Effects of four types of natural bait on water quality, feeding, growth, and antioxidant enzyme activity of Monopterus albus in a recirculating aquaculture system.

Monopterus albus is one of China's renowned and superior aquaculture species, with its seedlings mainly sourced from wild capture. One of the bottlenecks in M. albus aquaculture is the high mortality rate and low feeding initiation rate from stocking wild fry to the initiation of feeding. In production, trash fish is commonly used to wean M. albus juveniles onto feeding. In this study, we introduced three other natural feeds, earthworms (EW), yellow mealworms (YMW), and fly maggots (FM), with frozen trash fish (TF) serving as the control group, to evaluate the effects of these four natural feeds on the survival rate, feeding initiation, antioxidant enzymes activity, and body composition of M. albus juveniles under recirculating water aquaculture conditions. The experiment comprised four treatments, each with three replicates. Each replicate consisted of stocking 150 M. albus juveniles weighing 10.02 ± 0.89 g in size, raised for 5 weeks. The survival rate of the YMW group was 73.33%-85.33%, which was significantly higher than that of the other three bait groups (p < 0.05). The four bait groups showed no significant differences in final body weight and specific growth rate (SGR) (p > 0.05). The EW group showed the highest final body weight, with an average SGR of 2.73, whereas the YMW group had an average SGR of 1.87. The average daily feeding amount was significantly higher in EW and YMW groups than in the other two groups (p < 0.05). The percentage of feeding amount to fish weight in the EW group reached 7.3% in the fifth week. After 5 weeks of cultivation, NO2 --N content was significantly higher in the waters of the TF and EW groups than in the waters of the FM and YMW groups (p < 0.05), there was no significant difference in TAN content among the treatment groups (p > 0.05). Liver malondialdehyde content was significantly higher in the TF group than in the other bait groups (p < 0.05). GSH-Px activity was significantly higher in the EW group than in the FM group and YMW group. No significant differences in SOD and CAT activity and T-AOC were observed among the bait groups (p > 0.05). The increase in crude protein content was significantly higher in the TF group than in the FM group, but the increase in crude ash content was significantly lower in the TFgroup. In conclusion, Tenebrio molitor could potentially serve as one of the alternative feeds during the initial stages of M. albus juveniles stocking.

Comparative studies on the intestinal health of wild and cultured ricefield eel (Monopterus albus).

Fish intestinal health under intensive aquaculture mode plays an important role in growth, development, and immune function. The present study was aimed to systematically investigate the differences of intestinal health between wild and cultured Monopterus albus by biochemical parameters, histomorphology, and molecular biology. A total of 15 healthy M. albus per group, with an average body weight of 45 g, were sampled to analyze intestinal health parameters. Compared with wild fish, the cultured M. albus in the foregut had lower trypsin, lipase, SOD, CAT, T-AOC, and GSH-Px activities (P < 0.05) and higher amylase activity and MDA content (P < 0.05). The villus circumference and goblet cells in the cultured group were significantly lower than those in the wild group (P < 0.05). In addition, the cultured fish showed lower relative expression levels of occludin, zo-1, zo-2, claudin-12, claudin-15, mucin5, mucin15, lysozyme, complement 3, il-10, tgf-ß1, tgf-ß2, and tgf-ß3 (P < 0.05) and higher il-1ß, il-6, il-8, tnf-a, and ifnγ mRNA expressions than those of wild fish (P < 0.05). In terms of gut microbiota, the cultured group at the phylum level displayed higher percentages of Chlamydiae and Spirochaetes and lower percentages of Firmicutes, Bacteroidetes, Actinobacteria, Cyanobacteria, and Verrucomicrobia compared to the wild group (P < 0.05). At the genus level, higher abundances of Pseudomonadaceae_Pseudomonas and Spironema and lower abundances of Lactococcus and Cetobacterium were observed in the cultured group than in the wild group (P < 0.05). To our knowledge, this is the first investigation of the intestinal health status between wild and cultured M. albus in terms of biochemistry, histology, and molecular biology levels. Overall, the present study showed significant differences in intestinal health between wild and cultured M. albus and the main manifestations that wild M. albus had higher intestinal digestion, antioxidant capacity, and intestinal barrier functions than cultured M. albus. These results would provide theoretical basis for the subsequent upgrading of healthy aquaculture technology and nutrient regulation of intestinal health of cultured M. albus.

