Dietary red macroalgae (Halopithys incurva) improved systemic an mucosal immune and antioxidant parameters and modulated related gene expression in zebrafish (Danio rerio).

In the present study, the effects of dietary Halopithys incurva, a red macroalgae species, (0.25, 0.50, 1%) on whole-body serum and skin mucus immune system, antioxidant system and expression of various genes in zebrafish were investigated. At the end of the 8-week study, total protein, total immunoglobulin and lysozyme activities in whole-body serum and skin mucus increased in fish fed H. incurva (P < 0.05). While an increase was observed in superoxide dismutase (SOD), Catalase (CAT) and glutathione peroxidase (GPx) which are antioxidant enzyme activities in whole-body serum and skin mucus, a decrease in malondialdehyde (MDA) levels was detected (P < 0.05). All of the immune-related genes examined, such as Interleukin-1 beta (IL-1ß), Tumor necrosis factor-alpha (TNF-α), Interferon-gamma (INF- γ), were upregulated by the addition of 0.5% H. incurva (P < 0.05). While SOD and GPx, which are antioxidant enzyme-related genes, were remarkably upregulated in macroalgae fed fish (P < 0.05), no change was observed in CAT gene expression (P > 0.05). Based on the results of this study, it is considered that the addition of 0.5% H. incurva to the diets of commercially farmed fish will increase their immune and antioxidant defences and may contribute to the aquaculture sector for more sustainability.

Effects of dietary fern (Adiantum capillus-veneris) leaves powder on serum and mucus antioxidant defence, immunological responses, antimicrobial activity and growth performance of common carp (Cyprinus carpio) juveniles.

A 56-day research was performed to examine the influence of graded levels (0 (control), 0.5, 1 and 2%) of Fern (Adiantum capillus-veneris) leaves powder (FLP) in diet on immune competence and growth of common carp (Cyprinus carpio, initial weight = 20 g). The serum total immunoglobulins content and lysozyme activity in the 1 and 2% FLP groups remarkably increased compared to the other groups (P < 0.05). The skin mucosal lysozyme activity enhanced with increasing dietary FLP level in a dose-response manner. Fish fed on the FLP-supplemented diets had higher skin-mucosal superoxide dismutase activity than the control (P < 0.05). However, serum antioxidant enzymes were not affected by dietary fern (P > 0.05). The serum bactericidal activity against human and fish pathogens increased with enhancing the FLP level in diet against Staphylococcus aureus, Escherichia coli (EHEC ATCC 43895), Escherichia coli (CI), Pseudomonas aeruginosa, Klebsiella pneumonia and Aeromonas hydrophila. The serum antibacterial activity against Yersinia ruckeri in the 2% FLP group was higher than the other treatments. Furthermore, the serum bactericidal activity against P. aeruginosa (ATCC 27853) only observed in fish fed on the 1 and 2% FLP-supplemented diets. The skin mucosal bactericidal activity and inhibitory effects increased with enhancing the FLP level in diet against E. coli, K. pneumonia, Y. ruckeri and A. hydrophila in a dose response manner. Moreover, the skin mucosal bactericidal activity against S. aureus only observed in fish fed on 1 and 2% FLP-supplemented diets. The weight gain values in the 1 and 2% FLP groups were higher than the other treatments (P < 0.05). Feed conversion ratio (FCR) improved with increasing FLP level in diet in a dose-response manner (P < 0.05). By considering serum and mucosal bactericidal activities against different pathogenic bacteria, the supplementation of 2% FLP in diet is recommended for C. carpio during grow-out phase.

Antimicrobial Resistance and Virulence-Associated Genes of Campylobacter spp. Isolated from Raw Milk, Fish, Poultry, and Red Meat.

This study was designed and conducted to evaluate the frequency, antimicrobial resistance, and presence of six virulence-associated genes among thermophilic Campylobacters isolated from raw milk, poultry (chicken, turkey, and duck), fish, cattle, and sheep meat. Out of 590 samples, which were recovered from different origins, 141 (23.9%) samples were positive for Campylobacters. Campylobacter spp. was isolated in 40.8% (106/260), 14% (28/200), and 8.7% (7/80) of poultry meat, red meat, and milk samples, respectively. Antimicrobial susceptibility test indicated a high frequency of resistance to ciprofloxacin, tetracycline, and nalidixic acid among the isolates. Furthermore, prevalence of waaC, ciaB, and pldA genes were 91.7%, 86.7%, and 80.8%, respectively; and, none of the isolates harbored both wlaN and cgtB genes, simultaneously. Moreover, there was a weak correlation between antibiotics resistance and presence of the pathogen genes. However, the existence of Campylobacter spp. isolates in food animal products, with high resistance to antibiotics and several virulence gene possessions, is alarming and increases the attention to the widespread use of antibiotics.

Study of Hypoglycemic, Hypocholesterolemic and Antioxidant Activities of Iranian Mentha Spicata Leaves Aqueous Extract in Diabetic Rats.

This study was conducted to evaluate the hypoglycemic, hypocholesterolemic and antioxidant properties of Mentha spicata (Labiateae) leaves aqueous extract (MSLA) in alloxan-induced diabetic rats. In this study, hyperglycemia was induced in male rats by intraperitoneal injection of alloxan monohydrate (150 mg/kg). The aqueous extract of M. spicata was orally administered at a dose of 300 mg/kg body weight to diabetic rats for 21 days and the effects were compared with glibenclamid (2 mg/kg). Fasing blood sugar (FBS), body weight, lipid profile and serum malondialdehyde (MDA) were monitored at 0, 7, 14 and 21 days after induction of diabetes. Total phenol contents (TP) and reducing power (RP) were also evaluated. TP and RP of aqueous extract were 2.763 ± 0.39 mg Galic acid/gr and 0.026 ± 0.001 EC50 mg/mL, respectively. The LD50 of the extract was found to be ˃ 1500 mg/kg. The administration of M. spicata aqueous extract produced a significant reduction (P˂0.01) in FBS, total cholesterol, triglyceride, low density lipoprotein-cholesterol and MDA (101.83 ± 4.33, 95.66 ± 4.75, 89.83 ± 5.26, 26.20 ± 5.10 mg/dl and 1.53 ± 0.61 µmol/l, respectively) in diabetic rats. These effects were comparable with the effects of standard antidiabetic drug (glibenclamide). The results of the investigation indicated that M. spicata leaf aqueous extract possess hypoglycemic, hypocholesterolemic and antioxidant properties in diabetic rats. Therefore, this study suggest a promising use of it for treatment of diabetes.