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Priyadarshini SK, Murugesan M, Michael RD, Aiya Subramani P, Rajendran P. Oral administration of terpenoids and phenol fraction of Padina gymnospora stimulates the nonspecific immune response and expression of immune genes, and protects the common carp (Cyprinus carpio) from experimental Aeromonas hydrophila infection. FISH & SHELLFISH IMMUNOLOGY 2023; 142:109141. [PMID: 37802262 DOI: 10.1016/j.fsi.2023.109141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 10/01/2023] [Accepted: 10/03/2023] [Indexed: 10/08/2023]
Abstract
Common carp (Cyprinus carpio), a valuable aquaculture species susceptible to various infections, requires effective immune enhancement strategies. This study investigates the immunomodulatory effects of orally administered terpenoids and phenol fraction (TPF) from Padina gymnospora in C. carpio, focusing on stimulation of nonspecific immune response, immune gene expression, and protection against experimental infection. P. gymnospora is a brown seaweed species known for its bioactive compounds and medicinal properties. TPF was extracted using the Harborne fractionation method, and the presence of terpenoids and phenol compounds was confirmed by qualitative analysis and high-performance thin layer chromatography (HPTLC). TPF was administered orally in different doses to carp. Nonspecific immune responses were evaluated by measuring cellular ROS, RNI, and peroxidase production. The expression of immune genes (lysozyme and interleukin-1β) was assessed by reverse transcriptase PCR. Furthermore, the protective efficacy of TPF was determined by infecting carp with a virulent pathogen, Aeromonas hydrophila, and monitoring mortality rates and disease symptoms. The results demonstrate that oral TPF administration significantly enhances nonspecific immune responses, with increased ROS, RNI, and peroxidase production, indicating improved immune function. Expression levels of lysozyme and interleukin-1β were upregulated, suggesting immune system activation. Moreover, TPF exhibited significant protection against experimental infection, with lower mortality rates compared to the control group. These findings highlight TPF's potential as an effective immunostimulatory agent, enhancing immune responses and providing infection protection in carp. In conclusion, oral TPF administration stimulates nonspecific immune responses, modulates immune gene expression, and confers protection against experimental infection in carp, displaying its potential for enhancing immune responses and disease resistance in aquaculture species, and contributing to sustainable fish health management.
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Affiliation(s)
| | - Monica Murugesan
- Department of Zoology and Research Centre, Lady Doak College, Madurai, Tamil Nadu, 625002, India
| | - R Dinakaran Michael
- Centre for Fish Immunology, Vels Institute of Science, Technology, and Advanced Studies, Chennai, Tamil Nadu, 600117, India
| | - Parasuraman Aiya Subramani
- Department of Fisheries Ecology, Johann Heinrich von Thünen-Institut, Herwigstraße 31, 27572, Bremerhaven, Germany.
| | - Priyatharsini Rajendran
- Department of Zoology and Research Centre, Lady Doak College, Madurai, Tamil Nadu, 625002, India.
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Gao Z, Yang C, Zhang X, Hu B, Zhang H, Zhang Z, Kuang W, Zheng Q, Cao J. Establishment of a Rapid LAMP Assay for Aeromonas hydrophila and Comparison with the Application of qPCR. Metabolites 2023; 13:841. [PMID: 37512548 PMCID: PMC10383757 DOI: 10.3390/metabo13070841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/30/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
The development of an exceptionally sensitive diagnostic technique for early identification of aquaculture diseases, specifically Aeromonas hydrophila, is essential for efficient management of disease outbreaks at aquaculture locations. In this research, a swift and sensitive diagnostic assay employing Loop-mediated isothermal amplification (LAMP) of Aeromonas hydrophila was devised and compared to the conventional qPCR method documented by Rong Wang. Validation of the diagnostic assay was carried out using actual samples obtained from aquaculture fish. The findings revealed that based on the rapid detection of crude bacterial genomic DNA, the fluorescent LAMP assay possessed a lower limit of detection (LOD) of 0.559 ng/μL (0.315-1.693, 95% CI), while the LOD for qPCR stood at 4.301 ng/μL (2.084-8.876, 95% CI). Both techniques demonstrated outstanding specificity, exhibiting no cross-reactivity with bacteria from the same or closely related genera. A total of 74 fish samples suspected to be infected with the fish disease were gathered, with 26 and 23 samples testing positive for Aeromonas hydrophila via LAMP and qPCR, respectively. The concordance analysis for LAMP and qPCR methods generated a Kappa value of 0.909 (0.778-1.000, 95% CI), signifying a high degree of diagnostic consensus. This study highlights that the LAMP assay eliminates the thermal cycle temperature change process of qPCR, uses lysate to crudely extract bacterial genomic DNA, and can complete the detection within 40 min, rendering it a practical and efficient alternative for monitoring disease outbreaks at aquaculture sites.
