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Anand Agricultural University, Anand
Anand Agricultural University (AAU) was established in 2004 at Anand with the support of the Government of Gujarat, Act No.(Guj 5 of 2004) dated April 29, 2004. Caved out of the erstwhile Gujarat Agricultural University (GAU), the dream institution of Sardar Vallabhbhai Patel and Dr. K. M. Munshi, the AAU was set up to provide support to the farming community in three facets namely education, research and extension activities in Agriculture, Horticulture Engineering, product Processing and Home Science. At present there seven Colleges, seventeen Research Centers and six Extension Education Institute working in nine districts of Gujarat namely Ahmedabad, Anand, Dahod, Kheda, Panchmahal, Vadodara, Mahisagar, Botad and Chhotaudepur
AAU's activities have expanded to span newer commodity sectors such as soil health card, bio-diesel, medicinal plants apart from the mandatory ones like rice, maize, tobacco, vegetable crops, fruit crops, forage crops, animal breeding, nutrition and dairy products etc. the core of AAU's operating philosophy however, continues to create the partnership between the rural people and committed academic as the basic for sustainable rural development. In pursuing its various programmes AAU's overall mission is to promote sustainable growth and economic independence in rural society. AAU aims to do this through education, research and extension education. Thus, AAU works towards the empowerment of the farmers.
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ThesisItem Open Access CHARACTERIZATION OF DETERMINANT FOR TRANSFERABLE ANTIMICROBIAL DRUG RESISTANCE AND VIRULENCE ASSOCIATED FACTORS OF S. GALLINARUM(AAU, Anand, 1999) Patel, Ashvinkumar Ramabhai; Roy, A.In the present study characterization of antimicrobial drug resistance and its transferable nature in S. gallinarum isolates was carried out. Further curing of R-determinants and the effect of curing on virulence on virulence associated factros viz., colicinogeny and serum resistance was ascertained. Virulence of isolates were assayed by lethality and invasiveness assay and attempts were also made to isolate plasmid from S. gallinarum isolates. In vitro antimicrobial drug resistance against 10 commonly used antibiotics were detected. All the S. gallinarum isolates showed resistance against one or more drug tested. All the isolates were resistant to sulfamethoxazole while higher number of isolates showed resistance to nalidixic acid, gentamicin and enrofloxacin. Moderate number of isolates showed resistance against furazolidone, streptomycin, tetracycline and cotrimoxazole while resistance against pefloxacin was shown by lesser number of isolates. Least resistance isolates were observed for chloramphenicol. In vitro transfer of drug resistance was also studied. Out of 12 S. gallinarum isolates tested all (100 per cent) were found to transfer resistance against tetracycline, nine (75 per cent) isolates transferred en bloc resistance against tetracycline, gentamicin and sulfamethoxazole while three (25 per cent) isolates transferred resistance against only tetracyc1ine. In vivo transfer of drug resistance was carried out from two donor strains of S. gallinarum to recipient E. coli strain. Out of two S. gallinarum strains tested both revealed transfer of drug resistance from donor to recipient. Total 20 (57.1 per cent) isolates out of 35 isolates tested were found to produce bacteriocin. Twelve isolates were tested for transfer of colicinogeny, out of which six (56 per cent) were able to transfer of colicinogeny to recipient E. coli strain along with multiple drug resistance. Elimination of drug resistance (curing) markers in six strains of S. gallinarum were studied using different chemical and physical method. The chemical agents used for curing were ethidium bromide (EtBr) and novobiocin (Novo) ethidium bromide and novobiocin combination and sodium dodecyl sulfate (SDS). In present study the elimination of drug resistance by chemical agents observed frequently. Use of EtBr and SDS resulted in curing of drug resistance in all six strains while five and four strains were cured by EtBr and Novo combination and novobiocin alone respectively. In physical method of curing, 3 out of six S. gallinarum strains