Dietary supplementation of guanidinoacetic acid improves growth, biochemical parameters, antioxidant capacity and cytokine responses in Nile tilapia (Oreochromis niloticus).

A total of 180 unsexed Nile Tilapia fish (initial weight, 21 g) fed isonitrogenous (32%), isocaloric (3000 kcal/kg) diets containing different levels of guanidinoacetic acid (GAA) at levels of (GAA1, 0.06%, GAA2, 0.12%, GAA3, 0.18%); for 60 days. Results showed higher final body weight (FBW) and body weight gain (BWG) in groups supplemented with different levels of GAA. Specific growth rate (SGR) was the highest in groups supplemented with 0.12% and 0.18% GAA. Lipid % of whole-body composition was higher in all groups excluding GAA3 group. Serum creatine kinase (CK) activity, cholesterol, and creatinine levels showed a marked significant (P < 0.05) increase in all GAA supplemented groups compared to the control one. Triglycerides level demonstrated a higher elevation (P < 0.05) in both GAA2 and GAA3 supplemented groups. No significant observed in total protein, albumin, globulin, and A/G ratio. Lipid peroxidation marker (malondialdehyde/MDA) is markedly decreased along with a significant increase of superoxide dismutase (SOD), reduced glutathione (GSH), and nitric oxide (NO) levels in both GAA2 and GAA3 compared to other groups. Similarly, interleukin 1ß (IL-1ß) and tumor necrosis factor (TNF-α) gene expression levels were downregulated along with upregulation of transforming growth factor ß1 (TGF-ß1) at higher GAA levels, particularly at 0.18%. Our findings give important insights for the growth promoting, antioxidant and immunomodulatory effects of GAA supplemented diet particularly at level of 0.18%.

Effect of dietary supplementation of calcium butyrate on growth performance, carcass traits, intestinal health and pro-inflammatory cytokines in Japanese quails.

The objective of the present study was to evaluate the potential effect of dietary calcium butyrate on growth performance, carcass traits and gut health in Japanese quails. In total, 320 one-day-old Japanese quails were randomly assigned to 4 equal treatments, with 8 replicates of 10 Japanese quails, for 4 weeks. The Japanese quails in control treatment were fed control diet whereas in the other treatments the Japanese quails were fed diet supplemented with calcium butyrate at 0.3, 0.5 and 0.7 g/kg diet. Data concerning performance measurements were recorded weekly. In addition, eight Japanese quails (one/replicate) from each treatment were selected randomly for serum collection to measure pro- and anti-inflammatory cytokines. Pooled faecal samples from each replicate of each treatment were also collected at three time points (0, 2 and 4 weeks) for count E. coli and C. perfringens. The results showed that after 7 days of the experimental period, Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg showed a greater (p < .05) body weight and a favourable (p < .05) feed conversion ratio than the other treatments. Moreover, serum superoxide dismutase and catalase activities were increased (p < .05) in Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg. Calcium butyrate supplementation at 0.7 g/kg was associated with reduction (p < .05) in TNF-α, IL-6 and IL1-ß, while IL-10 was increased (p < .05). In addition, after 2 weeks of calcium butyrate supplementation, a reduction (p < .05) in E. coli and C. perfringens counts was observed in excreta of Japanese quails fed 0.5 and 0.7 g calcium butyrate/kg diets. It is concluded that calcium butyrate supplementation improves body weight gain, reduces E. coli and C. perfringens counts and has anti-inflammatory/anti-oxidant effect in Japanese quails.

Effect of dietary yeast nucleotide on antioxidant activity, non-specific immunity, intestinal cytokines, and disease resistance in Nile Tilapia.

The present study investigated the effects of dietary supplementation of yeast nucleotides on the hematology, antioxidant activity, non-specific immunity, expression of intestinal cytokines, and disease resistance in Nile Tilapia (Oreochromis niloticus). Fish weighing 42.90 ±â€¯0.14 g were randomly divided into four groups. Each group was set in triplicate (15 fish per replicate). Fish were fed on four dietary levels of yeast nucleotides (NTs) supplemented with the basal diet 0% (control), 0.05%, 0.15%, and 0.25% NTs. Significantly higher total serum protein, albumin, total serum globulin, total WBC counts, and lymphocyte and granulocyte contents were recorded in 0.25% NT group as compared to the control. The albumin/globulin ratio (A:G) showed a considerable decrease in the 0.25% NT group. The non-specific immune parameters; serum killing percentage, lysozyme activity, nitric oxide assay, IgM levels, and anti-protease activity, were significantly higher in the 0.25% NT group as compared to the control. Moreover, a 15-day feeding trial demonstrated improved results in terms of serum lysozyme activity, nitric oxide assay, IgM levels, and anti-protease activity than a 30-day feeding trial. A significant increase in the anti-oxidant status of O. niloticus was noticed, as reflected by increased superoxide dismutase and malondialdehyde activity in the serum of 0.25% NT group compared to the control, while glutathione peroxidase displayed a significant increase in all groups as compared to the control. The intestinal cytokines TGF-ß, IL-1ß, IL-10ß, and TNF-α mRNA levels showed a pattern of 0.25% NT > 0.15% NT > 0.05% NT > 0% NT, as relative to the control Ef-1α levels. The relative survival percentages of fish fed on yeast nucleotide-supplemented diets, as analyzed by exposure to Aeromonas sobria, were significantly better than the control group. In conclusion, dietary yeast nucleotide administration at 0.25% improved blood proteins, leukocytes, antioxidant activity, non-specific immunity, cytokine gene expression, and disease resistance of Nile Tilapia.