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Affiliation(s)
- Zihui Gao
- Key Laboratory of Biotechnology and Bioresources Utilization of Ministry of Education, College of Life Science, Dalian Minzu University, Dalian 116600, China
| | - Chunhua Yang
- Institute of Biological Resources, Jiangxi Academy of Sciences, Nanchang 330096, China
| | - Xiaobo Zhang
- Key Laboratory of Biotechnology and Bioresources Utilization of Ministry of Education, College of Life Science, Dalian Minzu University, Dalian 116600, China
| | - Bing Hu
- Key Laboratory of Biotechnology and Bioresources Utilization of Ministry of Education, College of Life Science, Dalian Minzu University, Dalian 116600, China
| | - Huang Zhang
- Guangzhou Double Helix Gene Technology Co., Ltd., Guangzhou 510320, China
| | - Zhihong Zhang
- Institute of Biological Resources, Jiangxi Academy of Sciences, Nanchang 330096, China
| | - Wendong Kuang
- Institute of Biological Resources, Jiangxi Academy of Sciences, Nanchang 330096, China
| | - Qiuyue Zheng
- Key Laboratory of Biotechnology and Bioresources Utilization of Ministry of Education, College of Life Science, Dalian Minzu University, Dalian 116600, China
| | - Jijuan Cao
- Key Laboratory of Biotechnology and Bioresources Utilization of Ministry of Education, College of Life Science, Dalian Minzu University, Dalian 116600, China
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Önal N, Avşar C, Aras ES. Detection of multidrug-resistant Pseudomonas isolates and distribution of denitrifying functional genes. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2021; 31:1015-1031. [PMID: 31994901 DOI: 10.1080/09603123.2020.1720619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 01/21/2020] [Indexed: 06/10/2023]
Abstract
The aim of this study was to characterize 59 Pseudomonas strains isolated from soil samples in terms of Inducible Beta-Lactamase (IBL), fluorescence production, antibiotic resistance, presence of plasmids and genetic diversity, as well as denitrification functional genes. Fourteen out of fifty-nine (23.7%) Pseudomonas isolates were identified as multidrug-resistant. To evaluate the contribution of denitrification functional genes to genetic diversity, PCR products were screened by RFLP. It was determined that the 18, 6 and 22 out of 59 isolate harbored nirS, nirK and nosZ genes, respectively. It was found that the 37 isolates were nosZ-negative. Thus, these results suggest that nosZ gene-missing pseudomonad denitrifiers are partly contribute to N2O emission. Moreover, nirS, nirK and nosZ genes were found to be positive with IBL and negatively correlated with fluorescence production. These results suggest that Pseudomonas species have important roles in soil and even in biosphere due to their diversity and genetic factors.
