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Milk yield in rats in relation to activity and size of the mammary secretory cell population

Published online by Cambridge University Press:  01 June 2009

Christopher H. Knight ,
Ann H. Docherty  and
Malcolm Peaker
Christopher H. Knight
Affiliation:
Hannah Research Institute, Ayr, Scotland, KA6 5HL
Ann H. Docherty
Affiliation:
Hannah Research Institute, Ayr, Scotland, KA6 5HL
Malcolm Peaker
Affiliation:
Hannah Research Institute, Ayr, Scotland, KA6 5HL
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Summary

An attempt was made to partition changes in milk yield during lactation in the rat between changes in the size of the secretory cell population and changes in cellular activity. Groups of rats were studied on d 2, 7, 14, 21 and 28 of lactation. Milk yield increased between d 2 and 7, less markedly between d 7 and 14 and decreased between d 14 and 21. Milk secretion had apparently ceased on d 28. Total mammary DNA (DNAt) and RNA (RNAt) increased from d 2 to 14. It is concluded that of the increase in milk yield between d 2 and 14, an increase in cell population accounted for 75% and an increase in cellular activity for 25%. A decrease in activity appeared to be entirely responsible for the decrease in yield between d 14 and 21.

Type
Original Articles
Information
Journal of Dairy Research , Volume 51 , Issue 1 , February 1984 , pp. 29 - 35
Copyright
Copyright © Proprietors of Journal of Dairy Research 1984

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References

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