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ThesisItem Restricted STUDIES ON NON TUBERCULOUSMYCOBACTERIUM IN LIVESTOCK AND FARMENVIRONMENT(2021) SANGAVIM C; TANUVAS; PORTEEN K; SURESHKANNAN S; AMUEL MASILAMONI RONALD BThe aim of the study was to determine the occurrence of Non TuberculousMycobacteriainlivestockandfarm environment(organizedandunorganizedfarms) in and around Chennai, Tamil Nadu and to investigate the presence ofantimycobacterialresistancepatternagainst theisolatesobtainedinthestudy. A total of 218 samples, including 50 water samples, 55 milk samples, 50 soilsamples, 50 dung samples and 13 sewage samples were collected from multiplefarmpremisesin andaround Chennai andthesamplesweresubjected to isolation and identification of NTM species by conventional and molecular methods. Allthe samples were subjected todecontamination protocols using oxalic acid-NaOH and CPC. Sediments from the decontaminated samples were screenedinitially by Acid Fast Staining and the samples showing Acid Fast Bacilli were cultured in liquid mediaviz.Herrold’s eggyolk broth and Middlebrook 7H9 broth. The samplesfrom liquidmedia were streaked on MB 7H10 agar andincubated. The presumptive isolates were subjected to various biochemical testslike growth on McConkey agar, growth in 5% NaCl, catalase test, iron re-uptakemechanism from the medium and T2CH test. Further confirmation of the isolateswere done by PCR assay targeting 16SrRNA and hsp 65 genes and then the PCR products were subjected to sequencing.The isolates confirmed as NTM by genotypic characterization was subjected to AMR studies by broth microdilution method against first line antimyco bacterial drugs like rifampicin, isoniazid, ethambutol and pyrazinamide with varying concentrations starting from 100μg to 0.0048μg. The isolates were then tested for AMR by disc diffusion method using azithromycin, rifampicin, enrofloxacin, ciprofloxacin, imipenam, amikacin, doxycycline and cotrimaxazole and the sensitivity and resistance pattern were recorded.ThesisItem Restricted ASSESSMENT OF MATERNAL DERIVED ANTIBODY AND HUMORAL IMMUNE RESPONSE IN PUPS AGAINST CANINE DISTEMPER VACCINES(2021) BHAMBHANI MITALI INDER; TANUVAS; ASOKKUMAR M; RAMESH A; SENTHIL NRCanine distemper (CD) is a highly contagious and fatal viral disease of canines, which was recognized as one of the leading causes of dog mortality next to rabies. CDV most commonly infect the puppies when the maternally derived antibodies are below the threshold level. Immunization is a major weapon in the effective control of many viral diseases of pet animals and it is generally carried out against canine distemper in pups either by using bivalent (DP) or multivalent (DHPPi+L) vaccine, but there is not much data available about the dynamics of antibody level in naive pups and immunized animals in tropical countries like India. Although the vaccination against canine distemper is in regular practice, the incidence of the disease is more commonly noticed which may be due to lack of long-standing population immunity, exposure to high virus bio burden or improper sero-conversion of antigen presented. The persistence of canine distemper is as a result of insufficient vaccinations in cases where multiple vaccinations are a common practice and/or vaccination failure probably due to faulty vaccine and interference by maternally derived antibody (MDA). The probable cause of vaccination failure could be the maternally derived antibody or passively acquired antibodies at the time of vaccination with other factors being delay in the maturation of immune system or organs, genetic inability to respond to certain vaccine antigens, ineffective vaccination, immune-suppression duo to other disease conditions or physiological stress as well as poor vaccine immunogenicity and improper maintenance of cold chain at the time of transportation of the vaccines.ThesisItem Restricted PATHOTYPING AND ANTIMICROBIAL RESISTANCE PATTERN OF Escherichia coli ISOLATES FROM RAW MILK AND DAIRY ENVIRONMENT(2022) SENTHIL KUMAR A; TANUVAS; SURESHKANNAN S; PORTEEN K; PUGAZHENTHI TREscherichia coli is an common food pathogen with widespread distribution. Hence, the present study has been contemplated to ascertain the presence of E.coli in bovine milk and dairy farm environmental interface and to determine the pathotype by molecular assay. Further, antibiotic resistance patterns of the E.coli isolates were determined by both phenotypic and genotypic methods. A total of 230 samples comprising of 116 milk, 54 dung, 30 swab from dairy equipments, 15 water and 15 air samples were collected from both organised and unorganised bovine farms in and around Chennai City, Tamil Nadu, India were screened for the presence of