Materials and Methods: In the present study, 30 Holstein cattle fetuses were used. Ten fetuses, belonging to each of the early, mid- and late gestational stages were evaluated. Accordingly, in total, 60 kidneys were assessed after bilateral dissection for three different renal parameters (length, width, thickness). The morphometric data obtained from the kidneys was subjected to statistical analysis.

Results: In general, throughout gestation, all renal measurements were significantly correlated with gestational age. The length and width of the right and left kidneys were highly (R2≥0.90) correlated with gestational age but, in comparison, the thickness of both kidneys was less correlated (R2≤0.86) with gestational age. All of the renal parameters were significantly correlated with the crown-rump length in the early, mid- and late stages of gestation but, the correlation between the thickness of the right kidney and crown-rump length was not significant in the late stage of gestation contrary to the left kidney. Moreover, the correlation between the cranial width of the left kidney and the crown-rump length was also shown to be insignificant.

Conclusion: According to the results of this study, which was based on an anatomical approach to the correlation between organ development and gestational age; kidney measurements can be used as collateral criteria for the prediction of gestational age.