Objective: to provide an update on current knowledge on udder health during dry period withcomparing different types of management methods. Defining the problem: Dry period is a crucial phase for the bovine mammary gland to regenerate after the end of lactation. This period is necessary to render an appropriate milk yield during the subsequent lactationand appropriate management in this period have a great impact on the incidence of clinical mastitis in the next lactation. The main objectives of dry cow therapy are as follows: Eliminating existing IMI present at drying off Preventing new IMI during the dry period and around calving Establishment of contagious and environmental mastitis pathogens have relevance to the dry period. Two periods of increased susceptibility during the dry period have identified; 1)the first three weeks after cessation of lactation and the period immediately prior to parturition. Compared to cows receiving no treatment at drying off, cows receiving a dry cow therapy have a reduction in the frequency of new infections during the dry period and incidence of periparturient clinical mastitis. The dry period offers the best opportunity in the lactation cycle to curing existing infections for the following reasons: higher cure rates; higher doses of antibiotic can be used; Treatment duration and retention time in the udder is longer. Different scenarios for dry cow udder management can be listed as follows: Blanket dry cow therapy, selective dry cow therapy based on cows or quarters, systemic dry cow therapy, shortening the dry period,using teat sealants, vaccination, immune modulators, etc.Lactation is ended with either abrupt or gradualcessation of milking; these methods of milk cessation have impact on new infection at dry period.

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