Biochemical, Histological, and Transcriptomic Analyses Reveal Underlying Differences in Flesh Quality between Wild and Farmed Ricefield Eel (Monopterus albus).

The present study aimed to systematically investigate the underlying differences in flesh quality between wild and farmed Monopterus albus. Fifteen healthy M. albus per group with an average body weight of 45 g were sampled to analyze muscle parameters by biochemical indicators, histomorphology, and molecular biology. Compared with the wild fish, the farmed M. albus in flesh had lower crude protein, collagen, lysine, histidine, total amino acids, SFA, n-3 PUFA contents, and n-3/n-6 ratio (p < 0.05), and higher moisture, crude lipid, crude ash, MUFA, n-6PUFA, and total PUFA contents (p < 0.05). The thawing loss, drip loss, steaming loss, and boiling loss in the farmed group were significantly higher, and hardness, springiness, cohesiveness, gumminess, chewiness, and resilience were significantly lower than those in the wild group (p < 0.05). In addition, higher muscle fiber density and lower muscle fiber diameter were observed in wild M. albus (p < 0.05). In muscle transcriptome profiling, differentially expressed genes and enriched pathways are primarily associated with muscle development, protein synthesis, catabolism, lipid metabolism, and immunity. To the best of our knowledge, this is the first investigation that compares the flesh quality between wild and farmed M. albus in terms of biochemistry, histology, and molecular biology levels. Overall, wild M. albus had a higher nutritional value and texture quality than farmed M. albus.

Effects of dietary melatonin supplementation on growth performance and intestinal health of rice field eel (Monopterus albus).

The objective was to assess the impact of melatonin supplementation on the growth performance and intestinal health of rice field eel, Monopterus albus. Three hundred and sixty fish (28.46 ± 0.24 g) were fed five diets supplemented with melatonin of 0, 30, 60, 120, and 240 mg/kg for 70 days. The study found that the variables FBW, WGR, SGR, and FCR exhibited a statistically significant quadratic relationship (P < 0.05) with the dietary melatonin concentrations, and the highest FBW, WGR and SGR as well as lowest FCR were observed in the 120 mg/kg melatonin group, digestive enzymes activities (such as amylase, trypsin, and lipase) also had significant quadratic relationship (P < 0.05), and the highest intestinal villus height and goblet cells were found in the 120 mg/kg diet (P < 0.01), melatonin in diets significantly increased SOD and CAT activities in serum, up-regulated the expression of anti-inflammatory factors (IL-10) and tight junction protein (ZO-1), and down-regulated the expression of pro-inflammatory factors (IL-1ß, IL-8, IL-15, and TNF-α) in the gut, dietary melatonin improved the intestinal microflora compositions, in the group that supplementation a dosage of 120 mg/kg, there was a noticeable rise in the abundance of Firmicutes and the ratio of Firmicutes/Bacteroidota, compared with control group (P < 0.1). Conclusively, dietary supplementation of melatonin promoted growth performance, enhanced intestinal immune capacity and serum antioxidant level, and improved intestinal morphology properties and intestinal flora composition in M. albus. In conclusion, based on quadratic broken-line regression analysis of WGR and FCR, the optimal concentration of melatonin to be supplied is predicted to be 146-148 mg/kg.

Effects on growth performance and immunity of Monopterus albus after high temperature stress.

To investigate the impact of the effect of high temperature stimulation on Monopterus albus larvae after a certain period of time, five experimental groups were established at different temperatures. Then, the M. albus under high temperature stress was fed at 30°C for 70 days. After that, the growth index of the M. albus was counted and analyzed. In terms of growth index, high temperature stress had significant effects on FCR, FBW, WGR, and SGR of M. albus (p < 0.05). The SR increased after being stimulated by temperature (p < 0.1). The study revealed that liver cells of M. albus were harmed by elevated temperatures of 36°C and 38°C. In the experimental group, the activities of digestive enzymes changed in the same trend, reaching the highest point in the 32°C group and then decreasing, and the AMS activity in the 38°C group was significantly different from that in the 30°C group (p < 0.05). The activities of antioxidase in liver reached the highest at 34°C, which was significantly different from those at 30°C (p < 0.05). In addition, the expression levels of TLR1, C3, TNF-α, and other genes increased in the experimental group, reaching the highest point at 34°C, and the expression level of the IL-1ß gene reached the highest point at 32°C, which was significantly different from that at 30°C (p < 0.05). However, the expression level of the IRAK3 gene decreased in the experimental group and reached its lowest point at 34°C (p < 0.05). The expression level of the HSP90α gene increased with the highest temperature stimulus and reached its highest point at 38°C (p < 0.05). In the α diversity index of intestinal microorganisms in the experimental group, the observed species, Shannon, and Chao1 indexes in the 34°C group were the highest (p < 0.05), and ß diversity analysis revealed that the intestinal microbial community in the experimental group was separated after high temperature stimulation. At the phylum level, the three dominant flora are Proteus, Firmicutes, and Bacteroides. Bacteroides and Macrococcus abundance increased at the genus level, but Vibrio and Aeromonas abundance decreased. To sum up, appropriate high-temperature stress can enhance the immunity and adaptability of M. albus. These results show that the high temperature stimulation of 32°C-34°C is beneficial to the industrial culture of M. albus.

