Increments formed at nearly 1 (0.9) per day beginning at day 20 after hatch. Check and subsequent increment formation was associated with disappearance of the yolk sac. Wild fish had more prominent checkmarks and grew slower than hatchery fish. Thus, otolith analysis represents a promising tool to examine dynamics of early life stages of lake whitefish, although further research is required on the effects of environmental conditions on otolith microstructure.

A gut-isolated Enterococcus strain (HcM7) triggers the expression of antimicrobial peptides that aid resistance to nucleopolyhedrovirus infection of Hyphantria cunea larvae.

Commensal microorganisms are widely distributed in insect gut tissues and play important roles in to host nutrition, metabolism, reproductive regulation and, especially the immune functioning and tolerance to pathogens. Consequently, gut microbiota represent a promising resource for the development of microbial-based products for pest control and management. However, the interactions among host immunity, entomopathogen infections, and gut microbiota remain poorly understood for many arthropod pests. We previously isolated an Enterococcus strain (HcM7) from Hyphantria cunea larvae guts that increased the survival rates of larvae challenged with nucleopolyhedrovirus (NPV). Here, we further investigated whether this Enterococcus strain stimulates a protective immune response against NPV proliferation. Infection bioassays demonstrated that the re-introduction of the HcM7 strain to germ-free larvae pre-activated the expression of several antimicrobial peptides (particularly H. cunea gloverin 1, HcGlv1), resulting in the significant repression of virus replication in host guts and hemolymph, and consequently improved host survivorship after NPV infection. Furthermore, silencing of the HcGlv1 gene by RNA interference markedly enhanced the deleterious effects of NPV infection, revealing a role of this gut symbiont-induced gene in host defenses against pathogenic infections. These results show that some gut microorganisms can stimulate host immune systems, thereby contributing to resistance to entomopathogens. Furthermore, HcM7, as a functional symbiotic bacteria of H. cunea larvae, may be a potential target for increasing the effectiveness of biocontrol agents against this devastating pest.

Dietary effects on larval survival and development of three sesarmid crabs

Semi-terrestrial brachyuran sesarmid crabs are the most diverse and important faunal components of mangrove forest and temperate coastal communities worldwide. To establish a stable larval rearing method for understanding their larval developmental processes including molecular mechanisms of molting and metamorphosis, we examined the effects of diet on the survival and growth of three sesarmid crabs, Chiromantes haematocheir, Orisarma intermedium, and O. dehaani under larval development. Zoea of each species, immediately after hatching, were reared under different feeding conditions as follows: non-feeding; fed only nutrition-enriched rotifers; fed only Artemia (brine shrimp) nauplii; and fed a combination of both nutrition-enriched rotifers and brine shrimp. Larvae of each species survived almost to megalopa when they were fed both rotifer and brine shrimp, but all C. haematocheir larvae had died by zoeal stage 2 when they were only fed brine shrimp. Chiromantes haematocheir larvae could survive into the megalopa stage when fed only nutrition-enriched rotifer, whereas both O. dehaani and O. intermedium showed 50% or less survival and metamorphosis rates into megalopa. The duration of larval development and survival rates of the three crabs were shorter and higher, respectively, in the mixed feeding group (both rotifer and brine shrimp) than when only fed rotifer or brine shrimp. This study provides baseline knowledge of the interspecific variability in larval survival and duration under different diets for sympatric sesarmid crab species.

Successful application of UV-irradiated rainbow trout (Oncorhynchus mykiss) spermatozoa to induce gynogenetic development of the European grayling (Thymallus thymallus)

