Growth performance, mucosal immunity and disease resistance in goldfish (Carassius auratus) orally administered with Escherichia coli Strain Nissle 1917.

The current research aimed to shed light on the efficacy of Escherichia coli strain Nissle 1917 (EcN) on goldfish (……) growth, gut immunity, morphology, bacterial nutritional enzyme activity and resistance to Aeromonas hydrophila infection. Fish fed with EcN at 106, 107 and 108 CFU/g feed for 80 days showed an enhancement in growth better than control fish. The gut innate immunity in terms of lysozyme activity, immunoglobulin and total protein levels was increased in the treatment fish with the best result being observed in fish fed EcN at 108 CFU/ g. In addition, an increase was noted in the upregulation of immune-relevant genes, namely lysozyme, interleukin-1ß, inducible nitric oxide synthase and tumor necrosis factor α of fish intestine. A marked surge in the number of proteolytic and heterotrophic bacteria was noted in the gut of fish nourished with the probiotic. Histological studies exhibited an improvement in the intestinal absorption surface area, intraepithelial lymphocyte count and goblet cell density. Significantly higher survival rate was obtained in fish fed EcN at 108 CFU/g compared with the fish fed with the basal diet. These data exhibited the beneficial effect of EcN on goldfish growth, digestive enzymes, intestine heterotrophic bacteria and resistance against Aeromonas hydrophila challenge. This study confirmed the favorable outcomes resulting from the administration of EcN at108 CFU/g.

Immunomulation effect of alginic acid and chitooligosaccharides in silver carp (Hypophthalmichthys molitrix).

Individual and combined efficacy of chitooligosaccharides (COS) and alginic acid (AA) at 1 g, 2 g, and 3 g per kg diet was assessed on growth and disease resistance in silver carp (Hypophthalmichthys molitrix) against Edwardsiella ictaluri. Growth parameters including specific growth rate (SGR), weight gain (WG), and feed conversion rate (FCR) were significant in fish fed 2 g and 3 g kg-1 of COS or AA, and fish fed combined COS + AA at 1, 2 and 3 kg-1 diet. In all groups, the survival rate (SR) was recorded 100%, except in group fed 2 g kg-1 AA diet. All the hematological and biochemical profiles significantly increased in groups fed 2 g and 3 g kg-1 of COS, AA, and COS + AA diets. Lipase and amylase enzyme activities and superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GPx) antioxidant enzyme activities were significantly increased in fish fed 2 g and 3 g kg-1 of COS, AA, and COS + AA diet. Respiratory burst (RB), lysozyme (Lyz), reactive oxygen species (ROS) activities, and immunoglobuline (Ig) level were enhanced significantly in fish fed 2 g kg-1 of COS or COS + AA and all 3 g kg-1 diets, whereas nitric acid (NO) production and serum AP activity were improved in 2 g kg-1 COS + AA and 3 g kg-1 COS or COS + AA diets. Pro-inflammatory cytokine such as IL-8 mRNA transcriptions was significant in 2 g kg-1 COS + AA diet and all 3 g kg-1 diet. The IL-10 anti-inflammatory cytokine mRNA transcriptions were significant in 3 g kg-1 COS or COS + AA diets. This study was confirmed that H. molitrix fed with 3 g kg-1 COS or COS + AA diets were better activity when compared to other diet.

Study on antioxidant potential, immunological response, and inflammatory cytokines induction of glycyrrhizic acid (GA) in silver carp against vibriosis.

