STUDIES ON THE INTRAMAMMARY PRESSURE OF DAIRY GOWS

The changes of intramammary pressure (I.M.P.) that occur in the udder of the lactating cow were studied. Results show marked and rapid fluctuations in the I.M.P. at the time of milking. Stimulation by hand manipulation of the udder caused an abrupt increase in pressure, followed by a drop in pressure as milking proceeded. The greater the quantity of milk contained m the udder, the greater the I.M.P. A fall in the I.M.P. of a milked quarter had no effect on the I.M.P. of the unmilked quarters. The I.M.P. rose progressively after milking as measured during milking intervals of 15 and 18 hours.