[Mathematical formulations of the fetal mass growth in cattle].
After a short review of investigations into fetal weight growth of cattle, the first mathematical treatment of values gained by Swett and collaborators (1948) and approximated by simple power functions after a proposal from Bereskin and Touchberry (1967) is recalled. Thereafter values for the weight of fetus and uterus with content as summarized by Huth (1962) are approximated with growth functions applying nonlinear regressions. The 6 functions taken into consideration range from classical to quite recent types. Results as listed in 2 tables show remarkable improvements. Parameters and an evaluation of 4 components of fetal development are added. Finally a comparison for the fetus of cattle and the domestic pig shows a lagging behind of cattle by temporarily about 20 percent in relative weight.