These are given intramuscularly one month before the due date of parturition and
parturition occurs between 4-26 days. Not good method; wider
range of time is the disadvantage. Here the incidence of RFM is
less. High incidence of calf mortality 45-70% due to premature
placental separation and uterine inertia. Calf died in uterus and
born autolysed. Calf lacks the immunoglobulins. Calf is week and
cannot ingest adequate amount of colostrum.
Short Acting Corticosteroids:
Efficacy is 80-100%. Give intramuscularly two weeks before due date, parturition
may occur within 24-72 hours with an average of 48 hours. Amount of IGs is normal in clostrum. It increases the incidence of
retained placenta which is
related to degree of prematurity. Incidence range is 30-100%.
of prostaglandin is similar to corticosteroids short acting. Its
efficacy is similar to short acting corticosteroids. So no advantage
of estrogen is considered as old method (before the availability of
PGF2α). Disadvantage is poor efficacy and high incidence of
retention of fetal membrane.
Combination of Short Acting Corticosteroids + Estrogen:
It does not
decrease the incidence of retained placenta. However larger doses of estrogen
decrease the interval of parturition by several hours. Chances of
failure are lower.
Acting + Short Acting/ PGF2α:
After administration of 7-12 days of long acting, the short acting
PGF2α is given then at 2-3 days parturition occurs. Interval is
short and predictable however incidence of calf mortality is high.
Corticosteroids and PGF2α not decreases percentage of retained
placenta but chances of failure are decreased.