Effect of dietary with 100, 200, and 300 mg kg-1 glycyrrhizic acid (GA) on growth enhancer, blood physiology, digestive-antioxidant enzyme ability, innate-adaptive defense, and inflammatory cytokines induction was studied in silver carp, Hypophthalmichthys molitrix against vibriosis caused by Vibrio alginolyticus. Significant weight gain (WG), specific growth rate (SGR), and 100% survival rate (SR) was attained non-infected health (NiH) fish fed in control or all GA diets on 30, 45, and 60 days. Both NiH and V. alginolyticus challenged (VaC) fish treated with 200 mg GA diet significantly (P < 0.05) exhibited an enhancement in leucocytes value on 30, 45, and 60 days. Albumin (AB) or total proteins (TP) levels were significantly (P < 0.05) better in both groups fed 200 GA on 45 and 60 days. Malondialdehyde (MDA) and superoxide dismutase (SOD) activities were also substantial (P < 0.05) in both groups fed 200 mg GA on days 30, 45, and 60; whereas glutathione peroxidase (GPx) and catalase (CAT) activities were significantly (P < 0.05) better in both groups received 200 mg GA on days 45 and 60. Phagocytic (PC) and lysozyme (Lyz) activities significantly enhanced in both groups fed 200 or 300 mg GA on 45 and 60 days. Respiratory burst (RB), reactive oxygen species (ROS) and immunoglobulin (Ig) production significantly (P < 0.05) increased in both groups administered 200 or 300 mg GA. Growth hormone (GH) mRNA was up regulated in 200 mg GA trial on 45 days and in 200 or 300 mg GA treatments on 60 days. The IL-8 cytokine mRNA expression was up-regulated in both groups 200 and 300 mg GA on days 45 and 60, whereas TNF-α mRNA expression was increased in 200 mg GA. In addition, IL-10 cytokine mRNA expression was up regulated in 200 mg GA on 45 days whereas it was increased in both 200 mg and 300 mg GA trial on 60 days. The present study revealed that feeding fish 200 mg GA per kg diet demonstrated a better growth, digestive-antioxidant activity, innate-adaptive defense, and inflammatory cytokines induction than lower or higher dosage of GA in H. molitrix against V. alginolyticus.

Influence of bamboo vinegar powder (BVP) enriched diet on antioxidant status, immunity level, and pro-anti-inflammatory cytokines modulation in Asian sea bass, Lates calcarifer (Bloch 1790) against Vibrio anguillarum.

Effect of bamboo vinegar powder (BVP) on growth, immunity, disease resistance, and immune-related gene expressions in juvenile Asian sea bass (barramundi), Lates calcarifer against Vibrio anguillarum was investigated. V. anguillarum infected fish fed by 2g BVP kg-1 diet exhibited significant growth, albumin (AB), serum total protein (TP), and globulin (GB) levels. Similarly, enhanced lysozyme (LZM), phagocytic (PC), anti-protease (AP), respiratory burst (RB), bactericidal (BC) activities and total immunoglobulin (Ig) levels were observed in fish fed 2g BVP kg-1. In addition, use of 2g BVP kg-1 in diet modulated several immune related gene expressions against Vibrio disease. This study exhibited a positive effect of dietary 2g BVP kg-1 diet on hemato-biochemical and immunological responses, which enhance the immunocompetence and health status of L. calcarifer against V. anguillarum infection.

Cyprinid herpesvirus 3 (CyHV-3) transmission and outbreaks in Iran: Detection and characterization in farmed common carp.

This study shows the presence of Cyprinid Herpesvirus-3 (CyHV-3) in common carp (Cyprinus carpio) from Iranian carp farms with cumulative mortality up to 80% during 2015-2016. Pathological signs of disease such as gill necrosis, sunken eyes, and increased slime secretion on the skin and fins were observed in affected fish. The extensive fusion of secondary lamellae with necrotic cells, margination of chromatin, and formation of intranuclear inclusion bodies in gill tissues were also observed by histopathological examination. Most tubular epithelial cells and some hematopoietic cells showed intranuclear inclusion bodies in the kidney. The Iranian CyHV-3 isolates showed identity with Asian strains, and displayed the I++ II+ allele of the Asian lineage, as revealed by sequence analysis of the TK gene, Marker I, and Marker II. The detected isolates were also similar to those detected from koi in the same region of Iran, suggesting the probable transmission of CyHV-3 from ornamental to farmed cyprinids. This represents the first report of CyHV-3 from Iranian farmed common carp to the best of our knowledge.

Effects of dietary chitosan and nano-chitosan loaded clinoptilolite on growth and immune responses of rainbow trout (Oncorhynchus mykiss).