Genetic Diversity Analysis of the Red Swamp Crayfish Procambarus clarkii in Three Cultured Populations Based on Microsatellite Markers.

With the increasing scale of crayfish breeding, the self-propagation and "catch large and keep small" breeding patterns have led to serious degradation of the fry, so the selection and breeding of high-quality fry is very important. Selecting a population with a high genetic diversity as the base population for breeding can greatly improve the breeding efficiency. Fifteen microsatellite loci were used to understand the genetic structure and diversity of three Procambarus clarkii populations in Chongming, Shanghai; Gaoyou, Jiangsu; and Xuancheng, Anhui. The results indicated that the three populations were diverse and the number of alleles, observed heterozygosity, expected heterozygosity, Shannon information index, and polymorphic information content ranged from 4.8 to 6.2, 0.5567 to 0.6257, 0.6166 to 0.7086, 1.1292 to 1.3987, and 0.5446 to 0.6452, respectively. The Xuancheng population had the highest genetic diversity. The genetic differentiation coefficient and gene flow of the three populations were between 0.0553 and 0.1068 and 2.0908 and 4.2708, respectively, and there was extensive genetic exchange between the Chongming and Xuancheng populations. Analyses of molecular variance indicated that the genetic variation was mainly within the population (91.51%) and inter-population genetic variation accounted for 8.49%. The unweighted pair group method with an arithmetic mean clustering map was utilised based on the genetic distance between groups, and the results showed that the Gaoyou group was grouped alone, while the Chongming and Xuancheng groups were clustered together. The structural results indicated that the Chongming and Xuancheng groups had the same origin, although the Xuancheng group possessed a more complex genetic structure. This study indicated that all three populations had a high genetic diversity, with the Xuancheng population exhibiting the highest diversity. The results of the study provide a reference for the selection of base populations in breeding programs and confirm that the Xuancheng population in Anhui has a better genetic background. The selection of the Xuancheng population as one of the base populations for genetic breeding will be more efficient to accumulate superior traits.

Effect of different rice transplanting patterns on microbial community in water, sediment, and Procambarus clarkii intestine in rice-crayfish system.

Although the microbial ecology of integrated rice-crayfish farming systems is receiving increasing attention with the expanding application area in China, the effects of rice transplanting patterns on the microbial community of water, sediment and Procambarus clarkii intestine in rice-crayfish system has yet to be determined. This study explored the microbial community present in water, sediment and intestine samples from three transplant patterns (rice crayfish with wide-narrow row transplanting, rice-crayfish with normal transplanting and pond-crayfish, abbreviated as RC-W, RC, and PC, respectively) using high-throughput sequencing. The results showed that the dominant microbial taxa from sediment, surrounding water, and intestine at phylum level were Proteobacteria, Chloroflexi, Cyanobacteria, Actinobacteria, Bacteroidetes. The patterns of rice transplanting had significant effects on microbial biodiversity and species composition in surrounding water. The OTUs community richness of water under RC group was significantly higher than that of PC group and RC-W group. The OTU relative abundance of top 10 operational taxonomic units had significantly different (p < 0.05) in the water samples from the three groups. The intestinal OTU community richness of Procambarus clarkii in the three groups was positively correlated with the community richness of water. The proximity between intestinal and water samples in PCA diagram indicated that their species composition was more similar. The results also showed that rice transplanting patterns can affect intestinal microbial biodiversity of Procambarus clarkii and the intestinal microbial biodiversity correlated with water bodies. Although the intestinal microbial diversity of crayfish in RC-W group was lower than that in RC group, the relative abundance of potential pathogenic bacteria, such as Vibrio, Aeromonas, in intestine of the crayfish in the RC-W group was significantly decreased under rice wide-narrow row transplanting model. Redundancy analysis revealed that environmental parameters, such as pH, DO, nitrate, which regulate the composition of microbial community structures. This study provides an understanding for microbial response to different rice transplanting pattern in rice-crayfish farming system.

