Zhenzhu Sun

Effects of dietary dandelion extracts on growth performance, body composition, plasma biochemical parameters, immune responses and disease resistance of juvenile golden pompano Trachinotus ovatus

Abstract The present study was conducted to investigate the effects of dietary dandelion extracts (DE) supplementation on growth performance, feed utilization, body composition, plasma biochemical indices, immune responses, hepatic antioxidant abilities, and resistance to the pathogen Vibrio harveyi in Trachinotus ovatus. A basal diet supplemented with DE at 0, 0.50, 1.00, 2.00, 4.00 and 10.00 g kg−1 were fed to golden pompano for 8 weeks. The study indicated that dietary supplementation with DE could significantly improve final body weight (FBW), weight gain rate (WGR), specific growth rate (SGR), feed efficiency ratio (FER), feed intake (FI), protein efficiency ratio (PER) and protein deposit rate (PDR) (P < 0.05). The highest FBW, WGR, SGR, FI and PDR were observed in fish fed 1.00 g kg−1 dietary DE (P < 0.05). The highest FER and PER were recorded at 0.50 g kg−1 dietary DE (P < 0.05). Condition factor, viscerosomatic index, hepatosomatic index and survival were not significantly different among all groups. Fish fed 1.00 g kg−1 dietary DE showed significant increase in plasma total protein, complement 4 content and alkaline phosphatase, lysozyme, glutathione reductase (GSR) activity, but significant decrease in triglyceride, low density lipoprotein cholesterol, malondialdehyde (MDA) content and aspartate aminotransferase activities compared to the control group (P < 0.05). Hepatic antioxidant enzymes (SOD, T‐AOC, CAT, GSH‐Px, GSR) significantly increased whereas MDA content significantly decreased in fish fed 1.00 g kg−1 DE supplement (P < 0.05). After challenge with Vibrio harveyi, significant higher post‐challenge survival was observed in fish fed DE supplement (P < 0.05). These results indicated that golden pompano fed a diet supplemented with DE (especially at 1.00 g kg−1 of fed supplement) could significantly promote its growth performance, feed utilization, body protein deposit, immune ability, hepatic and plasma antioxidative enzyme activities and improve its resistance to infection by Vibrio harveyi. HighlightsDietary supplementation with dandelion extracts significantly improved growth performance in golden pompano.Dietary supplementation with dandelion extracts significantly enhanced immunity in golden pompano.Dietary supplementation with dandelion extracts significantly increased survival after Vibrio harveyi challenge.

Effects of dietary ginkgo biloba leaf extract on growth performance, plasma biochemical parameters, fish composition, immune responses, liver histology, and immune and apoptosis-related genes expression of hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀) fed high lipid diets

ABSTRACT For thousands of years, leaves from the Ginkgo biloba tree have been a common treatment in Chinese medicine. The present study was conducted to investigate the effects of dietary ginkgo biloba leaf extract (GBE) supplementation on growth performance, plasma biochemical parameters, fish composition, immune responses, liver histology, and immune and apoptosis‐related genes expression of hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀) fed high lipid diets. A basal diet supplemented with GBE at 0, 0.50, 1.00, 2.00, 4.00 and 10.00 g kg−1 was fed to hybrid grouper for 8 weeks. The study indicated that dietary GBE did not improve growth performance and feed utilization but it reduced intraperitoneal fat rate. There were no significant differences in condition factor, viscerosomatic index, hepatosomatic index, spleen index, relative gut length, food intake, protein deposit rate and survival among all groups (P > 0.05). Dietary supplementation with 0.50–4.00 g GBE kg−1 diets effectively increased plasma HDL content and decreased plasma GLU, LDL and TG content in fish. Furthermore, dietary GBE had a significant effect on moisture, crude protein and lipid in the liver, and protein in the whole body of fish (P < 0.05). Dietary supplementation with 0.50–1.00 g GBE kg−1 diets effectively decreased occurrence rates of the hepatocyte swelling, hepatocyte vacuolization, and nuclei shifting to the cellular periphery cytoplasmic vacuolization, meanwhile hepatic antioxidant enzymes (SOD, CAT and T‐AOC) activities significantly increased whereas MDA content significantly decreased in fish fed diets supplemented with GBE (P < 0.05). Moreover, dietary GBE up‐regulated the expression of antioxidant genes (CAT, GPx and GR), immune‐related genes (MHC2 and TLR3) and anti‐inflammatory cytokines (IL‐10 and TGF‐&bgr;1), while dietary supplementation with 0.50–4.00 g GBE kg−1 diets down‐regulated apoptosis‐related genes (p53, caspase‐9, caspase‐8 and caspase‐3) expression in the head kidney of hybrid grouper. These results indicated that hybrid grouper fed diets supplemented with GBE did not improve growth performance and feed utilization but it had hypolipidemic effects, improved hepatic antioxidant status, maintained normal liver histology and preserved liver function, increased immune‐related genes expression and decreased apoptosis‐related genes expression in the head kidney of hybrid grouper. HighlightsDietary ginkgo biloba leaf extract (GBE) had hypolipidemic effects in hybrid grouper fed high lipid diets.Dietary GBE improved hepatic antioxidant ability and maintain normal liver histology.Dietary GBE increased immune‐related genes expression and decrease apoptosis‐related genes expression.

