Retrospective study of tongue gangrene in Egyptian buffaloes and its surgical management

Abstract

Tongue gangrene is a rare but serious condition in buffaloes. Despite its clinical and economic importance, it remains poorly documented in Egypt. This retrospective study evaluated the clinical presentation, etiological factors, histopathological findings, and surgical outcomes of tongue gangrene in Egyptian buffaloes. Forty-four buffaloes examined between January 2022 and November 2025 were classified based on the extent of tongue loss, as determined by the length (cm) of the excised gangrenous segment. Microbiological analyses included culture of deep tissue samples from the demarcation zone and rice straw samples taken from the batches fed to affected buffaloes on their farms of origin. Viral RNA was extracted from affected tongue tissues, and FMDV detection and serotyping were performed using RT-PCR targeting the 5′UTR and VP1 regions. Sequenced PCR products were analyzed using BLAST and phylogenetic reconstruction. Partial glossectomy was performed in all cases, and recovery was monitored for up to 24 weeks based on medical records. The buffaloes showed systemic illness with fever and dehydration, along with characteristic dry tongue gangrene (discoloration, foul odor, loss of sensation, and a clear demarcation line). Most cases (31/44) had a recent history suggestive of FMD; the remaining cases were classified as suspected traumatic tongue injury (9/44) or no identified predisposing factor (4/44). Deep tongue tissue cultures yielded bacterial growth in 24/44 and fungal growth in 3/44 cases (presumptive identification), while rice straw samples yielded Fusarium-like fungi (12/44) and clostridia-like organisms (28/44). Histopathology confirmed coagulative necrosis with vascular congestion, bacterial colonization, and neutrophilic infiltration. FMDV serotype O was detected, showing ~ 98% identity by BLAST and clustering within the ME-SA topotype near Egy/Qalyubia/2021. Recovery time correlated significantly with the extent of tongue loss (p < 0.05): the shortest recovery was observed after ~ 5 cm loss, intermediate recovery after ~ 8 cm loss, and the longest recovery among survivors after ~ 10 cm loss. Tongue gangrene in the studied Egyptian buffaloes was most likely associated with recent FMD infection and/or traumatic tongue injuries, which may predispose to microlesions and subsequent microbial invasion. Clostridia-like organisms and Fusarium-like fungi were cultured from deep tongue tissue and from rice straw offered to the affected animals. Early diagnosis and prompt surgical intervention remain essential for successful outcomes and improved survival.