ABSTRACT
Aloe vera is a traditional medicinal plant; however, its use in fish is fairly recent. We evaluated the effects of dietary A. vera on stress, innate immunity, and energy metabolism in pacu inoculated with Aeromonas hydrophila. For 7 days, 192 fish were fed with diets supplemented with 0% (control), 0.5%, 1.0%, and 2.0% of the plant extract and then inoculated with bacteria and sampled 3, 6, and 24 h later. All concentrations of A. vera reduced basal levels of cortisol, and 1.0% reduced cortisol levels more intensely 3 h after inoculation. A. vera increased the basal respiratory activity of leukocytes/RAL (0.5 and 1.0%), increased the serum levels of lysozyme (1.0 and 2.0%) 6 h after inoculation, and increased the activity of the complement system after 3 h. Spleen somatic index/SSI increased with 1.0 and 2.0% A. vera. A. vera also promoted metabolic effects. It increased basal levels of lipids in the liver and muscle, as well as hepatosomatic index (1.0%) and, 3 h after inoculation, prevented the reduction of serum triglyceride (1.0%) and reduced the mesenteric fat (1.0%). Bacterial inoculation increased RAL from 3 to 24 h and lysozyme levels at 24 h, increased serum cholesterol at 24 h, and decreased serum triglyceride from 3 to 24 h, regardless of A. vera. We concluded that A. vera offered for only 7 days had stress-reducing effects, stimulated innate immunity, protected triglyceride levels in blood, lipid depots in the liver and muscle, and directed the energy mobilization to visceral depots.
Subject(s)
Aeromonas hydrophila/pathogenicity , Aloe/chemistry , Characiformes/microbiology , Fish Diseases/drug therapy , Gram-Negative Bacterial Infections/veterinary , Plant Extracts/therapeutic use , Animals , Blood Glucose/analysis , Cholesterol/blood , Energy Metabolism/drug effects , Fish Diseases/diet therapy , Fish Diseases/microbiology , Glycogen/analysis , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/drug therapy , Hydrocortisone/blood , Immunity, Innate/drug effects , Leukocytes/drug effects , Leukocytes/physiology , Lipids/analysis , Liver/drug effects , Liver/metabolism , Muramidase/blood , Muscles/drug effects , Muscles/metabolism , Plant Extracts/administration & dosage , Plant Extracts/pharmacology , Random Allocation , Reactive Oxygen Species/metabolism , Stress, Physiological/drug effects , Triglycerides/bloodABSTRACT
European seabass (Dicentrarchus labrax) production is often hampered by bacterial infections such as photobacteriosis caused by Photobacterium damselae subsp. piscicida (Phdp). Since diet can impact fish immunity, this work investigated the effect of dietary supplementation of 5% Gracilaria sp. aqueous extract (GRA) on seabass antioxidant capacity and resistance against Phdp. After infection, mortality was delayed in fish fed GRA, which also revealed increased lysozyme activity levels, as well as decreased lipid peroxidation, suggesting higher antioxidant capacity than in fish fed a control diet. Dietary GRA induced a down-regulation of hepatic stress-responsive heat shock proteins (grp-78, grp-170, grp-94, grp-75), while bacterial infection caused a down-regulation in antioxidant genes (prdx4 and mn-sod). Diet and infection interaction down-regulated the transcription levels of genes associated with oxidative stress response (prdx5 and gpx4) in liver. In head-kidney, GRA led to an up-regulation of genes associated with inflammation (il34, ccr9, cd33) and a down-regulation of genes related to cytokine signalling (mif, il1b, defb, a2m, myd88). Additionally, bacterial infection up-regulated immunoglobulins production (IgMs) and down-regulated the transcription of the antimicrobial peptide leap2 in head kidney. Overall, we found that GRA supplementation modulated seabass resistance to Phdp infection.