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Affiliation(s)
- Nur Önal
- Department of Biology, Faculty of Arts and Sciences, Sinop University, Sinop, Turkey
| | - Cumhur Avşar
- Department of Biology, Faculty of Arts and Sciences, Sinop University, Sinop, Turkey
| | - E Sümer Aras
- Department of Biology, Faculty of Science, Ankara University, Ankara, Turkey
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Harikrishnan R, Devi G, Balasundaram C, Van Doan H, Jaturasitha S, Ringø E, Faggio C. Effect of chrysophanic acid on immune response and immune genes transcriptomic profile in Catla catla against Aeromonas hydrophila. Sci Rep 2021; 11:612. [PMID: 33436677 PMCID: PMC7804155 DOI: 10.1038/s41598-020-79629-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 12/07/2020] [Indexed: 01/29/2023] Open
Abstract
The effect of chrysophanic acid (CA) (2, 4, and 8 mg kg-1) on the immunity and immune-related gene profile of Catla catla against Aeromonas hydrophila is reported. In both control and treated groups fed with 2 mg kg-1 (2 CA), the phagocytosis, hemolytic, myeloperoxidase content, and superoxide anion production decreased significantly between 6th and 8th weeks, whereas when fed with 4 mg kg-1 CA (4 CA) the H2O2 production and nitric oxide synthase increased significantly between 4th and 8th week. When fed with 2 CA and 4 CA diets, the total protein, bactericidal, and antibody titer increased significantly from the 4th week onwards. When fed with 2 CA, the IL-1β and IL-10 mRNA expression of head kidney leucocytes were significant between weeks 6 and 8. The expressions of toll-like receptors significantly increased when fed with a 4 CA diet from 4th week onwards. The 4 CA group significantly increased in TNF-α, TNF receptor-associated factor 6 (NOD), which influences protein expression, after the 4th week. The mRNA transcription of MHCI, lysozyme-chicken and goose type expressions significantly increased in 4 CA group within the 4th week. In summary, the dietary administration of 4 mg kg-1 of CA (4 CA) provides better immunity and enhances the up-regulation of immune-related genes in Catla against A. hydrophila.
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Affiliation(s)
- Ramasamy Harikrishnan
- grid.413015.20000 0004 0505 215XDepartment of Zoology, Pachaiyappa’s College for Men, Kanchipuram, Tamil Nadu 631 501 India
| | - Gunapathy Devi
- grid.411678.d0000 0001 0941 7660Department of Zoology, Nehru Memorial College, Puthanampatti, Tamil Nadu 621 007 India
| | - Chellam Balasundaram
- grid.412909.70000 0001 2287 9472Department of Herbal and Environmental Science, Tamil University, Thanjavur, Tamil Nadu 613 005 India
| | - Hien Van Doan
- grid.7132.70000 0000 9039 7662Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai, 50200 Thailand ,grid.7132.70000 0000 9039 7662Science and Technology Research Institute, Chiang Mai University, 239 Huay Keaw Rd., Suthep, Muang, Chiang Mai, 50200 Thailand
| | - Sanchai Jaturasitha
- grid.7132.70000 0000 9039 7662Department of Animal and Aquatic Sciences, Faculty of Agriculture, Chiang Mai University, Chiang Mai, 50200 Thailand ,grid.7132.70000 0000 9039 7662Science and Technology Research Institute, Chiang Mai University, 239 Huay Keaw Rd., Suthep, Muang, Chiang Mai, 50200 Thailand
| | - Einar Ringø
- grid.10919.300000000122595234Norwegian College of Fishery Science, Faculty of Bioscience, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway
| | - Caterina Faggio
- grid.10438.3e0000 0001 2178 8421Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Piazza Pugliatti, Italy
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Borgia VJF, Thatheyus AJ, Murugesan AG, Alexander SCP, Geetha I. Effects of effluent from electoplating industry on the immune response in the freshwater fish, Cyprinus carpio. FISH & SHELLFISH IMMUNOLOGY 2018; 79:86-92. [PMID: 29738873 DOI: 10.1016/j.fsi.2018.05.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 04/28/2018] [Accepted: 05/04/2018] [Indexed: 06/08/2023]
Abstract
The present study was designed to assess the effect of sublethal concentrations of electoplating industry effluent (EIE) on the non-specific and specific immune responses in the freshwater fish, Cyprinus carpio. Sublethal concentrations of electroplating industry effluent such as 0.004, 0.007, 0.010 and 0.013% were chosen based on the LC50 values. Experimental fish were exposed to these sublethal concentrations of EIE for 28 days. After 7, 14, 21 and 28 days of treatment, non-specific immune response by serum lysozyme activity, myeloperoxidase activity and antiprotease activity and specific immune response by antibody response to Aeromonas hydrophila using bacterial agglutination assay and ELISA were assessed. The results showed that chronic exposure of fish to 0.004, 0.007, 0.010 and 0.013% EIE, dose-dependently decreased the non-specific and specific immune responses on all the days tested compared to control fish whereas statistically significant suppressive effects were observed in fish exposed to 0.013% of EIE on all activities tested.
