Bulukumba Regency, South Sulawesi, Indonesia is one of the centres for whiteleg shrimp, Litopenaeus vannamei production that applies intensive technology. However, no information has been obtained regarding the characteristics and status of water quality in coastal areas with environmentally friendly concepts and the potential to receive a waste load. The study aimed to determine the performance of whiteleg shrimp culture in relation to temporal and spatial aspects and characteristic and water quality status. Measurement and sampling of water were carried out before stocking/initial of culture whiteleg shrimp (rainy season) and end of culture/after harvesting of whiteleg shrimp (dry season) at two locations in the coastal area of ​​Bulukumba Regency, namely Bonto Bahari Subdistrict (BB) and Gantarang Subdistrict (GT). Variables measured and analyzed included temperature, salinity, pH, dissolved oxygen, nitrate, nitrite, ammonia, phosphate, total suspended solids, and total organic matter. Data analysis with descriptive statistics, multivariate statistics, and non-parametric statistics. The Storet (Storage and Retrieval) method was used to determine the water quality status. The results showed that the culture of whiteleg shrimp was technology-intensive with a stocking density of 110 - 220 ind/m² with productivity between 13.9 - 44.4 tons/ha/cycle. The predicted waste load of N is 28.00 tons/cycle and P reaches 6.61 tons/cycle. Another result was that changes in water quality status during the rainy season were classified as moderately polluted at the BB location and complying quality standards at the GT location, while in the dry season, both locations were categorized as heavily polluted. Variables of water quality that caused the decrease in water quality status in both locations (BB and GT) were observed to increase salinity, nitrate concentration, and ammonia concentration. However, there was a decrease in dissolved oxygen concentration in the dry season.

Suppressors of cytokine signaling (SOCS) genes are essential negative regulators that modulate cytokine signaling and play key roles in numerous biological processes, including immune responses. In this study, we cloned the complementary DNA (cDNA) sequences of two SOCS genes, designated as LvSOCS6 and LvSOCS7, from the white-leg shrimp, Litopenaeus vannamei. LvSOCS6 encoded a polypeptide of 463 amino acids (aa), spanning 1,392 base pairs (bp), while LvSOCS7 encodes a significantly larger polypeptide of 955 aa, encompassing 2,868 bp. Both LvSOCS proteins exhibited conserved domains associated with SOCS, including a centralized Src homology 2 (SH2) domain and a C-terminal SOCS box. Phylogenetic analysis revealed that the deduced aa sequences of LvSOCS6 and LvSOCS7 cluster within the invertebrate type I SOCS family, indicating their evolutionary relatedness. Tissue distribution analysis demonstrated ubiquitous expression of both LvSOCS genes across all examined tissues, with LvSOCS6 showing heightened expression in the gills and LvSOCS7 exhibiting a remarkable preference for the gills and stomach. Notably, mRNA expression patterns of LvSOCS genes following LPS and poly (I:C) stimulations exhibit significant upregulations, while PGN stimulation yields incongruous results across the experimented tissues. Interestingly, concurrent with the diminished expression of LvSOCS6 and LvSOCS7, there is a significant elevation in mRNA expression levels of LvSTAT, a vital component of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway. These findings shed light on the potential involvement of the newly discovered type I SOCS genes in regulating the JAK/STAT pathway and assuming pivotal roles in orchestrating the innate immune responses in L. vannamei defense mechanisms.

MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1) serves as a pivotal mediator for NF-κB activation in response to a wide spectrum of transmembrane receptor stimuli. In the present study, a homolog of MALT1 is cloned from the Pacific white shrimp (Litopenaeus vannamei) named LvMALT1, and its potential function in shrimp innate immunity are explored. The open reading frame of LvMALT1 is 2364 bp that encodes 787 amino acids. The predicted LvMALT1 protein structure comprises a death domain, three immunoglobulin domains, and a caspase-like domain, exhibiting remarkable similarity to other homologs. LvMALT1 is a cytoplasmic-localized protein and could interact with LvTRAF6. Overexpression of LvMALT1 induces the activation of promoter elements governing the expression of several key antimicrobial peptides (AMPs), including Penaeidins (PENs) and Crustins (CRUs). Conversely, silencing of LvMALT1 leads to a reduction in the phosphorylation levels of Dorsal and Relish, along with a concomitant decline in the in vivo expression levels of multiple AMPs. Furthermore, LvMALT1 is prominently upregulated in response to a challenge by the white spot syndrome virus (WSSV), facilitating the NF-κB-mediated expression of AMPs as a defense against viral infection. Taken together, we identified a MALT1 homolog from shrimp L. vannamei, which plays a positive role in the TRAF6/NF-κB/AMPs axis mediated innate immunity.

The global shrimp farming industry is impacted by various infectious diseases, leading to marked production losses. Virulent Vibrio parahaemolyticus strains (VPAHPND) and other Vibrio species cause acute hepatopancreatic necrosis disease (AHPND) in shrimp. We isolated a binary toxin PirA/B-bearing V. campbellii strain (HJ-2023) from a Korean shrimp farm. The biochemical characteristics and antibiotic susceptibility of HJ-2023 were analyzed and compared to those of PirA/B-bearing VPAHPND. Non-AHPND-causing V. campbellii was the control. The pathogenicity of each strain was analyzed in white-leg shrimp. Phylogenetic analysis classified the isolated HJ-2023 strain as V. campbellii. Biochemical tests confirmed distinct properties of HJ-2023, compared to the genetically similar V. harveyi group. The AHPND-causing toxin gene of HJ-2023 showed 100% similarity to the rpoD gene of VCAHPND. An antibiotic disc susceptibility test indicated that HJ-2023 showed resistance to ampicillin, clindamycin, lincomycin, and erythromycin, which is effective against gram-positive bacteria, and showed weak sensitivity to gentamycin. Furthermore, HJ-2023 was 25% less toxic than VPAHPND but could be lethal during aquaculture-related outbreaks. These results highlight the complexity and virulence of AHPND-causing strains through multiple pathways and confirm the pathogenicity of V. campbellii, which increases the risk posed by AHPND to shrimp aquaculture. Our findings could help prevent AHPND.

pH is the major factor that makes producers in aquaponics frustrated, since the main three organisms (aquatic animal, plant, and microbes) in the system with different preferences. Yet, amending the growing environment with additional C is a potential method to improve the growth of shrimp and plants as well as the establishment of microbe. A detailed study of the effects of pH and additional C on aquaponics under saline conditions has not been investigated. In this study, the effect of pH and additional C on the growth performance of shrimp (Litopenaeus vannamei) and five edible plants in marine aquaponic systems using the nutrient film technique (NFT) was evaluated. The results indicated that at both pH 6.5 treatments, plants grew better; nevertheless, the growth performance of plants in pH 7.5 with additional C was improved and showed a similar yield to lower pH treatments. On the other hand, shrimp growth was little affected by pH and additional C. A higher impact of imbalanced ionic composition on shrimp performance may have contributed to this trend. Hence, we suggest that only if the ionic composition is managed can make RO water a suitable source of water for shrimp-based aquaponic. In spite of this, more research is required.