Dietary effect of grape (Vitis vinifera) seed extract mitigates hepatic disorders caused by oxidized fish oil in rainbow trout (Oncorhynchus mykiss).

The major goal of this study was to determine the effect of grape seed extract (GSE) on liver damage in rainbow trout (Oncorhynchus mykiss) that was caused by the consumption of dietary oxidized fish oil (OFO). Rainbow trout were fed six different experimental diets coded OX-GSE 0 (OFO diet), OX-GSE 1 (OFO and 0.1% GSE), OX-GSE 3 (OFO and 0.3% GSE), GSE 0 (fresh fish oil and 0.0% GSE), GSE 1 (fresh fish oil and 0.1% GSE), and GSE 3 (fresh fish oil and 0.3% GSE) for 30 days. The lowest % hepatosomatic index (HSI) result was calculated in fish fed with OX-GSE 0 and the highest HSI was determined in fish fed with GSE 1 diets (p < 0.05). Histopathologically, hydropic degeneration in hepatocytes significantly increased OX-GSE 0 and GSE 3 compared to GSE 1 diets (p < 0.05). Deposition of lipid droplets in hepatocytes was significantly increased in OX-GSE 0 and OX-GSE 3 groups than others (p < 0.05). Liver biochemistry parameters such as superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA) were significantly affected by OX and GSE treatments (p < 0.05). There were significant differences in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) among the liver enzymes analyzed in serum in OX and GSE (p < 0.05), meanwhile no difference was observed in lactate dehydrogenase (LDH) values between groups (p > 0.05). In conclusion, liver biochemistry and histopathology of rainbow trout consuming diets containing oxidized fish oil were negatively affected. However, it was determined that the supplementation of 0.1% GSE to the diet had a significant ameliorative role in these adverse effects.

Hot pepper (Capsicum sp.) oil and its effects on growth performance and blood parameters in rainbow trout (Oncorhynchus mykiss).

The authors studied the effect of hot pepper (capsicum sp.) oil on the growth performance and blood parameters in rainbow trout fed. Hot pepper oil was added to rainbow trout feeds at the rates of HPO 0‰ (0 mg/kg) (control), HPO 1‰ (1 mg/kg), HPO 2‰ (2 mg/kg), HPO 4‰ (4 mg/kg) and HPO 6‰ (6 mg/kg), and the fish were fed with experimental feeds for 60 days. The group fed with HPO 4‰ showed the highest percentage growth rate and the lowest feed conversion rate. Our results showed the significant differences serum biochemical parameters, a decrease of serum liver enzymes, glucose, cholesterol and triglyceride levels and an increase of total protein and albumin levels compared with the control. The use of HPO 1‰ in rainbow trout showed a positively affects the growth performance, haematological and serum biochemical parameters.[Formula: see text].

Effects of bergamot (Citrus bergamia) peel oil-supplemented diets on growth performance, haematology and serum biochemical parameters of Nile tilapia (Oreochromis niloticus).

The present study investigated the effects of dietary Citrus bergamia peel oil (CBO) on growth performance, haematological and serum biochemical responses of Nile tilapia, Oreochromis niloticus. Volatile content of C. bergamia peel oil used in study was detected with GC/MS. The 99.47% of the analysed volatile components were identified in decreasing quantities as limonene, linalool and linalyl acetate. The experimental fish were divided into four groups stocked into triplicate tanks (20 fish/tank), and fed daily with an additive-free basal diet containing 0% (CBO0), 0.5% (CBO0.5), 1.0% (CBO1), 2.0% (CBO2) of bergamot peel oil for an 8-week period. Results showed that dietary bergamot peel oil especially at 0.5 g 100 g-1 significantly increased growth performance of fish (p < 0.05). The levels of haemoglobin and haematocrit significantly increased in fish fed with CBO0.5 and CBO1 compared with the CBO0-fed group (p < 0.05), despite no significant difference was observed in CBO2 group (p > 0.05). Highest haematocrit value was found in the CBO0.5 group compared with the control group. The serum glucose of the fish fed with CBO0.5 and CBO1 feeds decreased significantly compared with the control group (p < 0.05). The highest total protein, lowest cholesterol and triglyceride in serum were observed in fish fed with bergamot oil-supplemented groups. According to the results, it was revealed that 0.5% bergamot oil supplementation to Nile tilapia diets optimizes the growth performance, feed utilization and health status related with blood parameters of the fish.