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Affiliation(s)
- V J Florence Borgia
- PG and Research Centre of Zoology, J. A. College for Women, Periyakulam, Tamil Nadu, India
| | - A J Thatheyus
- PG and Research Department of Zoology, The American College, Madurai, Tamil Nadu, India.
| | - A G Murugesan
- S.P.K.Centre of Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, Tamil Nadu, India
| | | | - I Geetha
- PG and Research Centre of Zoology, J. A. College for Women, Periyakulam, Tamil Nadu, India
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Rajendran P, Subramani PA, Michael D. Polysaccharides from marine macroalga, Padina gymnospora improve the nonspecific and specific immune responses of Cyprinus carpio and protect it from different pathogens. FISH & SHELLFISH IMMUNOLOGY 2016; 58:220-228. [PMID: 27633680 DOI: 10.1016/j.fsi.2016.09.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/27/2016] [Accepted: 09/11/2016] [Indexed: 06/06/2023]
Abstract
Immunostimulation by plant-derived compounds presents a fascinating alternative to vaccines and antibiotics in aquaculture. Fish farmers are longing for immunostimulants that activate both specific and nonspecific immune responses of fish and protect fishes from all possible infections. In this study, we observed that polysaccharide fraction from marine macroalga, Padina gymnospora stimulated the immune response of common carp Cyprinus carpio (Filed for patent, Indian patent no. 201641027311 dated:10-Aug-2016). Our results indicate that fish fed with polysaccharides as feed supplement improved all the immune parameters tested which include serum lysozyme, myeloperoxidase activities and antibody response. Further, polysaccharide fraction protected the fish from its common bacterial pathogens namely Aeromonas hydrophila and Edwardsiella tarda with relative percent survival (RPS) values of 80 and 60 respectively. Gene expression studies, indicate that the immunostimulation by P. gymnospora might be at least in part due to the upregulation of the cytokine interleukin-1β (IL-1β) and antimicrobial peptide lysozyme-C.
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Affiliation(s)
| | - Parasuraman Aiya Subramani
- Centre for Fish Immunology, Vels Institute for Science, Technology and Advanced Studies (VISTAS), Pallavaram, Chennai 600117, India
| | - Dinakaran Michael
- Centre for Fish Immunology, Vels Institute for Science, Technology and Advanced Studies (VISTAS), Pallavaram, Chennai 600117, India.
