[Presence of a sinus conchonasalis in cattle]

It was proved that with 35.7% of the cattle belonging to the breed "Bulgarian Brown" sinus nasalis was observed. It was established starting at the age of one and is connected with the nasal cavity through the dorsal shell sinus. On the basis of these anatomical observations a conclusion was drawn that it was a case of a common sinus conchonasalis, not described so far in anatomy or in clinical practice.