were eliminated drug resistance on 1 day of incubation at 45°C and higher number of curing frequencies, was observed on subsequent days. Thus resistance markers were more readily eliminated by incubation at 45°C for prolonged periods of time rather than by chemical agents. Resistance of six strains of S. gallinarum wild and their cured derivatives to bactericidal effect of chicken serum was studied. The study revealed that all the wild and cured strains tested were resistant to chicken serum. To know the role of virulence associated factors like colicinogeny and serum resistance, virulence assay of six selected wild and their cured derivatives was carried out by determining their lethality as well as invasiveness ability in day old chicks. In lethality assay wild strains (S-21, S-4 and S-27) caused mortality 66.66, 60.00 and 46.66 per cent respectively, while their cured derivatives caused mortality of 46.66, 20.00 and 20.00 per cent respectively. At the 15th day post infection (PI) surviving birds revealed infection as per the CFU count method. In invasiveness assay there was no significant difference in the CFU count among S. gallinarum wild. isolates and their cured derivatives was observed upto 12 day CFU count, but by the 16th day none of the chicks survived in wild strains. Thus it indicates that wild strains were more invasive and lethal as compared to their cured derivatives. All the surviving birds in cured group revealed infection at 16th PI. There was no apparent difference found between lesions of wild and the cured derivatives during virulence assay. Isolation of plasmids from 10 wild and their eight cured derivatives of S. gallinarum were carried out. Majority of the strains showed a plasmid of molecular weight 56 Md. In addition other small plasmids found were of 2.8 Md and 1.79 Md molecular weight.ThesisItem Open Access SEROPREVALENCE AND DIAGNOSIS OF BLUETONGUE VIRUS BY REVERSE TRANSCRIPTASE POLYMERASE CHAIN REACTION(AAU, Anand, 1998) Hinsu, T. V.; Kher, H. N.Bluetongue (BT) is an insect transmitted viral disease of several species of domestic and wild ruminants. The disease is a cause for serious concern to livestock industry due to staggering direct and indirect economic losses. In many countries like India having considerable sheep population, the disease has become endemic. Severity of the infection depends upon the species and breed of animals, serotypes/strains of the virus and prevalent ecosystem. The present study was aimed to find out prevalence of Bluetongue virus (BTV) antibodies in domestic ruminants and of Epizootic haemorrhagic disease virus (EHDV) antibodies in cattle of Kutch district of Gujarat state. Agar gel immunodiffusion (AGIO) and competitive enzyme-linked immunosorbent assay (c-ELISA) employed for antibody detection were also compared in terms of their sensitivity and specificity. An attempt was also made to standardize Reverse transcriptase-polymerase chain reaction (RT-PCR) for detecting BTV nucleic acid. Out of 162 sera tested, 87 (53.70%) and 126 (77.78%) were found to be positive for BTV antibodies by AGID and c-ELISA respectively. Specieswise, 24.56 and 63.16% of sheep, 80.00 and 96.36% of goats and 58.00 and 74.00% of cattle revealed antibodies to BTV by AGIO and c-ELISA respectively. The highest prevalence rate was found in Northern-east region (70.69 and 86.21%), followed by Central (48.72 and 75.64%) and Southern-west region (30.77 and 65.38%) of the Kutch district, respectively by AGID and c-ELISA. Female animals (63.03 and 86.81%) showed more prevalence than male animals (36.63 and 66.20%), as determined by AGID and c-ELISA respectively. In sheep, higher prevalence rate in native Patanwadi breed (47.06 and 86.16%) was observed than the crossbreds (11.76 and 43.48%) by AGID and c-ELISA respectively. A total of 50 cattle sera tested for BTV antibodies were also tested for EHDV antibodies by EHDV-AGID test. Of these, 9 (18.00%) were found positive for EHDV antibodies. Amongst these positive sera, five reacted specifically to EHDV antigen, without crossreacting to BTV antigen. Comparison of c-ELISA and AGID tests for the detection of BTV antibodies, revealed that the former test was better in terms of sensitivity and specificity. Of the total 162 serum samples, 87 and 126 samples reacted positively in AGIO and