CHARACTERISTICS OF MAMMARY SECRETION DURING EARLY LACTATION FROM NATURALLY-CALVING DAIRY-COWS AND COWS INDUCED TO CALVE PREMATURELY

Changes in the composition of mammary secretion from Friesian and Jers ey cattle were monitored during the first two weeks after commencement of milking. Measurements were made on naturally-calving cows and heif ers and on cows induced to calve prematurely. Irrespective of breed or age of animal or whether calving was natural or prematurely induced, the patterns of change were similar relative to the time of commenceme nt of milking, not parturition. Although the characteristics of secret ion continued to change during the first 10 or so days after milking c ommenced, by 5 days the secretion resembled normal milk. It was appare nt that measurements based on somatic cell count and concentration of immunoglobulin G1 could be used as the bases for a quality payment sch eme to encourage supply of milk suitable for the manufacture of qualit y dairy products.