EN
The article describes an outbreak of malignant oedema in a herd of 5 Limousin cows. It was the first outbreak of this kind noted in Poland. The infection developed in cows that had undergone difficult parturition with retained placenta and were in poor condition after being treated unsuccessfully with Oxyvet (tetracycline). Four animals become sick over a 4-month period with the following symptoms: oedema of vulvae and femoral muscles (all the sick cows died, 16% of the herd on the 3-4łh day). C. novyi A was isolated in a pure culture from muscle samples (the isolates produced lethal a and y, e toxins and two haemolysins).