MASS INCIDENCE OF STILLBIRTH CAUSED BY CA RBON-MONOXIDE INTOXICATION IN A PIG BREEDING STOCK

In a cold winter, only stillborn or non-viable piglets were born by 22 sows in a relatively small, completely closed farrowing house heated by gas infra lamps during a period of one months. The sows showed no c linical symptoms and after farrowing showed normal heat and their inse mination was successful. The pathological examination of stillborn pig lets showed no pathognostic alterations. The subcutaneous connective t issue showed oedematic infiltration, the parenchymatic organs were inf iltrated by haemoglobin. The laboratory investigations excluded the ro le of different viruses and mycotoxins in the cause of stillbirth. Aft er the improvement of ventilation, the carbon monoxide concentration m easured at the floor level (80 to 102 mg/m(3)), as well as the COHgl c oncentration of the blood of sows (10 to 12%) still were significantly high. After the improvement of ventilation and changing the gas heati ng for electric heating system, no other cases of stillbirth were obse rved. After having analyzed the circumstances of the disease and resul ts of laboratory investigations, the cause of losses could he traced b ack to carbon monoxide intoxication.