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Abstract Object detection plays a vital role in remote sensing applications. Although object detection has achieved proud results in natural images, these methods are difficult to be directly applied to remote sensing images. Remote sensing images often have complex backgrounds and small objects, which results in a highly unbalanced distribution of foreground and complex background information. In order to solve the above problems, this paper proposes a multi-head channel and spatial trans-attention (MCSTA) module, which performs remote pixel interaction from the channel and spatial dimensions respectively to complete the attention feature capture function. It is a plug-and-play module that can be easily embedded in any other natural image object detection convolutional neural network, making it quickly applicable to remote sensing images. First, in order to reduce computational complexity and improve feature richness, we use a special linear convolution to obtain three projection features instead of the simple matrix multiplication transformation in Transformer. Second, we obtain trans-attention maps in different dimensions in a manner similar to the self-attention mechanism to capture the interrelationships of features in channels and spaces. In this process, we use a multi-head mechanism to perform parallel operations to improve speed. Furthermore, in order to avoid large-scale matrix operations, we specially designed an attention blocking mode to reduce computer memory usage and increase operation speed. Finally, we embedded the trans-attention module into YOLOv8, added a new detection head and optimized the feature fusion method, thus designing a lightweight small object detection model named TA-YOLO for remote sensing images. It has fewer parameters than the benchmark model YOLOv8, and its mAP on the PASCAL VOC and VisDrone data sets increased by 1.3% and 6.2% respectively. The experimental results prove the powerful function of the trans-attention module and the excellent performance of TA-YOLO.

IntroductionDecapod iridescent virus 1 (DIV1) has caused severe economic losses in shrimp aquaculture. So far, Researchs on DIV1-infected shrimp have mainly focused on the hemocytes immune response, while studies on the host-intestine microbiota interactions during DIV1 infection have been scarce.MethodsThis study determined the lethal concentration 50 (LC50) of DIV1 to Metapenaeus ensis, preliminarily determining that M. ensis could serve as a susceptible object for DIV1. The interactions and responses between the immune and intestine microbiota of shrimp under DIV1 infection were also investigated.Results and DiscussionDIV1 infection decreases intestine bacterial diversity and alters the composition of intestine microbiota. Specifically, DIV1 infection decreases the abundance of potentially beneficial bacteria (Bacteroidetes, Firmicutes, and Actinobacteria), and significantly increases the abundance of pathogenic bacteria such as Vibrio and Photobacterium, thereby increasing the risk of secondary bacterial infections. The results of PICRUSt functional prediction showed that altered intestine microbiota induces host metabolism disorders, which could be attributed to the bioenergetic and biosynthetic requirements for DIV1 replication in shrimp. The comparative transcriptomic analysis showed that some metabolic pathways related to host immunity were significantly activated following DIV1 infection, including ncRNA processing and metabolic process, Ascorbate and aldarate metabolism, and Arachidonic acid metabolism. M. ensis may against DIV1 infection by enhancing the expression of some immune-related genes, such as Wnt16, heat shock protein 90 (Hsp90) and C-type lectin 3 (Ctl3). Notably, correlation analysis of intestinal microbial variation with host immunity showed that expansion of pathogenic bacteria (Vibrio and Photobacterium) in DIV1 infection could increased the expression of NF-κB inhibitors cactus-like and Toll interacting protein (Tollip), which may limit the TLR-mediated immune response and ultimately lead to further DIV1 infection.Significance and Impact of the StudyThis study enhances our understanding of the interactions between shrimp immunity and intestinal microbiota. The ultimate goal is to develop novel immune enhancers for shrimp and formulate a safe and effective DIV1 defense strategy.

