By Nicole Mackie
To ensure a plump, happy litter of pups
the bitch must also be happy and healthy
THE length of pregnancy (gestation) in the bitch may vary between 56 and 72 days since both early and late matings may be fertile.
Early matings require the survival of sperm with the female until ovulation and can therefore produce a longer pregnancy. Late matings are when the eggs are fertilised some time after ovulation, which can produce a shorter pregnancy. Make sure your bitch is up-to-date with her vaccinations well before the intended mating, as this will pass on passive immunity to the puppies.
Signs of pregnancy
- Abdominal enlargement - but this may not be obvious if the number of pups is small.
- Reduced food intake about a month in to pregnancy. At this time the bitch may need to be fed little but often.
- Vaginal discharge
- Enlargement and reddening of mammary glands (this sign can also be present in a pseudo-pregnancy).
- Milk production can appear at any time from day 55 right up until parturition.
Increased food intake is not necessary in the first 30 days of pregnancy. Over-feeding at this time may lead to unwanted fat and problems during whelping. After this time the bitch's requirement for carbohydrate and protein increases. During the last month of pregnancy most of the foetal weight gain occurs and food consumption will increase considerably. The bitch's food intake should increase gradually, so that at the time of whelping she is eating about 60 percent more than at the time of mating.
Provided the diet is well balanced and contains all the vitamins and minerals necessary, there is no need to supplement the diet. However, with a large litter and enlarged abdomen she may find it difficult to consume a large bowl of food. You may have to divide her food into three or four meals during the day.
Your bitch can continue with normal regular daily exercise throughout the pregnancy, limited only by her own willingness.
It is necessary to worm your bitch during pregnancy. Speak to your local veterinarian about the best form of worm medication and the best time to worm her for the benefit of both herself and the pups.
Palpation can be performed by your veterinarian approximately one month after mating but is difficult after 35 days. This technique is very accurate but can be difficult in obese or nervous animals. In late pregnancy it is possible to hear the foetal heart beats using a stethoscope, or read a foetal ECG.
Foetal heart rate is more rapid than the bitch's. Pregnancy diagnosis by radiograph is possible after day 45 when the foetal skeleton is detectable and the heads can be counted.
Although it is unlikely there will be radiation damage to the foetus at this stage, anaesthesia of the dam may be a risk to the pups. Ultrasound is commonly used to diagnose pregnancy. The procedure is safe and without risk to the dam, pups or veterinarian. The bitch can be examined standing with little restraint. With ultrasound it is possible to diagnose the pregnancy from 16 days after ovulation, but it is best to wait about 28 days after mating. It is possible to assess the number of pups but can be inaccurate if the litter size is large. It is possible to examine the bitch any time after 28 days to diagnose pregnancy.
Nicole is a qualified veterinary nurse and breeds Labrador retrievers. She will be talking about whelping and post-natal care in future issues.