PubMed HealthSearch

Biomedical subjects

B S Pomeroy

Publications and source records attributed to B S Pomeroy.

At least 19 recordsLinked to original sources

Enzyme-linked immunosorbent assay for the detection of Salmonella enteritidis infection in chickens.

An ELISA was developed and tested for its ability to detect antibodies against Salmonella enteritidis in chickens. Various features of the ELISA were evaluated and optimized. The outer membrane protein antigens selected by use of the protein immunoblotting method made the assay specific and sensitive. The assay was evaluated in chickens experimentally infected with S enteritidis. Blood samples collected at weekly intervals after experimental infection with S enteritidis were analyzed by ELISA. Results of the ELISA were compared with those of conventional serum plate and microagglutination tests. The ELISA was more sensitive and specific in the detection of S enteritidis infection than the other 2 conventional tests.

Animals

Secretory antibodies against turkey coronaviral enteritis.

Studies on local immunity to transmissible coronaviral enteritis of turkeys (bluecomb) was made. Intestinal secretions and bile from affected birds contained secretory immunoglobulins against coronaviral antigen throughout the 6 months' duration of the experiment. Attempts to purify and to characterize the globulins in intestinal secretions and bile of the affected birds were made, using the techniques of gel filtration, DEAE chromatography, and immunoelectrophoresis. Class-specific anti-turkey IgA antiserum in the agar gel precipitin test further established the presence of IgA in the intestinal secretions and bile.

Animals

Isolation of type A influenza and Newcastle disease viruses from migratory waterfowl in the Mississippi flyway.

Twenty-seven chicken red blood cell agglutinating agents were isolated from 187 tracheal swabbings of apparently healthy migratory mallard ducks (Anas platyrhynchos) in the Mississippi flyway. Twenty-four of the isolants were type A influenza virus; 3 lentogenic Newcastle disease viruses were isolated. Isolations were not made from either 65 giant Canada geese (Branta canadensis) or 60 Franklins' gulls (Larus pipixcan).

Animals

Characteristics of two new reticuloendotheliosis virus isolates of turkeys.

Reticuloendotheliosis (RE) virus strains MN81 and MN67 isolated from epiornithics of RE in turkeys were partially characterized. Strains MN81 and MN67 replicated in chicken embryo fibroblast,duck embryo fibroblast and turkey embryo-fibroblast cultures and produced syncytial cytopathic effects in duck embryo fibroblast and turkey embryo fibroblast cultures. The virions of MN81 and MN67 measured approximately 100 nm in diameter, resembled RE virus strain T, and could be distinguished from avian leukosis viruses morphologically. The buoyant density of strain MN81 was found to be 1.15 g/cm3 in sucrose gradients. Strains MN81 and MN67 were inactivated by heat, acid pH, ether, and chloroform treatments. These strains were serologically unrelated to avian leukosis virus but were related to RE virus strains T, CS, DIA, and SN.

Animals

Detection of turkey coronaviral enteritis (bluecomb) in field epiornithics, using the direct and indirect fluorescent antibody tests.

In Minnesota, efforts have been made over the past 10 years to eliminate turkey coronaviral enteritis (TCE, bluecomb) by controlled depopulation and decontamination with a rest period before restocking. In 1973, clinical observations indicated that bluecomb was restricted to one limited area in Minnesota. Five epiornithics occurred during late 1973 and 1974, involving 5 different farms in this limited geographic area. During 1975, 3 epiornithics of TCE were investigated, involving 185,000 turkeys in 17 flocks, of which approximately 17,000 died. Naturally infected turkeys representing 7 operations between 1973 and 1976 were examined by both the direct fluorescent antibody test and indirect fluorescent antibody test (IFAT). The direct fluorescent antibody test detected coronaviral antigen in intestinal tissues during the acute phase of the disease, and the IFAT was highly useful in detecting TCE serum antibodies of turkey flocks that had recovered and were potential carriers. Therefore, an IFAT surveillance program was instituted for replacement flocks on farms where clinical epiornithics of TCE had occurred in 1974 through 1976. Operation 5 involved TCE epiornithics over a 2-year period and illustrate the importance of complete depopulation with an intensive decontamination program.