In current dairy production, dietary energy is always excessively provided with a high-concentrate diet feeding to improve milk production. However, this feeding practice disturbed the rumen microbial ecosystem and the balance between ruminal energy and nitrogen, resulting in decreased nutrient fermentability, which in turn declined the milk yield of dairy cows. Therefore, supplementation of dietary degradable nitrogen may be helpful for high dairy production. In this study, we evaluated the regulatory effects of easily utilized enzymatic hydrolyzed cottonseed peptide (EHP) supplements on rumen microbiota communities and rumen nutrient fermentability under high-concentrate feeding. For this purpose, a gradient concentrate of EHP (from 0.2 to 1.0%) was added to the high-concentrate basal substrates for an in vitro experiment. Each treatment contained three replicates, with three bottles in each replicate. Rumen fermentable parameters included microbial protein content, volatile fatty acids, and ammonia-N; the rumen nutrient degradability of dry matter, crude protein, neutral detergent fiber, acid detergent fiber, ether extracts, calcium, and phosphorus were further investigated after in vitro fermentation for 72 h. Then, rumen microbiota communities and their correlation with ruminal fermentation parameters and rumen nutritional degradability were analyzed to understand the regulatory mechanism of the EHP supplements on rumen fermentability. Results indicate that treatment with 0.6% of EHP supplements had the highest content of acetate, butyrate, and neutral detergent fiber degradability among all treatments. Furthermore, EHP supplements significantly increased the relative abundance of rumen cellulose and starch-degrading bacteria such as Ruminococcus, Bifidobacterium, and Acetitomaculum, and the high nitrogen utilizing bacteria Butyrivibrio and Pseudobutyrivibrio, which may further promote the rumen carbohydrate and nitrogen metabolism. In summary, supplementation of easily degraded small peptides helps reestablish rumen energy and nitrogen balance to promote the rumen fermentable functions and nutritional degradability under high-concentrate diet feeding circumstances. These findings may further promote dairy production.

Subacute ruminal acidosis (SARA) becomes the most common nutritional metabolic disease in high-yielding dairy cows and later fatting beef cattle because of the increasing consumption of high-concentrate diets in modern feeding patterns. Our previous research found a certain piece of evidence that adding 180 mg thiamine/kg DMI could increase the rumen pH and regulate the structure of the rumen microbial community in vivo. However, there is still limited experimental data on the effects of SARA on thiamine status, the damage to the structure of rumen epithelial cells, and the underlying mechanism of the epithelium alterations. For this purpose, a total of 18 Angus bulls (average 22.0-months-old) with an average live weight of 567.6 ± 27.4 kg were randomly allocated into a control treatment (CON), a high-concentrate diet treatment (HC), and a high-concentrate diet with the vitamin B1 supplement treatment (HCB). All bulls were conducted with a 7-day adjustment period followed by a 60-day-long main feeding procedure. Results indicated that ADFI and ADG significantly decreased in the HC treatment compared with CON (P < 0.05), while significantly increased after the VB1 supplement (P < 0.05). Besides, ruminal acetate content was significantly downregulated while propionate was significantly upregulated under the HC treatment compared with CON (P < 0.05); however, these alterations showed a completely inverse regulatory effect on the VB1 supplement compared with HC (P < 0.05). These changes causatively induced a significant decrease in the A/P ratio in the HC treatment compared with CON and HCB treatments (P < 0.05). Bacterial communities in the HC treatment could be separated from those in CON through PCoA axes 1 and 2. Meanwhile, the VB1 supplement significantly altered the bacterial communities compared with the HC treatment, except for HCB-3. Furthermore, the HC treatment significantly upregulated the expression of JNK, Bax, Caspase-8, Caspase-3, Caspase-9, and Cyt-C compared with CON, while significantly downregulated the expression of Bcl-2. The VB1 supplement showed a complete converse gene expression compared with HC. In conclusion, the VB1 supplement could effectively attenuate the alterations that occurred when exposed to high-concentrate diets, and help promote production performance through increased fermentability.

