Hygiene around the milking process is very important to deliver a quality product and to maintain a healthy herd.  Micro organisms are transferred from cow to cow by not following a strict cleaning and dipping regime.  Hygiene starts with clean cows where the hair on the udders is short.  Milking gloves, clean towels and a clean cluster are important to eliminate cross contamination.  The use of pre and post dip are essential to maintain clean and healthy teat ends.  At the end of lactation a treatment of dry cow penicilin combined with a teat sealer will guarantee a healthy udder at the beginning of the next lactation.  The chain is as strong as the weakest link.  Do not cut corners with hygiene, it can get really expensive.