Effects of dietary administration of Echinacea purpurea on growth indices and biochemical and hematological indices in rainbow trout (Oncorhynchus mykiss) fingerlings

Identification and characterization of immune-related microRNAs in hybrid snakehead(Channa maculata♀ × Channa argus♂)after treated by Echinacea purpurea (Linn.) Moench

Echinacea purpurea (Linn.) Moench (EP) is a globally popular herbal medicine, which showed effects on growth promotion, antioxidant and immunomodulatory activities in fish culture world widely. However, there are few studies about the effects on miRNAs by EP in fish. The hybrid snakehead fish (Channa maculate♀ × Channa argus ♂) was new important economic specie of freshwater aquaculture in China with high market value and demand while there were only a few reports about its miRNAs. To overview immune-related miRNAs of the hybrid snakehead fish and to further understand the immune regulating mechanism of EP, we herein constructed and analyzed three small RNA libraries of immune tissues including liver, spleen and head kidney of the fish with or without EP treatment via Illumina high-throughput sequencing technology. Results showed that EP can affect the immune activities of fish by the miRNA-regulated ways. Totally, 67 (47 up and 20 down) miRNAs in liver, 138 (55 up and 83 down) miRNAs in spleen, and 251 (15 up and 236 down) miRNAs in spleen were detected, as well as 30, 60, 139 kinds of immune-related miRNAs belonging to 22, 35 and 66 families of the three tissues respectively. The expressions of 8 immune-related miRNA family members were found in all the three tissues, including miR-10, miR-133, miR-22 and etc. Some miRNAs have been identified involved in the innate and adaptive immune responses, such as the miR-125, miR-138, and miR-181 family. Ten miRNA families with antioxidant target genes were also discovered, including miR-125, miR-1306, and miR-138, etc. Results from Gene Ontology (GO) and KEGG pathway analysis further confirmed there are a majority immune response targets of the miRNAs involved in the EP treatment process. Our study deepened understanding roles of miRNAs in fish immune system and provides new ideas for the study of immune mechanism of EP.

Evaluation of immunostimulatory attributes of Asparagus racemosus and Withania somnifera supplemented diets in fish, Channa punctatus (Bloch, 1793)

With the progression of aquaculture industry, there has been a spurt in dietary supplementation with economically viable medicinal herbs having enough immunostimulatory potential. This also aids in avoidance of environmentally undesirable therapeutics that are almost inevitable to safeguard fish against an array of diseases in aquaculture practices. The study aims to determine the optimal dose of herbs that can stimulate substantial immune response in fish for reclamation of aquaculture. Immunostimulatory potential of the two medicinal herbs- Asparagus racemosus (Shatavari), Withania somnifera (Ashwagandha), individually, and in combination, with a basal diet was screened up to 60 days in Channa punctatus. 300 laboratory acclimatized healthy fish (14 ± 1 g; 11 ± 1 cm) were divided into ten groups- C, S1, S2, S3, A1, A2, A3, AS1, AS2, and AS3, based on the composition of dietary supplementation, in triplicates, with 10 specimens per group. The hematological index, total protein and lysozyme enzyme activity were performed after 30 and 60 days, while qRT-PCR analysis of lysozyme expression was done after 60 days of the feeding trial. The significant (P < 0.05) increments in hematological indices- (TEC, TLC, DLC, Hb, Hct, MCV, MCH and MCHC), total protein content and serum lysozyme activity, after 30 and 60 days; whereas upregulation of lysozyme transcript levels, both in liver and muscle tissues after 60 days of the feeding trial were recorded in groups- AS1, AS2, and AS3. The maximal increment in lysozyme expression was recorded in AS3, both in liver and muscle tissues, with 3.75 ± 0.13 and 3.21 ± 0.18-folds, respectively. However, increments were non-significant (P > 0.05) for MCV in AS2 and AS3 after 30 days; and for MCHC in AS1 for both the durations; whereas in AS2 and AS3, after 60 days of the feeding trial. A positive correlation (P < 0.05) among lysozyme expression, MCH, lymphocytes, neutrophils, total protein content, and serum lysozyme activity in AS3, after 60 days, conclusively, evinces that a 3% dietary supplementation with both A. racemosus and W. somnifera enhances immunity and health profile of the fish, C. punctatus. The study, thus finds ample scope in augmentation of aquaculture production and also paves the way for more researches for biological screenings of potential immunostimulatory medicinal herbs that can be appropriately incorporated in the fish diet.

