Immunological dysfunction in periparturient cows: Evidence, causes and ramifications.

摘要

With a $35.7 billion Gross Domestic Value for milk produced in the U.S. during 2007, the dairy industry was the single largest component of the 2007 U.S. animal acpriculture economic engine. The value of milk produced in 2007 represented 30.2% of the total value of animal agriculture production; this figure had grown from $21-23 billion/year a decade ago. The 2 007 NAHMS Dairy Study reported that during 2 006, 23.6% of cows were culled from operations, 26.3% and 23% were removed for reproductive and udder health problems respectively. In addition, 16.5% of cow mortalities were due to mastitis. Clearly, the economic value of controlling mastitis pathogens is immense. Most economic analyses of the cost of maLStitis cite a 10% production loss as only one part of the overall cost of the disease. A majority (65 to 70%) of losses are associated with, decreased milk yield resulting in lower production efficiency; the: remaining costs are attributed to treatment. In addition to these direct losses, mastitis causes significant problems in milk quality control, dairy manufacturing practices, quality and yield of cheesie, nutritional quality of milk, antibiotic residue problems in milk, meat and the environment, and genetic losses dueto premature culling. These additional costs are very significant and.are not always included in economic analyses of mastitis costs.