In fish with the XX/XY sex determination system, the production of all-female offspring within one generation was achieved by gynogenesis. Successful induction of gynogenesis in the European grayling (Thymallus thymallus) (Salmonidae) included egg activation with UV-irradiated homologous (996 J/m2) and heterologous (rainbow trout) sperm (1370 J/m2) followed by exposure of the inseminated eggs to a high hydrostatic pressure (HHP) shock (9000 psi for 5 min) 20 min after their activation. The survival rates of the gynogenotic larvae at the swim-up stage exhibited a huge inter-clutch variability that ranged from 1.12 ± 0.53% to 14.15 ± 1.27% and from 0.96 ± 0.33% to 60.57 ± 1.85% when the eggs were activated by UV-irradiated homologous and heterologous sperm, respectively. Maternal inheritance was only confirmed in the gynogenotes that hatched from eggs inseminated by inactivated heterologous sperm, whereas an admixture of the paternal DNA was detected among screened individuals that originated from eggs activated by homologous sperm. All the examined gynogenotes produced using heterologous sperm were confirmed to be genetically females. In the case of fish with an admixture of the paternal DNA, male genotypes and phenotypes were observed. One of the genetic males had well developed testes. Differences in the ratio of deformed larvae that hatched from eggs activated by UV-irradiated homologous and heterologous sperm were nonsignificant. Based on the obtained results, it has to be stated that the activation of grayling eggs with UV-irradiated rainbow trout sperm followed by HHP shock is a reliable and fast method for the production of all-female grayling stocks.

Toxicity of (S)-(-)-palasonin on various life stages of Plutella xylostella (Lepidoptera: Plutellidae)

Plutella xylostella has developed resistance to most commercially available insecticides, resulting in an urgent need for novel insecticides. It was found in our previous study that (S)-(-)-palasonin (PLN) has great value in the management of P. xylostella. Extracted from Butea monosperma seeds, (S)-(-)-palasonin has been discovered to have stomach and contact toxicity against P. xylostella larvae. However, it is not clear whether PLN has other modes of action. In this study, (S)-(-)-palasonin had strong stomach and fumigation activity against P. xylostella adults with an LC50 (48 h) values of 50.50 and 16.49 mg/L, respectively. The selective antifeedant rate and non-selective antifeedant rate of (S)-(-)-palasonin at 25 mg/L were 92.86 % and 97.27 % respectively. Normal growth and development of P. xylostella larvae was inhibited by (S)-(-)-palasonin. The larval weight and weight gain were significantly inhibited, the relative growth inhibition rate was increased, and the instar stage was significantly prolonged. The larval survival rate, pupal weight, pupation rate and adult emergence rates were significantly reduced. Wing deformity in P. xylostella adults was observed. And the life span of adults was shortened. These results show that (S)-(-)-palasonin has various modes of action in P. xylostella and can be used as a potential new botanical insecticide for the control of P. xylostella.

Embryo and larvae development of Nilem Fish, Osteochilus vittatus reared in batik liquid waste

Abstract. Nugrahesthi GH, Wijayanti GE, Habibah AN. 2023. Embryo and larvae development of Nilem Fish, Osteochilus vittatus reared in batik liquid waste. Nusantara Bioscience 15: 105-112. The embryonic and larval stages are critical phases of an organism's development. For aquatic organisms, development is affected by environmental factors such as liquid waste. A batik liquid waste is a waste product of the textile industry usually streamed directly into the aquatic environment. This study aimed to observe the effects of exposure to batik liquid waste effects on developing Nilem (Osteochilus vittatus Valenciennes, 1842) fish embryos and larvae. The research was conducted using a completely randomized design. One hundred two-celled embryos were kept in batik liquid waste with dilution concentrations of 0% (the control), 5%, 10%, 15%, and 20% of water until the age of 4 days after hatching with five replications. The time of embryo evaluation was 60th minutes, 120th minutes, and 180th minutes after fertilization; the larval stage evaluation time was the 24th, 48th, 72nd, and 96th hour after fertilization; five embryos were evaluated for each replication. The results showed that embryo exposure to batik liquid waste affected the height of the blastoderm embryo, accumulation of waste in the chorion of the embryo, deceleration of embryonic development, increased larval abnormalities, decreased the survival rate of larvae, and acceleration of yolk absorption of fish larvae. Embryos were successfully hatched and produced larvae only in the control and 5% batik liquid waste medium. Batik liquid waste interfered with O. vittatus embryo development and generated mortality above 5%.

