Aetiology of the intramammary infections and somatic cell counts in primiparae cows

Abstract

Two hundred primiparae cows from 12 milk properties in the west region of the São Paulo state and north region of Paraná state, were studied. About the animals studied, 86 (43%), showed infections in 140 (17,56%) quarters on the seventh day after parturition. On the first 150 days of lactation, 2372 milk samples were achived. About them, 504 (21,24%) were positive according to the bacteriological test. From the 14th day of lactations on, the microorganisms isolated more often, were the coagulase negative staphilococci (CNS) in 213 (13,52%) samples, Corynebacterium spp in 97 (6,15%) and coagulase positive staphylococci (CPS) in 32 (2,03%). In the same period, the average of the somatic cell counts (SCC) in the infected quarters, were 469 x 103/ml of milk and in the negative quarters, of 79 x 103/ml of milk. In the infected quarters by SCP, Streptococcus spp, CNS and Corynebacterium spp, the average of the SCC, were of 1246 x 103, 1094 x 103, 372 x 103 and 308 x 103/ml of milk, respectively. The SCC when comparated to the opposite non afected quarters, showed significant difference (P < 0,05).