This study aimed to investigate the potential probiotic Bacillus spp. from the intestine of Nile tilapia in order to construct a recombinant probiotic for the enhancement of the Nile tilapia immune response. One hundred bacterial isolates from the intestine of Nile tilapia were characterized for species identification using the 16s ribosomal RNA (rRNA). Only Bacillus isolates with exhibited antagonistic activity were investigated for their biological functions, which included protease-producing capacity, bile salts and pH tolerance, antibiotic susceptibility, and pathogenicity tests. According to the best results, Bacillus isolate B29, as closely related to B. subtilis, was selected to construct a recombinant probiotic for the delivery of CC chemokine protein (pBESOn-CC). The existence of recombinant probiotics was confirmed by Western blotting before the feeding trial. In addition, the CC chemokine mRNA level was quantified in the intestine of fish fed probiotics after 30 days of feeding. Total immunoglobulin, lysozyme activity, alternative complement 50 activity (ACH50), and phagocytic activity of fish fed either wild-type or recombinant probiotics were significantly increased, indicating that probiotics could stimulate the Nile tilapia immune system through different processes. Interestingly, the dietary supplementation of recombinant probiotics has a stronger immune response enhancement than the wild-type strain.

This study aimed to investigate the effects of DLs, including palm oil (PO; an SFAs), linseed oil (LO; n-3 PUFAs) and soybean oil (SBO; n-6 PUFAs) on the health status of Nile tilapia (Oreochromis niloticus) during adulthood. Three experimental diets incorporating PO, LO or SBO were fed to adult Nile tilapia for a period of 90 days, and haematological and innate immune parameters were evaluated. Proteome analysis was also conducted to evaluate the effects of DLs on plasma proteins. The tested DLs had no significant effects on red blood cell (RBC) count, haematocrit, haemoglobin, and total immunoglobulin and lysozyme activity. Dietary LO led to increased alternative complement 50 activity (ACH50), and proteome analysis revealed that PO and SBO enhanced A2ML, suggesting that different DLs promote immune system via different processes. Dietary LO or SBO increased the expression of several proteins involved in coagulation activity such as KNG1, HRG and FGG. Increased HPX in fish fed with PO suggests that SFAs are utilised in heme lipid-oxidation. Overall, DLs with distinct fatty acids (FAs) affect several parameters corresponding to health status in Nile tilapia, and dietary LO and SBO seemed to strengthen health in this species.

Two CXC chemokines in Nile tilapia (On-CXC1 and On-CXC2) were identified at both the genomic and proteomic levels. A southern blot analysis and comparison searching in Ensembl confirmed the typical structure of the CXC chemokine genes and provided evidence for unusual mechanisms used to generate the two different CXC chemokine transcripts that have not been reported in other vertebrate species so far. The expression levels of On-CXC1 and On-CXC2 were analyzed by quantitative real-time PCR. These two mRNAs were detected in various tissues of normal Nile tilapia, especially in the spleen, heart, and head kidney, indicating a homeostatic function in immunosurveillance. A time-course experiment clearly demonstrated that these two transcripts were effectively enhanced in the head kidney, spleen and trunk kidney of Nile tilapia 6, 12 and 24 h after injection with Streptococcus agalactiae but were down-regulated in all tested tissues at 48 h, reflecting the fact that they have short half-lives during the crucial response to pathogens that is characteristic of CXC chemokine genes in other vertebrates. Functional analyses obviously exhibited that these two CXC chemokines at concentrations of 1–10 μg strongly inactivated S. agalactiae and Flavobacterium columnare and effectively induced phagocytosis of leukocytes in vitro.