In this study, rainbow trout Oncorhynchus mykiss weighing 27.75 ± 0.34 g were orally subjected to eight experimental diets each in three replicates containing varying amounts of chitosan and nano-chitosan (0.05, 0.5 and 5 g kg-1) loaded in clinoptilolite (14.28 g kg-1) for 70 days; and the growth and immune responses were evaluated. Results showed that growth parameters in fish fed diets chit + clin2, chit + clin3, nchit + clin1, nchit + clin2 and nchit + clin3 were significantly higher than in fish fed the control diet. All feeds, except chit + clin3, and nchit + clin3, significantly increased the total protein level. Feeds containing chit + clin2, nchit + clin1, and nchit + clin2 significantly elevated serum lysozyme activity compared with the control group. All treatments, except chit + clin3, and nchit + clin3 exhibited higher serum immunoglobulin (Ig) level than control one. In contrast, diet nchit + clin1 significantly unregulated the expression of Ig M gene in fish head-kidney compared to other groups. Additionally, all feeds, except clinoptilolite, and nchit + clin3, significantly improved the serum complement activity. Diets chit + clin2, nchit + clin1, and nchit + clin2 also significantly elevated antibacterial activity against Yersinia ruckeri compared with the control diet. Expression of inducible nitric oxide synthase (iNOS) gene in fish fed diets clinoptilolite, chit + clin1, chit + clin3, nchit + clin1, nchit + clin2, and nchit + clin3 was significantly higher than the control diet. All diets, except clinoptilolite, increased IL-1ß gene expression compared to the control group. Present results suggest that diets supplemented with nchit + clin, especially at 0.05 g kg-1 nano-chitosan inclusion, could improve growth performance and immune parameters of rainbow trout.

Oral immunization of trout fry with recombinant Lactococcus lactis NZ3900 expressing G gene of viral hemorrhagic septicaemia virus (VHSV).

This study has investigated the ability of Lactococcus lactic (NZ3900) carried G gene of viral haemorrhagic septicaemia virus (VHSV) under nisin-controlled gene expression (NICE) system in rainbow trout (O.Mykiss). Two groups of trout fry (7 ± 0.65 g) were immunized with 1 × 1010 cfu/g and 1 × 108 cfu/g recombinant L. lactis NZ3900, two groups of fish were fed 1 × 1010 cfu/g and 1 × 108 cfu/g L. lactis vector free, and one group was fed by the basal diet as a control. Oral immunization was done on days 1-7 and boosting was performed on days 15-21. The relative expression of IFN-1 and MX-1 genes significantly increased in head kidney of vaccinated fish depend on vaccine dosage compared to the control group. Fish in vaccinated group also showed elevated VHSV-specific antibody levels compared to the control groups. Relative percent survival (RPS), under virulent isolate VHSV challenge were estimated 62%, 78% for 108 cfu/g 1010 cfu/g feed vaccinated groups 21 days post-vaccination, while groups fed similar doses of L. lactis vector free illustrated 22% and 27% RPSs, respectively. The significant reduction of viral loads (transcript levels of N gene) were detected in the immunized groups. Increased weight gain and decreased feed consumption in vaccinated group attributed to the probiotic effect were also observed. In conclusion, our results demonstrate the ability of recombinant L. lactis as oral vaccine against VHS in rainbow trout, which can be considered as effective method against different fish pathogens.

Dietary sodium butyrate (Butirex® C4) supplementation modulates intestinal transcriptomic responses and augments disease resistance of rainbow trout (Oncorhynchus mykiss).