Subject(s)
Animal Feed , Bass/physiology , Dietary Supplements , Fish Diseases/prevention & control , Gracilaria , Gram-Negative Bacterial Infections/veterinary , Photobacterium , Animals , Antimicrobial Cationic Peptides/biosynthesis , Antimicrobial Cationic Peptides/genetics , Aquaculture , Bass/blood , Bass/immunology , Blood Glucose/analysis , Cytokines/biosynthesis , Cytokines/genetics , Disease Resistance , Fish Diseases/diet therapy , Fish Diseases/immunology , Fish Diseases/metabolism , Gene Expression Regulation , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/immunology , Gram-Negative Bacterial Infections/prevention & control , Head Kidney/metabolism , Heat-Shock Proteins/biosynthesis , Heat-Shock Proteins/genetics , Immunoglobulin M/biosynthesis , Lipid Peroxidation , Liver/metabolism , Muramidase/blood , Triglycerides/bloodABSTRACT
BACKGROUND: The ubiquitous and opportunistic bacterial pathogen Aeromonas hydrophila has been associated with ulcerative dermatitis in fish, especially under stressful conditions. It can cause severe losses in fresh water aquaculture and is particularly prevalent in tropical and subtropical regions. Fresh leaves from maize and bananas have been used as feed supplement by fish farmers in Vietnam and it has been reported that they may have phyto-prophylactic benefits. In the present study, a feeding trial was conducted to investigate the benefits of providing maize and banana leaves as feed supplement: to determine if they were taken up and digested by grass carp (Ctenopharyngodon idella), if this uptake resulted in improved growth performance, and if leaf supplementation protected fish when challenged with A. hydrophila by intramuscular injection. RESULTS: All fish were fed an identical ratio of commercial pelleted feed relative to biomass. However, in 12/18 tanks, this diet was supplemented with either fresh banana leaves or fresh maize leaves; offered ad libitum. Addition of leaves increased the overall feed conversion ratio (FCR) significantly. However, if only the pellet were taken into account, then no difference was found between treatments. Changes to the isotopic composition of the fish showed leaf nutrient uptake occurred. No prophylactic effects of feeding banana or maize leaves were detected against infection with A. hydrophila, and the diet did not induce changes in the fish haematocrit. However, addition of the maize leaves was associated with significantly reduced severity of the skin lesions, which could improve the market value of the fish. CONCLUSIONS: Addition of the leaf supplement did not result in significantly improved growth performance. Similarly, the effect of the supplement on the fish survival to infection was not significant.
Subject(s)
Aeromonas hydrophila , Carps , Dietary Supplements , Fish Diseases/diet therapy , Gram-Negative Bacterial Infections/veterinary , Musa , Zea mays , Animal Feed , Animals , Carps/growth & development , Carps/microbiology , Disease Susceptibility/veterinary , Fish Diseases/microbiology , Fisheries , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/microbiology , Plant LeavesABSTRACT
ABSTRACT The effect of the ethanolic extract of propolis (EEP) on Aeromonas hydrophila was analyzed by determination of minimum inhibitory concentration (MIC). Then, the effects of crude propolis powder (CPP) on growth, hemato-immune parameters of the Nile tilapia, as well as its effects on resistance to A. hydrophila challenge were investigated. The CPP (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0%) was added to the diet of 280 Nile tilapia (50.0 ± 5.7 g fish-1). Hemato-immune parameters were analyzed before and after the bacterial challenge. Red blood cell, hematocrit, hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and hydrogen peroxide (H2O2) and nitric oxide (NO) were evaluated. The MIC of the EEP was 13% (v/v) with a bactericidal effect after 24 hours. Growth performance was significantly lower for those fish fed diets containing 2.5 and 3% of CPP compared to the control diet. Differences in CPP levels affected fish hemoglobin, neutrophils number and NO following the bacterial challenge. For others parameters no significant differences were observed. Our results show that although propolis has bactericidal properties in vitro, the addition of crude propolis powder to Nile tilapia extruded diets does not necessarily lead to an improvement of fish health.