c-ELISA respectively. Eighty six samples were found positive and 35 negative by both the tests; while 40 samples detected positive by c-ELISA were negative by AGIO. Only one sample reacted positively to AGIO but negative in c-ELISA. This sample turned out to be positive for EHDV antibodies. Relative sensitivity and specificity of AGIO to c-ELISA were 68.25 and 97.22% respectively and overall agreement between both the tests was 74.69%. RT-PCR was employed for detecting BTV nucleic acid using BTV groupspecific segment 7 prime and BHK-21 cells adopted BTV serotype 1. This was attempted essentially to standardize this highly sensitive technique, so as to use it routinely in future for the field samples. The study revealed an amplified product of 500 bp specific to the primer used in the study.ThesisItem Open Access ANTIGENIC CHARACTERIZATION OF EGG DROP SYNDROME-1976 (EDS-76) VIRUS(AAU, Anand, 1994) Bhalja, S. R.; Anjaria, J. M.Egg drop syndrome-1976 (EDS-76) virus has gained importance as one of the major causes of drop in egg production. EDS-78 virus has representative strains like 127 and BC14 which are identical serologically. The possibility of appearance of new isolates can not be ruled out by investigating the variations in immunogenic fractions and their interrelationship say provide indications to select a particular strain for vaccine production and to correlate specific antigenic fractions to immunogenicity of the virus isolate. The present work was on establishing antigenic relationship between strain 127 and two local isolates Sb and Kr of BDS-76 virus employing Haemagglutination inhibition (HI), Agar gel inmunodiffusion (AGID), Counter immunoelectrophoresis (CIEP) and Cross immunoeleotrophoresis (CrIEP). No much significant variation could be observed in the HI titres of sera against strain 127 and isolates Sb and Kr. Thus isolates of EDS-76 were indistinguishable based on HI test. Two common sharing lines were observed in strain 127 and Kr isolate, while one common sharing line was observed in Sb isolate with homologous as well as heterologous system in AGID. More number of precipitation lines were detected in ClEP than that in AGID in homologous and heterologous systens. Closed antigenic relationship was observed among strain 127 and isolates Sb and Kr. In standardized CrIEP using homologous and heterologous system of strain 127 and isolates Sb and Kr, four immuno precipitates were observed in each case. No apparent differences could be established among three isolates (strain 127 and isolates Sb and Kr of EDS-76 virus) by HI test, AGID, CIEP and CrIEP.ThesisItem Open Access SEROPREVALENCE, ANTIGEN DETECTION, EXPERIMENTAL INDUCTION AND ELECTRONMICROSCOPY OF CANINE PARVOVIRUS(AAU, Anand, 1994) Shukla, Devendrakumar V.; KHER, H. N.In veterinary field, dog practice has gained an important position, particularly due to the constant association of man with dog. Canine parvovirus (CPV) infection has emerged as a new disease entity clinically characterized by servere vomition and diarrhoea. The present study on CPV was aimed at screening dog population in and around Anand and Baroda region for prevalence of antibodies against CPV, detection of viral antigen in clinical cases, pathological study in experimental pups, an attempt for isolation and propagation of virus in cell-culture and demonstration of CPV under electronmicroscope (EM).ThesisItem Open Access SEROPREVALENCE, EXPERIMENTAL INDUCTION AND DETECTION OF EGG DROP SYNDROME 1976 VIRUS(AAU, Anand, 1993) Rangnekar, Alpana G.; Kher, H. N.During the last decade, Egg Drop Syndrome has gained importance as one of the major causes of drop in egg production. The present study was aimed at screening of poultry population in and around Anand for the prevalence of antibodies against Egg Drop Syndrome-1976 (EDS-76) virus, detection of virus from clinical cases and its effect on the laying hens and on chicken embryos. Out of the 310 samples screened, 212 samples (68.38 per cent) were found to contain the antibodies against EDS-76 virus by haeraagglutination-inhibition (HI) test. Only one farm was found to be sero-negative, though it had a complaint of drop in egg production. Of the 10 pooled faecal samples collected from the farms, 2 samples were found positive for EDS virus as ascertained by haemagglutination (HA) and haemagglutination-inhibition (HI) tests. Maximum seroprevalence (81.25 per cent) was recorded in the age group of 46-55 weeks, followed by the age group of 36-45 weeks (78 per cent). Forty per cent seroprevalence was detected in the age group of 25-35 weeks. It was possible to produce experimental infection in the 36 week old layers by the EDS virus 127 and the two field isolates (designated as Sb and Kr). Drop in egg production and egg abnormalities were evident. The antibody levels in the serum and egg yolk for each group were high at 21 days PI though the egg yolk antibody levels were slightly lagging behind the serum antibody levels by this time. The histopathological changes were most characteristic and restricted to the pouch shell gland areas of the uterus. In the chicken embryos, severe congestion with mild to moderate haemorrhages in the liver, kidneys and spleen were observed. HA activity was shown by the harvested allantoic fluids.ThesisItem Open Access ASSESSMENT OF IMMUNE RESPONSE TO HAEMORRHAGIC SEPTICAEMIA ALUM PRECIPITATED VACCINE IN CALVES(AAU, Anand, 1993) Lakhtaria, P. T.; Kher, H. N.Studies on immune response to haemorrhagic septicaemia alum precipitated vaccine in cow calves was undertaken at the Department of Veterinary Microbiology, College of Veterinary Science and Animal Husbandry, Anand. Twenty four unvaccinated healthy cow calves of either sex between the age group of four and eight months of Livestock Research Station and Animal Nutrition Department, Veterinary College, Anand were randomly divided into four groups viz., groups I, II, III and IV, each group having six calves. The calves of groups I, II and III were vaccinated with 5 ml of haemorrhagic septicaemia alum precipitated vaccine subcutaneously once, twice and thrice, respectively. Interval between two vaccinations for groups II and III was seven days. The calves of group IV were vaccinated with 5 ml of HS alum precipitated vaccine with simultaneous treatment of levamisole hydrochloride at dose rate of 2.5 mg per kg body weight intramuscularly. The calves of each group were bled prior to the first vaccination and thereafter at monthly interval upto six months. The sera were subjected to IHA test, CFT and PMPT for assessment of immune response. In the sera of calves of group I, overall duration of immunity toy single vaccination was observed upto six months, with variations in peak levels as ascertained by different tests employed. Maximum level of mean IHA antibody titres was at months three and five with no significant difference from that at other months including pr«-vaccination stage. Maximum level of mean CP antibody titres was at month four with no significant difference from that at months two, three, five and six, but it differed significantly from that at month one and pre-vaccination stage. Maximum survivability of mice was observed at months one, two and four. No significant difference in IHA antibody titres was observed in sera of calves of groups II and III in comparison to group I Group mean CF antibody titres of groups I and II did not differ significantly, but the group mean CF antibody titres of group III were significantly higher than those of groups I and II. No significant difference between the survivability rate of mice of groups I, II and III was observed in PMPT. These results indicated that twice vaccination failed to increase immune response, but thrice vaccination had increased the CF antibody titre with no effect on IHA antibody and mouse protecting antibodies. In the sera of calves of group IV, levamisole treatment increased mean CF antibody titres significantly, but failed to increase IHA antibody titres and passive mouse protecting antibody in comparison to calves of group I. While comparing efficacy of different tests, it was observed that IHA titres increased significantly at month two and reached to its peak during months three to five except for drop at month four and fell back at month six close to the level of month two titre. These mean differences were statistically highly significant. No definite conclusion could be made regarding IHA titre. The mean CF titre value increased significantly at month one in relation to pre-vaccination titre. The peak level of mean CF antibody titres were'observed at months two, three and four followed by