Narrow-band UVB effects on cutaneous vitamin D receptor expression and serum 25-hydroxyvitamin D in generalized vitiligo.

BACKGROUND/PURPOSE: Vitamin D has a role in variety of autoimmune diseases including vitiligo. Narrow-band UVB (NB-UVB) treatment of vitiligo might act through its effects on vitamin D and its receptor.This study is the first to elucidate NB-UVB effects on immunohistochemical vitamin D receptor (VDR) expression in generalized vitiligo and correlate it with serum vitamin D and repigmentation response. METHODS: Using immunohistochemistry, VDR expression was estimated in skin biopsies of 30 controls and 30 vitiligo patients; from vitiligo lesion, perilesional skin at baseline and from repigmented and nonresponding skin after 24 NB-UVB sessions. Baseline serum 25-hydroxyvitamin D [25(OH)D] was investigated and repeated after 24 NB-UVB sessions. RESULTS: Vitamin D receptor expression and serum 25(OH)D in controls were significantly higher compared to vitiligo patients. After NB-UVB therapy, there was a significant rise in VDR expression and serum 25(OH)D. VDR expression was significantly higher in repigmented skin compared to nonresponding lesion. Improvement in the clinical outcome score was associated with higher baseline VDR expression and higher serum 25(OH)D. CONCLUSIONS: NB-UVB phototherapy is associated with improved cutaneous VDR expression and vitamin D synthesis. Better repigmentation response to NB-UVB may be related to higher baseline VDR expression and its upregulation after phototherapy.

Effects of dietary acidifiers on growth, hematology, immune response and disease resistance of Nile tilapia, Oreochromis niloticus.

Organic acids or their salts can be used as feed additives in aquaculture. This study was conducted to evaluate the use of a mixture of formic acid, propionic acid and calcium propionate compared with oxytetracycline (OTC). A total of 720 apparently healthy Oreochromis niloticus fingerlings with an average body weight of 28.8 ± 0.14 g (mean ± SE) were randomly divided into four equal groups (G1, G2, G3and G4). G1 was fed a basal diet with no additive as the control group, while G2 and G3 were fed a formic and propionic acid/salt mixture in 1 and 2 g/kg, respectively. G4 was fed OTC (0.5 g/kg). Each group was subdivided into tow subgroups A and B (30 fish/subgroup) in triplicate. The first subgroup was used to evaluate growth performance, hematology and body composition for 60 d. The second subgroup was used to examine immunity, gut microbiota and resistance to infection for 30 d. At the end of the feeding period (60 d), G3 had significant improvements in final body weight (FBW), weight gain (WG), specific growth rate (SGR) and food conversion ratio (FCR) compared with other groups. The total erythrocyte count, hemoglobin content, platelet count, hematocrit, mean corpuscular hemoglobin and total leukocyte count were significantly increased in G3 and G2 compared with G1 and G4. Mean corpuscular volum, lymphocyte and neutrophil percentages had the highest significant improvement in G3. There were no significant differences among the groups in mean corpuscular hemoglobin concentration and monocyte percentage. The protein and fat contents of the whole body were the highest in G3. The widest inhibition zones against Aeromonas sobria were at the 30, 40 and 50% concentrations of acidifiers, which were equivalent to OTC (30 µg). G3 showed the lowest total gastrointestinal bacterial counts, followed by G2. After 15 and 30 d, G3 had the highest serum killing, lysozyme and nitric oxide activities. Serum lysozyme activity and nitric oxide assay had no significant difference between G1 and G2 after 30 d. The lowest immune parameters were recorded in G4. After 30 d, the highest expression of interleukin-1ß and tumor necrosis factor-alpha in the liver and kidney were found in G3. The best protection against challenged Aeromonas sobria was in G3, followed by G2 and G4. Dietary supplementation with a combination of formic acid, propionic acid and calcium propionate improves the performance of Nile tilapia.