Synbiotic Effects of Saccharomycescerevisiae, Mannan Oligosaccharides, and β-Glucan on Innate Immunity, Antioxidant Status, and Disease Resistance of Nile Tilapia, Oreochromis niloticus

Synbiotic (SYN) additives were assessed as an antibiotic alternative on the effects on the nonspecific immune response and disease resistance of O. niloticus to P. aeruginosa. Healthy fish (n = 120, average initial weight 18 ± 2 g) were allotted randomly into four experimental groups (3 replicates for each); 1) a control group with no additives (CON), 2) basal diet complemented with 0.1 g kg^-1 diets of norfloxacin, NFLX, 3) basal diet fortified with 1 mL kg^-1 diet of SYN, and 4) basal diet complemented with a mixture of NFLX and SYN, which was carried out for eight weeks. Results showed a significant increase (p < 0.01) in the serum immune parameters (total protein, globulin and albumin, nitric oxide (NO), and lysozyme activity) in the SYN group and the NFLX+SYN group compared with the CON and NFLX groups. The serum glucose, cholesterol, and triglycerides were higher in NFLX and NFLX+SYN groups than the CON and SYN groups. The catalase (CAT), superoxide dismutase, glutathione peroxidase (GPX) activities were significantly augmented in the NFLX+SYN group, followed by the SYN group compared with CON and NFLX groups. The cumulative mortality rate (CMR) of O. niloticus following the P. aeruginosa challenge was decreased in the SYN group compared to other groups. The results emphasize that synbiotic could be used as a norfloxacin alternative to enhance the related immunological parameters, including antioxidant activity and disease resistance against P. aeruginosa infection of O. niloticus.

Dietary flavonoid intake and risk of periodontitis

BACKGROUND

The anti-inflammatory effect associated with flavonoid-containing foods and beverages could potentially impact the risk of periodontal disease. We prospectively investigate the associations between habitual flavonoid intake and incidence of periodontitis.

METHODS

The study population was 34,940 men from the Health Professionals Follow-Up Study, who were healthy and free of periodontal disease at baseline (1986). Participants in the study provided medical and dental history through mailed questionnaires biennially, and provided dietary data through semi-quantitative food frequency questionnaires every 4 years. We examined the associations between total flavonoids and six flavonoid subclasses (flavonoid polymers, anthocyanins, flavan-3-ols, flavanones, flavones, and flavonols) and incidence of periodontitis using Cox proportional hazard models. We adjusted for age, smoking, body mass index, physical activity, alcohol consumption, Alternative Healthy Eating Index, and diabetes.

RESULTS

There was no association between total flavonoids and the risk of periodontitis. The hazard ratio comparing the highest quintile of total flavonoid to the lowest quintile was 0.97 (95% confidence interval: 0.87 to 1.08, P-value for trend = 0.61). Similar comparisons for flavonoids subclasses also did not show significant associations.

CONCLUSION

No association was detected between habitual flavonoid intake and risk of periodontitis in the study population.

The Effect of Diet Supplemented with Dandelion’s (Taraxacum Officinale) Extract on the Productive and Blood Parameters of Common Carp (Cyprinus Carpio L.), Cultivated in the Recirculation System

The aim of the current study was to test the effect of a diet supplemented with dandelion’s (Taraxacum officinale) extract on the productive traits and blood parameters in common carp (Cyprinus carpio L.) cultivated in an recirculation aquaculture system. The carps were cultivated at a stocking density of 7.2 kg/m3 in recirculation aquaculture system. The fish were split into the following two experimental groups: DF (the fish were fed with feed supplemented with dandelion’s extract) and CF (the fish were fed with feed without supplementation). Common carp fed with a diet added with dandelion’s extract at a quantity of 0.8% from daily feed ratio, did not affect the hydrochemical parameters (pH, dissolved oxygen, and electrical conductivity). The carps fed with feed supplemented with dandelion’s extract did not show better productive traits compared with these found for carp from the control variant. The carp from experimental groups had a higher survival rate, final weight, average individual weight gain and specific growth rate (SGR), respectively with 13.2%, 3.94%, 31.5% and 31.3%, compared with the average values of these parameters measured in individuals fed with the control feed, but the differences were not statistically significant (P≥0.05). Supplementation of feed with dandelion’s extract significantly decreased the plasma cholesterol (4.76%) and triglyceride (61.2%) content, promoting hypolipidemic status in fish (P≤0.05).

Echinacea biotechnology: advances, commercialization and future considerations

CONTEXT

Plants of the genus Echinacea (Asteraceae) are among the most popular herbal supplements on the market today. Recent studies indicate there are potential new applications and emerging markets for this natural health product (NHP).

OBJECTIVE

This review aims to synthesize recent developments in Echinacea biotechnology and to identify promising applications for these advances in the industry.

METHODS

A comprehensive survey of peer-reviewed publications was carried out, focusing on Echinacea biotechnology and impacts on phytochemistry. This article primarily covers research findings since 2007 and builds on earlier reviews on the biotechnology of Echinacea.

