Chellam Balasundaram

Effect of chemotherapy, vaccines and immunostimulants on innate immunity of goldfish infected with Aeromonas hydrophila

We report the effect of various chemicals, vaccines and immunostimulants on innate immune mechanisms such as phagocytosis activity, superoxide anion production of blood leukocytes, complement activity and plasma lysozyme activity and disease resistance in goldfish Carassius auratus (23 +/- 2 g) against Aeromonas hydrophila on Days 15 and 30 post-infection. In infected fish, the administration of diets supplemented with either probiotics, tri-herbal extract or azadirachtin for 30 d significantly enhanced phagocytic activity; administration for 15 d had no effect. In fish treated with heat-killed and formalin-killed vaccines, and probiotics-, tri-herbal- and azadirachtin-supplemented diets, superoxide anion production was enhanced on Day 30. However, there was no superoxide anion production in fish treated with tetracycline, furanace, formalin or hydrogen peroxide. Complement activity was also significantly enhanced on Days 15 and 30 in fish groups treated with vaccine and probiotics-, tri-herbal- and azadirachtin-supplemented diets. Other groups had no complement activity. Lysozyme activity was significantly enhanced after 30 d in fish treated with heat-killed vaccine and probiotics-, tri-herbal- and azadirachtin-supplemented diets. The probiotics- and tri-herbal-containing diet administration groups had no mortality (0%) preceding the challenge with live A. hydrophila. Groups treated with heat- or formalin-killed vaccines or azadirachtin-supplemented diet suffered mortalities of 30, 35 and 10%, respectively, which represents an improvement of survival rate compared to untreated infected control groups. We conclude that probiotics-, tri-herbal- and azadirachtin-supplemented diets act as immunostimulants enhancing the goldfish innate immune response and disease resistance against A. hydrophila.

Potential use of probiotic- and triherbal extract-enriched diets to control Aeromonas hydrophila infection in carp

This study reports the effect of probiotic- and triherbal extract-enriched diet on Cyprinus carpio (52 +/- 2 g, n = 250) inoculated intramuscularly (50 microl) with Aeromonas hydrophila (1.8 x 106 CFU ml(-1)). On Day 6 post-infection, the fish were divided into 4 groups and fed with the basal diet (IU) or with diets supplemented with triherbal extract (H), Sporolac (S) or Lactobacillus (L). A fifth group of non-infected fish fed with the basal diet was used as a control. Haematology and immunology parameters were measured in Weeks 1, 2 and 4. In the H, S, and L groups, white blood cell levels were significantly increased (p < 0.05) throughout the experimental period. In the H and S groups, red blood cell and haemoglobin levels decreased significantly (p < 0.05) in Weeks 1, 2 and 4. In all the diet groups, the haematocrit and mean corpuscular volume did not differ significantly (p > 0.05) in Week 1, and these values remained near those of the control in Week 2. The S and L groups did not exhibit significant changes (p > 0.05) in glucose, and cholesterol levels in Weeks 2 and 4 compared to controls, and the L group also showed no change in total protein. Respiratory burst activity was significantly increased in Weeks 1 to 4 in the H, S and L groups. Serum-mediated killing of Escherichia coli was significantly increased in the L group in Weeks 1 to 4. Mortalities after A. hydrophila challenge were higher in the IU (85%) and H (50%) groups than in the S (45%) and L (35%) groups. Our results show that formulated probiotic-enriched diets can speed up the recovery of ulcerative dermatitis induced by A. hydrophila in carp.

Immune response and disease resistance of carotenoids supplementation diet in Cyprinus carpio against Aeromonas hydrophila.