Intestine in fish is a complex multifunctional organ, not only plays roles in digestion and absorption of nutrient, but also has critical role in immunity. The present study evaluated the effects of different levels of dietary sodium butyrate [Butirex® C4 (Butirex)] on intestinal immune-,antioxidant-and tight junction-related gene expression injuvenile rainbow trout(Oncorhynchusmykiss). 240 healthy rainbow trout were dispensed in 12 fiberglass tanks appointed to four treatments [0 (control), 1.5 (B1.5), 2.5 (B2.5) and 5 (B5)g Butirex per kg diet]. After a 45-day feeding trial, the fish fed with the Butirex-supplemented diets showed higher intestinal lysozyme (LYZ), complement(ACH50) and bactericidal activities; the elevations in ACH50 and bactericidal activities depended on Butirex levels (P < 0.05). The Butirex-supplemented groups, particularly the B2.5 group, had significantly higher LYZ gene expression compared to the control group (P < 0.05). Butirex at 2.5 and 5 g/kg levels led to significantly higher IL-1ß gene expression. B2.5 and B5 had significantly lower and higher TNF-α gene expression compared to the control group (P < 0.05). The B2.5 group had significantly higher TGF-B, and significantly lower IL-8 compared to the control group (P < 0.05). The B1.5 and B2.5 group had significantly higher IL-10 gene expression compared to the control group (P < 0.05). The B2.5 and B5 groups had significantly higher SOD gene expression compared to the other groups; the highest expression was related to the B2.5 group (P < 0.05). Dietary Butirex supplementation significantly up-regulated CAT and GPx genes expression compared to the control group; the highest expression as related to the B2.5 and B5 groups (P < 0.05). The B2.5 group had significantly lower CLD12 gene expression compared to the control group (P < 0.05). The B2.5 and B5 groups had significantly higher CLD3, OCLD and ZO-1 gene expression compared to the control. The highest CLD3, ZO-1 gene expressions was related to the B2.5, and B5 groups respectively (P < 0.05). After challenge with Streptococcus iniae, B2.5 and B5 had significantly higher survival compared to the control group (55.6 ±â€¯7.70 and 68.9 ±â€¯10.2 vs. 33.3 ±â€¯6.67). In conclusion, Butirex is efficient immune stimulant and health booster in rainbow trout, which augments the fish resistance to disease. Modulation of immune components, cytokines, antioxidant system and intestinal integrity might involve in improving disease resistance in Butirex-treated fish. Although most of the examined genes were modulated by 2.5 g/kg Butirex under normal conditions, 5 g/kg level is recommended under pathogenic state to mitigate mortality.

Effects of elephant's foot (Elephantopus scaber) extract on growth performance, immune response, and disease resistance of nile tilapia (Oreochromis niloticus) fingerlings.

Medicinal plant has been applied as an alternative strategy for antibiotics and chemotherapeutics for controlling the outbreak of diseases in tilapia farming. In this study, five doses of Elephantopus scaber extract (ESE) were added to the basal diet at 0, 2.5, 5, 10, and 20 g kg-1 feed of Nile tilapia fingerlings (13.92 ±â€¯0.06 g initial weight) in triplicate. After 4- and 8- weeks post-feeding, fish were sampled to determine the effects of the ESE supplemented on fish's growth performance, humoral, and skin mucus immune response. After 8 weeks post-feeding, a challenge test against Streptococcus agalactiae was carried out using 10 fish from each tank. Fish fed ESE showed significantly increased serum lysozyme (SL), serum peroxidase (SP), alternative complement (ACH50), phagocytosis (PI), and respiratory burst (RB) compared to the control group (P < 0.05). The skin mucus lysozyme (SMLA) and skin peroxidase (SMPA) were stimulated in fish fed ESE diets. Dietary inclusion of ESE significantly (P < 0.05) promoted final body weight (FW), weight gain (WG), and specific growth rate (SGR); while a reduction in feed conversion ratio (FCR) was observed in fish fed 5 g kg-1 ESE, after 8 weeks post-feeding. The challenge study indicated that the relative percent survival (RSP) was 38.10%, 76.19%, 66.67%, and 47.62% in Diet 2, Diet 3, Diet 4, and Diet 5, respectively. Among the supplemented groups, dietary of 5 g kg-1 ESE showed significantly higher RPS and the highest resistance to S. agalactiae in comparison with other groups. In conclusion, supplementation of ESE (5 g kg-1) enhanced the humoral and mucosal immunity, promoted growth performance, and improved disease resistance of Nile tilapia against Streptococcus agalactiae.

Immuno-physiological and antioxidant responses of Siberian sturgeon (Acipenser baerii) fed with different levels of olive pomace.

Nowadays, use of the natural plant derivatives as an immunostimulant in aquaculture is becoming more useful than antibiotics which are destructive to target animals, consumers, and the environment. The present study aimed to evaluate the efficacy of dietary substitution of wheat flour at 2, 5, 7.5, and 10% of olive pomace (OP2, OP5, OP7.5, and OP10) in some immune-physiological and antioxidant variables of yearling Siberian sturgeon (Acipenser baerii) weighing 165 ± 6.8 g at 19.1 ± 1.52 °C for 56 days. Fifteen fish per tank were randomly accommodated in triplicates per treatment and the control group was also included. No significant difference was seen in hematological indices including red blood cells (RBS) and immunocompetent cell population sizes among the treated groups (P > 0.05). Also, malondialdehyde (MDA) activity and superoxide dismutase (SOD) in serum remained unaffected in different treatments (P > 0.05). Total protein (TP), high-density lipoprotein (HDL), catalase (CT), and lysozyme were affected by dietary OP levels (P < 0.05), and the highest value was observed at the OP5 diet, but no influence was seen in serum IgM by OP. These data show that application of olive pomace as a partial substitute of wheat flour in the diet of Siberian sturgeon is feasible with stimulatory and antioxidant functions.