Effect of Sodium Tanshinoneâ ¡A Sulfonate on Uric Acid, Sicam-1, ET-1 and FMD in Patients with Coronary Heart Disease Complicated with Hyperuricemia.

This study was to observe the effect of Sodium TanshinoneⅡA Sulfonate (ST-ⅡAS) on blood uric acid (UA), human Soluble Intercellular Adhesion Molecule-1 (sICAM-1), Endothelin-1 (ET-1) and percentage of brachial artery Flow-Mediated Dilatation (FMD) in individuals with Hyperuricemia Complicated Coronary Heart Disease (HC-CHD). The study's participants were 108 patients with HC-CHD who attended our hospital between January 2020 and June 2022. In the trial, the patients were split into two groups with 54 instances each: the general group and the observation group. The observation group received ST-IIAS therapy, while the general group received standard care. The experiment chose to observe and compare the difference of uric acid, sICAM-1, ET-1, FMD, therapeutic effectiveness and negative effects between the two groups at various times. Results showed that on the 14th day, the observation group's amounts of UA, sICAM-1, and ET-1 were inferior to the general group (P<0.05); On the 7th and 14th days, the observation group's amount of ET-1 was lower than that of the general group (P<0.05); The observation group's FMD of patients on the 14th day was inferior to the general group after treatment (P<0.05); The observation group's overall effective rate was 94.44% higher than the general group's (P<0.05); The observation group experienced fewer negative responses than the general group did (P<0.05). In conclusion, ST-ⅡAS can be used for uric acid, vascular endothelial systolic and diastolic function in patients with HC-CHD, and has better clinical efficacy and lower risk of adverse reactions.

Influence of Goniotomy Size on Treatment Safety and Efficacy for Primary Open-Angle Glaucoma: A Multicenter Study.

PURPOSE: To compare the efficacy and safety of 120-, 240-, and 360-degree goniotomy (GT) with or without phacoemulsification with intraocular lens implantation (PEI) for patients with primary open-angle glaucoma (POAG). DESIGN: Multicenter, retrospective, comparative, nonrandomized interventional study. METHODS: Patients diagnosed with POAG who underwent GT with or without PEI were included, and divided into 6 groups: 1) standalone 120-degree GT (120GT); 2) standalone 240-degree GT (240GT); 3) standalone 360-degree GT (360GT); 4) PEI + 120GT; 5) PEI + 240GT; and 6) PEI + 360GT. Data on intraocular pressure (IOP), the number of ocular hypotensive medications, and complications were collected and compared. Success was defined as a postoperative IOP within the range of 6 to 18 mm Hg and a 20% reduction from baseline without further glaucoma surgery. Complete success and qualified success were defined as the above without and with ocular hypotensive medications, respectively. RESULTS: Three hundred eight eyes of 231 patients were included with a mean follow-up of 14.4 ± 8.6 months (6.0-48.0 months). There were no significant differences in the reductions in IOP and number of medications and cumulative survival probability for complete and qualified success rates among the 3 groups of standalone GT and PEI + GT. The 360GT group had the highest proportion of hyphema with or without PEI. CONCLUSIONS: 120GT, 240GT, and 360GT with or without PEI showed similar efficacy in reducing IOP and medications used in POAG. 360GT with or without PEI was more likely to cause hyphema compared with 120GT or 240GT. 120GT with or without PEI was sufficient for treating POAG with or without cataract..

Polystyrene nanospheres-induced hepatotoxicity in swamp eel (Monopterus albus): From biochemical, pathological and transcriptomic perspectives.

