Abstract
SUMMARY Extracts of jugular-vein blood of pregnant cows and of cows in oestrus were treated with methanolic HCl and phenolic fractions prepared. Assay by the mouse uterine-weight method failed to detect oestrogen in fractions from cows in oestrus or 2–3 months pregnant but indicated the presence of oestrogen, equivalent to about 1 μg. of oestrone/l. in blood from cows 5–6 months pregnant and about 7 μg./l. in blood from cows 7–9 months pregnant. The activity of the phenolic fraction from blood of late pregnancy was shown to be due mainly to oestrone, most of which had been present in the blood as a water-soluble derivative. Similar fractions from blood of cows in oestrus, assayed by the tetrazolium method of Martin, showed a total of 1–10 ng./l. (expressed as oestrone) activity being in the non-ketone and ketone fractions.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
