Premium
Effect of parity regimen on the rate of occurrence of mammary tumors in a, C3H, and RIII mice
Author(s) -
Moore Dan H.,
Holben Jane A.
Publication year - 1979
Publication title -
international journal of cancer
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.475
H-Index - 234
eISSN - 1097-0215
pISSN - 0020-7136
DOI - 10.1002/ijc.2910240206
Subject(s) - parity (physics) , regimen , mammary gland , medicine , biology , oncology , cancer research , physiology , breast cancer , cancer , physics , particle physics
The occurrence rates of mammary tumors as affected by breeding regimen (early in life, late, continuous, or not at all) in A, RIII, and C3H mice were observed. The response to the breeding regimen was different in each of the three strains. The C3H stock was affected least, although the tumor occurrence rate was slower in virgins. In both A and RIII, only one litter at puberty resulted in the tumors occurring over the greatest age range; and in RIII mice, the occurrence rate and the mean tumor age were similar to those of the virgins. Normal continuous breeding caused the earliest tumors in all three strains, although in RIII mice, breeding after 18 weeks of age also caused very early tumors. The response of RIII strain to parity variations was more like that of humans than was the response of either of the other strains. Removal of the milk‐transmitted virus from these strains by foster‐nursing resulted in vastly different mammary tumor occurrence rates, the quantitative changes being different in each mouse strain.