The effect of carotenoid-supplementation diet on immune response and disease resistance in common carp, Cyprinus carpio against Aeromonas hydrophila at weeks 1, 2, and 4 is reported. The cumulative mortality was 10% when fish were fed with 50 or 100 mg kg(-1) supplementation diets while the un-supplementation diet treated group suffered 90% mortality against the pathogen. The phagocytic activity and complement activity significantly increased with 50 and 100 mg kg(-1) diet groups from weeks 2 and 4 but not in other groups. The reactive oxygen species (ROS) production was significantly enhanced with 50 and 100 mg kg(-1) diets from weeks 1 to 4 while the production of reactive nitrogen species (RNS) enhanced on weeks 2 and 4. The lysozyme activity significantly increased when fed with 50 and 100 mg kg(-1) diets on weeks 2 and all supplementation diets on week 4. These results suggest that diet enriched with carotenoid pigment positively enhance the immune status and protects C. carpio from A. hydrophila infection.

Dietary supplementation of Avicennia marina extract on immune protection and disease resistance in Amphiprion sebae against Vibrio alginolyticus

The effect of Avicennia marina aqueous leaf extract on innate immune mechanisms such as total white blood cell counts (WBC), serum lysozyme activity, respiratory burst assay, alternative complement (ACH50) assay, phagocytic activity assay, disease resistance, gut bacteria, and survival rate of clownfish (Amphiprion sebae) against Vibrio alginolyticus is reported. Healthy fish challenged with V. alginolyticus (1 × 10(7) cells ml(-1)) were fed with diets supplemented (0, 1, 2, and 4%) with A. marina extract. The survival rate was 85% and 80% in infected fish fed with 4% and 8% supplementation diet; with 1% diet it was 70% while in the infected untreated group it was only 10%. The total gut bacteria flora was high in 8% and 4% supplementation diet groups with 2.8 × 10(5) and 4.7 × 10(4) cfu/g while it was 8.9 × 10(3) cfu/g in 1% diet group. The immunological parameters significantly increased on weeks 6 and 8 when infected fish were fed with 1% or 4% supplementation diet. This study reports that in clownfish challenged with V. alginolyticus, dietary administration of the 1% or 4% of A. marina extract improved the immune status and survival rate.

Protective effect of chitin and chitosan enriched diets on immunity and disease resistance in Cirrhina mrigala against Aphanomyces invadans

The effect of diet enriched with 1% chitin or chitosan on innate immune response and disease resistance in Cirrhina mrigala against Aphanomyces invadans was investigated at weeks 1, 2, and 4. In the un-infected and infected groups the white blood cells (WBC), red blood cells (RBC), haematocrit (Ht), lympocytes, monocytes, and neutrophils significantly increased when fed with 1% chitin (CH) or chitosan (CT) enriched diet from weeks 1 to 4 when compared to control; however, the haemoglobin (Hb) and thrombocytes significantly increased only on weeks 2 and 4. The total protein and albumin levels also significantly increased with any enriched diet on weeks 2 and 4; but the globulin and albumin:globulin ratio increased on week 4 as compared to control; similarly the phagocytic activity significantly increased on weeks 2 and 4 while the lysozyme activity increased from weeks 1 to 4. The complement activity was significantly enhanced in CT and CTI fed groups on weeks 2 and 4. In un-infected fish fed with 1% CH and CT diets, the cumulative mortality was 10% and 5% whereas the infected fish suffered 20% and 25% mortality. The present results suggest that infected fish fed with 1% chitin or chitosan enriched diet modulates the immune system conferring disease resistance in C. mrigala against A. invadans.

Phytotherapy of ulcerative dermatitis induced by Aeromonas hydrophila infection in goldfish ( Carassius auratus ).

Goldfish ( Carassius auratus ) weighing 13 +/- 2 g were administered intramuscularly a sublethal dose (1.8 x 10 3 cfu/ml) of Aeromonas hydrophila to induce ulcerative dermatitis. On day 3 and day 6 after infection the fish were dip-treated (for 5 min/day) with a tri-herbal concoction of Curcuma longa, Ocimum sanctum and Azadirachta indica (1%). The LD 50 value was recorded at a concentration of 2.3 x 10 4 between 30 and 36 days after infection. In the infected untreated group the cumulative mortality was higher, while in the early-treated group (day 3) there was no mortality. In the late-treated group (6th day) the mortality increased to 23.3% on day 36. In the infected group the size of ulcers progressively increased from 43.3% of the body length on day 18 to 86.7% on day 36. In the early-treated fish the size of ulcers was 23.3% of the body length on day 18; by day 36 after treatment the ulcer had completely healed. In contrast, there was only a moderate recovery in the late-treated group. From the results it can be concluded that early tri-herbal treatment ensures successful recovery from ulcerative dermatitis induced by A. hydrophila .

