The paper presents a description of the presence of actinomycetes in a male roe deer shot in the south-
western part of the Lublin Upland in 2020. The lesions in the form of porous osteitis involved the right part of the
mandible with a characteristic fistula exiting on the outer side of the mandible. Inflammation also caused the second
molar on this side of the lower jaw to loosen. At the same time, characteristic changes indicating the possibility of
the presence of actinomycetes were found on both antler beams in the area of the outgrowth of the front branches.
Due to the annual cycle of antler application, inflammation must have occurred while the antler was growing. This
is also confirmed by the fact that despite a peculiar anomaly in terms of shape, the development of the antlers has
been completed, as well as it has been wiped out of the scissor and stained. Thus, there was enough inflammation
during the antlers growth, and the disappearance of the pathogen could be related to mechanical damage to the
covering tissue during its growth. The described inflammatory changes did not significantly affect the individual
condition expressed by carcass weight, and had an impact on the shape of the antlers, and above all their weight,
which was significantly lower compared to the average value of this trait for this species in the harvested area.