PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “PRECIPITIN TESTS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMedDate not supplied

Use of the agar-gel precipitin test to evaluate broiler breeder and commercial layer flocks for Mycoplasma gallisepticum infection.

In the absence of Mycoplasma gallisepticum (MG) isolation, the importance of agar-gel precipitin (AGP) tests along with microhemagglutination-inhibition (mHI) and serum plate agglutination (SPA) tests for the evaluation of poultry flocks for MG infection was demonstrated. A good correlation between AGP, mHI, and SPA tests for the early confirmation of MG in a flock was observed, except for the breeder flocks from which WVU 907 was isolated. The serums of such breeder flocks were positive for SPA and AGP test but negative for the mHI test. Isolation of MG for confirmation of the status of the flock was unsatisfactory in the later stages of infection or when nonpathogenic organisms were present in appreciable numbers. In the absence of MG or M. synoviae (MS) isolation, demonstration of agglutinin, precipitin, and/or mHI antibodies in the serums of such flocks were confirmatory for MG or MS infection. The new isolate WVU 907 gave positive reactions on the SPA and AGP tests with MG antiserum. The isolate hemagglutinated chicken red blood cells (RBC) and induced low HI antibody levels (less than or equal to 1:20) when inoculated into chickens. Like MG, WVU 907 precipitin antigen was partially denatured by urea, Triton x-100, and sodium dodecyl sulfate treatment.

Agglutination Tests↗
PubMed2000

Application of the agar gel precipitin test to detect antibodies to Salmonella enterica serovar enteritidis in serum and egg yolks from infected hens.

Serological surveillance can be an important component for egg quality assurance programs geared toward controlling problems with Salmonella enterica serovar Enteritidis (S. enteritidis) within a flock. Serum is the primary sample source for the procedures, although egg yolk antibody assays have become popularity in recent years. However, these assays tend to be labor intensive, requiring procedures for extracting antibodies from the yolk followed by assaying the samples. We describe an adaptation of the agar gel precipitin (AGP) test for use in detecting antibodies to S. enteritidis deposited in egg yolks of infected hens. Yolk or sera from infected birds were administered to wells cut into seven-well clusters in an agar gel plate, and detection antigen was added to the center well. The agar gels were incubated for 24 h and then examined for the presence of precipitin lines formed by the interaction of antibody with antigen. Three different antigens were tested: S. enteritidis flagella, SEF14 (a 14-kDa fimbrial protein produced ostensibly by S. enteritidis), and a sodium deoxycholate extract of whole S. enteritidis organism. Flagella and the organism extract detected antibodies to S. enteritidis in the yolk and sera, whereas SEF14 was not reactive. Positive reactions were observed in serum 1 wk postchallenge, whereas in yolks, this was further delayed by 1 wk. The sensitivity of the test was slightly less than the standard microagglutination assay, although specificity was slightly higher, as indicated by results from sera and yolks from birds infected with Salmonella enterica serovar Typhimurium. Simplicity and low labor requirements of the assay would allow for the potential testing of several hundred egg samples within a day, which would make up for test shortcomings due to sensitivity. The AGP test could be an important tool for individuals using serological testing to monitor the S. enteritidis situation within their flocks or as a rapid screen for vaccine responses. The assay could also be used in tandem with other AGP tests to screen for the presence of multiple avian pathogens.

Animals↗