significant decline at month five and further significant decline at month six. The mean CF values observed during different intervals of post-vaccination period were significantly higher than that at pre-vaccination stage. The results of PMPT indicated that mean value for survivability rate in mice at different months of post-vaccination period were significantly higher than that at pre-vaccination stage. The values were found highest at months one and two followed by gradual decrease during months three, four, five and six.ThesisItem Open Access ANTIGEN DETECTION, PATHOGENICITY AND PERSISTENCE OF MATERNAL ANTIBODIES OF INFECTIOUS BURSAL DISEASE VIRUS(AAU, Anand, 1995) Abraham, Reena; Kher, H. N.Infectious bursal disease is an acute or more commonly a subclinical viral disease of young chickens characterized by lymphocidal effects in the lymphoid organs, especially in the bursa of Fabricius. The disease is known to cause immunosuppression, vaccinal failure and surfacing of latent and subclinical concurrent infection in the infected bird. Present study was aimed at the antigen detection, pathogenicity and persistence of maternal antibodies of infectious bursal disease virus (IBDV). The bursa samples were collected from the dead or ailing birds with specific IBD lesions routinely obtained at the Department of Pathology and were tested for the presence of the viral antigen using agar gel diffusion test (AGDT). The samples obtained from Anand, Karamsad, and Undach gave positive line oi precipitation with known positive serum. The isolates designated as AND (Anand), KAM (Karamsad) and UND (Undach) on the basis of the area from where these samples were obtained, were compared with a reference isolate BAN (Bangalore) for the pathogenicity study. Clinical symptoms were observed in one or two birds -from each group followed by death. Rest of the birds were normal till the end of the observation period . The bursa of Fabricius was found enlarged on the third day PI with gradual atrophy setting in from seventh day PI in all the infected groups. Spleen showed slight enlargement on seventh day PI. Thymus was found to be enlarged on 11th and 14th day PI. The bursa to body weight indices showed significant difference at different intervals. The indices showed that the bursa to body weight ratio in all the infected groups was about two times as compared to that of control on third day PI and from fifth day PI, there was a decrease in this ratio in all the infected group till the end of the observation period suggesting atrophy, The histopathological lesions were mainly seen in bursa of Fabricius (BF) in the form of marked inter and intrafollicular oedema and mild to moderate depletion of lymphoid cells on the third day PI. Mild increase in the interfollicular connective tissue proliferation along with heterophilic infiltration was also seen. The changes became severe on fifth day PI. On seventh day PI, the bursal follicles were atrophied with severe depletion of the lymphocytes in cortex and medulla. On 11th and 14th day PI, large cystic follicles with mononuclear cell infiltration into the interfol1icular area were observed. The spleen lesions were in the form of mild depletion of lymphoid cells along with focal areas of coagulative necrosis and reticulo-endothelial (RE) cell hyperplasia. The thymus and caecal tonsils revealed same type of lesions as spleen. The kidney revealed acute renal congestion and presence of lymphoid foci. The lesions were very mild in the AND and KAM groups of birds. The antigen was detectable in UND group on third day PI and BAN group on third and seventh day PI by AGDT. Using quantitative AGDT, serum antibodies were detected from seventh day PI onwards in the local isolate infected groups and from fifth day PI in the reference isolate infected group. 