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Biomedical subjects

B S Samagh

Publications and source records attributed to B S Samagh.

26 records · Page 2Linked to original sources
PubMed1980

Bovine paratuberculosis I. A herd study using complement fixation and intradermal tests.

A dairy herd (102 cattle) which had been enrolled under a paratuberculosis control program for two years utilizing a complement fixation test (carbohydrate antigen) and intradermal skin test (johnin PPD) was subjected to two further herd tests and followed to slaughter to determine infection status by culture and histology. Mycobacterium paratuberculosis infection was demonstrated in 37 of the animals of which only five were considered reactors on the basis of the last two herd tests applied. Cultural and histopathological evaluation indicated the testing procedures had eliminated heavily infected animals. The limitations of these testing procedures under free stall housing conditions are discussed.

Animals↗
PubMed1980

Bovine paratuberculosis II. A comparison of fecal culture and the antibody response.

Fecal culture for Mycobacterium paratuberculosis and a complement fixing serological test using a carbohydrate antigen were compared for diagnostic efficiency in cattle naturally infected with M. paratuberculosis. Serological reactivity was associated with the persistent fecal shedding of large numbers of bacteria and in the absence of false positives in the population studied, was considered an efficient method for the identification of this segment of infected cattle. Minimally infected cattle, which inconsistently shed small numbers of bacteria, were generally serologically negative. One persistent fecal shedder demonstrated a fluctuating serological response to the carbohydrate antigen following abortion. The advantages and disadvantages of this serological diagnostic procedure in relationship to fecal culture are discussed.

Animals↗
PubMed1979

The bovine immune response to Brucella abortus. II. Elimination of some sporadic serological reactions by chelation of divalent cations.

The standard agglutination tests for detecting antibody to Brucella abortus were modified by addition of chelating agents (EDTA and EGTA) to the antigens. Approximately 80% of "singleton" agglutination test reactions, negative on the diagnostic complement fixation test, obtained with cattle sera were eliminated while no decrease in titer was apparent when sera from B. abortus infected or vaccinated cattle were tested.

Agglutination Tests↗
PubMed1979

A rapid plaque neutralization test for bluetongue virus.

A bluetongue virus plaque neutralization test, done in small tissue culture wells (2.0 cm2) using minimal antibody-virus contact time, was found to be of comparable sensitivity to more classical methods involving preincubation. By using the cell culture plates as serum dilution wells and adding cells directly to the virus-antibody mixture, a considerable saving in time is realized. Because of the small size of the wells, reagent cost and incubator space requirements are reduced making the test much more attractive for wide scale use, either as a screening test or one that yields dose-response lines.

Animals↗
PubMed1978

BLV-antibodies in serial sampling over five years in a bovine leukosis herd.

The sequential monthly bleedings of bovine leukosis herd animals showed that a majority of the animals was positive for BLV-antibodies at the age of 1 1/2 years or over and remained reactors throughout the observation period. Two phases of BLV-antibodies were observed in the calves born in the herd. In the first phase the calves remained reactors for two to seven months, indicating residual maternal antibodies acquired through colostrum. In the second phase, the animals became permanent reactors reflecting an active concomitant infection with BLV. The degree of spread of BLV infection among the leukosis herd animals appeared to depend upon the ratio between reactors and negative animals.

Age Factors↗
PubMed1977

Evaluation of radioimmunoprecipitation for the detection of bovine leukemia virus infection in domestic cattle.

The potential application of a recently developed radioimmunoprecipitation test for antibody directed against the major structural protein of bovine leukemia virus was evaluated for use in detection of BLV-infection in domestic cattle. This technique was found to be considerably more sensitive than serologic procedures currently being utilized for this purpose. Radioimmunoprecipitation was also shown to have distinct advantages as compared to hematologic criteria, such as specified by Bendixen's index, for identification of BLV-infected animals. By the use of radioimmunoprecipitation, high levels of antibody to BLV were demonstrated in sera of animals with confirmed adult lymphosarcoma, but not in animals with a less common sporadic form of the disease which occurs in calves.

Aging↗
PubMed1975

A possible autoimmune parathyroiditis following ozone inhalation. II. A histopathologic, ultrastructural, and immunofluorescent study.

Histologic, ultrastructural, and immunofluorescent changes in the parathyroid glands of rabbits have been studied after 48 hours of ozone inhalation at a dosage of 0.75 ppm. The frequent changes observed included hyperplastic parathyroiditis followed by capillary proliferation and leukocytic infiltration. The progressive cytologic events consisted of the presence of eosinophilic leukocytes, reticuloendothelial and lymphocytic infiltration, disaggregation of the parenchyma, and interstitial edema. The ultrastructural changes consisted of degeneration of nuclei, atrophy of the mitochondria, dilatation and atrophy of the endoplasmic reticulum of the chief cells of the parathyroid gland, proliferation of the venous limb of the capillary network, and the prominent interstitial elements. The immunofluorescent techniques revealed positive immunologic response. These data suggest that ozone inhalation perhaps triggers an immune reaction which causes inflammatory injury to the parathyroid gland. The possibility that the modified functional chemical groups of the parathyroid gland act as autoantigen is discussed.

Aerosols↗