Frequency of isolation of environmental XXXX -causing pathogens and incidence of new intramammary infection during the nonlactating period.

@entity5967 @entity794 @entity281 @entity1271 @entity291 @entity4210
Quarter samples (n = 6,328) of mammary secretions were collected from 160 @entity291 during physiologic transitions of the udder to determine the frequency of isolation of @entity1271 -causing pathogens and the incidence of new intramammary infections (IMI) during the nonlactating period. None of the @entity291 in the herd was infected with @entity5967 , and the prevalence of @entity794 was low. @entity291 were not treated with antibiotics at cessation of milking. A threefold increase in the percentage of quarters infected with major @entity1271 -causing pathogens developed from late lactation to early involution. Coliforms and streptococci other than Str agalactiae accounted for 94% of major pathogen infections. The number of quarters infected with coagulase-negative staphylococci increased slightly from late lactation to early involution, whereas the number of quarters infected with Corynebacterium bovis decreased markedly. Major pathogens caused 101 of 153 IMI at parturition and greater than 90% were caused by streptococci and coliforms. At parturition, 51 of 52 minor pathogen IMI were caused by coagulase-negative staphylococci. During early lactation, there was a marked @entity281 with major pathogens; however, the number of quarters with major pathogen IMI during early lactation was 2.3 times higher than the number of quarters infected before cessation of milking. The number of quarters with minor pathogen IMI during early lactation was the same as at parturition, but a marked @entity281 with coagulase-negative staphylococci and a marked increase in @entity4210 IMI developed from parturition to early lactation.