'The antibody titres showed gradual increase in all groups till the end of the observation'period. For immunosuppressive study, each infected group was vaccinated with sheep erythrocytes and subsequently at weekly interval birds from each group were screened for presence of antibody using HA test. Overall antibody level of control group was significantly higher (P < 0.01) from treatment means of infected group. Among BAN, KAM and AND isolates infected groups, mean HA titres did not show significant difference, but in UND isolate infected group the mean titre was significantly higher than other groups. Further, the infected birds were vaccinated with 'F' vaccine of NDV and each group was screened at weekly interval for presence of antibody using HI test. The HI titres of all the infected groups were significantly lower than that of control group at second and third week suggesting immunosuppressive effect of these isolates. The titres in AND and KAM groups were significantly lower than that in UND and BAN groups during this period indicating their more immunosuppressive effect. Only the UND isolate was adapted to the chick embryos producing mortality in four out of six chick embryos when inoculated via CAM route at fourth passage level. The embryoij were stunted with cutaneous haemorrhages in the cerebral area and on the toes. The other isolates did not adapt to embryos evenafter four passages. The maternal antibodies were found to persist in the chicks hatched from vaccinated parental flock upto 20 days of age as ascertained by ELIBA and quantitative AGDT. The maternal antibodies with the quantitative AGDT titre 1:8 and ELISA titre +3, were found to be protective only upto 15 days of age in chicks against IBDV infection.ThesisItem Open Access GENOMIC PROFILE, ELECTRON MICROSCOPY AND ISOLATION OF BOVINE ROTA VIRUS FROM DIARRHOEIC CALVES(AAU, Anand, 1992) Gandhi, Sandip S.; Kher, H. N.The present study was undertaken in order to screen the faecal samples from diarrhoeic calves and to compare with known rota virus isolates with respect to genetic difference and relative sensitivity of the tests viz., PAGE, Rotalex latex agglutination tests and EM. Faecal samples of 35 diarrhoeic calves were first examined by PAGE. Of these, only one sample from ten-day-old cow-calf was found positive for rota virus by PAGE, Rotalex' latex agglutination test and PAGE were found equally sensitive in detection of rota virus from faecal samples of diarriipeic calves. In the EM study, typical shape of rota virus was observed. The size of individual virus particles was 62 nm. Virus was successfully isolated in MDBK cell - line and produced demonstrable changes after two blind passages. Typical CPE characterized by extensive vacuolation, roundening of the cells and detachment of the cells from the glass surface was observed in MDBK cell-line . The stained coverslips cultures examined at regular intervals showed small vacuolations, crescent shaped and spindle shaped cells. Some of the infected cells exhibited intracytoplasmic inclusion bodies. Crystalline trypsin was used for treating the faecal sample and in the maintenance medium for better recovery of virus. In the electropherogram study of tissue culture adapted isolates of rota virus, it was observed that Indian isolates resembled to UK strain.ThesisItem Open Access ISOLATION, CHARACTERIZATION AND PATHOGENICITY OF SALMONELLA OF POULTRY ORIGIN(AAU, Anand, 1998) Shah, Devendra Hansraj; Roy, A.A present study was undertaken with the view to isolate and characterize salmonella of poultry origin with regard to cultural diaracteristics, biodiemical behaviour, antibiotic resistance pattern, coliduogeny, senun resistance along with the transferability of some of these characters and virulence (pathogenicity) of isolates. All the samples were processed for detection of sahnonella, their cultural and biochemical characters, hi all ninety two sahnonella isolates could be obtained fiom 193 samples from various sources. All the 92 isolates showed Typical pale (non-lactose fermenting) colonies on MCA and red colonies on BGA Ct)mparative efficacy of different culture media used for isolation of salmonella was assessed. Out of 92 salmonella isolates, 89 (%.73 per cent) were isolated upon direct plating either on MCA and/'or BGA. Of these, 51 (55.43 percent) were isolated on bothMCA and BGA, 23 (25 per cent) were isolated only on MCA while 15 (16.30 per cent) were isolated only on BGA. Attempts were also made to use enrichment medium (TTB) for isolation of salmonella and only three (3.27 per cent) isolates out of 92 could be isolated on BGA and MCA after eurichnieut in TTB. Biochemically all the 92 isolates revealed positive for M.R. test, nitrate test, fermentation of sugars viz., duldtol, maltose, dextrin and glucose without gas production. The