Zhao Chen

Greenhouse aquaculture is an increasingly advanced practice in shrimp farming. This study employs Life Cycle Costing (LCC) and Life Cycle Assessment (LCA) to systematically evaluate the economic and environmental performance of greenhouse shrimp farming. Research data were collected from field surveys and enterprise production records to analyze the construction and farming processes of the aquaculture facilities. LCC analysis revealed that the life cycle cost was 3.56 USD kg⁻¹ shrimp. The construction cost of the greenhouse was 4.58 USD m⁻², with steel pipes and film materials being the dominant cost components. The total farming cost per cultivation cycle reached USD 3510.76 per greenhouse, of which feed (30.54%) and land rent (15.86%) were the primary expenses. This model achieved a net profit of USD 5.31 per m² per cycle and a cost-profit ratio of 60.47%, values which are significantly higher than those reported for the Indoor Super-Intensive Culture (ISIC) model. LCA results demonstrated that the environmental impact per kilogram of shrimp produced via greenhouse aquaculture was characterized by a global warming potential (GWP) of 3.279 kg CO₂ eq, an acidification potential (AP) of 0.369 kg SO₂ eq, and a eutrophication potential (EP) of 0.212 kg PO₄ equation Furthermore, the abiotic depletion potential (ADP) and human toxicity potential (HTP) were relatively low, at 0.002 kg Sb eq and 0.093 kg 1,4-DCB eq per kilogram of shrimp, respectively. The construction phase had the highest greenhouse gas emissions (GWP 1940.00 kg CO₂ eq), mainly due to the consumption of steel (steel pipes accounting for 71.6% of CO₂ emissions) and polymer materials. During the farming phase, the primary emissions per kilogram of shrimp produced were GWP (3.23 kg CO₂ eq), AP (0.27 kg SO₂ eq), and EP (0.212 kg PO₄ eq). The findings indicate that this greenhouse model possesses considerable advantages in balancing economic output and risk management, rendering it suitable for promotion in appropriate regions. Further reductions in cost and environmental impact can be achieved by optimizing building material selection, implementing precision feeding strategies, and improving the energy utilization structure. These measures will enhance the economic and environmental benefits of greenhouse shrimp farming and promote the green development of the entire aquaculture industry.

To investigate the structure and successional dynamics of microbial communities in shrimp culture ponds in coastal saline–alkali regions of Hebei, China, we compared the water microbiota of Litopenaeus vannamei monoculture ponds and L. vannamei–Macrobrachium rosenbergii polyculture ponds in the early, mid, and late culture stages. The results revealed clear temporal succession patterns in both the diversity and composition of microeukaryotic and bacterial communities. Distinct differences were also observed between the two culture models. Compared with monoculture, polyculture ponds showed 2.23–34.76% lower abundances of parasitic microeukaryotes, such as Rozellomycota and Perkinsida. In contrast, the abundances of carbon- and nitrogen-cycling bacterial groups (e.g., LD29, CL500-29_marine_group) and Chlorophyta were 0.24–50.94% higher in the polyculture system. Co-occurrence network analysis showed that polyculture enhanced competitive interactions and increased the network structural complexity within bacterial and cross-domain microbial networks. These findings help elucidate the mechanisms underlying efficient shrimp production in saline–alkali ponds and support the optimization of aquaculture models.

Tannic acid (TA) has great potential as a new feed additive. In this study, we investigated the effects of dietary TA on growth, digestion, nonspecific immunity, and resistance to ammonia stress and intestinal microbiota in Litopenaeus vannamei. The shrimp were fed diets containing different levels of TA: 0 mg/kg (TA-0), 200 mg/kg (TA-200), 400 mg/kg (TA-400), and 800 mg/kg (TA-800) for 56 days, followed by acute ammonia stress for 48 h. The results showed that dietary TA increased the survival rate of the TA-800 group. Dietary TA could improve the morphology of the hepatopancreas and intestinal tissues. After feeding different levels of TA for 56 days, the activities of amylase (AMS) and trypsin (Tryp) were increased, but the activity of lipase (LPS) was decreased. The activities of T-AOC, SOD, and PPO were higher in the hepatopancreas of the three TA treatment groups (p < 0.05). When shrimp were exposed to ammonia stress for 48 h, the activity of immune enzymes (LZM, T-AOC and SOD) and the expression levels of immune genes (LZM, proPO and Cu/Zn-SOD) were higher in the three TA treatment groups (p < 0.05). Furthermore, dietary TA also changed the composition of intestinal microflora by increasing the abundance of Planctomycetes, but decreasing the abundance of Bacteroides and Proteobacteria. The abundance of Rhodopirellula, Ruegeria, and Rhodobacter were higher, but that of Paracoccus, Algoriphagus, Cellvibrio, Flavobacteriaceae, and Bacteroides were lower in response to dietary TA. These results revealed that dietary TA had a positive effect on growth and intestinal microbial composition and enhanced the immune response to ammonia stress in shrimp. Therefore, TA can be a potential natural alternative antibiotic substitute for feed additives in shrimp, and the appropriate supplemental dosage is 400–800 mg/kg in the diet.