The objective of this study was to examine whether the plane of nutrition of cows at a critical time for fetal
skeletal muscle and adipose tissue development would affect meat quality and carcass composition of
offspring. To alter maternal nutrition, beef cows were placed on improved pasture (IP) or native range (NR)
pasture from 120 to 150 through 180 to 210 days of gestation. Esophageal extrusa samples collected from cows
grazing IP varied from 11.1% crude protein of organic matter early in the test period to 6.0% crude protein of
organic matter at the end of the grazing period; whereas, extrusa samples of cows grazing NR ranged from 6.5%
crude protein of organic matter during early grazing to 5.4% crude protein of organic matter at the end of the
grazing period. Steers were slaughtered and carcass characteristics were collected. Warner–Bratzler shear
force was performed on longissumus steaks, western blotting was used to measure proteolysis, and myosin
isoform typing was performed. Improved pasture steers had heavier live and hot carcass weights. Tenderness
was greater in IP compared to NR steers. No difference in calpastatin content and troponin-T degradation was
observed between treatments. The 12th rib fat thickness was greater for IP than for NR steers. Subcutaneous
adipose tissue of IP steers tended to have a greater number of cells per field of view than NR steers. Data show
improving nutritional status of cows during mid to late gestation affects tenderness, adipose tissue deposition
and growth in steers