Microbial biomarker detection in shrimp larvae rearing water as putative bio-surveillance proxies in shrimp aquaculture.

Aquacultured animals are reared in water hosting various microorganisms with which they are in close relationships during their whole lifecycle as some of these microorganisms can be involved in their host's health or physiology. In aquaculture hatcheries, understanding the interactions existing between the natural seawater microbiota, the rearing water microbiota, the larval stage and the larval health status, may allow the establishment of microbial proxies to monitor the rearing ecosystems. Indeed, these proxies could help to define the optimal microbiota for shrimp larval development and could ultimately help microbial management. In this context, we monitored the daily composition of the active microbiota of the rearing water in a hatchery of the Pacific blue shrimp Penaeus stylirostris. Two distinct rearing conditions were analyzed; one with antibiotics added to the rearing water and one without antibiotics. During this rearing, healthy larvae with a high survival rate and unhealthy larvae with a high mortality rate were observed. Using HiSeq sequencing of the V4 region of the 16S rRNA gene of the water microbiota, coupled with zootechnical and statistical analysis, we aimed to distinguish the microbial taxa related to high mortality rates at a given larval stage. We highlight that the active microbiota of the rearing water is highly dynamic whatever the larval survival rate. A clear distinction of the microbial composition is shown between the water harboring heathy larvae reared with antibiotics versus the unhealthy larvae reared without antibiotics. However, it is hard to untangle the effects of the antibiotic addition and of the larval death on the active microbiota of the rearing water. Various active taxa of the rearing water are specific to a given larval stage and survival rate except for the zoea with a good survival rate. Comparing these communities to those of the lagoon, it appears that many taxa were originally detected in the natural seawater. This highlights the great importance of the microbial composition of the lagoon on the rearing water microbiota. Considering the larval stage and larval survival we highlight that several genera: Nautella, Leisingera, Ruegerira, Alconivorax, Marinobacter and Tenacibaculum, could be beneficial for the larval survival and may, in the rearing water, overcome the r-strategist microorganisms and/or putative pathogens. Members of these genera might also act as probiotics for the larvae. Marivita, Aestuariicocccus, HIMB11 and Nioella, appeared to be unfavorable for the larval survival and could be associated with upcoming and occurring larval mortalities. All these specific biomarkers of healthy or unhealthy larvae, could be used as early routine detection proxies in the natural seawater and then during the first days of larval rearing, and might help to manage the rearing water microbiota and to select beneficial microorganisms for the larvae.

Дирофиляриоз витреальной полости

Relevance. Dirofilariasis (Dirofilariasis, from Lat. «diro, filum» – «evil thread») is a disease that belongs to the group of transmissible zoonotic biohelminthiasis. Man is the facultative host of dirofilariae. That is why the survival rate of larvae in the human body is very low. Up to 50% of cases of dirofilariasis registered in humans are due to dirofilariasis of the visual organs. The intraocular form is extremely rare. The true incidence of dirofilariasis in humans is unknown, due to the fact that there is no official registration. Dirofilariae widely circulates in the natural environment, but at the moment there are no systematic measures to identify and deworming infected animals. In addition, due to insufficient awareness of doctors working in the practical healthcare system, this pathology is often detected and treated under various diagnoses of non-parasitic etiology. Purpose. To present a clinical case of a method of surgical removal of dirofilariasis in the vitreal cavity. Material and methods. The article presents a rare clinical case of intraocular invasion of dirafilariasis, and also describes the surgical tactics of helminth extraction. Results and discussion. The patient underwent surgical treatment in the volume of vitrectomy with the removal of the parasite with positive functional results. Surgical intervention is a radical and the only possible treatment in the case of intraocular invasion of dirofilaria. Conclusion. It is important to understand that localization of dirofilaria in the vitreous cavity, without radical surgical treatment, can lead to threatening consequences of vision loss. And the increase in the frequency of cases of dirofilariasis indicates the need for doctors to be wary of the differential diagnostic approach in identifying pathologies. Key words: dirofilaria, helminthiasis, vitreoretinal surgery, vitreous, intraocular invasion

NSD Overexpression in the Fat Body Increases Antimicrobial Peptide Production by the Immune Deficiency Pathway in Drosophila.

