This is consistent with the findings of Mellouk et al [16], who found that Holstein heifers fed a diet of different energy levels during the perinatal period had earlier onset of luteal activity after first calving in cows in the HE group, and the LH pulse frequency was higher than that in the low-energy group, suggesting that higher energy levels may potentially affect the reproductive performance of cows by modulating the secretion of reproductive-related hormones. Here, PLOD1 is linked to hereditary elliptocytosis.