Developing an applied algorithm for multi-trip vehicle routing problem with time windows in urban waste collection: A case study.

This paper studies a multi-trip vehicle routing problem with time windows specifically related to urban waste collection. Urban waste collection is one of the municipal activities with large costs and has many practical difficulties. In other words, waste collection and disposal is a costly task due to high operating expenses (fuel, maintenance, recycling, manpower, etc.) and small improvements in this field can result in tremendous savings on municipal expenditure. In the raised problem, the goal is to minimize total cost including traversing cost, vehicle employment cost, and exit penalty from permissible time windows. In this problem, the waste is deposited at the points indicating the demand nodes, in which each demand shows the volume of generated waste. Considering multiple trips for vehicles and time windows are the most critical features of the problem, so that the priorities of serving some specific places such as hospitals can be observed. Since vehicle routing problems (VRP) belongs to NP-hard problems, an efficient simulated annealing (SA) is proposed to solve the problem. The computational results show that our proposed algorithm has a great performance in a short computational time in comparison with the CPLEX solver. Finally, in order to demonstrate the applicability of the model, a case study is analyzed in Iran, and the optimal policies are presented.

Adjuvant efficacy of G2 (buffalo spleen extraction) against Yersinia septicemia in rainbow trout (Onchorhynchus mykiss).

Adjuvant effect of G2 (extraction of buffalo spleen) was assessed in intraperitoneally immunized rainbow trout (100-150 g) with killed- Y. ruckeri bacterin biotype I [0.1 mL (1 × 107 cells/fish) of vaccine diluted with the adjuvant in a ratio of 1:1 (V/V)] at 12.4 ±â€¯1.3 °C for 10 weeks. Leukocyte and lymphocyte counts, anti-Y. ruckeri antibody titer and relative percent survival (RPS) in fish vaccinated with vaccine containing the adjuvant were significantly higher than the immunized fish with Y. ruckeri antigen alone throughout the experiment (P < 0.05), but neutrophils count and lysozyme activity were mostly significantly higher in the latter group (P < 0.05). No difference was seen in the complement activity between vaccinated fish containing the adjuvant and vaccine alone (P > 0.05). The results of this work for the first time demonstrated that inclusion of G2 as an adjuvant in Y. urckeri vaccine can improve the efficacy of the vaccine against Yersinia septicemia in rainbow trout.

Some immunological responses of common carp (Cyprinus carpio) fingerling to acute extremely low-frequency electromagnetic fields (50 Hz).

Increasing of anthropogenic electromagnetic fields in aquatic environments has been recently become the core of attention. In this study, the effect of extremely low-frequency electromagnetic fields (50 Hz) on immune status and metabolic markers of common carp fingerling was assessed. The fish were exposed to extremely low-frequency electromagnetic fields at four intensities of 0.1, 0.5, 1, and 2 mT only once for 2 h; then, they were reared for 60 days. Results showed that the levels of aspartate aminotransferase (AST) and alanine transaminase (ALT) and alkaline phosphatase (ALP) were increased with an increase in the electromagnetic field intensity on 15 and 60 days post exposure. A significant increase was obtained in these enzyme levels in all the tested intensities compared to the control one (p < 0.05), with a maximum value measured in 2-mT trail. Conversely, with an increasing in the electromagnetic intensity, the levels of C3, C4, and lysozyme were reduced in all the treated groups in comparison with the control group (p < 0.05). The results suggested a significant impact of electromagnetic on fish immunophysiological functions. Therefore, it is required to have serious attention in aquatic ecosystems.

Effects of dietary nanoliposome-coated astaxanthin on haematological parameters, immune responses and the antioxidant status of rainbow trout (Oncorhynchus mykiss).

