Uterine activity after ovariectomy in the camel (Camelus dromedarius): effect of exogenous administration of oestrogen and progesterone.

During oestrous cycles of the camel, spontaneous uterine contractions were correlated significantly with plasma oestradiol-17 beta concentration. Ovariectomy in the camel resulted in a decreased plasma concentration of oestradiol-17 beta (< 15 pg ml-1) and progesterone (< 0.1 ng ml-1) and caused complete cessation of uterine activity. Daily administration of oestradiol benzoate (5 mg, intramuscularly) increased the plasma concentration of oestradiol-17 beta (> 45 pg ml-1) and increased the frequency and amplitude of uterine activity. Coadministration of progesterone (100 mg, intramuscularly) increased the plasma concentration of progesterone (> 4 ng ml-1) and increased the frequency but not amplitude of uterine activity. It is suggested that uterine activity in the camel is correlated with the circulating levels of oestradiol-17 beta and progesterone.