Physical state of mother at the period of pregnancy and sexual maturation of descendants-sons of the water vole (<Emphasis Type="Italic">Arvicola terrestris</Emphasis> L.)

The role of characteristics of the maternal medium (the mother’s physical state at periods of pregnancy and lactation, calendar terms of birth, the number of pups, and the ratio of sexes in the litter) has been elucidated in regulation of growth and the sexual maturation of the water vole male pups. The anogenital distance was used as an indirect supravital evaluation of the mass of testicles. The physical state of females was estimated by a change of the body mass at the period of pregnancy or lactation with aid of parameters characterizing deviation of the female body mass after the end of each reproductive cycle stage from the calculated value found from the empirical regression equation. Sons of the females whose body mass increment for the period of pregnancy exceeded the expected value or was equal to it were growing faster. Results of regression analysis have shown that the anogenital distance in the 19-week old males is dependent statistically significantly only on the physical state of the mother at the period of their embryonic development.