Effects of dietary hawthorn extract on growth performance, immune responses, growth- and immune-related genes expression of juvenile golden pompano (Trachinotus ovatus) and its susceptibility to Vibrio harveyi infection

ABSTRACT The present study was conducted to investigate the effects of dietary hawthorn extract (HTE) supplementation on growth performance, immune responses, hepatic antioxidant abilities, growth‐ and immune‐related and heat shock protein genes expression and resistance to the pathogen Vibrio harveyi in Trachinotus ovatus. A basal diet supplemented with HTE at 0 (Diet 1), 0.50 (Diet 2), 1.00 (Diet 3), 2.00 (Diet 4), 4.00 (Diet 5) and 10.00 (Diet 6) g kg−1 were fed to golden pompano for 8 weeks. The highest final body weight, weight gain rate, specific growth rate, feed efficiency ratio and protein efficiency rate were observed in fish fed Diet 2 (P < 0.05). Dietary HTE significantly increased plasma complement 3, complement 4 and immunoglobulin M content (P < 0.05). Hepatic antioxidant enzymes (SOD, T‐AOC, CAT, GPx, GR) significantly increased (P < 0.05), whereas MDA content decreased first and then increased in fish fed HTE supplement. After challenge with Vibrio harveyi, significant higher post‐challenge survival was observed in fish fed Diet 2 and Diet 3 than the control group (P < 0.05). Transcription levels of growth‐related genes (IGF‐I and IGF‐II) were significantly up‐regulated in fish fed HTE supplement (P < 0.05), whereas HSP70 and HSP90 mRNA levels were significantly down‐regulated (P < 0.05). With respect to immune‐related genes, such as tumour necrosis factor‐alpha (TNF‐&agr;), interleukin‐8 (IL‐8) and inhibitor protein &kgr;B&agr; (I&kgr;B‐&agr;), upregulation was observed in the liver of fish fed with the diet supplemented with HTE. In contrast, the expression of antioxidant enzyme genes (CAT, GPx, MnSOD and Keap1) and cytokines (IL‐10, TGF‐&bgr;1 and TOR) was downregulated. These results indicated that golden pompano fed a diet supplemented with 0.50 g kg−1 HTE could significantly promote growth performance and growth‐related genes expression, strengthen immunity, and improve hepatic antioxidative abilities and resistance to Vibrio harveyi infection. HighlightsDietary HTE improved growth performance and immunity in golden pompano.Dietary HTE significantly increased survival after Vibrio harveyi challenge.

Effects of dietary Panax notoginseng extract on growth performance, fish composition, immune responses, intestinal histology and immune related genes expression of hybrid grouper (Epinephelus lanceolatus ♂ × Epinephelus fuscoguttatus ♀) fed high lipid diets

ABSTRACT Growth, plasma biochemical parameters, fish composition, immune parameters, intestinal histology, and expressions of immune‐related genes were examined in hybrid grouper (Epinephelus lanceolatus ♂ × Epinephelus fuscoguttatus ♀) that fed respectively six diets containing Panax notoginseng extract (PNE) at 0, 0.5, 1, 2, 4, and 10 g kg−1 after 8 weeks. Results indicated that dietary PNE significantly improved growth, feed efficiency ratio, protein efficiency ratio, and protein deposit rate, and significantly increased crude protein and crude lipid levels of whole body and crude protein level of muscle. Dietary PNE significantly increased plasma total protein, alkaline phosphatase, immunoglobulin, complement 3 and complement 4 contents, but significantly decreased cholesterol, triglyceride, glucose, and low density lipoprotein cholesterol contents. Furthermore, dietary PNE increased villus length and muscle thickness in foregut, midgut, and hindgut, activities of hepatic superoxide dismutase and total antioxidant capacity, and increased the expression levels of immune related genes (IL‐10, TGF‐&bgr;1, TOR, MHC2 and TLR3) in the head kidney and the expression levels of antioxidant genes (CAT and GR) in fish that fed PNE at 0.5–4 g kg−1. In conclusion, grouper fed high lipid diets supplemented with PNE at 0.5–10 g kg−1 improved growth, feed utilization, blood immune parameters, hepatic antioxidant status, intestine morphology and expression levels of immune related genes in the head kidney. HIGHLIGHTSDietary administration of 0.5–10 g kg−1 Panax notoginseng extract (PNE) improved growth performance in hybrid grouper.Dietary PNE had several positive effects on plasma biochemical and immune responses of fish.Diets with 0.5–4 g kg−1 PNE improved hepatic antioxidant ability and intestinal histology in fish.

