On many dairy operations, transition cow disorders account for over half of mature animal health problems. Impaired immune function and a pro-inflammatory state coincide at the start of lactation in many cows, and are linked to increased risk of transition disorders. A growing number of feed and pharmaceutical products are offering a variety of means to attempt to enhance immune function in the transition period, and other tools are being tested for limiting inflammation. Inherent links between inflammation and immunity raise important questions about whether dairies can "have their cake and eat it, too", by improving immunity while avoiding inflammatory conditions. These questions are still being resolved; however, several studies suggest that netbenefits on health and productivity can be achieved. Administration of anti-inflammatory drugs at the beginning of the lactation have substantially increased whole-lactation milk yield while improving retention in the herd. Likewise, feeding immunomodulatory feed additives have enhanced immune response while increasing milk yield,* in some cases. Transition cow strategies have the potential to offer outstanding returns on investment, because of the potential to enhance cow retention and because of long-term carryover benefits on milk production. In summary, although we just beginning to understand altered immune function, inflammation, and their intersection in the transition dairy cow, there are early hints that tweaking these systems can sometimes dramatically improve health and productivity.
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