الملخص الإنجليزي
Contagious Caprine Pleuropneumomonia (CCPP) is a severe disease affecting goats in Eastern Africa and the Middle East, caused by the Mycoplasma capricolum subsp. capripneumonia (Mccp). It was previously classified as a member of so-called mycoplasma mycoides cluster and termed as (F38 group). CCPP has been described as the most serious devastating infectious disease of goats in the Sultanate. It is characterized clinically by fever (41-43 °C) and severe respiratory manifestations. The morbidity rate may reach up to 100 % and mortality up to 70% when no control measures are taken. The diagnosis of the disease by means of characterization of the clinical signs is difficult, as many diseases have similar clinical manifestation. Diagnosis of CCPP on the basis of isolation and identification of the causative agent is also difficult, as the pneumonic lesions are often mixed with other pathogens. Many serological tests have been used to evaluate the antibody status of affected goats, however, the specificity of these tests is usually poor as they detect antibodies against antigens of mycoplasma which are shared by other species of the mycoides cluster. Hence the interpretation of the results is often difficult.
A blocking ELISA (B-ELISA) is a new diagnostic tool that was designed for the specific detection of antibodies developed against Mccp in serum of infected goats. It is reported to be highly specific and sufficiently sensitive. In this study, B-ELISA was utilized to evaluate the presence of Mccp-antibodies in 535 serum samples collected from both vaccinated and non vaccinated animals (495 from nonvaccinated animals from Barka, Nizwa and Bahla and 40 samples from vaccinated Batina female animals from Sohar). Goats were selected from various age groups, sexes and breeds from three regions of the Sultanate. The results demonstrated that 47 % of non-vaccinated animals were seropositive for Mccp. There were no significant differences due to age, sex, breed or the three regions. These results are indicative of the widespread presence of Mccp in the Sultanate. Vaccinated animals showed a similar (P>0.05) percentage (50 %) of seropositive cases, suggesting either an inability of the B-ELISA to differentiate between the non-vaccinated and vaccinated animals or that the epitope employed in the B-ELISA is not expressed in the vaccine or that there was vaccination failure.
