when effects of treatment were judged by 1.0 ng/ml or more increase of serum progesterone levels 10 days after treatment , hcg was effective in 13 of 37 cows ( 35 % ) , retreatment with gn-rh analog was successful in 8 of 16 cows ( 50 % ) and apg was ineffective in 3 cows not responding to both hcg and gn-rh analog .
C0018061
apg
C0018062
hcg