Animals

Development of microagglutination test for detecting Arizona hinshawii 7:1,7,8 infection in turkeys.

A microagglutination antigen treated with tetrazolium dye was produced. The culture used was rendered nonmotile by growing in medium containing 1:1,000 concentration of phenol. A trial was conducted by infecting freshly hatched turkey poults with Arizona hinshawii 7:1,7,8. An equal number of poults were kept as negative controls. Starting with 4-week-old poults, blood samples, cloacal swabs, and environmental samples were obtained at 2-week intervals up to 16 weeks of age. The serum samples were tested by using tubeagglutination (TA), serum plate agglutination (SPA), and microagglutination (MA) tests for A hinshawii 7:1,7,8. A field trial was conducted, using known negative and infected turkey flocks, and serum samples were tested by MA, SPA, and TA tests. The results indicated that MA test was far more sensitive and superior to TA and SPA tests in detecting turkeys infected with A hinshawii 7:1,7,8. The field trial confirmed the laboratory trial observations.

Agglutination Tests

Susceptibility of turkeys to Georgia strain of Marek's disease virus of chicken origin.

Two experiments were conducted to study the susceptibility of turkeys to Georgia strain of Marek's disease virus (MDV). One-day-old chickens and turkeys were experimentally inoculated with Marek's disease (MD) infective plasma (experiment 1) or tumor homogenate (experiment 2) and raised in isolation for 29 weeks. The MDV inoculums were pathogenic for chickens and turkeys and caused high mortality (chickens, 100% and turkeys, 70%). Macroscopic lesions of MD were observed in liver, spleen, lungs, proventriculus, and other viscereal organs. Microscopically, affected tissues were infiltrated with the pleomorphic population of neoplastic lymphocytes. Uninoculated turkeys did not show gross or microscopic lesion of MD. The MDV was reisolated from the experimentally inoculated, but not from the uninoculated, chickens and turkeys. Antibodies to MDV were detected in experimentally infected chickens. Uninoculated chickens and all turkeys lacked precipitating antibodies to MDV. The present study suggests that turkeys are highly susceptible to experimental infection with GA strain of MDV.

Animals

Naturally occurring reticuloendotheliosis in turkeys: transmission.

This report describes the natural occurrence and experimental transmission of reticuloendotheliosis in a turkey flock. In the naturally affected turkeys, lesions were present in the liver, spleen, heart, intestines, and peripheral nerves, and were composed mainly of lymphoreticular cells. The disease was experimentally reproduced in turkey poults with cellfree tissue extracts of infected birds. A type-C RNA virus similar to reticuloendotheliosis virus (strain T) was present in the tissues of turkey poults experimentally inoculated. This virus was unrelated to the type-C RNA viruses of the avian leukosis sarcoma complex.

Animals

Effects of different levels of chlortetracycline in the diet of turkey poults artifically-infected with Salmonella typhimurium.

Two separate experiments were conducted to assess the shed rate and duration of shed of S . typhimurium organisms from turkey poults orally infected with chlortetracycline-sensitive S. typhimurium in relation to chloretetracycline (CTC) given in the feed at 0, growth promotant, subtherapeutic and therapeutic levels; the emergence of resistant S. typhimurium organisms in reference to the diet given; in vitro transfer of drug resistance from thses resistant S. typhimurium donor cultures to multiply-sensitive E. coli recipients; and phage type changes, is any, of these S. typhimurium isolates. The results showed that increasing CTC in the diet from 0 to the three levels of antibiotic supplementation, appeared to (a) reduce shed and duration of shed corresponding to each level used; (b) cause a minimal development of drug resistance and its transfer (usually at sub-therapeutic levels of CTC supplementation) for the duration of the experiment; and (c) induce phage type changes in some of the S. typhimurium isolates. These phage type changes question the validity of using phage typing as a tool in epidemiological investigations.

Administration, Oral

Scanning electron, light, and immunofluorescent microscopy of coronaviral enteritis of turkeys (Bluecomb).