Subject(s)
Animals , Propolis/administration & dosage , Gram-Negative Bacterial Infections/veterinary , Aeromonas hydrophila/drug effects , Cichlids/microbiology , Fish Diseases/diet therapy , Propolis/therapeutic use , Microbial Sensitivity Tests , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/microbiology , Dietary Supplements , Cichlids/blood , Fish Diseases/microbiology , Immunity, InnateABSTRACT
The effect of the ethanolic extract of propolis (EEP) on Aeromonas hydrophila was analyzed by determination of minimum inhibitory concentration (MIC). Then, the effects of crude propolis powder (CPP) on growth, hemato-immune parameters of the Nile tilapia, as well as its effects on resistance to A. hydrophila challenge were investigated. The CPP (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0%) was added to the diet of 280 Nile tilapia (50.0 ± 5.7 g fish-1). Hemato-immune parameters were analyzed before and after the bacterial challenge. Red blood cell, hematocrit, hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and hydrogen peroxide (H2O2) and nitric oxide (NO) were evaluated. The MIC of the EEP was 13% (v/v) with a bactericidal effect after 24 hours. Growth performance was significantly lower for those fish fed diets containing 2.5 and 3% of CPP compared to the control diet. Differences in CPP levels affected fish hemoglobin, neutrophils number and NO following the bacterial challenge. For others parameters no significant differences were observed. Our results show that although propolis has bactericidal properties in vitro, the addition of crude propolis powder to Nile tilapia extruded diets does not necessarily lead to an improvement of fish health.
Subject(s)
Aeromonas hydrophila/drug effects , Cichlids/microbiology , Fish Diseases/diet therapy , Gram-Negative Bacterial Infections/veterinary , Propolis/administration & dosage , Animals , Cichlids/blood , Dietary Supplements , Fish Diseases/microbiology , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/microbiology , Immunity, Innate , Microbial Sensitivity Tests , Propolis/therapeutic useABSTRACT
Since the use of malachite green was banned, it is desirable to search for alternative drug to control Ichthyophthirius multifiliis infection. Moreover, route of administration which is easy to implement and less stressful to fish is important to treat infection of fish with this parasite. It is also important to enhance protective effect against Aeromonas hydrophila infection after parasitism by I. multifiliis. The present study evaluated the protective effect of diet supplemented with Artemisia annua against I. multifiliis and A. hydrophila infection after the parasitism. The results showed that oral administration with A. annua at a concentration of 20 g/kg feed for 45 days can provide strong protection against I. multifiliis infection. The incidence of infestation and mean number of trophonts on fish fins on day 3 post-challenge (15,000 theronts/fish) were significantly reduced compared with the control, and the survival rate of fish during 15-day period was also increased by nearly 30 %. But, this diet provided very limited protection against higher infection dose. Besides, this study demonstrated that this diet enhanced protective effect against A. hydrophila after the fish were infected with I. multifiliis. On the basis of the above results, oral administration with A. annua can be used as a potential strategy for control I. multifiliis infection and increasing fish survival after parasitism by I. multifiliis.
Subject(s)
Artemisia annua , Ciliophora Infections/veterinary , Fish Diseases/diet therapy , Gram-Negative Bacterial Infections/veterinary , Administration, Oral , Aeromonas hydrophila/physiology , Animals , Ciliophora Infections/diet therapy , Fishes , Gram-Negative Bacterial Infections/diet therapy , Hymenostomatida/physiology , Survival AnalysisABSTRACT
Camu camu, Myrciaria dubia, is an Amazon plant that presents high levels of vitamin C in its composition. Several studies in animals and humans have demonstrated their efficiency in the prevention and treatment of various diseases. However, there are no reports of its properties in fish. The aim of this study was to evaluate the effect of the oral administration of the extract of this plant in the immune parameters in Nile tilapia, Oreochromis niloticus. 400 Nile tilapia (80 ± 5 g) were randomly distributed into 20 tanks with 1500 L capacity each (20 fish/tank). After a week of adaptation to environmental conditions, it was provided a diet for 5 weeks, using different levels of inclusion of camu camu extract: 0, 50, 100, 250, and 500 mg/kg of feed. Each treatment consisted of four replicates. It was obtained 40.5 mg of vitamin C/g of camu camu pulp powder by high-performance liquid chromatography. At the end of the trial period, fish were inoculated with Aeromonas hydrophila in the swim bladder. Samples were taken after 6; 24 and 48 h of the challenge. Results revealed that fish supplemented with this herb showed significant increase (P < 0.05) in white blood cells counts in blood and exudate, burst respiratory activity, lysozyme activity, serum bactericidal activity, direct agglutination, and melanomacrophage centers count. Red blood cells count, hemoglobin, hematocrit, and biochemical profile of fish supplemented with the herb presented no statistical differences compared to control group (P > 0.05). No histopathological lesions were observed in intestine, kidney, spleen, and gills. It can be concluded that the addition of Myrciaria dubia in tilapia feed improves the immune response and the growth after 5 weeks, especially, at a dose of 500 mg/kg.
