SEQUENTIAL RESPONSE OF MILK LEUKOCYTES, ALBUMIN, IMMUNOGLOBULINS, MONO-VALENT IONS, CITRATE, AND LACTOSE IN COWS GIVEN INFUSIONS OF ESCHERICHIA-COLI ENDOTOXIN INTO THE MAMMARY-GLAND

  • 1 January 1983
    • journal article
    • research article
    • Vol. 44  (12) , 2262-2267
Abstract
Temporal changes in the concentrations of leukocytes, albumin, Ig, monovalent ions, lactose and citrate in milk were determined during the initial phases of simulated mastitis. Ten cows whose udders were pathogen free and had milk leukocyte counts of < 0.5 .times. 106 ml/ml were used. Two dosages of Escherichia coli endotoxin were administered to simulate various degrees of mastitis. Two quarters in each cow were infused with the endotoxin; the other 2 served as controls. Quarter milk samples were collected frequently before and after infusion. Within 2 h after infusion of a 100 .mu.g dose of endotoxin, clinical mastitis was observed in most of the infused quarters. Leukocytes, albumin, IgG1 and conductivity showed significant increases. Values before infusion and at postinfusion hour 2 were as follows: leukocytes, 0.33 and 3.65 .times. 106/ml, respectively; albumin, 0.38 and 4.49 mg/ml; IgG1, 0.34 and 0.79 mg/ml; and conductivity, 6.0 and 6.9 mmho [specific conductance]. Average of the peak values and their average relative time of appearance after infusion were as follows: leukocytes, 28.82 .times. 106/ml at 16 h, albumin, 9.37 mg/ml at 4 h; IgG1, 1.35 mg/ml at 4 h; and conductivity, 95.5 mmho at 10 h. The IgG1 values tended to remain high in the presence of rapidly declining albumin concentrations, indicating the possibility of an active, rather than a passive, transfer of IgG1 from the circulation. The response to the 10 .mu.g dose of endotoxin ranged from subclinical to clinically mild mastitis with lesser cellular and humoral responses.