Dear All, Attached is the Question Sheet for Diagnostic Exercise #261 contributed by Fabricio Moreira1, Milena Carolina Paz1, Fernado Octavio Mascarenhas Ladeira1, Ana Lucia Schild1 and Claudio Barros2 1Laboratório Regional de Diagnóstico (LRD), Faculdade de Veterinária, Universidade Federal de Pelotas (UFPel), Brazil. 2Laboratory of Anatomic Pathology, School of Veterinary Medicine and Animal Sciences, Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil. *Corresponding author: alschild@terra.com.br Claudio The Diagnostic Exercises are an initiative of the Latin Comparative Pathology Group (LCPG), the Latin American subdivision of The Davis-Thompson Foundation. Members and non-members from any country of residence may contribute to these exercises. Please consider contributing a case to this initiative. It does not have to be unusual, and all pathology sub-specialties are welcome! Please consult instructions on how to format and submit your DE at https://davisthompsonfoundation.org/diagnostic-exercises-instructions/ Previous cases are available at https://davisthompsonfoundation.org/diagnostic-exercise/