isolates were negative for indole production, V.P. test, motility test, dtrate utilization, utilization of D-tartrate and fermentation of sugars viz., salidn, adonitol and sorbitol. Twenty ax isolates produced H2S in TSI, 37 isolates revealed ornithine decaiboxylation activity and 10 isolates could not ferment ihamnose. All the 92 isolates were subjected to serotyping and were typed as Salmonella gallinarum (1, 9, 12; - ; - ). In vitro antibiotic resistance pattern against 10 commonly used antibiotics were detected. All the 21 gall'manim isolates showed resistance against one or more drugs tested. All the isolates were resistant to sulfamethoxazole while higher number of isolates showed resistance to nahdbdc acid and pefloxacin. Moderate number of isolates showed resistance against gentamidn, tetracycline, furazotidone while resistance against enrofloxacin, streptomycin and cotrimoxazole was shown by lesser number of isolates. Least resistant isolates were observed for chloramphenicol. Transfer of drug resistance was also studied. Out of 15 S. gallinarum isolates tested, six (40 per cent) isolates showed ability to transfer drug reastance enbloc against tetracydine gentamicin and sulfamethoxazole while five (3334 per cent) isolates transferred enblock resistance against gentamicin and sulfamethoxazole to recipient E. coli strain. Total 15 (16.3 per cent) isolates out of 92 isolates tested were found to produce bacteriodn. Ten isolates were tested for transfer of bacteriodnogeny, out of which seven (70 per cent) were able to transfer bacteriodnogeny to recipients. coU strain along with multiple drug resistance. Resistance of S. gallinarwn isolates to bacteriddal effects of guineapig and chicken serum was studied Comparative studies with guineapig and chicken serum revealed that all the ten S. gallinarum isolates were resistant to guineapig as well as chicken serum. Eight S. gallinarum isolates resistant to guineapig and chicken serum were also tested for transfer of serum resistance to recipient E. coli. All the isolates failed to transfer serum resistance against guineapig and chicken serum. Pathogenidty of six selected field isolates of S. gallinarwn viz., SG 5, SG 13, SG 31, SG 42, SG 68 and SG 73 was also studied by determining their lethality as well as invasive ability in day old chicks. Day 16 PI results revealed that all the six isolates were equally invasive as no apparant differeces in viable counts (CFU) of these isolates were observed. However, two isolates viz., SG 13 and SG 73 were found more invasive as well as lethal when compared with other isolates as they killed 40 and 60 per cent chicks, respectively. Rest of the isolates viz., SG 5, SG 31, SG 42 and SG 68 were also equally invasive but, the mortahty caused by these isolates was 33.3, 26.6, 6.66 and 6.66 per cent, respectivdy. The isolate SG 5, SG 13 and SG 73 were also tested for transferability of virulence character but the isolates failed to transfer virulence characters. Necropsy examination of all the birds died during an experiment revealed gross lesions like enlargement of liver with bronze discoloration and whitish necrotic foci on its surface, enlargement and congestion of spleen with pin point whitish necrotic foci, enlargement of heart with small rice grain like nodules on its surface, occassional congestion and enlargement of kidney and lungs and severe to moderate congestion of intestinal tract. Efficacy of drinking water medicated with potassium permanganate (PP) at graded concentrations of 1, 0.1, 0.01 and 0.001 per cent in the control of experimental S. gallinarum infection in day old chicks was also assesed. Tlie day old broiler chicks were randomly distributed in five groups (1 to 5) of ten birds each. Chids;s in first four groups (1 to 4) were given drinking water medicated with PP at graded concentration of 1, 0.1, 0.01 and 0.001 per cent respectively, starting at day old age. The birds were simultaneously infected through feed (30 gms/chick) contaminated with live Si gallinarum at the rate of 10 Power 3 organisms per gm of feed. Sxteen days PI results revealed no mortality in chides from 1, 0.1 and 0.01 per cent PP group while 40 per cent chides in control group (group 5) and 20 per cent chicks in 0.001 per cent PP group died. S. gallinarum was reisolated from all dead birds.