E.coli by conventional method viz., cultural and biochemical tests and the presumptive colonies were further confirmed by PCR targeting uspA gene. The distribution of positive isolates obtained from various samples viz. raw milk samples (25/116), dung (15/54), water (8/15), air (4/15) and swab (3/30) with overall occurrence of E.coli in the present study was 23.91 percent (55/230). All the presumptive isolates were biochemically characterized and were subjected to PCR assay. Results of our study have clearly indicated 100 percent correlation between biochemical test and PCR assay.ThesisItem Restricted SEAFOOD HYGIENE AND SAFETY - STATUS AND EFFECTIVENESS OF QUALITY MANAGEMENT(2021) ANNIE SUPRIYA R; TANUVAS; SURESHKANNAN S; SAMUEL MASILAMONI RONALD; TIRUMURUGAAN KG; PORTEEN K; UMA AA polluted marine environment may end in food chain and pose risk to public health. Fish and fishery products are at the forefront of food safety and quality improvement because they are among the most traded food commodities. The present study was designed to screen the seafood samples for the levels of sanitary and safety indicators, to study the presence of bacterial sea food pathogens of zoonotic importance by conventional and molecular methods and their antibiotic resistance pattern by phenotypic methods, to estimate the level of heavy metal concentrations from the sea food samples and to assess the compliance with food hygiene requirements by comparing with the prescribed standards by ICMSF and FSSAI. Assorted sea food samples which includes fishes, prawns, crabs and squids were collected from three major landing centers of Chennai, Royapuram Pattinapakkam and Ennore. A total number of 433 samples were collected which include 138 prawns, 145 fishes, 90 crabs and 60 squids, and a total number of 190 seafood samples from Royapuram, 153 from Pattinapakkam and 90 from Ennore landing centres. The levels of sanitary indicators viz. aerobic plate count, yeast and mould count and coagulase positive Staphylococcus aureus count were studied.The Aerobic plate count from the landing centres ranged from 1.0x106 to 5x107CFU per gram. The maximum range of aerobic plate count was observed in crabs (1.0 x106 to 5.0x107 CFU per gram) from Royapuram. The Yeast and mould from all the three landing centres ranged from 1.0x101 to 5x103 CFU per gram. The maximum levels reported in crabs (1.0 x 101 to 5.0 x103 CFU per gram) from Royapuram. The number of coagulase positive Staphylococcus aureus ranged between 1x101 to 1x102 CFU per gram. Highest count (1x102 CFU per gram) observed in fishes from Royapuram. The sanitary indicators observed in all the three landing centres were in the prescribed limits of FSSAI and ICMSF, except for crabs and squids. A very high Significance observed for the interaction between sanitary indicators and seafoods (P<0.001). Significant difference (<0.05) observed for the interaction between sampling site and seafood.ThesisItem Restricted CHARACTERIZATION AND EVALUATION OF BIOCONTROL AGENTS TO COMBAT Listeria monocytogenes IN FOODS OF ANIMAL ORIGIN(2021) CHINTA SIVA SWETHA; TANUVAS; PORTEEN K; ELANGO A; SAMUEL MASILAMONI RONALD B; SENTHIL KUMAR TMAListeria monocytogenes is an emerging zoonotic pathogen with widespread distribution, the present study has been contemplated to ascertain the presence of L.monocytogenes in foods of animal origin, environmental interface and to determine the serotype, virulence by molecular assay and genotypic characterization of the isolates. Further, antibiotic resistance patterns of the isolates were determined by both phenotypic and genotypic methods and selected essential oils of plant origin were tested for the antimicrobial activity against L.monocytogenes isolates. A total of 474 samples comprising of 274 milk, fifty of each soil, feed, sewage and beef samples were collected from different bovine farms and slaughter house in and around Chennai City, Tamil Nadu, India were screened for the presence of L.monocytogenes by conventional method viz., cultural and biochemical tests and the presumptive colonies were further confirmed by PCR targeting hlyA gene. The overall occurrence of L.monocytogenes in the present study was 2.1 percent (10/474) with high occurrence rate in raw milk samples (8/274), followed by soil (1/50) and beef samples (1/50) while none of the feed and sewage sample were positive for L.monocytogenes by PCR. Serotyping and lineage studies have shown that all the ten confirmed L. monocytogenes isolates were belonging to a single serogroup viz., 1/2a, 3a serogroup (100%) and falls under type II lineage (L2) viz., 1/2a, 1/2c, 3a, 3c serotypes (100%) by multiplex PCR. Further, all the ten L.monocytogenes were studied for various