| Abstract: | The importance was studied of cowshed strains of K. pneumoniae as causative agents of bovine mastitis. An experiment was conducted with a healthy lactating dairy cow at the age of five years. The microbial inoculum was introduced by a teat tubule, at a dose of 2 ml broth culture 24 hours old. At first, Bac. subtilis was instilled in one udder quarter, to find out the local reaction to nutrient medium, and/or to an uninjurious saprophyte . After five days, a trial was performed on the other udder quarters using three strains of K. pneumoniae, isolated from the rectal contents and the skin of healthy cattle. Finally reinfection followed to study potential allergization of mammary gland. The conclusions as follows may be drawn from the results: 1) Bac. subtilis did not cause any alteration of the main clinic signs, but the inoculated quarter became swollen and its watery secretion contained pus corpuscles. No elimination of bacilli was observed and the morbid condition recovered in five to seven days. 2) After instillation of K. pneumoniae cultures bodily temperature rose by 1.9 degrees C in the course of six hours, all three udder quarters became swollen, showed symptoms of hyperthermia and pain , their secretion also exhibited pathological changes. The NK test revealed highly increased gelling of secretion and pH shift to alkalinity, the number of somatic cells increased 12 to 17 times. The main clinic signs, as well as appearance and consistence of the udder became normal in three days, but the other parameters like NK test and the number of somatic cells in milk normalized in about ten days. 3) Klebsiellae were eliminated from the quarters for one to eleven days, the elimination lasted longer and the counts were significantly higher in capsular strains.(ABSTRACT TRUNCATED AT 250 WORDS) |
