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

Dairy cows experiencing heat stress (HS) during the precalving 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.

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.

Carryover effects of maternal late-gestation heat stress on granddaughters' growth and mammary gland development.

Maternal (F) exposure to late-gestation heat stress reduces their daughter's (F) mammary gland fat pad (FP) mass, parenchyma (PAR) mass, and epithelial cell proliferation when evaluated at birth and weaning, and the daughters go on to produce less milk in their first lactation. Herein, we investigated the effect of maternal late-gestation heat stress on whole-body growth and mammary development of their granddaughters (F). Multiparous F cows had access to heat abatement (n = 41, shade, and active cooling via fans and water soakers) or not (n = 41, shade only) for the last 56 d of gestation during a subtropical summer.