Effect of Shilajit enriched diet on immunity, antioxidants, and disease resistance in Macrobrachium rosenbergii (de Man) against Aeromonas hydrophila

The effect of diet supplemented with Shilajit, a multi-component natural mineral substance on the antioxidant activity, immune response, and disease resistance in freshwater prawn, Macrobrachium rosenbergii (de Man) against Aeromonas hydrophila is reported. The total hemocyte count (THC) and phagocytic activity significantly increased with 2xa0gxa0kg(-1) supplemented diet on first week and with other enriched diets on weeks 2 and 4. The respiratory burst (RB) activity and glutathione peroxidase (GPx) activity were significantly increased with 2xa0gxa0kg(-1) supplemented diet on weeks 1 and 2 whereas 2 and 4xa0gxa0kg(-1) diets on week 4. The phenoloxidase (PO) activity increased significantly with 2xa0gxa0kg(-1) diet only on second week and with other enriched diets only on fourth week. The superoxide dismutase (SOD) activity increased significantly with any enriched diet during the experimental period except with 6xa0gxa0kg(-1) diets on first week. However, the glutathione reductase (GR) activity was enhanced significantly only with 2xa0gxa0kg(-1) enriched diets on weeks 2 and 4. The cumulative mortality of the prawn fed with 2 and 4xa0gxa0kg(-1) enriched diets was 10% and 15% whereas with 6xa0gxa0kg(-1) diet the mortality was 20%. The results suggest that diet enriched with Shilajit at 2xa0gxa0kg(-1) or 4xa0gxa0kg(-1) positively enhances the antioxidant activity, immunity, and disease resistance in M.xa0rosenbergii against A.xa0hydrophila.

Dietary supplementation of Zeolite on growth performance, immunological role, and disease resistance in Channa striatus against Aphanomyces invadans.

Epizootic Ulcerative Syndrome (EUS) caused by Aphanomyces invadans which is a primary fungal parasitic pathogen, inflicts serious economic loss in tropical freshwater fish including snakehead murrel, Channa striatus. In the present study with an aim to circumvent the adverse effects of the traditional measures in graded levels (2%, 4%, and 6%) of Zeolite enriched diet on growth performance, hematology, immunological response, and disease resistance in C.xa0striatus against A.xa0invadans is reported. The final weight (FW), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER), and average daily gain (ADG) were significantly high in infected fish fed with 4% or 6% Zeolite incorporated diets on 4th week. The maximum survival rates (SR) of 96% and 98% were observed when fed with 2% or 4% diets on 4th week. Similarly, the white blood cell (WBC), red blood cell (RBC), hematocrit (Hct), mean corpuscular volume (MCV), and mean corpuscular haemoglobin concentration (MCHC) were significantly high when fed with any Zeolite enriched diet. However, the haemoglobin (Hb) and mean corpuscular haemoglobin (MCH) were significantly high with 4% and 6% Zeolite diets. The total protein and globulin were significantly high with 4% and 6% diets; the albumin, glucose, cholesterol, and triglyceride were significantly elevated with any enriched diet. The 4% and 6% Zeolite diets significantly enhanced the phagocytic activity on 2nd week but the 2% diet could increase it on 4th week. The respiratory burst (RB) activity, complement activity, and lymphocyte proliferation level were significantly enhanced with 4% and 6% Zeolite diets on weeks 1 and 2 while with 2% diet on 4th week. All enriched diets significantly increased the lysozyme activity during the experimental period. Superoxide anion (SOA) production significantly enhanced with 6% diet on weeks 1 and 2 whereas with 2% diet on week 4. Lower cumulative mortality of 10% and 15% was found with 4% and 6% Zeolite diets whereas a higher mortality (20%) was observed with 2% diet. The present study suggests that dietary supplementation with 4% or 6% Zeolite significantly increase growth performance, hemato-biochemical changes, immunological response, and disease resistance in C.xa0striatus against A.xa0invadans.