virulence genes and found that iap gene was present in all ten isolates (100%), while plcA and plcB genes were observed in seven (70%) and eight (80%) isolates respectively.ThesisItem Restricted ISOLATION AND CHARACTERIZATION OF ANTIMICROBIAL RESISTANT CAMPYLOBACTER SPP. FROM CHICKEN MEAT SOLD IN DIFFERENT ZONES OF CHENNAI(2018) Anusha, SA; Gunaseelan, L; Appa Rao, V; Porteen, K; TANUVASA study comprising of three parts was conducted, firstly, to assess the contamination of thermophilic Campylobacter spp. in retail chicken meat sold in Chennai Corporation limits, secondly, to determine the antimicrobial resistance pattern of the obtained Campylobacter spp. isolates by using the phenotypic method of Kirby- Bauer disc diffusion and genotypic characterization for antimicrobial resistance genes using Polymerase Chain Reaction. The third part consisted of assessing the biofilm forming ability by Congo red agar assay and micro titer plate assay. For the first part of the study, samples collected randomly from all fifteen zones of Chennai Corporation were screened for the presence of Campylobacter spp. by conventional culture method and further confirmed by Polymerase Chain Reaction. After confirmation of the Campylobacter genus, the isolates were identified to the species level by using species specific primers and also by multiplex PCR. The results of prevalence study showed that 66.67 percent (218/327) of the chicken meat portions examined were showing presumptive colonies for Campylobacter spp. Molecular identification revealed that 25.38 percent (83/327) of the total samples were positive. Breast meat portions showed high levels of contamination in both assays.In the second experiment, a representative portion of isolates consisting of Campylobacter jejuni, Campylobacter coli and mixed isolates containing Campylobacter jejuni and Campylobacter coli were assessed for resistance pattern against ciprofloxacin, tetracycline, cefoxitin, tylosin and colistin among which ciprofloxacin, tetracycline and cefoxitin resistance was observed. The presence of various antimicrobial resistance genes corresponding to fluroquinolones, betalactams, tetracyclines and erythromycin resistance were identified. The third part of the study revealed that the isolates obtained from this region were potent biofilm formers showing black discoloration on Congo red agar. Hence the complete study demonstrates the presence of antimicrobial resistant and biofilm forming ability of Campylobacter spp. which poses a major zoonotic threat to the public health in contaminated chicken meat portions.ThesisItem Restricted DETERMINATION OF ANTIMICROBIAL RESISTANCE PATTERN OF MAJOR BACTERIAL PATHOGENS OF PUBLIC HEALTH SIGNIFICANCE(2018) Josy, Anjana; Gunaseelan, L; Porteen, K; Sriram, P; TANUVASThere is increasing concern about the rapid emergence and spread of antibiotic resistant bacteria and antimicrobial resistance has been considered as the most vital health issue of 21st century by WHO. The close contact between animals and people offers favourable conditions for bacterial transmission and this initial study attempts to isolate selected pathogens of common interest in man and animals from hand swabs and nasal swabs of animal handlers, viz., Staphylococcus spp., Streptococcus spp., Klebsiella spp. and Pseudomonas spp. and to determine their antimicrobial resistance pattern both phenotypically and genotypically.ThesisItem Open Access SPATIAL AND TEMPORAL DISTRIBUTION OF JAPANESE ENCEPHALITIS INFECTION WITH SPECIAL REFERENCE TO ANIMAL ASSOCIATION AND POTENTIAL HAZARD TO HUMAN HEALTH(TANUVAS, 2016) Sonuwara, Begum; Sekar, M; Gunaseelan, L; Kumanan, K; TANUVASJapanese encephalitis virus (IEV) is a mosquito borne flavivirus and is a significant zoonotic pathogen. Geographically it is present in most of the Asian countries and some Pacific areas. The main vector of JEV is mosquitoes belonging to the genus Culex. Birds and pig function as host and virus amplifiers, whereas humans are accidental hostsThesisItem Open Access CHARACTERIZATION OF EXTENDED SPECTRUM ß-LACTAMASE PRODUCING ESCHERICHIA COLI AND SALMONELLA IN FOODS OF ANIMAL ORIGIN(TANUVAS, Chennai, 2017) Kumar, Radhika Ratheesh; Porteen, K.; TANUVAS; Selvaraju, G.; Ramesh, S.The present study was designed to characterize Extended-Spectrum β-Lactamase (ESBL) producing Escherichia coli and Salmonella from foods of animal origin. A total of 300 samples, 100 each of meat (56 chicken, 44 mutton), milk (60 raw, 40 pasteurized) and milk products (20 each of curd, ghee, payasam, rasgulla and gulab jamun) were collected in and around Chennai. All the samples collected were subjected to isolation of E.coli and Salmonella by standard conventional and molecular methods.
