Lipid deposition in different fiber types of skeletal muscle of periparturient dairy cows.

The intracellular deposition of neutral lipid in skeletal muscle of dairy cows before and after calving has been studied in biopsy samples taken from 72 cows in three herds. The amounts of neutral lipid in individual fibers were estimated using Oil red O-stained sections and an average value was calculated for each fiber type within a sample. Intracellular lipid deposition occurred mainly in type 1 fibers and reached its highest level one week after calving. The amount of lipid in muscle at this time showed a high correlation with the amount of lipid in liver and with the rate of lipid mobilization from tissue reserves.