Toxoplasmosis and neosporosis are diseases of livestock worldwide caused by infections with closely
related parasitic protozoa, T. gondii and N. caninum, respectively. Toxoplasmosis is a cause of reproductive
failure in small ruminants and zoonotic, while neosporosis is a major cause of bovine abortion without zoonotic
reports. The clinical signs associated with both infections are often nonspecific. Therefore, serological diagnosis is
important for detection of specific antibodies induced by the infection. However, propagation of T. gondii and
N. caninum tachyzoite in vitro or in vivo is required prior to crude antigen extraction, high risk in contamination
of cell culture or animal facilities for parasite propagation and time-consuming process. With the use of
recombinant proteins as antigens, the risk of handing viable parasites can be avoided with improving in sensitivity
and specificity for the detection. Although some of T. gondii or N. caninum recombinant proteins showed a high
efficacy for diagnosis, more validation and optimization are still needed to provide a high throughput performance
for using in animals. This review presents advance in the application of recombinant antigens as a serological
marker for the above parasites detection in livestock.