Microencapsulation is an advanced technique used to improve the viability of probiotics and minimize sensitivity during processing, storage, and in the gastrointestinal environment. Two dietary treatments including a control and an encapsulated probiotic, Bacillus subtilis E20 (EP), were used to evaluate the efficacy in improving the intestinal microbiome of white shrimp, Penaeus vannamei, after a 60-feeding trial. The 16S rDNA next-generation sequencing (NGS) analysis indicated that shrimp fed the EP diet generated higher amplicon reads than shrimp fed the control diet. No significant differences were observed in the α-diversity index of the intestinal microbiota of shrimp that were fed the control and EP diet. At the phylum level, Proteobacteria was relatively abundant in the microbiota of shrimp fed both the control and EP diet. The treatment with EP increased the expression of Tenericutes, Bacteroidetes, and Firmicutes, more than the control. The PC analysis revealed that the EP diet altered the bacterial profile in shrimp’s intestines into forming different clusters. Unique genera such as Luteolibacter, Simkaniaceae, Haemophilus, Pirellulaceae, Filomicrobium, Sphingomonas, and Erysipelotrichaceae UCG-003 along with well-known probiotic genera Bacillus and Lactobacillus were found in the intestine of shrimp fed the EP diet. The PCA eigenvector plots indicated a higher abundance of Bacillus in shrimp fed with EP diet, but a higher abundance of Vibrio in shrimp fed with control diet. These results suggest that encapsulated B. subtilis E20 can be beneficial to shrimp microbiota.

An experiment was conducted to evaluate the effects of the Micro-Aid Liquid 10 (MAL10) (DPI Global, Porterville, CA, USA), a product made from yucca extract, on growth performance, gut microbiota, and resistance of white shrimp, Litopenaeus vannamei against infectious disease caused by Vibrio alginolyticus. MAL10 was added to shrimp rearing water at different levels of 0 (control), 0.25 mL m³⁻¹ (W0.25), 0.5 mL m³⁻¹ (W0.5), 1 mL m³⁻¹ (W1), and 5 mL m³⁻¹ (W5), respectively, once per week for 70 days. Growth performances, including final body weight, specific growth rate, average daily growth and percentage of weight gain, were significantly improved by adding the MAL10 at levels up to 5 mL m³⁻¹, which may be due to the proliferation of B cells in hepatopancreas of MAL10-treated shrimp. No significant differences in the total viable count and Vibrio-like count in the gut of shrimp were recorded by spread plate method. In the challenge test, shrimp reared in the water supplemented with MAL10 at levels of 1–5 mL m³⁻¹ had significantly lower cumulative mortality after a challenge test with V. alginolyticus compared to shrimp reared in the control, W0.25 and W0.5 groups. Next-generation sequencing indicated that the relative distribution of phylum Proteobacteria in control (80.4%) was higher than the W (77.4%). The proportion of Vibrio was primarily dominant genera in the shrimp intestine and highest in the control group compared to the W group, followed by Spongiimonas, Motilimonas, Demequina, and Shewanella genera. Although there was no statistically significant difference, higher α-diversity indices were recorded in the W5-treated group than in the control group. Therefore, it is considered that MAL10 could be used as a natural alternative in shrimp aquaculture to reduce the risk of infectious disease caused by pathogenic Vibrio and improve the growth performance of white shrimp.

Mastitis is a major issue in dairy cows, with subclinical mastitis (SCM) being hard to detect and potentially progressing to clinical mastitis. Antibiotic use raises concerns about resistance and milk contamination, highlighting the need for natural alternatives. Sodium alginate (SA), known for its antioxidant and immunomodulatory properties, may offer a solution, though its effects on mastitis are unclear. Intramammary infusion of 1% SA (30 mL) was tested in both healthy cows (n = 8; somatic cell count, SCC ≤ 100,000 cells/mL) and those with SCM (n = 12; SCC ≥ 200,000 cells/mL). The results showed that SA significantly increased SCC in both healthy and SCM cows, with peak levels at 48 h, returning to baseline levels thereafter. In cows with SCM, SA treatment led to a 58.3% cytological and 54.5% bacteriological cure rate after 14 days. Additionally, significant downregulation was observed in tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-2, IL-4, IL-6, and interferon (IFN)-γ. Conversely, the levels of IL-8, IL-10, and IL-12 initially increased, then declined gradually. Importantly, there were no significant effects on milk composition. These findings suggest that SA may offer an alternative to antibiotics, aiding in immune response and bacterial clearance without the risk of antibiotic residues, thus preventing SCM progression to clinical mastitis.