This study aimed to investigate how the consumption of purple neem foliage rich in anthocyanins improves rumen fermentation, growth performance and plasma antioxidant activity in growing goats. In total, 25 Anglo-Nubian Thai native male goats (about 20 ± 2 kg body weight; mean standard deviation (SD)) were assigned to 2 × 2 + 1 factorial in a completely randomized study design. There were five treatments: (1) control, (2) 3% normal neem foliage in concentrate, (3) 6% normal neem foliage in concentrate, (4) 3% purple neem foliage in concentrate and (5) 6% purple neem foliage in concentrate. The results show that the goats that were fed 6% purple neem foliage in concentrate had a higher (p < 0.01) feed intake gDM/d, %BW, g/kgBW^0.75, nutrient intake, nutrient digestion, final weight, weight change and ADG than did the goats that were fed 3% purple neem foliage in concentrate, 3% normal neem foliage in concentrate, 6% normal neem foliage in concentrate and control treatment. The feeding of 6% purple neem foliage in concentrate had higher (p < 0.01) N intake, N urine, N digestion, N digestion (%), N retention and N retention (%) than the other treatments. The goats receiving 6% purple neem foliage in concentrate had no negative effect (p < 0.01) on pH but had a higher (p < 0.01) level of ammonia nitrogen, BUN, acetic acid, propionic acid, ratio of acetic acid to propionic acid and total VFA at 2 and 4 h after feeding compared to the other treatments. The effect of anthocyanin-rich 6% purple neem foliage was shown to be higher than the other treatments (p < 0.01) for total bacteria, Butyrivibrio fibrisolvens, Fibrobacter succinogenes, Ruminococcus albus, Ruminococcus flavefaciens and Streptococcus bovis at 2 and 4 h after feeding. The goats fed 6% purple neem foliage displayed higher (p < 0.01) levels of total antioxidant (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPX), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and catalase (CAT) antioxidant activity in plasma at 2 and 4 h after feeding. The goats fed 6% purple neem foliage had lower (p < 0.01) protozoa methanogen and malondialdehyde (MDA) at 2 and 4 h after feeding. In developing growing goats, the introduction of anthocyanin-rich purple neem foliage boosted plasma antioxidant capacity, improved rumen volatile fatty acids and caused a shift in the structure and relative abundance of the ruminal microbial community.

The purpose of this experiment was to investigate the effect of Purple Neem foliage as a feed supplement on nutrient apparent digestibility, nitrogen utilization, rumen fermentation, microbial population, plasma antioxidants, meat quality and fatty acid profile of goats. Eighteen Boer male goats (approximately 20 ± 2 kg body weight; mean ± standard deviation (SD)) were randomly allocated into three treatments. All goats were fed a 60 d daily feeding with three treatments: (1) control, (2) 3% Purple Neem foliage (PNF) + 3% sunflower oil (SFO) in concentrate, and (3) 6% Purple Neem foliage (PNF) + 3% sunflower oil (SFO) in concentrate. The findings indicate that goat feed containing 6% PNF + 3% SFO in concentrate increased feed consumption, nutrient intake, nutrient apparent digestibility and nitrogen utilization compared to the goat feed at 3% PNF + 3% SFO and the control group. The feeding of goats with 6% PNF + 3% SFO in concentrate resulted in high ammonia nitrogen, BUN, acetic acid, propionic acid, butyric acid, and the total VFA levels were increased at 2 and 4 h after feeding (p < 0.01). The individual microbial population with 6% PNF + 3% SFO had higher (p < 0.01) total bacteria, higher Butyrivibrio fibrisolven, Fibrobacter succinogenes, Ruminococcus albus, Ruminococcus flavefacises, and Streptococcus bovis, decreased protozoa and methanogen levels at 2 and 4 h after feeding. The antioxidant in plasma indices varied, with 6% PNF + 3% SFO having higher total antioxidant (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPX), 2, 2-diphenyl-1-picrylhydrazyl (DPPH), and catalase (CAT) antioxidant activity and lower malondialdehyde (MDA) in plasma at 2 and 4 h after feeding. Additionally, goat fed 6% PNF + 3% SFO can improve meat quality by lowering drip loss, cooking loss, shear force, and saturated fatty acid as well as increase the fatty acid profile (monounsaturated and polyunsaturated fatty acids) in goat meat. Our findings suggest that Purple Neem foliage might be an excellent alternative additive for goat feed.

Freshwater scarcity has driven interest in culturing euryhaline species such as Nile tilapia (Oreochromis niloticus) in saline systems for sustainable aquaculture. This study examined the combined effects of dietary NaCl (2.5 % and 5.0 %) and water salinity (0, 15, 25 ppt) on tilapia muscle metabolome and meat quality using ¹H NMR metabolomics. Fish fed 5.0 % NaCl at higher salinities showed reduced muscle protein, increased salt, elevated TBARS, and lower TVB-N (P < 0.05). Under these conditions, water-holding capacity improved, while hardness and chewiness decreased, suggesting softer texture. Sensory evaluation showed no differences in consumer acceptance (P > 0.05). Metabolomics revealed ten key metabolites (e.g., carnosine, tyrosine, betaine, glycogen, lactate) and seven enriched pathways linked to osmoregulation and energy metabolism. Multivariate analyses indicated dietary salt exerted greater influence than water salinity, highlighting the need for feed adaptation. Overall, results demonstrate physiological trade-offs of salinity adaptation and identify potential biomarkers for meat quality in saline aquaculture.