NSE and GFAP expression in the brain of clinically normal ducks

The brain of ducks is highly susceptible to different health issues that might not show symptoms immediately. Both Neuron-Specific Enolase (NSE) and Glial Fibrillary Acidic Protein (GFAP) are considered as promising biomarkers for unmasking of neuronal diseases. Due to the lack of information about histopathological changes alongside NSE and GFAP expression in ducks during normal conditions, the current study’s aim was to explore these potential changes in the brain tissue. Therefore, a total number of fifteen adult healthy ducks of both sexes were collected from local markets in Mosul city during the period from February to April 2024. Brain samples were collected and underwent to full post-mortem investigation, routine histological evaluation, and immunohistochemistry for protein expression of NSE and GFAP. Results showed absence of gross changes in the examined brain tissues. However, microscopic examination revealed diverse pathological changes at different severity scores in particular vacuolar degeneration, inflammation, edema and parasitic infection represented by Sarcocystis. Besides, both NSE and GFAP were expressed in different intensities in the brain tissue. Nonetheless, NSE severe expression was observed in seven samples (46.7%), followed by moderate expression in five samples (33.3%), and mild expression in only three samples (20%). Surprisingly, GFAP exhibited negative expression in only one brain sample (6.7%), followed by four samples (26.7%) which exhibited moderate expression. Notably, both mild and severe expressions were seen in the same percentage (33.3%). We conclude that healthy ducks can exhibit histopathological changes and NSE exhibited more intense expression than GFAP in the absence of induced-brain damage.