Abstract
A calcium preparation (Ca) was injected into the cow i.v. two days after a parturition and mainly uterine involution was investigated by an ultrasonic image. 23 Holstein cows in the F and M meadows with different breeding conditions were used in this test. The experiment group, six cows in the F meadow (F) and nine cows in the M meadoe (M) was injected with a Ca and a control group was done with glucose. 1) The time to dispose of the lochia in the uterine horns was 24.8 and 32.8 days in the F meadow, and 25.1 and 38.0 days in the M on the average, respectively. 2 ) The time until the shape of the uterine horns was judged to be recovered was 19.5 and 20.5 days on the average in the F meadow, and 15.1 and 22.5 days in the M meadow. The time until elasticity was judged to be recovered was 20.3 and 19.8 days on the average in the F meadow, and 15.3 and 22.5 days in the M meadow. 3 ) The uterine involution time in the ultrasonic image was 35.5 and 41.5 days in the F meadow, and 30.1 and 44.0 days in the M meadow, on the average. 4 ) The average time required until the first postpartum ovulation occurred was 34.0 and 40.8 days respectively in the F meadow and 24.2 and 47.5 days in the M meadow. These results suggest that the intravenous injection with a Ca preparation immediately after the parturition might have an effect to shorten the time required for uterine involution and first ovulation.