As ubiquitous emerging pollutants, microplastics (MPs) in aquatic environments have aroused critical global concerns. Despite the occurrence and characteristics of MPs in freshwater agroecosystems well-described by our previous study, their ecotoxicological implications in Monopterus albus remains unfathomed. Herein, we dissected toxic effects and mechanisms of PS-NPs exposure against M. albus hepatic tissues at concentrations of 0.5 (L), 5 (M), 10 (H) mg/L for 28 days using physiochemical measurements, histopathological analysis and transcriptomic sequencing. Results showed that upon PS-NPs treatments, levels of ROS, MDA, 8-OHdG and MFO activity were significantly enhanced relative to the control (C) group, while SP content and T-AOC activity were dramatically suppressed, suggesting ROS burst, lipid peroxidation and DNA damage may occur in liver tissues. This oxidative damage further triggered impaired hepatic function and histopathology, disordered lipid metabolism and hepatocyte apoptosis, as reflected by significantly diminished activities of GPT, GOT, ACP, AKP and LDH, paralleled with augmented levels of TG, TC and HSI as well as Cytc and Caspase-3,8,9 activities. Noticeably, concentration-dependent rises of apoptotic rate, vacuolar degeneration and lipid deposition were manifest in TUNEL, H&E and ORO staining. In addition, a total of 375/475/981 up-regulated as well as 260/611/1422 down-regulated DEGs in C vs L, C vs M and C vs H categories were identified based on RNA-seq, respectively. These DEGs were significantly annotated and enriched into GO terms (membrane, cytoplasm, response to stimuli, oxidation-reduction process) as well as KEGG pathways (ether lipid metabolism, apoptosis, chemical carcinogenesis-reactive oxygen species, non-alcoholic fatty liver disease). Moreover, signaling cascades Keap1-Nrf2, p53 and PPAR were either substantially initiated or dysregulated to orchestrate PS-NPs hepatotoxicity featuring oxidative damage, hepatocyte apoptosis and lipid steatosis. Collectively, this study not only expounded on toxicological mechanisms whereby PS-MPs exerted deleterious effects on M. albus, but also pointed to ecological risks of PS-MPs-induced hepatoxicity and lipid steatosis in this commercially-important species.

Effect of fenofibrate on blood lipid, sICAM-1, ET-1 and prognosis in chronic heart failure patients complicated with diabetes.

This study was to observe the effects of fenofibrate on blood lipid, sICAM-1, ET-1 and prognosis in chronic heart failure patients complicated with diabetes. For this purpose, a total of 126 chronic heart failure patients complicated with diabetes admitted to our hospital from September 2020 to October 2021 were selected and divided into a control group and an observation group by random number table method, with 63 cases in each group. The control group received conventional drug treatment, and the observation group received fenofibrate treatment on the basis of the control group. After 12 months follow-up, the levels of blood lipid, sICAM-1, ET-1 were compared between the two groups at 3 months before and after treatment and 6, 12 months after treatment. Results showed that after 3 months of treatment, LDL-C, TG and TC were lower in the observation group than in the control group, showing a statistically significant difference (P<0.05). After 3 months of treatment, HDL-C was higher in the observation group than in the control group, showing a difference (P<0.05). After 3 months of treatment, sICAM-1 and ET-1 were lower in the observation group than in the control group, showing a difference (P<0.05). There was no significant difference in mortality after 6 months of treatment, re-hospitalization rate and mortality after 12 months of treatment between the two groups (P>0.05). The re-hospitalization rate of the observation group was 4.76% (3/63) after 6 months of treatment, which was lower than that of the control group in the same period, showing a significant difference (P<0.05). The conclusion was that fenofibrate can regulate blood lipids in chronic heart failure patients complicated with diabetes, inhibit sICAM-1 and ET-1, and reduce the re-hospitalization rate within 6 months after treatment. However, the effects on long-term re-hospitalization rate and mortality risk are consistent with those of conventional treatment.

Dietary polystyrene nanoplastics exposure alters hepatic glycolipid metabolism, triggering inflammatory responses and apoptosis in Monopterus albus.

Microplastics and nanoplastics (MPs and NPs) are abundant, persistent, and widespread environmental pollutants that are of increasing concern as they pose a serious threat to ecosystems and aquatic species. Identifying the ecological effects of NPs pollution requires understanding the effects of changing nanoplastics concentrations in aquatic organisms. Monopterus albus were orally fed three different concentrations of 100 nm polystyrene nanoplastics (PS-NPs): 0.05 %, 0.5 %, and 1 % of the feed for 28 days. Nanoplastics significantly activated the PPAR signaling pathway, Acyl-CoA oxidase 1 (ACOX1), carnitine palmitoyltransferase 1a (CPT1A), angiopoietin-like 4 (ANGPTL4), and phosphoenolpyruvate carboxykinase (PCK) at the mRNA level, resulting in disturbed lipid metabolism. Glutathione peroxidase (GSH-px) activity, catalase (CAT) activity, and malondialdehyde (MDA) were significantly elevated in the high nanoplastics-feeding exposure group, leading to oxidative stress in the liver. Overexpression of the cytokines genes Interleukin 1 (IL1B) and Interleukin-8 (IL8), Tumor necrosis factor alpha (TNF-α), activation of MAPK signaling pathway, and increased gene expression of c-Jun amino-terminal kinases (JNK) and p38 indicate that exposure to NPs may lead to hepatopancreas apoptosis through oxidative stress and inflammation. In summary, dietary PS-NPs exposure alters hepatic glycolipid metabolism, triggering inflammatory responses and apoptosis in M. albus. The results of this study provide valuable ecotoxicological data for a better understanding of the biological fate and effects of nanoplastics in M. albus.

