Abstract
The present study was carried out to investigate the estrous behavior and vaginal smear after induction of estrus with exogenous hormones in the premature, metestrous and anestrous bitches. A total of 21 bitches(Mixed breed: 16, Jindo breed: 5), from 10 months to 5 years of age and weighing 8 to 15 kg was studied the change of vaginal smear and the estrous behavior before and after induction of estrus. The results obtained are as follows: 1. In the treatment A(They were given the $PGF_2{\alpha}$, estrone, estradiol-$17{\beta}$, PMSG and HCG) proestrus commenced in $10.16{\pm}1.44$($Mean{\pm}SEM$) days after treatment, The mean duration of proestrus, and estrus was $7.50{\pm}1.44$ and $13.50{\pm}3.44$ days, respectively. In the treatment B(They were given the PMSG and HCG) proestrus commenced in $5.53{\pm}0.59$ days after treatment. The mean duration of proestrus and estrus was $6.60{\pm}0.71$ and $14.60{\pm}1.14$ days, respectively. 2. All of the 6 bitches in the treatment A showed vulval swelling and vaginal discharge, 14 of the 15 bitches in the treatment B showed vulval swelling and vaginal discharge. However, all of the treatment A and B showed male acceptance. 3. The main change of vaginal smear in proestrus and estrus after induction of estrus was a increase in the proportion of anuclear and superficial cells associated with a decrease in small intermediate and parabasal cells. By the estrous behavior and vaginal smear the estrus was induced in all the premature, metestrous and anestrous bitches.