Correlation between weight, length and fetal membranes of rock cavies (Kerodon rupestris Wied, 1820)

Abstract

We evaluated the correlation between different fetal membranes of rock cavies and determined the relationship between fetal weight and placental weight, the relationship between fetal weight and length of the umbilical cord and the relationship between fetal weight and length of the fetus. The fetuses and fetal membranes of three, five and six females respectively in the first third, middle and late gestation were used, obtained from Multiplication Center for Wild Animals of the Federal University Rural of Semiarid (CEMAS-UFERSA). The data were expressed as mean ± standard deviation, minimum and maximum values, evaluated by the statistical program GraphPad Prism version 6.0. After analysis of parametric assumptions, the data were subjected to Kruskal-Wallis' test and Mann-Whitney's test and linear regression. The relationship between fetal weight and placental weight showed the expression y = 33.73 + 16.38x with an estimate of the coefficient of correlation between fetal weight and placental weight high and positive, showing dependence between variables (R² = 0.7251). The relationship between fetal weight and length of the umbilical cord showed expression y = 35.64 + 25.64x and the correlation analysis between variables, positive (R² = 0.7201) indicating high dependence between variables. Regarding the relationship between fetal weight and length of the fetus, we identified a relationship of the type y = a + bx, whose expression was defined y = 1.26 + 0.41x, with correlation analysis of the variables showing high correlation considering the value of R² = 0.7890. The variables analyzed demonstrate a direct influence on embryonic and fetal development in rock cavies confirming the correlation of these with the size of the fetus.