Outcomes of Partial Versus Complete Goniotomy With or Without Phacoemulsification for Primary Open Angle Glaucoma: A Multicenter Study.

PRCIS: Goniotomy (GT) 120 degrees with or without phacoemulsification was sufficient to lower the intraocular pressure (IOP) and reduce hyphema for primary open angle glaucoma. PURPOSE: To compare the surgical outcomes and safety profiles of 120 degrees and 360 degrees GT with or without phacoemulsification cataract extraction and intraocular lens implantation (PEI) for primary open angle glaucoma. PATIENTS AND METHODS: This multicenter retrospective study consisted of 139 eyes and was divided into 4 groups: (1) 120 degrees GT, (2) 360 degrees GT, (3) PEI + 120 degrees GT, and (4) PEI + 360 degrees GT. IOP, number of topical hypotensive medications, and complications were recorded and evaluated at baseline and at the final visit. The complete and qualified success rate and their potential associated factors were also investigated. The effectiveness and safety profile of the surgery were compared between different subgroups. RESULTS: After a mean follow-up of 8.6 months, the IOP reduction was 13.2 ± 8.3 (38.8 ± 28.8%), 12.4 ± 8.3 (41.6 ± 18.2%), 12.8 ± 9.9 (39.4 ± 34.5%), and 13.8 ± 7.2 (46.0±17.1%) mm Hg in 120 degrees, 360 degrees, PEI + 120 degrees GT group, and PEI + 360 degrees GT, respectively. No significant difference was found in IOP, a decline of IOP from baseline, topical hypotensive medication, and complete or qualified success between either standalone 120 degrees versus 360 degrees GT, or PEI + 120 degrees versus PEI + 360 degrees GT (all P s > 0.05). The PEI + 120 degrees GT group had a lower final IOP than the 120 degrees GT group ( P = 0.0002) whereas there was no difference between PEI + 360 degrees GT and 360 degrees GT group ( P = 0.893). Both 360 degrees GT and PEI + 360 degrees GT group had a significantly higher incidence of hyphema than the 120 degrees GT and PEI + 120 degrees GT groups (all P s < 0.0001). CONCLUSIONS: GT of 120 or 360 degrees lowered IOP equally with or without cataract surgery, and hyphema was most commonly noted after complete GT. Partial GT alone or in combination with cataract surgery was an effective and safe approach to manage patients with open angle glaucoma.

Chromosome-Level Assembly of Male Opsariichthys bidens Genome Provides Insights into the Regulation of the GnRH Signaling Pathway and Genome Evolution.

The hook snout carp Opsariichthys bidens is an important farmed fish in East Asia that shows sexual dimorphism in growth, with males growing faster and larger than females. To understand these complex traits and improve molecular breeding, chromosome-level genome assembly of male O. bidens was performed using Illumina, Nanopore, and Hi-C sequencing. The 992.9 Mb genome sequences with a contig N50 of 5.2 Mb were anchored to 38 chromosomes corresponding to male karyotypes. Of 30,922 functionally annotated genes, 97.5% of BUSCO genes were completely detected. Genome evolution analysis showed that the expanded and contracted gene families in the male O. bidens genome were enriched in 76 KEGG pathways, and 78 expanded genes were involved in the GnRH signaling pathway that regulates the synthesis and secretion of luteinizing hormone and glycoprotein hormones, further acting on male growth by inducing growth hormone. Compared to the released female O. bidens genome, the number of annotated genes in males was much higher (23,992). The male chromosome LG06 exhibited over 97% identity with the female GH14/GH38. Male-specific genes were identified for LG06, where structural variation, including deletions and insertions, occurred at a lower rate, suggesting a centric fusion of acrocentric chromosomes GH14 and GH38. The genome-synteny analysis uncovered significant inter-chromosome conservation between male O. bidens and grass carp, the former originating from ancestral chromosome breakage to increase the chromosome number. Our results provide a valuable genetic resource for studying the regulation of sexual dimorphism, sex-determining mechanisms, and molecular-guided breeding of O. bidens.