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7
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Chakrabarti R, Srivastava PK, Verma N, Sharma J. Effect of seeds of Achyranthes aspera on the immune responses and expression of some immune-related genes in carp Catla catla. FISH & SHELLFISH IMMUNOLOGY 2014; 41:64-69. [PMID: 24657259 DOI: 10.1016/j.fsi.2014.03.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 02/26/2014] [Accepted: 03/07/2014] [Indexed: 06/03/2023]
Abstract
Evaluation of functional mechanism of immunostimulant in fish is essential for realizing their therapeutic potential. The impact of dietary supplementation of seeds of Achyranthes aspera on the immune system of Catla catla was studied. Catla (37.73 ± 6.7 g) were fed with test diets containing 0.5 (D1) and 1.0% (D2) seeds of A. aspera and control diet (D3) for 50 days. Then fish were immunized with heat-killed Aeromonas hydrophila. Blood and tissue samples were collected after 7 days of immunization. Three fish were sacrificed for each parameter. Respiratory burst activity, bactericidal activity and antibody response were significantly (P < 0.05) higher in test diets fed catla compared to the control one. Nitric oxide synthase and serum lysozyme were significantly (P < 0.05) higher in fish fed with diet D2 compared to the other treatments. There were up-regulations of TNFα, lysozyme c and g gene expressions in kidney and IL-10, lysozyme c and g expressions in hepatopancreas of test diets fed fish compared to the control one. The expression of IL-10 was down-regulated in the kidney of D2 diet fed fish compared to others. In the gill, significantly (P < 0.05) higher expressions of TNFα was found in D1 diet feed fish and lysozyme c and in D2 diet fed fish compared to the other groups. This study showed tissue-specific gene expression pattern in catla. An inverse relationship was found between the expression of TNFα and IL-10 in kidney of catla.
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Affiliation(s)
- Rina Chakrabarti
- Aqua Research Lab, Department of Zoology, University of Delhi, Delhi 110007, India.
| | | | - Nandini Verma
- Aqua Research Lab, Department of Zoology, University of Delhi, Delhi 110007, India
| | - JaiGopal Sharma
- Department of Biotechnology, Delhi Technological University, Delhi 110042, India
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8
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Longyant S, Chaiyasittrakul K, Rukpratanporn S, Chaivisuthangkura P, Sithigorngul P. Simple and direct detection of Aeromonas hydrophila infection in the goldfish, Carassius auratus (L.), by dot blotting using specific monoclonal antibodies. JOURNAL OF FISH DISEASES 2010; 33:973-984. [PMID: 21091724 DOI: 10.1111/j.1365-2761.2010.01197.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A combination of eight isolates of Aeromonas hydrophila was used to produce monoclonal antibodies (MAbs). Ten different groups of MAbs specific to Aeromonas were selected. The first five groups of MAbs demonstrated high specificity and bound to only one or two isolates of A. hydrophila. The sixth and the seventh groups of MAbs were A. hydrophila specific. They recognized seven of eight A. hydrophila isolates (AH1, 2, 3, 4, 5, 6, 8); however, the MAb in the seventh group also showed cross-reactivity to one isolate of Aeromonas caviae (AC3). The eighth MAb group recognized two isolates of A. hydrophila (AH2 and AH5) and demonstrated cross-reactivity to one isolate of Aeromonas sobria (AS1) and one isolate of A. caviae (AC3). The tenth group of MAbs bound to all isolates of Aeromonas spp. tested (AH1-8, AS1-6, AC1-5, Aeromonas veronii and Aeromonas jandaei) without cross-reactivity to any of the other bacteria tested. MAbs in the ninth group showed similar specificity to those in the tenth group but did not recognize two isolates of A. sobria (AS4 and AS6) or A. jandaei. All the MAbs could be used to identify Aeromonas by dot blotting with a sensitivity ranging from 10⁵ to 10⁷ CFU mL⁻¹. However, the sensitivity of detection was increased to 10²-10³ CFU mL⁻¹ after inoculation of the sample in tryptic soy broth for 3-6 h before performing the dot blotting. The dot blot method can be used for the direct detection of A. hydrophila infection in symptomatic and asymptomatic goldfish. This study demonstrated a convenient immunological tool that can be used for the direct detection of A. hydrophila and Aeromonas infections in a complex sample without the requirement for separation of the bacteria or isolation and biochemical tests.