In recent years, with global warming and increasing marine pollution, some novel marine viruses have become widespread in the aquaculture industry, causing huge losses to the aquaculture industry. Decapod iridescent virus 1 (DIV1) is one of the newly discovered marine viruses that has been reported to be detected in a variety of farmed crustacean and wild populations. Several previous studies have found that DIV1 can induce Warburg effect-related gene expression. In this study, the effects of DIV1 infection on intestinal health of shrimp were further explored from the aspects of histological, enzymatic activities, microorganisms and metabolites using Marsupenaeus japonicus as the object of study. The results showed that obvious injury in the intestinal mucosa was observed after DIV1 infection, the oxidative and antioxidant capacity of the shrimp intestine was unbalanced, the activity of lysozyme was decreased, and the activities of digestive enzymes were disordered, and secondary bacterial infection was caused. Furthermore, the increased abundance of harmful bacteria, such as Photobacterium and Vibrio, may synergized with DIV1 to promote the Warburg effect and induce metabolic reprogramming, thereby providing material and energy for DIV1 replication. This study is the first to report the changes of intestinal microbiota and metabolites of M. japonicus under DIV1 infection, demonstrating that DIV1 can induce secondary bacterial infection and metabolic reprogramming. Several bacteria and metabolites highly associated with DIV1 infection were screened, which may be leveraged for diagnosis of pathogenic infections or incorporated as exogenous metabolites to enhance immune response.

The study investigates the outcomes of adding sodium humate and sodium humate with probiotics (Lysinibacillus, Bacillus subtilis) to culture water on the growth performance, enzyme activity, and microbial environment of shrimp. The sodium humate and probiotics concentrations were 3 mg/L and 105 CFU/mL in the culture water. Litopenaeus vannamei (0.31 ± 0.03 g) at a density of 300 shrimps/m3 were cultured in nine buckets for a 43-days culture experiment. The results showed that the survival rate (SR) of L. vannamei in sodium humate group and sodium humate with probiotics group were (88.44%) and (86.07%), with the sodium humate group outcome being significantly better than the control group. The shrimps’ final body weight and specific growth rate (SGR) in the two experimental groups were significantly higher than the control group. The feed conversion rate (FCR) was significantly lower than the control group. The ammonia nitrogen concentration in sodium humate with probiotics group was significantly lower than the control group on the 15th day. The activities of intestinal amylase, lipase, trypsin and hepatopancreas superoxide dismutase (SOD), phenol oxidase (PO), and catalase (CAT) in sodium humate group were significantly higher than the control group. Notably, SOD, PO, and lipase activities in sodium humate with probiotics group were significantly higher than the control group. Illumina MiSeq high-throughput sequencing showed that the Chao and Ace indices of the culture water microflora in experimental groups were higher than the control group, and the sodium humate group was significantly higher than the control group. At the phylum level, Proteobacteria, Bacteroidetes, and Actinobacteria were the dominant bacterial communities in the intestine and culture water of L. vannamei, Proteobacteria was the most abundant phyla. At the genus level, the relative abundance of Pseudohongiella of water microflora in the control group was significantly lower than the experimental groups. Ruggiella (15.22-19.56%) was the most abundant genera of intestinal microflora. These results infer that the addition of sodium humate enhances the growth performance, digestive enzymes, and some immune enzyme activities, improving the richness of the water microbial community of L. vannamei.

“Fishery-photovoltaic (PV) Integration” is a novel aquaculture model that provides enormous potential for aquaculture development. However, research on the aquaculture environment and organisms under the “Fishery-PV Integration” mode is presently sparse. This study investigated Penaeus monodon as a model, studying the growth rates of shrimp, water quality conditions, and the micro-ecological environment. After 105 days of rearing, P. monodon (initial weight of 0.006 ± 0.001 g) reached an average body weight of 11.69 ± 0.92 g. The water quality was stable (C(NH4+) ≤ 1.57 mg/L) during the experimental period. The 16S rRNA gene sequencing results showed that bacterial community structures were significantly distinct among water, effluent and intestinal environments, with a closer relationship between the microbiotas in effluent and water. The dominant phyla present in shrimp intestines, water, and effluent were Proteobacteria, Actinobacteriota, and Bacteroidota. Likewise, Ralstonia, Candidatus Aquiluna, and Vibrio were the dominant genus in the three groups. The relative abundance of Vibrio as a common opportunistic pathogen for shrimp was relatively low, which is beneficial to promote the healthy growth of shrimp. The function of the “Fishery-PV Integration” microbiota was investigated using metagenomic technology. Results showed that microorganisms played an essential role in regulating intestinal amino acids, carbohydrate, and energy metabolisms. Antibiotic resistance genes (ARGs) data indicate that tetH, QnrVC6 and tetX were dominated ARGs in the intestine. At the same time, the ARGs with the highest relative abundance in the water and effluent groups were MexL and adeF. Notably, only 123 ARGs were identified within the “Fishery-PV Integration” pond. This outcome is significantly lower than other studies, indicating that shrimp cultured in the “Fishery-PV Integration” pond had a higher level of food safety. The current study describes the characteristics of the microflora and ARGs distribution in the “Fishery-PV Integration” pond for the first time, providing fundamental information for formulating management strategies for the whole microflora to maintain the health of shrimp.