Subject(s)
Cichlids/immunology , Dietary Supplements , Fish Diseases/diet therapy , Gram-Negative Bacterial Infections/veterinary , Immunity, Innate , Myrtaceae/chemistry , Plant Extracts/metabolism , Aeromonas hydrophila/physiology , Animal Feed/analysis , Animals , Diet/veterinary , Dose-Response Relationship, Drug , Fish Diseases/immunology , Fish Diseases/microbiology , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/immunology , Gram-Negative Bacterial Infections/microbiology , Random AllocationABSTRACT
Abstract The principles of rational antibacterial therapy in children for the burn trauma were analyzed. The results of the completed treatment of 808 children for the burn trauma in a Combustiological Department of Municipal clinical hospital of City of Zaporozhye were studied. In 326 (40.3%) children antibacterial therapy was conducted, including one antibiotic--in 268 (82.2%), two and more--in 37 (11.3%). The preparations were prescribed empirically, taking into account bacteriological profile of the Department and the patients premorbidity background present. Prescription of modern anticlostridial probiotics, containing stamms of Lactobacillus rhamnosus R0011 and Lactobacillus acedofilus R0052, on background of continuing antibacterial therapy, have constituted the effective measure of prophylaxis for the antibiotic-associated diarrhea, as the most frequent complication of antibacterial therapy.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Burns/therapy , Gram-Negative Bacterial Infections/drug therapy , Gram-Positive Bacterial Infections/drug therapy , Probiotics/therapeutic use , Skin Transplantation/methods , Burns/microbiology , Burns/pathology , Burns/surgery , Child , Child, Preschool , Combined Modality Therapy , Diarrhea/diet therapy , Diarrhea/microbiology , Diarrhea/prevention & control , Female , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/microbiology , Gram-Positive Bacterial Infections/diet therapy , Gram-Positive Bacterial Infections/microbiology , Humans , Infant , Infant, Newborn , Lactobacillus acidophilus/physiology , Lacticaseibacillus rhamnosus/physiology , Male , Transplantation, Autologous , Treatment OutcomeABSTRACT
PURPOSE: Conflicting reports exist regarding the surgical indications, timing, approach, staged or not operation, and spinal instrumentation for patients with spondylodiscitis. Therefore, we performed this study to evaluate the outcome of a series of patients with spondylodiscitis aiming to answer when and how to operate on these patients. MATERIALS AND METHODS: We retrospectively studied the files of 153 patients with spondylodiscitis treated at our institution from 2002 to 2012. The approach included MR imaging of the infected spine, isolation of the pathogen with blood cultures and/or biopsy, and further conservative or surgical treatment. The mean follow-up was 6 years (range 1-13 years). We evaluated the indications, timing (when), and methods (how) for surgical treatment, and the clinical outcome of these patients. RESULTS: Orthopedic surgical treatment was necessary for 13 of the 153 patients (8.5 %). These were patients with low access to healthcare systems because of low socioeconomic status, third-country migrants, prisoners or intravenous drug use, patients in whom a bacterial isolate documentation was necessary, and patients with previous spinal operations. The most common pathogen was Mycobacterium tuberculosis. The surgical indications included deterioration of the neurological status (11 patients), need for bacterial isolate (10 patients), septicemia due to no response to antibiotics (five patients), and/or spinal instability (three patients). An anterior vertebral approach was more commonly used. Nine of the 