Agar-gel Diffusion Precipitin Test Research Articles

An outbreak of chronic fowl cholera in broiler breeder chickens in Korea

Fowl cholera is a contagious acute and chronic disease caused by Pasteurella multocida in both domesticated and wild birds. Acute fowl cholera in both chickens and wild birds has recently been documented in Korea, but the chronic form has not been reported in Korea until now. This study describes the first outbreak of chronic fowl cholera in 13-week-old Arbor Acre broiler breeder chickens submitted to the College of Veterinary Medicine, Kyungpook National University in April 2006. The clinical signs of the affected flock of 9,621 chickens were lameness caused by swollen hock joints, diarrhea, ruffled feathers, and an average weekly mortality of 1.0%. At necropsy, purulent or caseous exudates were found in the hock and wing joints, humerus, and eyes, and severe pneumonia and pericarditis were discovered. Eleven bacterial isolates obtained from the liver, joint, infraorbital sinus and sternal bursa of the submitted chickens were all identified as Pasteurella multocida based on their physiological and biochemical characteristics. Five isolates were examined for antimicrobial susceptibility against 21 different antimicrobial agents including ampicillin. All were resistant to kanamycin, neomycin, and streptomycin, and some were resistant to gentamicin. The tested isolates were all susceptible to the other 17 antimicrobial agents. All 11 isolates were capsular serogroup A based on multiplex polymerase chain reaction. In addition, two of five isolates used in the antimicrobial susceptibility test were identified as somatic serotype 1 by an agar gel diffusion precipitin test, while the others were non-typable.

Serological reactions in sheep and cattle experimentally infected with three Australian isolates of bluetongue virus

Serums from 103 sheep and 24 cattle experimentally infected with one of 3 serotypes of bluetongue virus isolated in Australia were tested for antibody to bluetongue virus in the serum neutralisation test and the agar gel diffusion precipitin test. Antibody to bluetongue virus was first detected by these tests 8 to 10 days after intravenous infection in 4 sheep that were bled daily for serum analysis. The agar gel diffusion test failed to detect antibody in 28% (29/103) of sheep which had seroconverted in the serum neutralisation test. A further 7% (7/103) of sheep serums were negative in both tests 14 to 22 d after infection. Both tests detected antibody to bluetongue virus in all cattle serums by 10 days after detection of viraemia. In comparison with the intravenous route of infection, extended prepatent periods for the commencement of viraemia resulting from intradermal, subcutaneous and intrauterine routes of infection in the cattle caused corresponding delays in the detection of antibody. For example, one cow that was infected by intrauterine inoculation did not become viraemic until 22 d after inoculation and antibody was not detected until 32 d after inoculation.

Immunoglobulin class of antibodies in monkeys infected with Toxocara canis

Sera of monkeys ( Macaca sinica), experimentally infected with multiple doses of eggs of Toxocara canis, were subjected to Sephadex G-200 gel filtration and DEAE cellulose ion exchange chromatography. The distribution of antibodies in the various serum fractions was determined by the conglutinating complement absorption test (CCAT) and the agar-gel diffusion precipitin test using antigens prepared from the adult and the embryonated eggs of T. canis and by the formation of precipitates at the oral orifice of artificially hatched living 2nd stage larvae of T. canis. In serum samples taken 1 and 2 weeks after initial infection, CCAT antibodies were located mainly in the macroglobulin fractions of serum. By 1 to 4 weeks after a third dose of eggs such antibodies were located mainly in the 7S fraction of immunoglobulins. Antibodies detected by gel precipitation were located in the macroglobulin fraction of serum, while those that produced oral precipitates on 2nd stage larvae occurred in the 7S fractions.

Antibody in Cattle Experimentally Infected with Contagious Bovine Pleuropneumonia

