EFFECTS OF SOME FACTORS INFLUENCING THE ADHERENCE OF MASTITIS PATHOGENS TO EPITHELIAL-CELLS OF THE BOVINE MAMMARY-GLAND

Adherence was studied tests in vitro, by mixing a bacterial suspension (10(8)/ml) with a suspension of epithelial cells (10(4)-10(5)/ml). Th e bacterial suspension (10(8)/ml) was pretreated with either the beta- toxin of Staphylococus aureus, or blood serum from healthy cows, or mi lk from healthy cows, or blood serum from mastitis affected cows, or m ilk from mastitis affected cows. The effect of mixing a Streptococcus agalactiae suspension (10(8)/ml) with a suspension of epithelial cells (10(4)-10(5)/ml) pretreated with lipoteichoic acid was also examined. Adherence was estimated on the basis of the relative number of epithe lial cells with adhered bacteria, the number of bacteria adhering to 1 00 epithelial cells and the adherence index. The adherence index of St aph. aureus was in the range from 7 to 84, Str. agalactiae 5-80, Micro coccus spp. 27-62 and Str. uberis 16-42. The number of epithelial cell s with adhered Staph aureus was in the range from 16 to 85, Str. agala ctie 32-81, Micrococcus spp. 27-62. Str, uberis 68-82. The number of b acteria adhering to 100 epithelial cells ranged as follows: for Staph. aureus from 100-781, Str. agalactiae 198-578, Micrococcus spp. 90-457 and Str. uberis 128-331. The adherence of Str. agalactiae and Staph. aureus was higher than the adherence of Micrococcus spp. and Str. uber is (P<0,01). Lipotechoic acid, the beta-toxin of Staph. aureus, blood serum from healthy and mastitis affected cows significantly (P<0,01) i nhibited the adherence of Str. agalactiae to epithelial cells of the b ovine mammary gland. The beta-toxin of Staph. aureus, blood serum, mil k of healthy cows and milk of mastitis affected cows significantly (P< 0,01) inhibited the adherence of Staph. aureus to epithelial cells of the bovine mammary gland.