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Affiliation(s)
- S Longyant
- Department of Biology, Faculty of Science, Srinakharinwirot University, Bangkok, Thailand
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Prabakaran M, Binuramesh C, Steinhagen D, Dinakaran Michael R. Immune response in the tilapia, Oreochromis mossambicus on exposure to tannery effluent. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2007; 68:372-8. [PMID: 17261332 DOI: 10.1016/j.ecoenv.2006.11.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2006] [Revised: 11/02/2006] [Accepted: 11/18/2006] [Indexed: 05/13/2023]
Abstract
The objective of the study was to investigate the effect of chronic exposure to sublethal concentrations of tannery effluent (TE) on the specific immune response and nonspecific immunity in tilapia, Oreochromis mossambicus. The effluent from the tannery was collected directly from a chrome-tanning factory situated in Dindigul district, Tamil Nadu, India. Apart from chromium (88.2 ppm), the effluent contained appreciable amount of calcium carbonate and sodium sulphate. Groups of fish (45-50 g) were exposed to 0.0053, 0.053 or 0.53% [0.1%, 1% or 10% LC50] of TE for 28 days. The specific immune response of fish was assessed by antibody response to heat-killed Aeromonas hydrophila by ELISA and bacterial agglutination assay. Nonspecific immune mechanisms were assessed in terms of serum lysozyme activity, production of intracellular reactive oxygen species (ROS) and reactive nitrogen intermediates (RNI) by peripheral blood leucocytes (PBL). The results indicate that chronic exposure of fish to 0.53% of TE, significantly suppressed antibody response, nonspecific serum lysozyme activity, and ROS and RNI production. Exposure to 0.053% (1% LC50) of TE also caused a similar suppressive effect though at a lesser degree. In conclusion, the study shows, that exposure to sublethal concentrations of TE, can lead to adverse effects on selected immune reactions in tilapia. Further, these findings may be important in terms of monitoring fish health and risk assessment during periods of fluctuating levels of pollutants in the natural and farm environments.
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Affiliation(s)
- M Prabakaran
- Centre for Fish Immunology, Postgraduate and Research, Department of Zoology, Lady Doak College, Madurai-625 002, Tamil Nadu, India
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Binuramesh C, Prabakaran M, Steinhagen D, Michael RD. Effect of sex ratio on the immune system of Oreochromis mossambicus (Peters). Brain Behav Immun 2006; 20:300-8. [PMID: 16256305 DOI: 10.1016/j.bbi.2005.09.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2005] [Revised: 09/09/2005] [Accepted: 09/09/2005] [Indexed: 11/17/2022] Open
Abstract
The social environment of fish has a crucial role to play on the immune system and hence on the overall health status. Stressors of social origin such as dominance, subordination, and fight for mate have a major impact on the immune system of fish. The present study was designed with the objective of finding the effect of sex ratio of the population on the immune system of Oreochromis mossambicus. Groups of fish were maintained for 28 days in three different sex ratios i.e., (i) all-male (ii) all-female (iii) equal male and female (mixed). The specific immune response of fish was assessed by antibody response to Aeromonas hydrophila by ELISA and bacterial agglutination assay, and to SRBC by plaque forming cell assay. Nonspecific immune mechanisms were assessed in terms of serum lysozyme activity, production of intracellular reactive oxygen species (ROS) and reactive nitrogen species (RNS) by peripheral blood leukocytes. Disease resistance against live, virulent A. hydrophila was performed to assess the overall functional immunity. The results showed that antibody responses and numbers of antibody producing cells were increased in fish in the equal male and female sex ratio group compared to fish in monosex ratio groups. Similar enhancement was also observed in nonspecific serum lysozyme level and the ROS and RNS production. The host resistance test revealed that enhanced immunity in equal male and female sex ratio group was protective against A. hydrophila infection. The study clearly reveals positive and negative effect of sex ratio on the immune system of O. mossambicus.
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Affiliation(s)
- C Binuramesh
- Centre for Fish Immunology, P.G. and Research Department of Zoology, Lady Doak College, Madurai 625002, Tamilnadu, India
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