Intestinal sections from both experimental and field cases of turkey coronaviral enteritis (TCE) were examined by scanning electron microscopy and light microscopy through 10 days after inoculation and by a direct fluorescent antibody test for TCE through 12 days. Serums were collected for an indirect fluorescent antibody test for TCE through 160 days after inoculation. Lesions observed with the scanning electron microscopy were catarrhal enteritis with hemorrhage per diapedesis, epithelial desquamation, and villous atrophy which developed and regressed within 6 days after inoculation. Light microscopy demonstrated similar lesions, except that villus-to-crypt ratios remained depressed 10 days. The direct fluorescent antibody test demonstrated the presence of coronaviral antigen throughout the sampling period, and serum antibodies to TCE were present until at least 160 days, when the experiment was terminated.

Animals

In vitro and in vivo transfer of drug resistance for Salmonella and Escherichia coli strains in turkeys.

In vitro and in vivo transfers of antibiotic drug resistance were observed when isolates of multi-resistant Salmonella saint-paul and Escherichia coli donors were mated with multi-sensitive E coli and Salmonella typhimurium recipients, respectively. For in vivo studies, day-old turkey poults were used. Drug resistances were transferred either alone or in various combinations. In vitro, transfer was more frequent from E coli to S typhimurium; in vivo, transfer was more often observed from S saint-paul to E coli. Transfer occurred in vivo within 3 or 6 days after the recipient strain was given to poults previously infected with donor bacteria. In some instances, phage typing of S typhimurium indicated a change after transfer of drug resistance from E coli to S typhimurium. The criteria for in vivo transfer of drug resistance were discussed, and the implications of a change in phage type were noted.

Animals

Indirect fluorescent antibody test for the diagnosis of coronaviral enteritis of turkeys (bluecomb).

Frozen sections of intestine obtained from experimentally infected embryos were satisfactory as a suitable antigen in the indirect fluorescent antibody (IFA) test for detection of antibodies to turkey coronaviral enteritis (TCE). Antibodies were detected in infected turkeys at 14 days after infection and persisted for at least 107 days when the 1st experiment was concluded. Antibodies were also detected in infected turkeys at 9 days after infection and persisted for at least 160 days when the 2nd experiment was terminated. The IFA test may be of value as a rapid and economical screening method for TCE antibodies.

Animals

In vivo spread of infectious drug resistance in turkeys.

Multiresistant Salmonella typhimurium donor and multisensitive Escherichia coli recipient spread from the infected group of turkey poults to the control group. Contact poults given only the S typhimurium donor and placed in the same cage with infected poults given both the donor and the E coli recipient exhibited in vivo patterns of antibiotic drug resistance transfer similar to the patterns obtained in the infected poults. This in vivo spread of antibiotic drug resistance in turkeys was established for the first time. Results indicated that the potential in vivo spread of infectious drug resistance could occur in nature.

Animals

Isolation and characterization of viruses from natural outbreaks of reticuloendotheliosis in turkeys.

We have described the in vitro isolation of type-C RNA viruses from two outbreaks of a fatal neoplastic disease in turkeys we diagnosed as reticuloendotheliosis. The virus had a density of 1.16 g/ml in sucrose gradients, had a DNA polymerase capable of using both endogenous and exogenous (synthetic) templates, and was infectious in vitro for turkey and chick cells. The culture-propagated virus was oncogenic for turkeys. The virus isolates were unrelated to avian leukosis virus and antigenically identical to reticuloendotheliosis virus (REV) strain T. Thus our studies suggested that REV is a causative agent of naturally occurring, fatal leukosis in turkeys.

Animals

Antibiotic dipping studies in relation to uptake, embryonic development and Arizona hinshawii recoveries from turkey hatching eggs.

Antibiotic dipping with gentamicin sulfate by means of the temperature-differential method was effective in reducing but not completely eliminating Arizona hinshawii (7:1, 7, 8) from artificially infected turkey hatching eggs. Embryonic development was well maintained. The antibiotic dip solution intake was variable from egg to egg. Removal of cuticle by means of either 0.2 N HCl or a 10% disodium salt of ethylene diamine tetraacetic acid enhanced egg weight gains and maintained good embryonic development. Complete elimination of A. hinshawii was achieved in one experiment out of four. Correlation studies between egg weight gains and gentamicin concentrations of the contents of the turkey hatching eggs indicated a statistically significant relationship between these two parameters.

Animals