THE RELATION BETWEEN COGGINS TEST AND ELISA IN THE DIAGNOSIS OF EQUINE INFECTIOUS ANEMIA

Abstract

In the present study 28 horses were used, of which 20 females and 8 males, with ages between 1 and 18 years from Bistrita Nasaud county. For the diagn ose of EIA the official international test (agar ge l immunodiffusion - AGID) was performed in the Sanitary Veterinary Laboratory and for Animal Health in Bistrita, according to the national control plan fo r the disease, in this region (biannual testing). The horses diagnosed as positive to EIA (between 1998 and 2005) were then retested through an enzyme linked immunosorbent assay (the IDEXX EIA cELISA kit) at various periods after their positivity (between 1 an d 7.5 years) to check their disease status. This test was performed on horses' serum at the end of 2006 in t he Laboratory of Infectious Disease Department from the Faculty of Veterinary Medicine Cluj Napoca. After AGID testing, 23 out of 28 tested horses resulted as inf ected with EIAV and the rest of 5 had negative reac tions The results of cELISA were interpreted both visually (a color change) and spectrophotometrical (using the PR1100 Bio- Rad model). From the 23 horses positive at AGID, only 20 presented positive cELISA reactions. The number of negative reactions for EIAV using cELISA increased to 8 horses. Three of the previously posi tive AGID tested horsed turned negative when retested through ELISA (one after 7.5 years, the second after 6.5 years and the third after 1 year from the original testin g). This can be due to the transition of these hors es in an asymptomatic stage of infection, with no circulatin g virus respectively antibodies, at the moment of t esting. Correlation of AGID and CELISA results are excellent if standardized protocols are followed.