Experimental Coliform (Aerobacter Aerogenes) Mastitis: Distribution of Whey Proteins During the Early Acute Phase

Two trials involving inoculation of lactating quarters of one cow with large numbers of Aerobacter aerogenes are described. Only a mild reaction occurred following the first inoculation. Acute mastitis was produced in the second, with agalactia resulting in all quarters by the fourth inilking after exposure. All glands returned to full normal production by 2 wk. In both trials, evidence of increased permeability between blood and milk (increased pH, chlorides, serum albumin, and immune globulin) took place within 3 hr. Serum albumin declined rapidly to normal levels, but the inmmne globulin fraction remained elevated. Following the period of agalaetia, a protein here designated X, with a paper electrophoretie mobility intermediate between a-laetalbumin and immune globulin, appeared. The X protein ultinmtely completely masked a-lactalbumin and comprised as much as 50% of the total whey protein. It disappeared from whey after the glands returned to full milk production. A similar protein was also found in wheys obtained from cows early in the dry phase of lactation. It did not appear to have the paper electrophoretie mobility of any of the major electrophoretic components of blood or milk. It was postulated the X protein was of cellular origin.