Antibody responses in cattle experimentally infected with contagious bovine pleuropneumonia were assayed by the complement fixation (CF), plate agglutination (PA), and agar-gel diffusion precipitin (AGDP) tests. Sera were also fractionated by sucrose gradient centrifugation, by chromatography on diethylaminoethyl (DEAE)-cellulose columns, and by starch-block electrophoresis. Serum fractions were assayed for antibody by the CF and PA tests. Antibody was detected by the CF and PA tests from 7 days postinoculation (DPI) throughout the test period of 154 days. The AGDP test was the least sensitive and was negative after 28 DPI. By sucrose gradient centrifugal analysis, only 19S antibody could be detected in the 7 DPI sera, but 19 and 7S antibodies were found in the 14, 21, 28, 35, and 42 DPI sera. Only 7S antibody was found in sera subsequently collected until 154 DPI at the conclusion of the experiment. Results of chromatographic fractionation of sera on DEAE-cellulose columns showed that most of the CF antibody was adsorbed when 0.0175 m phosphate buffer (pH 6.3) was used for elution of proteins. Plate agglutination antibody activity was found in both immunoglobulin (Ig)G and IgM fractions from 7 to 42 DPI and only in the IgG fraction thereafter. By starch-block electrophoresis, the 14 DPI antibody was of beta mobility (IgM), whereas at 21 DPI the antibody mobility was gamma-beta. In the 28 and later DPI sera, CF antibody had gamma mobility.

Comparative studies of antigens from Mycoplasma mycoides and Escherichia coli.

Extracts of sonically disrupted Mycoplasma mycoides and Escherichia coli were fractionated by sucrose density gradient centrifugation. The presence of antigen in each of the fractions was determined by complement-fixation and agar-gel diffusion precipitin tests, in which cow, pig, and rabbit anti-M. mycoides sera and rabbit anti-E. coli serum were used. Fractions of M. mycoides, with a buoyant density of 1.225 or lower, fixed complement with cow and pig anti-M. mycoides sera. These fractions also formed precipitin lines with pig antiserum. Fractions in the buoyant density range of 1.10 to 1.20 fixed complement with rabbit anti-E. coli serum, but precipitin lines were not formed. All E. coli fractions fixed complement and gave precipitin lines with homologous serum. But fractions in the buoyant density range of 1.10 to 1.20 had minimal complement fixation with heterologous M. mycoides sera. The cross-reacting antigens in M. mycoides and E. coli had a buoyant density of 1.10 to 1.20; the specific antigens were isolated from M. mycoides at a buoyant density of 1.08 to 1.02.

Electron microscopy of the interaction of African swine fever virus with ferritin-conjugated antibody.

Abstract Two isolates of African swine fever virus were studied by electron microscopy of interactions with ferritin-conjugated antibody, complement fixation, and agar gel diffusion precipitin tests. The viruses, Lisbon-57 and Tengani, were tested with anti-body to the Lisbon-57, Tengani, Salamanca, and Hinde isolates. Correlation of the data from these three independent methods indicates that the similarities between isolates are greater than the differences and that, perhaps, no differences exist.

Immune sera in the study of food antigens: II. Crustaceans

1. 1. Sera from specifically immunized rabbits were employed in agar-gel diffusion precipitin tests in the qualitative antigenic analyses of crustacean extracts. 2. 2. Multiple antigenic components (4–9) were demonstrated in the edible abdominal muscles of lobster, crab, shrimp, lobster tail, and fresh-water crayfish and in the bodies of entomostracans (“insect type” crustaceans), daphnia and brine shrimp. 3. 3. Only a partial degree of qualitative cross-antigenicity was noted among various taxonomically related edible shellfish, and an antigen common to all five could not be demonstrated. 4. 4. Partial qualitative cross-antigenicity was noted among taxonomically related entomostracans (“insect-type” crustaceans), Artemia salina (brine shrimp) and Daphnia pulex (water fleas). Some antigenic components of brine shrimp were common to those of the edible malacostracans (shellfish), whereas daphnia contained antigen common only to ecologically related freshwater crayfish. 5. 5. A wide qualitative variation among individual component antigens of crustaceans was demonstrated in homologous species skin-testing extracts of different laboratory sources.

Immune sera in the study of food antigens: I. Fish

1. 1. Sera from specifically immunized rabbits were employed in agar-gel diffusion precipitin test techniques in the qualitative antigenic analyses of fish extracts and fish-derivative preparations. 2. 2. Fish antigens were demonstrated in some samples of cod- and halibutliver oils, with wide variations in components existing among different lots of these materials. 3. 3. Antigenic fish constituents could not be detected in the emanations of raw, fried, or boiled cod and halibut. 4. 4. Fish antigens were identified in protamine and sodium morrhuate. 5. 5. The antigenic components of fish roe did not demonstrate cross-antigenicity with egg proteins of chicken origin. 6. 6. A wide qualitative variation among individual component antigens of fish muscle was demonstrated in homologous species skin-testing extracts of different laboratory sources.