Removal of Milk Constituents from the Mammary Gland of the Ewe

A NUMBER of experiments was conducted on the ewe to determine the role of lymph draining from the lactating mammary gland in the resolution of the milk constituents. Lymph flowed continuously for many weeks from a polyethylene catheter inserted into the main lymphatic duct draining the mammary gland. Initial investigations were concerned with the changes in composition of the lymph when the lamb was removed from its mother early in lactation. Plasma and lymph samples were collected at intervals for 7–14 days and the concentrations of free fatty acids, volatile fatty acids, cholesterol, phospholipid, total esterified fatty acids, protein, potassium, calcium and inorganic phosphate were measured. In addition, attempts were made to determine the presence of milk proteins in the lymph by the technique of specific precipitation in agar1and also by electro-phoresis on cellulose acetate.