RESULTS

Bioreactors, genetic engineering and controlled biotic or abiotic elicitation have the potential to significantly improve the yield, consistency and overall quality of Echinacea products. Using these technologies, a variety of new applications for Echinacea can be realized, such as the use of seed oil and antimicrobial and immune boosting feed additives for livestock.

CONCLUSIONS

New applications can take advantage of the well-established popularity of Echinacea as a NHP. Echinacea presents a myriad of potential health benefits, including anti-inflammatory, anxiolytic and antibiotic activities that have yet to be fully translated into new applications. The distinct chemistry and bioactivity of different Echinacea species and organs, moreover, can lead to interesting and diverse commercial opportunities.

The effects of the dietary supplementation of Echinacea purpurea extract and/or vitamin C on the intestinal histomorphology, phagocytic activity, and gene expression of the Nile tilapia

In this study, the influence of the dietary incorporation of Echinacea purpurea (EP) extract and/or vitamin C on the intestinal histomorphology and some immunological indices were tested in the Nile tilapia (Oreochromis niloticus Linn.). O. niloticus were randomly divided into four groups. The control group G₁ was fed on a basal diet, while the G₂ and G₃ were fed on basal diets, supplemented with EP extract and vitamin C at the doses of 500 mg kg^-1 and 400 mg kg^-1, respectively. Meanwhile, G₄ was fed on a basal diet, supplemented with a mixture of EP extract and vitamin C. After 28 days of feeding, the intestinal tissues were collected for histological observation and immune status, was based on an assay for measuring the phagocytic activity. Furthermore, the expression of the transforming growth factor-beta 1 (TGF-β1), interleukin-1beta (IL-1β), and tumor necrosis factor alpha (TNF-α) genes was evaluated in intestine and head kidney. The results revealed that the G₄ successfully surpassed the other groups in terms of the heights of intestinal villi, the number of goblet cells and intraepithelial lymphocytes (IELs), and the phagocytic activity, followed by the G₃ and G₂. The expression of the IL-1β and TNF-α genes were up regulated only in G₄ but in the G₃ only the expression of the IL-1β gene was up regulated. Hence, EP extract along with vitamin C could be used as a feed additive in order to improve the structure of the intestinal mucosal epithelium and immune response in tilapia.

Growth performance and haematological and immunological indices of rainbow trout (Oncorhynchus mykiss) fingerlings supplemented with dietary Ferulago angulata (Schlecht) Boiss

In this study, the effects of Ferulago angulata extract on the growth, haematological, and immunological indices of rainbow trout (Oncorhynchus mykiss) fingerlings were evaluated. Basal diet was supplemented with 0 (control), 0.5, 1, and 2 g·kg-1 F. angulata and was randomly allocated to experimental fish of an initial average weight of 7.45 ± 0.02 g. After 8 weeks of experiment, the fish supplemented with F. angulata extract showed increased but non-significant (P > 0.05) growth performance. No significant differences were found between trial control groups in haematological indices such as red blood cell count, haematocrit, and haemoglobin, but there was a significant increase in white blood cells, lymphocytes, neutrophils and monocytes in the F. angulata extract groups (P < 0.05). Also, there were significant differences between the fish supplemented with dietary F. angulata extract and the control group regarding immunological indices, including immunoglobulin M, lysozyme, and classical and alternative complement pathway (P < 0.05). These findings suggest that the administration of F. angulata extract has a positive effect on the immunological indices and the immune system activity in rainbow trout fingerling.

Camellia sinensis supplemented diet enhances the innate non-specific responses, haematological parameters and growth performance in Mugil cephalus against Photobacterium damselae

This study evaluated the effect of dietary supplementation of Camellia sinensis leaf-extract on non-specific immune responses and disease resistance of Mugil cephalus fingerling against P. damselae. Fish were fed with 0 (unsupplemented), 50, 100 and 200 mg/kg of green tea extract (GTE) supplemented diets. Results indicated that GTE decreased mortality in M. cephalus in a dose-dependent manner after challenge with P. damselae. Haematological parameters containing RBC, Hct, Hb and WBC and growth performance (weight gain) showed remarkable changes in comparison with control group. In addition, the phagocytic (PA) and respiratory burst activity (RBA) significantly increased in M. cephalus, fed 100 and 50, 100 and 200 mg/kg GTE, respectively. Lysozyme statistically increased in GTE supplemented fish. Overall, our results indicated that incorporation of C. sinensis supplemented diet at 100 and 200 mg/kg doses significantly enhanced the immune responses in M. cephalus and that the mortality percentage could be remarkably reduced after challenging the fish against P. damselae.

