Rumen-protected methionine supplementation during the transition period under artificially induced heat stress: impacts on cow-calf performance.

Dairy cows experiencing heat stress (HS) during the pre-calving portion of the transition period give birth to smaller calves and produce less milk and milk protein. Supplementation of rumen-protected methionine (RPM) has been shown to modulate protein, energy, and placenta metabolism, making it a potential candidate to ameliorate HS effects. We investigated the effects of supplementing RPM to transition cows under HS induced by electric heat blanket (EHB) on cow-calf performance.