An experiment was designed to test the effect of the administration of 10 x 10⁶ UI of vit D3, on the seric calcium levels and on the shear force on the longissimus dorsi at 3 and 7 days post-mortem.
A unique intramuscular injection of 10 x 10⁶ UI of vit D3, was administrated to the treated animals at day 8 before slaughter.
Sixty days before slaughter, 80 Hereford cows were randomized to the treatment according to: live weigth, daily weigth gain, body condition and managed under the same grazing condition.
No significant differences between treatments were observed for fat depth at P8 point and daily weigth gain was observed.
At day 3 the W-B shear force were no significant different between treatments.
The treated group showed a lower Warner-Bratzler shear force than the control group at 7 days of maturation (4.55 kg vs. 4.05 kg P < 0.05).
It is concluded that at 7 days of maturation the parenteral administration of 10 x 10⁶ UI of vit. D3 lowered the longissimus dorsi W-B shear force on adults cows.