BACKGROUND: Astaxanthin is the most prevalent carotenoid in the marine environment and is widely used as an additive in formulated aquafeeds. OBJECTIVES: A 60-day feeding trial was conducted to consider the effect of dietary nanoliposome-coated astaxanthin (NA) on haematological parameters, serum antioxidant activities and immune responses of rainbow trout, Oncorhynchus mykiss. METHODS: A total of 450 healthy fish weighing 31.00 ± 2.09 g were randomly assigned in triplicate (30 fish per replicate) to 5 dietary treatments: 0 (control), 25.00, 50.00, 75.00, and 100.00 mg kg-1 NA. RESULTS: Fish fed the diet supplemented with 50.00 mg kg-1 NA exhibited the highest values of red blood cells, white blood cells, haemoglobin and haematocrit of 1.64 ± 0.01 × 106 mm-3, 5.54 ± 0.21 × 103 mm-3, 8.73 ± 0.24 g dL-1 and 46.67% ± 0.88%, respectively, which were significantly higher than those fed the basal diet (p < 0.05). The lowest and highest percentages of lymphocytes (67.67% ± 0.33%) and neutrophils (27.33% ± 1.20%) were also obtained in fish fed 50.00 mg kg-1 NA compared to those fed the basal diet (p < 0.05). Fish receiving diet supplemented with 50.00 mg kg-1 NA revealed the highest serum activity in superoxide dismutase, catalase, glutathione peroxidase, lysozyme and alternative complement and the lowest level of total cholesterol, cortisol, aspartate aminotransferase and alanine aminotransferase than fish receiving the basal diet (p < 0.05). Serum immunoglobulin (Ig) and ACH50 contents significantly increased with increasing dietary NA supplementation to the highest values of 43.17 ± 1.46 and 293.33 ± 2.03 U mL-1, respectively, in fish fed diet supplemented with 50 mg kg-1 NA (p < 0.05). CONCLUSIONS: Supplementation of NA in rainbow trout diet at 50 mg kg-1 exhibited a positive effect on haematological parameters, antioxidant capacity and immune responses. Administration of such dosage can enhance rainbow trout immune responses against unfavourable or stressful conditions, for example disease outbreaks, hypoxic condition, thermal stress and sudden osmotic fluctuations, which usually happen in an intensive culture system.

Assessment of rheological, qualitative and antioxidant characteristics of enriched peanut butter with date paste through shelf-life stability.

Over the years, concentrated efforts have been directed toward the improvement of desirable characteristics and attributes in peanut butter. This study examined the effect of rheological, antioxidant and qualitative characteristics of optimum peanut butter (including date paste and lecitin) during shelf-life. The results showed that the presence of date paste along with lecithin in optimum peanut butter improved the overall characteristics of peanut butter, including the physicochemical, microbial, mechanical, and sensory properties, compared to the control. Moreover, shelf-life had the most effect on reducing the emulsion stability, cohesiveness, antioxidant properties, and overall acceptance. In addition, the flow behavior of the emulsions was examined through the Herschel-Bulkley model using the parameters of determination coefficient, R2, flow behavior index, n, and consistency coefficient, K (Pa.sn). The presence of date paste in enriched peanut butter results in the creation of a colloidal structure among the peanut particles. This structure traps the oil, preventing it from leaving the peanut paste texture during shelf-life.

Efficacy of dietary live or heat-killed Bacillus subtilis in goldfish (Carassius auratus) infected with Ichthyophthirius multifiliis.

BACKGROUND: The beneficial effects of Bacillus subtilis on growth, immune response, and disease resistance against various diseases in different fish species have been proved. However, there are no data concerning this probiotic effect on skin mucosal immunity in fish infected with Ichthyophthirius multifiliis (Ich). Ich has a high mortality rate in both edible and ornamental fish and consequently is concerned with heavy economic losses. OBJECTIVES: Thus, we assessed the efficacy of live and heat-killed B. subtilis on skin immunity and histopathology in goldfish (Carassius auratus) infected with Ich. METHODS: Goldfish (144 fish, 2.38 g average weight) were stocked in nine glass tanks each in three replicates. Fish were fed 109 CFU g-1 live or heat-killed B. subtilis for 80 days. RESULTS: Probiotic administration in both viable and non-viable forms could enhance the growth performance in goldfish. Probiotic therapy also reduced the density of the parasite and histopathological level on skin and gill tissues of the treated fish. Real-time polymerase chain reaction analysis showed a higher expression of lysozyme and tumour necrosis factor-α in the treated groups compared to the control group. CONCLUSIONS: These data demonstrated the beneficial effect of B. subtilis as probiotic and paraprobiotic on growth performance and disease resistance to Ich infestation in goldfish.

