EN
The studies were done in 9 farms on 187 cows affected with a subclinical bacterial mastitis (260 quarters), sub- clinical aseptic mastitis (73 quarters) and latent infections (23 quarters). In the treatment, Lydium-KLP was applied intravenously once at a dose of 0.015-0.020 mg of lysozyme dimmer/kg of body weight. Control examinations carried out on 7, 14, 21 and 28 days after the treatment showed a high effectiveness of lysozyme dimmer in the treatment of subclinical mastitis. From 38.9% to 76.3% infected quarters (average 64.5 %) werer cured in particular farms. Effectiveness of the therapy used was high in cases when one quarter of an udder was affected and a somatic cell count did not exceed 3 million/ml of milk. The cure rate was the following: 50% for quarters infected with S. aureus, 57.9% for quarters infected with S. agalactiae and 88.1% for quarters infected with other microorganisms.