Dietary cinnamaldehyde nanoemulsion boosts growth and transcriptomes of antioxidant and immune related genes to fight Streptococcus agalactiae infection in Nile tilapia (Oreochromis niloticus).

The present study was conducted to investigate the effects of dietary cinnamaldehyde nanoemulsion (CNE) on growth, digestive activities, antioxidant and immune responses and resistance against Streptococcus agalactiae (S. agalactiae) in Nile tilapia. Four experimental diets were formulated containing CNE at levels of 0, 100, 200 and 300 mg/kg diet for 12 weeks. At the end of the experiment, all fish were challenged by S. agalactiae. The results showed that the final body weight was increased in fish groups fed 200 and 300 mg CNE/kg diet by 18.4 and 17.2% with respect to the control group. Moreover, feed conversion ratio and digestive enzymes' activities were improved in groups fed 200 and 300 then 100 mg of dietary CNE/kg diet. Groups fed CNE exhibited a significant increase in serum immune-related parameters when compared with control group. Additionally, the hypocholesterolemic effects was achieved after CNE feeding unlike the control group in a dose dependent manner. With increasing dietary CNE levels, genes expression of cytokines and antioxidant enzymes were upregulated. Less severe adverse clinical symptoms and respectable cumulative mortalities associated with S. agalactiae infection were observed in fish fed CNE. To our knowledge, this study was the first offering a protective effect of CNE against S. agalactiae infection in Nile tilapia with a maximum down-regulation of cylE and hylB virulence genes expression noticed in group fed 300 mg of CNE/kg diet (up to 0.10 and 0.19- fold, respectively). Therefore, the present study recommended that an incorporation of CNE at level of 300 mg/kg diet for Nile tilapia could promote their growth, enhance their immunity and antioxidant status and provide protection against virulent S. agalactiae.

Changing dietary n-6:n-3 ratio using different oil sources affects performance, behavior, cytokines mRNA expression and meat fatty acid profile of broiler chickens.

Typical formulated broiler diets are deficient in n-3 poly-unsaturated fatty acids (PUFA) due to widening n-6:n-3 PUFA ratio which could greatly affect performance, immune system of birds and, more importantly, meat quality. This study was conducted to evaluate the effect of modifying dietary n-6:n-3 PUFA ratio from plant and animal oil sources on performance, behavior, cytokine mRNA expression, antioxidative status and meat fatty acid profile of broiler chickens. Birds (n = 420) were fed 7 diets enriched with different dietary oil sources and ratios as follows: sunflower oil in control diet (C); fish oil (FO); 1:1 ratio of sunflower oil to FO (C1FO1); 3:1 ratio of sunflower oil to fish oil (C3FO1); linseed oil (LO); 1:1 ratio of sunflower oil to linseed oil (C1LO1); 3:1 ratio of sunflower oil to linseed oil (C3LO1), resulting in dietary n-6:n-3 ratios of approximately 40:1, 1.5:1, 4:1, 8:1, 1:1, 2.5:1 and 5:1, respectively. The best final body weight, feed conversion ratio as well as protein efficiency ratio of broilers were recorded in the C1FO1 and C1LO1 groups. Compared with the control group, the dressing percentage and breast and thigh yield were highest in the C1FO1 and C1LO1 groups. Narrowing the dietary n-6:n-3 ratio increased (P < 0.05) n-3 PUFA content of breast meat. Moreover, the breast meat contents of eicosapentaenoic acid and docosahexaenoic acid increased (P < 0.05) with increasing dietary FO whereas α-linolenic acid content was higher with LO supplementation. Also, enriching the diets with n-3 PUFA from FO and LO clearly decreased (P < 0.05) serum total cholesterol, triglycerides and very low-density lipoproteins and enhanced antioxidative status. The feeding frequency was decreased (P < 0.05) in the C1FO1 and C1LO1 groups. Likewise, n-3 PUFA-enriched diets enhanced the frequency of preening, wing flapping and flightiness. Animal oil source addition, compared to plant oil, to broiler diets enhanced the relative mRNA expression of interferon gamma, interleukin-1 beta, interleukin-2 and interleukin-6 genes, especially at low n-6:n-3 ratios. This study has clearly shown that narrowing n-6:n-3 ratio through the addition of FO or LO improved performance and immune response of broilers and resulted in healthy chicken meat, enriched with long chain n-3 PUFA.

Peppermint essential oil alleviates hyperglycemia caused by streptozotocin- nicotinamide-induced type 2 diabetes in rats.

The prevalence of diabetes mellitus is steadily growing throughout the world. Traditional medicine has an excellent potential in the treatment of diabetes mellitus. The present study was undertaken to evaluate the potential antidiabetic effect of peppermint essential oil (PEO) on streptozotocin (STZ) and nicotinamide induced diabetic rats. Diabetes was induced in rats fasting overnight by the intraperitoneal administration of nicotinamide followed by a single dose of STZ. After 72h, two groups of diabetic rats were treated with different doses of PEO (40 and 80mg/kg BW) respectively and one group was treated with the standard hypoglycemic agent glibenclamide. The levels of blood glucose, serum insulin, and C-peptide were estimated. The markers of oxidative stress were quantified. The samples from liver and pancreas were collected for histological evaluation. Immunohistochemical tests were carried out to determine the expression of Bcl-2 and insulin in the liver and pancreas, respectively. After the treatment with PEO, it was observed that anemia resulting from diabetes was rectified, the counts of leukocytes and platelets, which decreased during diabetes, were increased, the levels of blood glucose were decreased and those of serum insulin and C-peptide were increased. The administration of PEO also enhanced the antioxidant status in the treated rats. The histological analysis revealed regeneration of the hepatic and pancreatic tissues and the extent of degenerative changes were reduced. The immunohistochemical examination revealed upregulation in the expression of Bcl-2 and insulin. These findings demonstrated the potential antidiabetic capability of PEO.