A large variation in the gestation length can be expected when the gestation is calculated
from the day of mating to birth. The present study was designed to assess the influence of different
factors like litter size, breed, parity and age on gestation length in bitches. A total of 89 small sized
bitches of different breeds having different age, parity and body weight, were selected for the study.
The mean age, body weight and parity of the animals included in the present study were 3.00 ±
0.15 years (1 to 8 years), 9.9 ± 0.25 Kg (6 to 15kg) and 1.14 ± 0.10 (0-4th parity) respectively. The
mean gestation lengths observed in different small sized breeds were 60.68 ± 0.55, 59.82 ± 0.54,
60.78 ± 1.74, 58.83 ± 1.35 and 58.17 ± 0.74 in the Pug, Beagle, Dachshund, French Bulldog and
the Spitz, respectively. The mean litter size in the study was 4.34 ± 0.13 with a range of 2-8. The
mean gestational length in animals having ? 3 litter size was 60.83 ± 0.64 days and 59.90 ± 0.43
days in animals having >3 litter size. Age limit of the animals ranged from 1 to 8 years with a mean of
3 ± 0.15 years. The mean gestation length in bitches aged ?3 years was 60.21 ± 0.23 days (n=63)
and this was 60.15 ± 0.3 (n=26) days in bitches in the >3 years group. Mean gestational length
observed in nulliparous bitches was 60.86 ± 0.4 days (n=29), while in multiparous bitches it was
59.90 ± 0.5 days (n=60). From the present investigation it could be concluded that no significant
difference exists in gestational length between different breeds, litter size, age group and parity.