
I have used in on 6 generations of bitches and my litters have averaged out at 6 pups (3 - 9 live pups) per litter which is in line with the breed average, so no I have had no ill effects in pregnancy.
the main effect I have noticed is that with successive generations pups have been heavier at birth than average. My adults are still the same as adults in size.
A bitch will seem flatter (no longer the pregnant Pygmy goat look) at the sides as the belly drops after 6 weeks.