Comparison of fatty acid profile of wild and farm reared freshwater prawn Macrobrachium rosenbergii (De Man) brooders for broodstock diet formulation

Fatty acid profiles of midgut gland (MG), ovary and eggs of Macrobrachium rosenbergii of wild and farm reared brooders indicate a significant variation of their components during the sexual maturation and spawning. In both groups, major fatty acids found in the chosen tissues were 14:0, 16:0, 18:0, 18:1n-9, 18:2n-6, 18:3n-3, 20:4n-6, 20:5n-3 and 22:6n-3. Of these, saturated fatty acids dominate over the mono-unsaturated (MUFA), polyunsaturated (PUFA) and highly unsaturated fatty acids (HUFA). Though all the four groups of fatty acids are found in both groups except n-3 HUFA (P>0.05) other categories are found in higher wild brooders (P 0.05). n n xa0 n n Key words: Fatty acids profile, morphometry, Macrobrachium rosenbergii, wild and farm brooders.

Immune defense of emodin enriched diet in Clarias batrachus against Aeromonas hydrophila

&NA; This study investigates the effect of emodin enriched diet on growth, hematology, and immune response in walking catfish, Clarias batrachus against Aeromonas hydrophila. The basal (control) diet supplemented with emodin at 0.0, 0.1, 0.2, or 0.4 g kg−1 was fed to the experimental groups for a period of four weeks. Feeding infected fish with 0.2 g kg−1 and 0.4 g kg−1 emodin enriched diets resulted in an overall weight gain, enhanced PER and FCR when compared to other diets. The survival rates were 98.3% and 96.7% in 0.1 g kg−1 and 0.4 g kg−1 emodin diet fed groups. Feeding with 0.2 g kg−1 diet the RBC level significantly elevated on week 1 and with 0.4 g kg−1 diet on weeks 2 and 4. The WBC, the percentage of globulin and neutrophils increased significantly with 0.2 g kg−1 diet only on week 4; however with 0.4 g kg−1 diet the increase was observed from week 1–4. The phagocytic activity increased significantly on being fed with 0.4 g kg−1 diet on week 2 while with 0.2 g kg−1 and 0.4 g kg−1 diets the increase manifested only on week 4; the respiratory burst activity also significantly increased on week 4 whereas increased the complement activity on weeks 2 and 4. The superoxide dismutase (SOD) activity was high on being fed with 0.4 g kg−1 diet on week 1; with 0.2 g kg−1 or 0.4 g kg−1 diets the increase was observed on weeks 2 and 4. The serum IgM level significantly increased when fed with 0.4 g kg−1 diet whereas the lysozyme activity was enhanced with 0.2 g kg−1 and 0.4 g kg−1 emodin diets on weeks 2 and 4. The percentage cumulative mortality was 10% with 0.1 g kg−1 or 0.2 g kg−1 diets while with 0.2 g kg−1 diet it was 15%. The results demonstrate that as a feed additive emodin acts as an immunostimulant enhancing the specific and nonspecific immune defense affording increased disease protection, enhances better growth and boosts hematology parameters in C. batrachus against A. hydrophila infection. HighlightsThe better weight gain was found with 0.2 and 0.4 g kg−1 diets for 4 weeks.Survival rates were found 98.3% and 96.7% with 0.1 and 0.4 g kg−1 emodin diets.RBC increased with 0.2 g kg−1 diet on week 1 and 0.4 g kg−1 diet on weeks 2 and 4.Phagocytic activity increased with 0.2 and 0.4 g kg−1 diets on week 4.Lysozyme activity enhanced with 0.2 and 0.4 g kg−1 diets on weeks 2 and 4.