13 patients had spinal instrumentation in the same setting. Improvement or recovery of the neurological status was observed postoperatively in all patients with preoperative neurological deficits. Postoperatively, two patients deceased from pulmonary infection and septicemia, and heart infarction. At the last follow-up, patients who were alive were asymptomatic; ten patients were neurologically intact, and one patient experienced paraparesis. Imaging showed spinal fusion, without evidence of recurrent spondylodiscitis. Complications related to the spinal instrumentation were not observed in the respective patients. CONCLUSIONS: Conservative treatment is the standard for spondylodiscitis. Physicians should be alert for Mycobacterium tuberculosis spondylitis because of the low access to healthcare systems of patients with low social and economic status. Surgical indications include obtaining tissue sample for diagnosis, occurrence or progression of neurological symptoms, failure of conservative treatment, large anterior abscesses, and very extensive disease. Thorough debridement of infected tissue and spinal stability is paramount. The anterior approach provides direct access and improved exposure to the most commonly affected part of the spine. Spinal instrumentation is generally recommended for optimum spinal stability and fusion, without any implant-related complications.
Subject(s)
Discitis/surgery , Adult , Aged , Anti-Bacterial Agents/therapeutic use , Biopsy , Candida albicans/isolation & purification , Candidiasis, Invasive/drug therapy , Candidiasis, Invasive/microbiology , Candidiasis, Invasive/surgery , Clinical Decision-Making , Debridement/methods , Discitis/drug therapy , Discitis/microbiology , Follow-Up Studies , Gram-Negative Bacteria/isolation & purification , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/microbiology , Gram-Negative Bacterial Infections/surgery , Gram-Positive Bacteria/isolation & purification , Gram-Positive Bacterial Infections/drug therapy , Gram-Positive Bacterial Infections/microbiology , Gram-Positive Bacterial Infections/surgery , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Nervous System Diseases/drug therapy , Nervous System Diseases/microbiology , Nervous System Diseases/surgery , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome , Tuberculosis, Spinal/drug therapy , Tuberculosis, Spinal/microbiology , Tuberculosis, Spinal/surgeryABSTRACT
The present study aimed to investigate the effects of Chlorophytum borivilianum polysaccharide (CBP), as a dietary supplement administered at varying concentrations with feed (basal diet), on various cytokine-related responses in Labeo rohita fingerlings. Immune parameters and immune-related gene expressions were measured at 3rd, 4th, and 5th week after feeding. The results revealed that dietary administration of CBP at 0.2% and 0.4% for 4 weeks significantly upregulated serum lysozyme and phagocytic activity. Complement C3 and respiratory burst activity (RBA) were significantly higher after 4 weeks of CBP feeding. The immune related genes IL-8, IL-1ß, TNF-α, and iNOS were downregulated (P < 0.05) in groups with 0.2% and 0.4% CBP supplemented diets at week 4. Expression of anti-inflammatory cytokines (IL-10 and TGF-ß) was also downregulated (P < 0.5) after 4 weeks of feeding with 0.2% to 0.8% CBP. However, five weeks of CBP administration had no significant effect on immune gene expression, except TNF-α and IL-8. Fish fed with 0.4% CBP for 4 weeks showed maximum resistance against Aeromonas hydrophila (73.3% survival) compared to control. From these results, we recommend that CBP administration at 0.4% for 4 weeks could effectively improve immune response and disease resistance in L. rohita.