Quick detection of Carassius auratus herpesvirus (CaHV) by recombinase-aid amplification lateral flow dipstick (RAA-LFD) method.

Crucian carp (Carassius auratus) is one of the major freshwater species and is also a common food fish in China. Recently, Carassius auratus herpesvirus (CaHV) could induce fatal viral disease with high mortality of crucian carp, which had caused huge economic losses. In this study, we described a rapid and simple recombinase-aid amplification (RAA) assay coupled with lateral flow dipstick (LFD), which could achieve sensitive diagnosis of tumor necrosis factor receptor (TNFR) of CaHV within 35 min at 40°C. Our RAA-LFD method had a satisfactory detection limit of 100 gene copies per reaction, which was 100-fold more sensitive than traditional PCR. In addition, no cross-reaction was observed with other viral pathogens, including koi herpesvirus (KHV), cyprinid herpesvirus 2 (CyHV-2), infectious hematopoietic necrosis virus (IHNV), spring viremia of carp virus (SVCV) and grass carp reovirus (GCRV). Furthermore, the overall cost of the method was cut in half compared to previous studies. In conclusion, RAA-LFD assay is therefore, a promising alternative for point-of-care testing (POCT) of CaHV, which is feasible and of certain value in application of aquatic disease control.

Comparative transcriptome analysis of brain and gonad reveals reproduction-related miRNAs in the giant prawn, Macrobrachium rosenbergii.

Macrobrachium rosenbergii (M. rosenbergii), as a species of common prawn, is a delicacy that is consumed all over the world. By interacting with the target gene 3'-untranslated region (3'-UTR), microRNAs (miRNAs) regulate its expression and ultimately participate in the regulation of reproductive development. However, research focusing on miRNA regulation during gonadal development in M. rosenbergii received very little attention. To explore the association between miRNA and reproduction, we performed RNA sequencing (RNA-seq) on brain and gonad organs in male and female M. rosenbergii. A total of 494 miRNAs were obtained in RNA-seq, including 31 and 59 differentially expressed (DE) miRNAs in the brain and gonads, respectively. Furthermore, 9 DE miRNAs were randomly selected from the brain and gonads, and qRT-PCR was conducted to validate the results of RNA-seq. Interestingly, dpu-miR-133 was found to be substantially expressed in the male brain and testis but poorly expressed in the female brain, ovary, and other organs. Analysis of dpu-miR-133 by Targetscan and MiRanda predicted to target 5-HT1. Furthermore, the dual-luciferase reporter assay manifested that dpu-miR-133 can combine with 5-HT1. Overall, our research work provides basic data for further study on the miRNA-mediated regulation of brain, gonad, and reproductive development of study M. rosenbergii.

Identification and expression analysis of sex biased miRNAs in chinese hook snout carp Opsariichthys bidens.

As an economically important fish, Opsariichthys bidens has obvious sexual dimorphism and strong reproductive capacity, but no epigenetics study can well explain its phenotypic variations. In recent years, many microRNAs involved in the regulation of reproductive development have been explored. In this study, the small RNA libraries of O. bidens on the testis and ovary were constructed and sequenced. A total of 295 known miRNAs were obtained and 100 novel miRNAs were predicted. By comparing testis and ovary libraries, 115 differentially expressed (DE) miRNAs were selected, of which 53 were up-regulated and 62 were down-regulated. A total of 64 GO items (padj < 0.01) and 206 KEGG pathways (padj < 0.01) were enriched in the target gene of miRNA. After that, the expression levels of nine DE miRNAs, including let-7a, miR-146b, miR-18c, miR-202-5p, miR-135c, miR-9-5p, miR-34c-3p, miR-460-5p and miR-338 were verified by qRT-PCR. Furthermore, bidirectional prediction of DE miRNAs and sex-related genes was carried out and the targeting correlation between miR-9-5p and nanos1 was verified by Dual-Luciferase reporter assay. Our findings identified the differentially expressed miRNA and paved the way to new possibilities for the follow-up study on the mechanism of miRNA-mRNA interaction in the gonads of O. bidens.

