Reproduction plays a pivotal role in dairy production. Treatments enhancing or accelerating uterine involution may increase reproductive efficiency.

Glucose requirements during early lactation are usually not satisfied by some diets for high-producing dairy cows. Therefore, feeding rumen-protected glucose (RPG) is becoming an alternative strategy to increase glucose and energy supply for dairy cows.

Recently, researchers from the Institute of Subtropical Agriculture (ISA) of the Chinese Academy of Sciences and Hunan Agricultural University found that rumen-protected glucose may benefit uterine involution of early postpartum dairy cows.

The researchers fed the dairy cows with 0 or 200 g rumen-protected glucose twice every day from -7 ± 2 to 14 d to illustrate the effect of RPG on the uterine involution during the early post-natal period.

They found that the positive cells of PCNA and Ki67 were increased in the uterus of RPG group compared with the control group. The RPG addition increased the plasma IGF1 level 14 d after delivery.

The mRNA expressions of the IGF family members were upregulated, and mRNA expressions of matrix metalloproteinase MMP3 and MMP9 were downregulated in cows from the RPG group compared with the control group.

Furthermore, the RPG supplementation increased the protein expressions of phosphorylated (p)-AKT to total AKT and p-mTOR to total mTOR ratios in the uterus.

The results indicated that dietary RPG addition promoted the proliferation of endometrial cells in postpartum dairy cows by stimulating the insulin-like growth factor system and mTOR pathway, and might be beneficial for uterine recovery.

The study, published in Animals, was supported by the National Key Research and Development Program of China, Major Project of Hunan Province, and CAS Science and Technology Service Network Initiative.