Impact of date palm fruits extracts and probiotic enriched diet on antioxidant status, innate immune response and immune-related gene expression of European seabass (Dicentrarchus labrax)

The application of additives in the diet as plants or extracts of plants as natural and innocuous compounds has potential in aquaculture as an alternative to antibiotics and immunoprophylactics. The aim of the current study was to evaluate the potential effects of dietary supplementation of date palm fruit extracts alone or in combination with Pdp11 probiotic on serum antioxidant status, on the humoral and cellular innate immune status, as well as, on the expression levels of some immune-related genes in head-kidney and gut of European sea bass (Dicentrarchus labrax) after 2 and 4 weeks of administration. This study showed for the first time in European sea bass an immunostimulation in several of the parameters evaluated in fish fed with date palm fruits extracts enriched diet or fed with this substance in combination with Pdp 11 probiotic, mainly after 4 weeks of treatment. In the same way, dietary supplementation of mixture diet has positive effects on the expression levels of immune-related genes, chiefly in head-kidney of Dicentrarchus labrax. Therefore, the combination of both could be considered of great interest as potential additives for farmed fish.

The effects of garlic-supplemented diets on skin mucosal immune responses, stress resistance and growth performance of the Caspian roach (Rutilus rutilus) fry

This study was conducted to evaluate the effects of garlic supplementation on some skin mucus immune parameters, mucus antimicrobial activity and growth performance of the Caspian roach (Rutilus rutilus caspicus) fry. Fish (1 ± 0.07 g) were divided into four groups fed diets containing 0 (control), 5, 10 and 15 g kg(-1) garlic for 8 weeks. The results showed that there was a significant increase in weight gain and specific growth rate in those fish fed garlic diets compared with the control (P < 0.05). Condition factor was not significantly affected by garlic dosage. At the end of trial, the epidermal mucus protein level, alkaline phosphatase and antimicrobial activity against 2 g-negative bacteria (Escherichia coli and Serratia marcescens) and gram-positive bacteria (Streptococcus faecium and Micrococcus luteus) were measured. Skin mucus alkaline phosphatase, protein levels and antimicrobial activity were increased following garlic administration, and the bacterial growth inhibition zones were significantly elevated in garlic-fed fish (P < 0.05). In salinity stress experiment, no differences were observed for survival rate among the experimental diets. No mortality was recorded during the feeding trial. These results indicated that dietary garlic beneficially affects the skin mucus immune parameters and growth performance of the Caspian roach fry.

Aloe vera bathing improved physical and humoral protection in breeding stock after induced spawning in matrinxã (Brycon amazonicus)

In this study, we show that induced spawning causes stress, an intense loss of epithelia and immunosuppression, decreasing physical and humoral protection in fish, effects that were prevented or improved in fish bathed with Aloe vera. A. vera has several medicinal properties, including wound healing and immunostimulatory effects, which we observed in this study. Fish bathed with A. vera had a higher number of epidermal goblet cells and, in general, an improved wound healing rate compared with the control after induced spawning. These effects might be related to (1) the stimulation of leukocyte activity, represented here by the increased leukocyte respiratory activity triggered by A. vera (leukocytes are recognized as playing an important role in wound repair); (2) the antimicrobial properties of A. vera, which decrease wound infection and accelerate the healing process; and (3) several mechanisms that explain the healing effect of A. vera (increased collagen synthesis, rate of epithelialization, and anti-inflammatory and moisturizing effects). Our results also suggest that caution is necessary during the induced spawning process, especially during stripping, and A. vera bathing is recommended after intensive aquaculture operations.

Effect of dietary supplementation with Echinacea purpurea on vaccine efficacy against infection with Flavobacterium columnare in zebrafish (Danio rerio)

The effect of dietary Echinacea purpurea (EP) on the response of zebrafish (Danio rerio) to a Flavobacterium columnare vaccine was investigated. Two hundred D. rerio with an average weight of 290 ± 40 g were selected and fed different levels of E. purpurea (5 g kg-1 diet - group 1, 10 g kg-1 diet - group 2, 20 g kg-1 diet - group 3, 30 g kg-1 diet - group 4, and 0 g kg-1 diet - group 5). Experimental feeding was begun 3 weeks prior to bath immunization and continued until the end of the experiment. Twenty-eight days after immunization the fish were challenged by bath immersion with F. columnare at a concentration of 1x106 CFU/ml. The relative percent survival of the experimental groups (1, 2, 3, 4 and 5) was 5.0, 6.0, 30.0, 36.0 and 5.0, respectively. In conclusion, diet supplementation with E. purpurea may effectively enhance the response of zebrafish to a F. columnare vaccine.