Subject(s)
Dietary Supplements , Fish Diseases/diet therapy , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/veterinary , Immunity, Innate/drug effects , Polysaccharides/pharmacology , Aeromonas hydrophila/immunology , Aeromonas hydrophila/pathogenicity , Animal Feed , Animals , Complement C3/genetics , Cyprinidae , Disease Resistance/drug effects , Fish Diseases/immunology , Fish Diseases/microbiology , Fish Diseases/mortality , Gene Expression Regulation , Gram-Negative Bacterial Infections/immunology , Gram-Negative Bacterial Infections/mortality , Interleukin-10/genetics , Interleukin-10/immunology , Interleukin-1beta/genetics , Interleukin-1beta/immunology , Interleukin-8/genetics , Interleukin-8/immunology , Liliaceae/chemistry , Muramidase/genetics , Muramidase/immunology , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/immunology , Phagocytosis/drug effects , Polysaccharides/isolation & purification , Respiratory Burst/drug effects , Survival Analysis , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/immunology , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunologyABSTRACT
Celiac disease is a multifactorial disorder that involves interactions between genetic and environmental factors. Gluten proteins are responsible for the symptoms of celiac disease, but other environmental factors that influence the intestinal ecosystem, including the milk-feeding type and gastrointestinal infections, may also play a role. Moreover, intestinal dysbiosis, characterized by increased Gram-negative bacteria and reduced bifidobacteria, has been detected in celiac disease patients. This review summarizes current knowledge of the associations between the intestinal microbiota and celiac disease and its possible modes of action in pathogenesis. Deeper understanding of these interactions can help redefine how this disorder is investigated.
Subject(s)
Celiac Disease/microbiology , Gram-Negative Bacteria/immunology , Gram-Negative Bacterial Infections/microbiology , Intestines/microbiology , Metagenome , Animals , Antibiosis/immunology , Celiac Disease/diet therapy , Celiac Disease/immunology , Diet Therapy , Gram-Negative Bacteria/pathogenicity , Gram-Negative Bacterial Infections/complications , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/immunology , Humans , Immune Tolerance , Immunity, Mucosal , Inflammation/microbiology , Intestines/immunology , Metagenome/immunology , Probiotics/administration & dosage , Symbiosis/immunology , VirulenceABSTRACT
Garlic, Allium sativum, which was fed at 0, 0.05, 0.1, 0.5 and 1.0 g per 100 g of feed for 14 days to rainbow trout, Oncorhynchus mykiss (Walbaum), led to control of experimental infection with Aeromonas hydrophila. At doses of 0.5 and 1.0 g garlic per 100 g of feed, there was a reduction in mortalities to 4% compared with the controls (88%). Moreover, there was a significant increase in growth, feed conversion and protein efficiency. There was stimulation of the number of erythrocytes and leucocytes, a significantly higher haematocrit, enhancement of phagocytic activity, respiratory burst, lysozyme, anti-protease and bactericidal activities following feeding with garlic.
Subject(s)
Aeromonas hydrophila/physiology , Dietary Supplements , Fish Diseases/diet therapy , Garlic , Gram-Negative Bacterial Infections/veterinary , Immunity, Innate/immunology , Oncorhynchus mykiss/immunology , Animals , Blood Cell Count , Diet/veterinary , Fish Diseases/immunology , Fish Diseases/mortality , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/immunology , Gram-Negative Bacterial Infections/mortality , Muramidase/blood , Oncorhynchus mykiss/growth & development , Phagocytosis/immunology , Random Allocation , Superoxides/bloodABSTRACT
Ginger, Zingiber officinale, which was fed at 0, 0.05, 0.1, 0.5 and 1.0 g per 100 g of feed for 14 days to rainbow trout, Oncorhynchus mykiss (Walbaum), led to control of experimental infection with Aeromonas hydrophila. At 0.5 g ginger per 100 g of feed, there was a reduction in mortalities to 0% compared with the controls (64%). Moreover, there was a significant increase in growth, feed conversion and protein efficiency. There was proliferation in the number of neutrophils, macrophages and lymphocytes, and enhanced phagocytic, respiratory burst, lysozyme, bactericidal and anti-protease activities compared with the controls.
