Macrominerals in guinea pig milk during 21 days of lactation.
Milk samples were obtained daily from English short-hair albino guinea pigs for 21 d. Analyses included six macrominerals: Ca, P, K, chloride, Na, and Mg (in order of decreasing concentration). All minerals except K gradually increased in concentration from the beginning to the end of lactation. Calcium concentration began at 38 mM on d 1 and was 78 mM on d 21. The pattern of increase was quadratic: Y (mM) = 39 -.48X (day of lactation) + .11 X2. Phosphorus concentration was 38 mM on d 1 and highest at 51 mM on d 21. Chloride was 19 mM on d 1 and 68 mM on d 21. Sodium was 13 mM on d 1 and highest at 42 mM on d 21. Magnesium was 11 mM on d 1 and was highest on d 18 (13 mM). However, K was 31 mM on d 1, reached a high of 33 mM on d 3, and was lowest on d 19 (12 mM). These changes in concentration and previously reported volume changes suggest alterations in functional capacities of ionic transport mechanisms of secretory cell membranes in this species.
Anderson
R R
RR
Department of Dairy Science, University of Missouri, Columbia 65211.
Sheffield
L G
LG
D000818:Animals; D002118:Calcium / Q000032:analysis; D002712:Chlorides / Q000032:analysis; D005260:Female; D006168:Guinea Pigs / Q000378:metabolism*; D007774:Lactation / Q000378:metabolism; D008274:Magnesium / Q000032:analysis; D008892:Milk / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis; D011188:Potassium / Q000032:analysis; D011247:Pregnancy; D012964:Sodium / Q000032:analysis; D014131:Trace Elements / Q000032:analysis*
D002712:Chlorides; D014131:Trace Elements; D010758:Phosphorus; D012964:Sodium; D008274:Magnesium; D011188:Potassium; D002118:Calcium