Kelp powder, supplemented with a dairy cow diet, effectively improved the milk polyunsaturated fatty acids (PUFAs) content. However, little information exists on the downstream effects of the kelp-treated milk on body health, gut microbiota, and nutrient metabolism. For this purpose, 48 3-week old Kunming (KM) male mice with an average body weight of 16.1 g ± 0.2 g were randomly divided into the control treatment (CON, fed with standard chow), the common milk supplement treatment (Milk), and the kelp powder-treated milk supplement treatment (KPM). The experiment lasted for 35 days, with a 7-day long adaptive period and a 28-day long main trial. Phenotypic parameters including growth performances and serum lipids-related parameters were first measured, and results indicated that Milk and KPM supplement significantly promoted the total body weight gain (P < 0.05), while significantly decreasing the feed conversion ratio compared with CON (P < 0.05). No significant differences were observed in the blood lipids content among all three treatments, however, the triglyceride content showed a decreasing trend after KPM supplement treatment. Further, activities of liver lipometabolic-related enzymes were investigated to determine the underlying factors that impacted physiological lipid metabolism. KPM treatment showed a significant reductive effect on the activity of lipogenesis-related enzymes, such as FAS and ACC, while a significant stimulative effect on the activity of lipolysis-related enzymes included the ATGL and CPT1 compared with CON (P < 0.05). Finally, gastrointestinal tract development and cecal microbiota community that correlated with body lipid degradation and absorption were measured to determine the underlying mechanism of KPM supplementation on physiological lipid metabolism. Results indicated that supplementation with KPM significantly enhanced cecal bacteria diversity which was reflected in the significant increase of Chao1 and ACE indexes. Besides, starch-degraded bacteria such as Faecalibacterium, Ruminococcaceae, and Streptococcus are significant decreased (P < 0.05), while cellulose-degraded bacteria including Parabacteroides, Prevotella, Lactobacillus, Clostridium, and Bifidobacterium are significantly increased (P < 0.05) after KPM supplement, which may further restrict the energy generation and therefore reduce the lipid deposition. In summary, kelp supplement helped increase the milk PUFAs content, enhance the bacterial diversity and relative abundances of probiotics, which finally modulated physiological lipid metabolism, and promote growth performances.

Biofloc technology (BFT) is one of the most promising technologies in global aquaculture for the purpose of improving water quality, waste treatment, and disease prevention in intensive aquaculture systems. However, characterization of the microbial species and antibiotic resistance potentially present in biofloc-based aquaculture environments is needed. In this study, we used high-throughput sequencing technology to comprehensively compare the bacterial communities in mariculture ponds of Penaeus monodon (P. monodon), by testing of water, biofloc, and intestine of P. monodon. Operational taxonomic units (OTUs) cluster analysis showed that the nine samples tested divided into 45 phyla and 457 genera. Proteobacteria was the dominant bacteria in water, biofloc and prawn intestine. In biofloc and intestine, the Ruegeria (2.23–6.31%) genus represented the largest proportion of bacteria, with Marivita (14.01–20.94%) the largest group in water. Microbial functional annotation revealed that in all the samples, genes encoding metabolism were predominant. The antibiotic resistance gene annotation showed the highest absolute abundance of patB, adeF, OXA-243, and Brucella_suis_mprF from Proteobacteria. PatB (11.33–15.01%), adeF (15.79–18.16%), OXA-243 (35.65%), and Brucella_suis_mprF (10.03%) showed the highest absolute abundance of antibiotic resistance genes in water, biofloc, and intestines, respectively. These findings may greatly increase our understanding of the characteristics of the microbiota of shrimp biofloc-based aquaculture systems and the complex interactions among shrimp, ambient microflora, and environmental variables. It provides a reference basis for policy on breeding, environmental safety, and maintaining food safety in the production of P. monodon.

