scholarly journals Analysis of the effectiveness of the use of enzyme-linked immunosorbent assay for the diagnosis of leukemia in cattle during health-improving activities

Author(s):  
S. I. Loginov

The aim of the work is to analyze the efficiency of using enzyme-linked immunosorbent assay in the diagnosis of cattle leukemia when carrying out health-improving measures in livestock enterprises that are unfavorable for this disease. Indicators of infection of cattle with leukemia virus on 6 farms of agricultural enterprises of the Tomsk region are presented. For serological diagnostics, the immunodiffusion reaction and enzyme immunoassay were used. It has been established that while carrying out health-improving measures in enterprises unfavorable for leukemia in cattle, the use of enzyme-linked immunosorbent assay for serological diagnosis of the disease enabled to identify a greater number of seropositive animals in comparison with a low-sensitivity immunodiffusion reaction. With a decrease in the herd infection rate to single cases of detection of animals infected with the leukemia virus at the final stages of rehabilitation of the enterprise, the number of additional seropositive animals detected by enzyme immunoassay increases. In the final period of herd recovery, the number of animals with a low level of antibodies to the leukemia virus, inaccessible to detection by immunodiffusion, increases. The use of an expensive and labor-consuming delivery of an enzymelinked immunosorbent assay to detect antibodies to the cattle leukemia virus is advisable at the final stages of an enterprise’s recovery. This enables to identify animals with a low level of antibodies to the leukemia virus, to speed up the negative result of a serological test of the entire herd and to exclude repeated outbreaks of infection of animals with this virus in a rehabilitated enterprise.

2021 ◽  
Vol 2 (3) ◽  
pp. 13-17
Author(s):  
Leonid Tarassishin

50 years ago the Enzyme Immunoassay Enzyme-Linked Immunosorbent Assay, mostly known as ELISA was developed. This is a powerful but simple method that is very widely used in the diagnostic practice, as well as in biomedical research. During this time a number of ELISA modification were developed that significantly increased its properties, especially the senstivity, such as avidin-biotin assay, immuno-PCR, nano-ELISA and finally, the digital ELISA. This short review describes the principles of ELISA and the evolution from a conventional assay to the modern ultra-sensitive method. Most of the immunological methods have two components: antigen and antibody. The high specificity of their interaction gives a possibility to detect one of them if other one is included in the reaction as a specific partner. The simplest method for antigen detection in the presence of the antibody is immune diffusion (radial immune diffusion in that case), which practically the formation of precipitate of the “antigen-antibody” complex, when the target antigen diffuses from well into agarose containing the specific antibody. Unfortunately, this assay, as well as other traditional methods, like hemagglutination or complement fixation, have a low sensitivity and are unwieldy.


2004 ◽  
Vol 34 (5) ◽  
pp. 1525-1529 ◽  
Author(s):  
Cristiane Divan Baldani ◽  
Rosangela Zacarias Machado ◽  
Paulo de Tarso Landgraf Botteon ◽  
Felipe Santoro Takakura ◽  
Carlos Luiz Massard

A crude antigenic preparation of Babesia equi was used to develop and establish the suitability of an enzyme-linked immunosorbent assay (ELISA) for the detection of parasite carriers. Optimal dilutions of the antigen, using positive and negative reference sera, were determined by checkboard titrations. The specificity and sensitivity of the ELISA were 100 %. A total of 90 serum samples were taken from horses from the Northeast region of São Paulo State and examined for diagnosis of equine B. equi infection by ELISA. Approximately 75% (n=67) of all the horses tested were found serologically positive for B. equi. These results suggest that the ELISA described may prove to be an appropriate serological test for epidemiological studies on B. equi infections in the field and that equine piroplasmosis is a cause for serious concern in the State of São Paulo, Brazil.


2005 ◽  
Vol 17 (5) ◽  
pp. 451-457 ◽  
Author(s):  
Gustavo E. Monti ◽  
Klaas Frankena ◽  
Bas Engel ◽  
Willem Buist ◽  
Héctor D. Tarabla ◽  
...  

The objective of this study was to validate a new blocking enzyme-linked immunosorbent assay (ELISA) (designated M108 for milk and S108 for serum samples) for detecting bovine leukemia virus (BLV) infection in dairy cattle. Milk, serum, and ethylenediaminetetraacetic acid–blood samples were collected from 524 adult Holstein cows originating from 6 dairy herds in Central Argentina. The M108 and S108 were compared with agar gel immunodiffusion (AGID), polymerase chain reaction and a commercial ELISA. Because there is currently no reference test capable of serving as a gold standard, the test sensitivity (SE) and specificity (SP) were evaluated by the use of a latent class model. Statistical inference was performed by classical maximum likelihood and by Bayesian techniques. The maximum-likelihood analysis was performed assuming conditional independence of tests, whereas the Bayesian approach allowed for conditional dependence. No clear conclusion could be drawn about conditional dependence of tests. Results with maximum likelihood (under conditional independence) and posterior Bayes (under conditional dependence) were practically the same. Conservative estimates of SE and SP (with 95% confidence intervals) for M108 were 98.6 (96.7; 99.6) and 96.7 (92.9; 98.8) and for S108 99.5 (98.2; 99.9) and 95.4 (90.9; 98.1), respectively. The ELISA 108 using either milk or serum to detect BLV-infected animals had comparable SE and SP with the official AGID and a commercial ELISA test, which are currently the most widely accepted tests for the serological diagnosis of BLV infection. Therefore, ELISA 108 can be used as an alternative test in monitoring and control programs.


Sign in / Sign up

Export Citation Format

Share Document