Subject(s)
Adjuvants, Immunologic/administration & dosage , Aeromonas hydrophila/physiology , Dietary Supplements , Fish Diseases/diet therapy , Gram-Negative Bacterial Infections/veterinary , Oncorhynchus mykiss/immunology , Zingiber officinale , Animals , Blood Cell Count , Colony Count, Microbial , Diet/veterinary , Gram-Negative Bacterial Infections/diet therapy , Hemoglobins/analysis , Immunity, Innate/immunology , Muramidase/blood , Oncorhynchus mykiss/growth & development , Phagocytosis/immunology , Superoxides/bloodABSTRACT
Motile aeromonad septicaemia caused by Aeromonas sobria is a cause of disease in farmed perch, Perca fluviatilis L., in Switzerland. We have evaluated the potential of a Pseudomonas chlororaphis isolate, obtained from perch intestine, to control A. sobria infection. Inoculation of juvenile perch with P. chlororaphis strain JF3835 prior to infection with A. sobria caused a reduction in A. sobria associated mortalities. Infection of perch with xylE-labelled P. chlororaphis indicated the bacterium is able to transiently colonize juvenile fish and fingerlings.
Subject(s)
Aeromonas , Fish Diseases/diet therapy , Fish Diseases/microbiology , Gram-Negative Bacterial Infections/veterinary , Perches , Probiotics/therapeutic use , Pseudomonas/physiology , Animals , Fish Diseases/mortality , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/microbiology , Gram-Negative Bacterial Infections/mortality , Microbial Sensitivity Tests/veterinary , SwitzerlandABSTRACT
A 60-day feeding trial was conducted to study the immuno-protective effect of microbial levan on Labeo rohita juveniles challenged with Aeromonas hydrophila. Six purified diets were prepared with different levels of microbial levan: control (no levan), T1 (Basal + 0.25%), T2 (Basal + 0.50%), T3 (Basal + 0.75%), T4 (Basal + 1%) and T5 (Basal + 1.25%), fed to six groups of fish in triplicate. Among the treatment groups the haemoglobin content and total leucocyte count were increased with a dietary supplementation of levan at 1% or more. An increasing trend for total erythrocyte count was observed with increasing level of dietary levan. Lower levan-supplemented groups showed a higher albumin/globulin ratio. As the levan supplementation was increased, there was a gradual increase in serum lysozyme activity and respiratory burst activity [nitroblue tetrazolium (NBT) assay] reduction values. The highest lysozyme activity and NBT were observed in the T5 group although this was similar to the T4 group (P > 0.05). No significant histo-architectural changes were associated with dietary levan levels. After challenge with A. hydrophila, moderately degenerated hepatocytes, oedema and leucocytic infiltration in parenchymatous tissues, and extensive haemorrhage and haemosiderosis in the kidney were observed in the control group. However, the T5 group supplemented with 1.25% levan showed infiltrating leucocytes in the liver while the kidney showed only moderate degeneration of renal tubules. The relative survival per cent of juveniles after challenge with A. hydrophila was the highest in the T5 group followed by T4. This suggests that microbial levan at 1.25% can be used as dietary immunostimulant for L. rohita juveniles.