Unsynchronized growth is a common phenomenon in farmed crustaceans. The underlying molecular mechanism of unsynchronized growth of crustaceans is unclear. In this study, a comparative proteomic analysis focusing on growth differences was performed using kuruma shrimp Marsupenaeus japonicus, an economic crustacean species, as the model. The study analyzed kuruma shrimp at fast growth stage and steady growth stage from both fast growth group and slow growth group by an Isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomic analysis method. A total of 1,720 proteins, including 12,291 peptides, were identified. Fifty-two and 70 differentially expressed proteins (DEPs) were identified in the fast growth stage and steady growth stage, respectively. Interestingly, 10 DEPs, including 14-3-3-epsilon-like, GPI, GPD1, MHC-1a, and MHC-1b, were presented in both growth stages. In addition, all these 10 DEPs shared the same expression tendency at these two growth stages. The results indicated that these 10 DEPs are potential growth biomarkers of M. japonicus. Proteins associated with faster growth of M. japonicus may promote cell growth and inhibit cell apoptosis through the Hippo signaling pathway. The fast growth group of M. japonicus may also achieve growth superiority by activating multiple related metabolic pathways, including glycolysis, glycerophospholipid metabolism and Citrate cycle. The present study provides a new perspective to explore the molecular mechanism of unsynchronized growth in crustacean species.

As a new type of shrimp lethal virus, decapod iridescent virus 1 (DIV1) has caused huge economic losses to shrimp farmers in China. Up to now, DIV1 has been detected in a variety of shrimps, but there is no report in Marsupenaeus japonicus. In the current study, we calculated the LC50 to evaluate the toxicity of DIV1 to M. japonicus and determined through nested PCR that M. japonicus can be the host of DIV1. Through enzyme activity study, it was found that DIV1 can inhibit the activities of superoxide dismutase, catalase, lysozyme, and phenoloxidase, which could be a way for DIV1 to achieve immune evasion. In a comprehensive study on the transcriptomic changes of M. japonicus in response to DIV1 infection, a total of 52,287 unigenes were de novo assembled, and 20,342 SSR markers associated with these unigenes were obtained. Through a comparative transcriptomic analysis, 6,900 differentially expressed genes were identified, including 3,882 upregulated genes and 3,018 downregulated genes. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that some GO terms related to virus invasion, replication, and host antiviral infection were promoted under DIV1 infection, such as carbohydrate binding, chitin binding, chitin metabolic process, and DNA replication initiation, and some KEGG pathways related to immune response were significantly influenced by DIV1 infection, including Toll and IMD signaling pathway, JAK-STAT signaling pathway, IL-17 signaling pathway, C-type lectin receptor signaling pathway, complement and coagulation cascades, antigen processing and presentation, necroptosis, apoptosis, NOD-like receptor signaling pathway, apoptosis—multiple species, and TNF signaling pathway. Further analysis showed that STAT, Dorsal, Relish, heat shock protein 70 (HSP70), C-type lectins, and caspase play an important role in DIV1 infection. This is the first detailed study of DIV1 infection in M. japonicus, which initially reveals the molecular mechanism of DIV1 infection in M. japonicus by using the transcriptome analysis of hemocytes combined with enzyme activity study.

The article presents a study which showed that the calcium-dependent protein kinase 28 (CKP28) initiates a phosphorylation cascade to specify transcriptional reprogramming downstream of cold-induced calcium signal. Topics discussed include important role of calcium in plant responses to cold stress and Cold-Responsive (COR) gene expression, protein expression and purification from Escherichia coli, and quantification and statistical analysis.