Immunohistochemical and molecular detection of avian neoplastic disease viruses in layer chickens from poultry farms in Northwestern and Northcentral Nigeria

Viral-induced neoplasms in poultry include Marek’s disease (MD), avian leukosis (AL), and reticuloendotheliosis (RE). Many times, a presumptive diagnosis can be made based on clinical history and histopathology. However, cases of avian neoplasms due to mixed infection of the viruses are common occurrences in the field, which can only be diagnosed using advanced diagnostic methods, hence the need for this study. A 7 and 10 formalin-fixed neoplastic livers from farms in Northwest (Kaduna) and Northcentral (Plateau) states of Nigeria were screened for the presence of Marek’s disease virus (MDV), avian leukosis virus (ALV), and reticuloendotheliosis virus (REV) using immunohistochemistry (IHC) and polymerase chain reaction (PCR). IHC results indicate that all the 17 samples from Kaduna and Plateau States tested negative for ALV-A/B. However, all the 17 samples from the 2 states tested positive for REV. Only 14.3% of the samples from Kaduna State tested positive for MDV1, whereas all the samples from Plateau State tested negative for MDV1. The results of PCR indicate that all the 17 samples from both states tested negative for ALV-A/B/J. However, 57.1 and 50% of the samples from Kaduna and Plateau States, respectively, tested positive for REV, whereas 71.4 and 70% of the samples from Kaduna and Plateau States respectively, tested positive for MDV1. Although, immunohistochemistry and PCR did not offer complete agreement, it is clear that MDV and REV infections are endemic in the study areas. Therefore, a national program for the control and eradication of avian neoplastic disease viruses is recommended.