Investigation of membrane fouling and mechanism induced by extracellular organic matter during long-term exposure to pharmaceuticals and personal care products.

This study investigated ultrafiltration membrane fouling by extracellular organic matter (EOM) and the mechanism operating during long-term exposure to pharmaceuticals and personal care products. The results indicated that carbamazepine and diclofenac in algal-laden water altered the filtration flux and membrane fouling by EOM. Exposure to low-concentration carbamazepine (0.25 µg/L) improved the filtration flux and the total (Rtot) and reversible fouling resistance (Rc), whereas the filtration flux and Rtot and Rc were reduced when EOM was used during long-term exposure to high carbamazepine concentrations (>1 µg/L). Both Rtot and Rc were increased when algae were exposed to 0.25 µg/L diclofenac, whereas the filtration flux and Rtot and Rc were alleviated when algae were exposed to >1 µg/L diclofenac. Moreover, carbamazepine and diclofenac (0.25 µg/L - 1000 µg/L) in water enhanced the irreversible fouling resistance (Rb) when ultrafiltration was used to treat algal-laden waters. The mechanism indicated that membrane fouling induced by standard blocking was transformed to complete blocking when EOM was exposed to high levels of carbamazepine (>0.25 µg/L) in the initial filtration process, whereas cake layer formation played an important role during the later filtration process; with low carbamazepine levels (0.25 µg/L), standard blocking of EOM was dominant during the entire filtration process. The membrane fouling mechanism also changed when algal-laden waters were exposed to diclofenac, the membrane fouling was transformed from complete blocking to standard blocking when DFC was present in the initial filtration process, whereas cake layer formation exerted an important role during the late filtration process. This research provides important information on the long-term risks caused by pharmaceutical and personal care products and potential threats to membrane treatment.

Differential Expression of Duplicate Insulin-like Growth Factor-1 Receptors (igf1rs) in Medaka Gonads.

Insulin-like growth factor-1 receptors (igf1rs) play important roles in regulating development, differentiation, and proliferation in diverse organisms. In the present study, subtypes of medaka igf1r, igf1ra, and igf1rb were isolated and characterized. RT-PCR results showed that igf1ra and igf1rb mRNA were expressed in all tissues and throughout embryogenesis. Using real-time PCR, the differential expression of igf1ra and igf1rb mRNA during folliculogenesis was observed. The results of in situ hybridization (ISH) revealed that both of them were expressed in ovarian follicles at different stages, and igf1rb was also expressed in theca cells and granulosa cells. In the testis, both igf1ra and igf1rb mRNA were highly expressed in sperm, while igf1rb mRNA was also obviously detected in spermatogonia. In addition, igf1ra mRNA was also present in Leydig cells in contrast to the distribution of igf1rb mRNA in Sertoli cells. Collectively, we demonstrated that differential igf1rs RNA expression identifies medaka meiotic germ cells and somatic cells of both sexes. These findings highlight the importance of the igf system in the development of fish gonads.

Asian Swamp eel Monopterus albus Population Structure and Genetic Diversity in China.

The Asian swamp eel (Monopterus albus) is one of the most widely distributed freshwater fish in China. In this study, we identified the single nucleotide polymorphisms (SNPs) of M. albus from 19 wild populations in China using restriction-site associated DNA sequencing (RAD-seq), and used SNP markers to investigate the swamp eel the genetic diversity and population genetic structure. A total of 8941794 SNPs were identified. Phylogenetic and principal component analysis suggested that the 19 populations were clustered into four groups: The Jiaoling County (JL) and Poyang Lake (PYH)populations in Group Ⅰ; the Chengdu City (CD), Dali City (YN), Eli Village (EL), Dongting Lake (DTH), Huoqiu County (HQ), and Chaohu Lake (CH) populations in Group Ⅱ; the Puyang City (PY), Chongming Island (CM), Tai Lake (TH), Gaoyou Lake (GYH), Weishan Lake (WSH), Haimen City (HM), Hongze Lake (HZH), Baiyangdian Lake (BYD), Dagushan (DGS), and Pinghu City (PH) populations in group Ⅲ; and the Lingshui County (LS) populations in Group Ⅳ. All 19 populations may have evolved from four ancestors. The genetic diversity was relatively high in CM, GYH, and HM; and low in LS, EL, and JL. The LS, and CM populations had the highest and lowest differentiation from the other populations, respectively. These findings provide new insights for germplasm resources protection and artificial breeding of M. albus.