MVSc

The detailed vaginal cytology and serum progesterone levels were studied
in bitches during normal and induced oestrous cycles.
Twelve anoestrus bitches aged 2 to 5 years were randomly allotted to two
equal groups (Group A and Group B). Animals in Group A were initially treated
with a sustained release preparation of leuprolide acetate at a dose rate of 100
ug/kg body weight followed by gonadorelin (synthetic GnRH analogue) at a dose
rate of 3 ug/kg body weight on the first day of induced oestrus. The Group B
animals were administered with diethylstilbestrol at a dose rate of 0.2 mg/kg body
weight orally for nine consecutive days. Six bitches in natural proestrus acted as
controls (Group C).
All animals in Group A, 66.7 per cent animals in Group B exhibited oestrus
at a mean of 12.67 and 15.25 days respectively from the first day of treatment.
There was significant difference in time taken for onset of oestrus between
treatment groups.
The duration of proestral bleeding was 6.67, 8.50 and 8.67 days and
duration of oestrus was 8.0, 7.75 and 8.0 days in Group A, Group B and Group C
respecti vel y.
A conception rate of 83.3, 50 and 83.3 per cent with a mean litter size of
5.6, 6.0 and 5.6 was obtained in Group A, Group B and Group C respectively.

There was significant difference in conception rate between treatment groups,
however, no significant difference in litter size was observed.
The detailed vaginal cytology during normal and induced oestrous cycle
was studied usmg Wright's, Wright-Giemsa's, modified Shorrs and
Papanicolaou's staining and cellular indices like Superficial cell index (SCl),
Eosinophilic index (El) and Kariopyknotic index (KPl) were derived. The SCl
and El values were found to vary between pregnant and non-pregnant animals in
)
all the groups, but no significant variation was observed in KPl values.
Serum progesterone level was estimated during different stages of normal
and induced oestrous cycles. Significantly higher progesterone levels were
observed on the day of second mating in treatment groups (12.63 ng/ml in Group
A and 12.25 ng/ml in Group B) as compared to control group (6.87 ng/ml). Serum
progesterone levels were lower during oestrus and on the tenth day of second
mating in all the non-pregnant animals as compared to pregnant animals.
It is concluded that bitches in anoestrus could be induced to fertile oestrus
using sustained release preparation of leuprolide acetate followed by gonadorelin
with a higher induction and conception rate with normal litter size. Oral treatment
with diethylstilbestrol is less effective for inducing oestrus.