Pregnancy: 0 to day 42

Gestating Bitch

Gestation begins when the female’s ova are fertilised by the male spermatozoa.
This fertilisation gives rise to a fertilised egg of which half of the genetic heritage stems from the father’s chromosomes and half from the mother’s chromosomes.
This egg is the first component of a new living being, first of all an embryo until the 35th day of gestation and then a foetus and future puppy in the final third of gestation.

The first week of her pregnancy

The embryos are afloat in the uterus

Towards the end of the first week following fertilisation, the embryos, which are formed very high up in the uterus, will migrate towards the uterine horns.
They then float and move around within the uterine liquid.

Practical tips
At the end of her heat, you can groom your bitch as usual. This will not put the embryos at risk.
At the beginning of pregnancy, your bitch may go off her food a little, this is quite normal.
At any stage of the pregnancy, don’t give your bitch any medication without checking with your vet first.


At around day 16 of gestation, the embryos become embedded in the uterus where they will develop, in a process called nidation.
Each individual embryo is then progressively enveloped in its own foetal sac which will provide it with all of the necessary nutrients until birth.

Diagnosing pregnancy
As soon as you think your bitch might be pregnant, make an appointment with your vet to confirm the diagnosis by abdominal palpation or a blood test.
Getting an early confirmation means you can monitor your bitch’s progress and condition throughout her gestation.
From day 25, an ultrasound scan can give you an idea as to the size of the litter and will also detect any possible anomalies.

Feeding your bitch

During the initial phase of gestation, from mating until day 42, the goal is to maintain your bitch’s ideal weight.
Her energy requirements remain stable, the embryos do not develop greatly and no nutritional change is required.
Keep your bitch on a Health Nutrition diet which will provide her with high quality nutrients.

Monitoring her weight
You must weigh your bitch regularly.
Early weight gain can have very damaging effects on her health: fat stored in the muscle can hinder the intense muscular effort required at whelping, thus causing complications.

During the initial phase of gestation, up until day 42, your bitch's weight gain must not exceed 10% of her ideal weight

No calcium supplements !

No vitamin or mineral supplements are required during gestation if the bitch has an appropriate, balanced food.
Giving her calcium in particular can cause serious neurological disorders.
If your vet considers it necessary, he will prescribe a supplement - but this is most unlikely, and only to be followed on veterinary advice.

The unborn puppies...

By day 35, the embryos become foetuses - their eyelids have appeared, their ears have formed, the toes have separated and all their organs have begun to develop.

Week 6 : the turning point

From day 42, the pace changes! Your bitch is entering the final third of gestation.
The foetuses are developing fast, their skeletons, which started out as cartilage, now mineralise and solidify, and they gain weight!
An amazing three quarters of growth prior to birth occurs in this final third of gestation.

The mother's requirements change
From the 6th week of pregnancy, the bitch's energy, mineral and protein requirements rise significantly in line with her puppies' rapid growth and in preparation for lactation.
At the same time her appetite and digestive abilities decline, particularly due to the increased volume of the uterus.
She therefore needs a balanced diet with a high nutritional value and a very high energy content.

Energy supplies from week 6 = + 10 % per week

From day 35, your bitch needs a different diet , how can you do this?

The change in diet must be gradual, taking place over a week to make sure that your bitch doesn’t suffer any digestive disorders. Start by mixing the new food with her usual diet and increase the amount a little every day. On day 3, mix half and half and then progressively reduce the former diet so that by the end of the week she will be eating just the new food. By day 42, the transition will be complete.

Did you

At the end of pregnancy, the bitch's maximum weight gain =
+ 30 % of ideal weight (Mini or Medium sizes)
+ 25 % of ideal weight (Maxi or Giant sizes)

The unborn puppies!

The claws appear at around day 40, and then the coat forms and the skeleton ossifies.

During this period, the puppies gain 75% of their birth weight

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