Effects of dietary dandelion extract on intestinal morphology, antioxidant status, immune function and physical barrier function of juvenile golden pompano Trachinotus ovatus

ABSTRACT Intestinal morphology, antioxidant status, immune function and tight junction proteins mRNA expression were examined in golden pompano (Trachinotus ovatus) that fed respectively six diets containing dandelion extracts (DE) at 0, 0.5, 1, 2, 4 and 10gkg−1 after 8 weeks feeding. The study indicated that dietary DE significantly improved intestinal antioxidant abilities by increasing SOD, CAT, T‐AOC activities and up‐regulating intestinal cat, gpx mRNA levels, but by decreasing MDA content and down‐regulating intestinal keap1 mRNA levels in golden pompano. Meanwhile, dietary DE improved intestinal morphology, suggesting that enhances intestinal digestion and absorption, by increasing muscle thickness, villus length, villus width and villus number in the foregut and hindgut; as well as villus number, villus width and muscle thickness in the midgut (P<.05). Dietary DE enhanced intestinal barrier function by increasing intestinal zo‐1 and occludin mRNA levels, but by decreasing the mRNA levels of claudin‐12 and claudin‐15. Furthermore, dietary DE improved intestinal immunity via increasing goblet cells numbers and regulating expression of immune‐related genes. In conclusion, dietary DE supplementation promoted intestine health by improving intestine morphology, immunity, antioxidant abilities and intestinal barrier in golden pompano. HIGHLIGHTSDietary dandelion extracts (DE) enhanced intestinal digestion and absorption by improving intestinal morphology of golden pompano.DE regulated the tight junction proteins mRNA levels, suggesting improved intestinal physical barrier.DE improved intestinal antioxidant abilities by increasing antioxidant enzyme activities.

The hepatoprotective effects of Radix Bupleuri extracts against D-galactosamine/lipopolysaccharide induced liver injury in hybrid grouper (Epinephelus lanceolatus♂ × Epinephelus fuscoguttatus♀)

Abstract The present study is aiming at evaluating the hepatoprotective of Radix Bupleuri extracts (RBE) on the d‐galactosamine/lipopolysaccharide (D‐GalN/LPS) induced liver injury of hybrid grouper in vitro and in vivo. In vitro, RBE (0, 200, 400 and 800 &mgr;g/ml) was added to the hybrid grouper primary hepatocytes before (pretreatment) the incubation of the hepatocytes with D‐GalN (20 mM) plus LPS (1 &mgr;g/ml) in the culture medium. RBE at concentrations of 200, 400 and 800 &mgr;g/ml significantly improved cell viability and inhibited the elevation of TNF‐&agr;, IL‐1&bgr; and IL‐6 and significantly down‐regulated the caspase‐3, caspase‐9 and P53 mRNA levels. In vivo administration of RBE at the doses of 0, 200, 400, 800 and 1600 mg/kg in the diet for 8 weeks prior to D‐GalN (500 mg/kg) and LPS (20 &mgr;g/kg) intoxication. The study indicated that the RBE not only ameliorated liver injury, as evidenced by well‐preserved liver architecture, but also significantly increased hepatic antioxidant enzymes activities in the D‐GalN/LPS‐induced liver injury animal model. Further demonstrating the protective effects of the RBE, we found that pretreatment with the RBE up‐regulated the expression of antioxidant genes (GPx and MnSOD), while down‐regulated apoptosis‐related genes (caspase‐3, caspase‐9 and P53), immune related genes (MHC2 and TLR3) and pro‐inflammatory cytokines (TOR and IKK&agr;) mRNA expression in the liver of hybrid grouper. In brief, the present study showed that RBE can protect hepatocyte injury induced by D‐GalN/LPS through elevating antioxidant enzyme activity and suppressing apoptosis and immune inflammatory responses. The results support the use of RBE as a hepatoprotective in fish. HighlightsIn vitro and in vivo successfully established D‐GalN/LPS induced hepatocytes or liver injury experimental models in fish.Radix Bupleuri extracts (RBE) significantly improved cell viability and apoptosis from hepatocytes induced by D‐GalN/LPS.Diets with 400–800 mg/kg RBE improved hepatic antioxidant ability and immune responses induced by D‐GalN/LPS in fish.