Subject(s)
Aeromonas hydrophila/physiology , Cyprinidae/immunology , Fish Diseases/diet therapy , Fructans/pharmacology , Gram-Negative Bacterial Infections/veterinary , Immunity, Innate/drug effects , Probiotics/pharmacology , Animals , Diet , Fish Diseases/immunology , Fish Diseases/mortality , Fish Diseases/pathology , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/immunology , Gram-Negative Bacterial Infections/pathology , Hepatocytes/drug effects , Hepatocytes/pathology , Kidney/drug effects , Kidney/pathology , Liver/drug effects , Liver/pathology , Muramidase/blood , Respiratory Burst/drug effects , Survival AnalysisABSTRACT
A feeding trial was conducted for 60 days to delineate the effect of dietary ribonucleic acid or chitin on haematological parameters, phagocyte respiratory burst and resistance to Aeromonas hydrophila of Labeo rohita juveniles. One hundred and twenty-six (avg. wt. 13.40 +/- 0.17 g) juveniles were randomly distributed in six treatment groups, each one in three replicates. Six isonitrogenous (crude protein: 34.34-35.37%) and isocaloric (414-425 kcal 100 g(-1)) purified diets were prepared with different concentrations of either ribonucleic acid or chitin except the control group, viz., control, T1 (0.1% ribonucleic acid), T2 (0.2% ribonucleic acid), T3 (0.4% ribonucleic acid), T4 (25 mg chitin kg (-1)) and T5 (50 mg chitin kg (-1)). Weight gain %, specific growth rate, feed efficiency ratio, protein efficiency ratio did not vary significantly (P > 0.05) among the experimental groups. Haemoglobin content and total erythrocyte count were observed within the normal range and were not influenced by the dietary immunostimulants. Highest total leukocyte count was found in the T(3) group. The immunomodulatory effects of dietary immunostimulants were studied by using nitroblue tetrazolium (NBT) assay and serum parameters, namely total protein, albumin, globulin and A/G ratio. The respiratory burst activity (NBT) of blood phagocytes was highest in the T3 group followed by the T2 group, which varied significantly (P < 0.05) from other groups. Significantly (P < 0.05) higher total protein, globulin and lower A/G ratio was observed in the T(3) group. The relative percent survival after challenging with Aeromonas hydrophila was highest in the T3 group, compared to the control group, followed by the T2 group. The results indicate that dietary ribonucleic acid at 0.4% enhances phagocyte respiratory burst and protection of Labeo rohita juveniles to challenge by A. hydrophila.
Subject(s)
Aeromonas hydrophila , Carps , Fish Diseases/diet therapy , Fish Diseases/microbiology , Gram-Negative Bacterial Infections/veterinary , RNA/administration & dosage , Analysis of Variance , Animals , Blood Cell Count , Body Weight , Chitin/administration & dosage , Chitin/pharmacology , Fish Diseases/immunology , Fresh Water/analysis , Gram-Negative Bacterial Infections/diet therapy , Gram-Negative Bacterial Infections/immunology , Hemoglobins/metabolism , Immunity, Innate/drug effects , Leukocytes/drug effects , Nitroblue Tetrazolium , Phagocytes/drug effects , RNA/pharmacology , Respiratory Burst/drug effects , Yeasts/geneticsABSTRACT
BACKGROUND: Tunneled dialysis catheters are complicated by frequent systemic infections. Standard therapy of catheter-associated bacteremia involves both systemic antibiotics and catheter replacement. Recent data suggest that biofilms in the catheter lumen are responsible for the bacteremia, and that instillation of an antibiotic lock (highly concentrated antibiotic solution) into the catheter lumen after dialysis sessions can eradicate the biofilm. METHODS: We analyzed prospectively the efficacy of an antibiotic lock protocol, in conjunction with systemic antibiotics, for treatment of patients with dialysis catheter-associated bacteremia without catheter removal. Protocol success was defined as resolution of fever and negative surveillance cultures one week following completion of the protocol. Protocol failure was defined as persistence of fever or surveillance cultures positive for any pathogen. In addition, infection-free catheter survival was compared to that observed in institutional historical control patients treated with catheter replacement. RESULTS: Blood cultures were positive in 98 of 129 of episodes (76%) in which patients dialyzing with a catheter had fever or chills. Protocol success occurred in 40 of 79 infected patients (51%) treated with the antibiotic lock. Protocol failure occurred in 39 cases (49%): 7 had persistent fever, 15 had positive surveillance cultures (9 for Candida and 6 for bacteria), and 17 required catheter removal due to malfunction. Each of the pathogens in the surveillance cultures was different from the original pathogen in that patient. Eight of the 9 secondary Candida infections and all 6 secondary bacterial infections resolved after catheter exchange and specific antimicrobial treatment. Overall catheter survival with the antibiotic lock protocol was similar to that observed among patients managed with catheter replacement (median survival, 64 vs. 54 days, P = 0.24). CONCLUSIONS: Use of an antibiotic lock, in conjunction with systemic antibiotic therapy, can eradicate catheter-associated bacteremia while salvaging the catheter in about one half of cases. Moreover, this management approach offers clinical advantages over routine catheter exchange.