Morphological, molecular, and pathological studies on Prosthogonimus cuneatus in Indian peacocks (Pavo cristatus)

This report provides the first record of Prosthogonimus cuneatus infection in Indian peafowl. Chickens, turkeys, geese, ducks, and other pet birds are recognized as direct hosts of Prosthogonimus species; however, P. cuneatus has not been reported to infect peafowl globally. Here, we identify the trematode present in the bursa of the peafowl by both morphological and molecular methods, in addition to the changes in the bursal tissue induced by the parasite, using histopathology. After a necropsy examination, the trematodes were found in the bursa of Fabricius in three peafowl. Morphological and molecular approaches based on taxonomic characteristics and the sequencing of the trematode-specific internal transcribed spacer (ITS) gene, respectively, were employed for trematode identification. The consensus sequences were compared to P. cuneatus reference sequences from GenBank. In order to assess the pathology caused by the parasite, a histological study of the bursa was also performed. Trematodes were confirmed as P. cuneatus based on morphology and DNA sequencing. Further, histopathological evaluation revealed mild lymphoid depletion of the bursal follicles in both the cortex and medulla with associated thinning of the bursal follicular lining epithelium. Indian peafowl can act as a natural host of P. cuneatus. This study provides a detailed pathological and molecular analysis of P. cuneatus affecting Indian peafowl.