Nuclear receptor-binding SET domain-containing protein 1 (NSD1) inactivation in tumor cells contributes to an immune-cold phenotype, indicating its potential association with immune disturbances. Drosophila NSD is a homolog of the human NSD1. Thus, in this study, we investigated the effect of NSD overexpression in the fat body, the central organ involved in Drosophila immune responses. Upon ectopic expression of NSD in the fat body, the mRNA levels of antimicrobial peptides increased. Using reporter constructs containing deletions of various NF-κB sites in the Attacin-A (AttA) promoter, we found that transcriptional activation by NSD is mainly mediated via the IMD pathway by activating Relish. Since the IMD pathway is required to resist Gram-negative bacterial infections, we further examined the effect of fat body-specific NSD overexpression on Drosophila immune defenses. Upon oral ingestion of Gram-negative Pseudomonas entomophila, the survival rate of the NSD-overexpressing larvae was higher than that of the wild type, suggesting a positive role of NSD in immune responses. Taken together, these results suggest the association of NSD with the IMD pathway and is thus expected to contribute to the elucidation of the molecular mechanisms of immune malfunction in various NSD1-associated human diseases.

Effect of Host-Associated Bacillus-Supplemented Artificial Diets on Growth, Survival Rate, and Gene Expression in Early-Stage Eel Larvae (Anguilla japonica)

Beneficial microorganisms can increase nutrient digestion and absorption in farmed fish. This study investigates the effects of supplemental feeding of Bacillus species isolated from the intestines of wild glass eels on the growth, survival, and gene expression of farm-raised eel larvae for 30 days after hatching. Three species of Bacillus (B. velezensis, AJBV; B. subtilis, AJBS; B. licheniformis, AJBL) without hemolytic activity were isolated, and an experiment compared the growth of eel larvae fed an artificial diet supplemented with each Bacillus species. There were no significant differences in the total length and body depth of eel larvae at 30 days after hatching in all groups. During the feeding period, 149 eels survived from the initial 1000 in the control group. On the other hand, 240, 178, and 141 eels survived in the AJBV, AJBS, and AJBL groups, respectively. However, there were no significant differences in survival rates despite the difference in the number of surviving eel larvae among the groups. In the comparison of gene expression of genes involved with growth (growth hormone, growth hormone receptor 1, insulin-like growth factor II-2) and those involved with digestive enzymes (amylase, trypsin, lipase), there were also no significant differences among the groups. Our results confirm that dietary supplementation with each of the three host-associated Bacillus does not affect the growth and survival rates of eel larvae reared on an artificial diet up to the first 30 days after hatching, nor does it significantly affect related gene expression.

Effects of temperature on Anisakis simplex sensu stricto L3 larvae experimentally challenged in rainbow trout (Oncorhynchus mykiss) and Mozambique tilapia (Oreochromis mossambicus)

Human anisakiasis is a foodborne disease that has been increasingly reported worldwide and is caused by the consumption of raw or undercooked seafood infected with zoonotic nematodes of the genus Anisakis Dujardin, 1845. One of the most frequently reported species, both in fish paratenic hosts as well as in human patients, is Anisakis simplex sensu stricto (s.s.), which is distributed within some of the globe's main fishing grounds in the North Pacific and Atlantic oceans. In order to clarify the influence of temperature on this parasite in vivo, third-stage larvae of A. simplex s.s. were surgically challenged in the body cavities of rainbow trouts (Oncorhynchus mykiss) and Mozambique tilapias (Oreochromis mossambicus). Larval survival and tissue migration were then analyzed after 6 and 12weeks. The results showed that survival rates of larvae were lower at 27 and 33°C than at 3, 9, 15 and 21°C. Also, migration to the body muscle was observed to be highest at 9°C. These results suggest that third-stage larvae of A. simplex s.s. are more adapted to lower temperatures in experimentally challenged fish, which may justify its distribution in cold northern waters.