Resumen: Describimos un caso de encefalitis asociada a infección por astrovirus bovino neurotrópico en una vaca lechera, raza Jersey, del departamento de San José, Uruguay. Este representa el segundo caso reportado de esta condición en el hemisferio sur. La vaca, únicaafectada de un rodeo de 70 bovinos, manifestó signos clínicos neurológicos con curso de 2 días, luego de los que murió espontáneamente. El examen histopatológico reveló meningoencefalitis linfocítica, histiocítica y plasmacítica, con necrosis neuronal, sin cuerpos de inclusión. No sedetectaron en el cerebro otros agentes infecciosos, incluyendo el virus de la rabia (Lyssavirus), alfaherpesvirus bovino-1 y alfaherpesvirus bovino-5 (Varicellovirus), virus de la diarrea viral bovina (Pestivirus), virus del Nilo Occidental (Flavivirus), Listeria monocytogenes, Histophilus somni y otras bacterias. Dado que el descubrimiento de astrovirus neurotrópicos en varias especies de mamíferos, incluidos humanos, es reciente, proponemos que los casos de encefalitis por astrovirus pudieron haber pasado inadvertidos en Sudamérica. Discutimos brevementeel diagnóstico patológico diferencial de encefalitis infecciosas en bovinos. bstract We describe a case of neurotropic bovine astrovirus-associated encephalitis in a Jersey dairy cow from the department of San José, Uruguay. This represents the second case of thiscondition reported in the Southern Hemisphere. The cow was the only one affected in a herd of 70 cows, showing neurological signs with a 2-day clinical course, before dying spontaneously. Histopathological examination revealed lymphocytic, histiocytic, and plasmacytic meningoencephalitis with neuronal necrosis, without detectable inclusion bodies. Other infectious agents, including Rabies virus (Lyssavirus), Bovine alphaherpesvirus-1 and Bovine alphaherpesvirus-5 (Varicellovirus), Bovine viral diarrhea virus (Pestivirus), West Nile virus (Flavivirus), Listeria monocytogenes, Histophilus somni and other bacteria, were not detected in the brain. We propose that given the recent discovery of neurotropic astroviruses in various mammalian species, including humans, cases of astrovirus encephalitis may have gone undetected in South America.We briefly discuss the differential pathologic diagnosis of infectious bovine encephalitis.Abstract We describe a case of neurotropic bovine astrovirus-associated encephalitis in a Jersey dairy cow from the department of San José, Uruguay. This represents the second case of this condition reported in the Southern Hemisphere. The cow was the only one affected in a herd of 70 cows, showing neurological signs with a 2-day clinical course, before dying spontaneously. Histopathological examination revealed lymphocytic, histiocytic, and plasmacytic meningoencephalitis with neuronal necrosis, without detectable inclusion bodies. Other infectious agents,including Rabies virus (Lyssavirus), Bovine alphaherpesvirus-1 and Bovine alphaherpesvirus-5 (Varicellovirus), Bovine viral diarrhea virus (Pestivirus), West Nile virus (Flavivirus), Listeriamonocytogenes, Histophilus somni and other bacteria, were not detected in the brain. We propose that given the recent discovery of neurotropic astroviruses in various mammalian species,including humans, cases of astrovirus encephalitis may have gone undetected in South America.We briefly discuss the differential pathologic diagnosis of infectious bovine encephalitis.© 2021 Asociacion´ Argentina de Microbiolog´?a