The Effect of Gut Microbiota and Probiotics on Metabolism in Fish and Shrimp.

The present paper presents an overview of the effects of gut microbiota and probiotics on lipid-, carbohydrate-, protein- and amino acid metabolism in fish and shrimp. In probiotic fish studies, the zebrafish (Danio rerio) model is the most frequently used, and probiotic administration reveals the effect on glucose homeostasis, anti-lipidemic effects and increasing short-chain fatty acids, and increased expressions of genes related to carbohydrate metabolism and innate immunity, along with down-regulation of oxidative stress-related genes. Further, improved length of the intestinal villi and expression of nutrient transporters in fish owing to probiotics exposure have been documented. The present review will present an appraisal of the effect of intestinal microbiota and probiotic administration on the metabolism of nutrients and metabolites related to stress and immunity in diverse fish- and shrimp species. Furthermore, to give the reader satisfactory information on the topics discussed, some information from endothermic animals is also presented.

Brown Seaweed (Padina australis) Extract can Promote Performance, Innate Immune Responses, Digestive Enzyme Activities, Intestinal Gene Expression and Resistance against Aeromonas hydrophila in Common Carp (Cyprinus carpio).

Eight-week oral administration of Padina australis ethyl acetate extract at 100, 200, and 400 mg/kg diets was assessed on the growth performance, tight junction proteins, intestinal immunity, and disease resistance to Aeromonas hydrophila in common carp (Cyprinus carpio). A total of 300 healthy common carp weighing around 14.8 ± 0.03 g were randomly assigned into four equal groups within 12 glass aquariums, each in three replicates (25 fish/tank), for the feeding trial experiment. The first group served as the control group and was fed an un-supplemented diet, whilst the other three groups were offered diets containing graded amounts of Padina australis ethyl acetate extract at 100, 200, and 400 mg/kg, respectively. The growth indices, including final weight, length, weight gain rate, specific growth rate, and feed conversion ratio, were meaningfully improved in fish fed with the algae at 200 and 400 mg/kg compared to the control fish (p < 0.05). Similarly, digestive enzyme activities and serum immune parameters were significantly higher in all treatments, especially 200 and 400 mg/kg fed groups, compared to the control (p < 0.05). In parallel, significant upregulation of genes related to integrity and the immune system was shown in the intestine of these treatment groups compared to control fish (p < 0.05). When fish were challenged with A. hydrophila, the cumulative survival percentages were 53.3% (p = 0.215), 70.0 % (p = 0.009), and 76.7% (p = 0.002) in fish fed 100, 200, and 400 mg/kg diets, respectively, compared to 36.7% survival in control fish (p = 0.134). These data show that the eight-week dietary administration of P. australis extract to common carp can enhance growth performance, digestive enzyme activity, immune response, and disease resistance to A. hydrophila infection.

Effect of chia seed mucilage coating containing zinc oxide nanoparticles on shelf life of chicken fillet.

Chicken fillet is a suitable medium for growth and activity of different types of microorganisms. The pH and nutrients content of fillets are the most important factors in their microbial spoilage and degradation during cold storage at the retail level. In this regard, the uses of edible coatings containing antimicrobial and antioxidant compounds are effective approaches to maintain the quality of fillets. In this study the inhibitory effect of edible coating materials based on chia seed mucilage containing 0.00%, 0.25% and 0.50% zinc oxide nanoparticles (ZnO-NPs) on microbial growth and chemical spoilage as well as enhancing shelf life of chicken fillets during refrigerated storage for 20 days was investigated. The results of X-Ray diffraction confirmed the dispersion of ZnO-NPs on the chia seed mucilage matrix. Also, the number of total aerobic mesophilic and psychrophilic bacteria, coliforms and lactic acid bacteria, and the pH, total volatile nitrogen, peroxide and free fatty acids indexes in the control fillets were significantly increased compared to the fillets coated with chia seed mucilage during storage. While, in the samples coated with chia mucilage containing ZnO-NPs the number of the above-mentioned bacteria decreased in the first stage and then significantly increased during storing. Based on our findings, the shelf life of fillets could be increased at least 20 days by coating them with the chia seed mucilage containing ZnO-NPs.