To Caesar or Not to Caesar ? - that is the Question
By Angus Hayes of Bowral Veterinary Hospital
Every puppy is important.The loss of a puppy can be devastating emotionally, financially and can ruin a carefully planned breeding program. In times gone by, it was accepted that a bitch would lose a few pups every time she whelped. In many cases a lot of these problems could have been avoided with early intervention and management, meaning your bitch was happier and healthier after whelping and her young puppies were in a more vital state of health to take on the world.
Abnormalities in the normal whelping process are termed dystocia and often Caesarian surgery needs to be performed when the bitch or the puppies are at risk.
What is normal and how to recognise the abnormal
Every whelping is different and the "normal" signs will vary markedly between different dogs. To recognise what is abnormal, a review of the typical stages of whelping is useful. At Bowral Veterinary Hospital, we find that if you can identify problems early, then they can either be rectified or the decision can be made to progress to Caesarian surgery.
Most bitches will drop their core body temperature one degree Celsius 8-24 hours before whelping. Taking daily temperature checks towards the end of gestation is a useful but not 100% accurate way of timing this. Stage One labour begins with the onset of rhythmic contractions of the uterus. These are usually not visible externally and your bitch may start nesting, be restless, lose interest in food or vomit. The stage is complete once the cervix has completely opened. A digital vaginal exam will not be able to feel the cervix, however you may feel the vagina softening in the last few days as the hormone relaxin begins to take effect. Some bitches may show no external signs of Stage One labour. Stage One labour averages 6-12 hours but may last up to 24 hours.
Stage Two labour begins with the full dilation of the cervix and expulsion of the first puppy from the uterus. If you can see visible straining or contractions and fetal fluid has passed from the vagina, then the bitch has started Stage Two labour. In a normal labour, the bitch may show weak infrequent straining for up to two hours before giving birth to the first pup. If the bitch is showing strong frequent and non productive straining for more than 20-30 minutes with no sign of a puppy, veterinary advice should be sought. A dark green vaginal discharge is fluid from the placenta and if present for more than 20-30 minutes without a puppy, indicates signs of dystocia.
Stage Three labour involves the expulsion of the membranes and usually occurs within 15 minutes of the delivery of each pup. The bitch will cycle between Stage Two and Three in a normal whelp until all the pups are born. In some cases however, two or three pups may be born before the passage of the placentas. The total number of placentas should equal the total number of puppies. Close attention should be paid to the bitch as she may eat one or more of the placentas which need to be counted. She will often vomit them later and it is not necessary for the bitch to eat the placentae.
It is possible for a bitch to pause between puppies for 1-2 hours. In bitches that have had previous problems, a higher level of suspicion should be maintained rather than thinking she is just "taking a rest". If the bitch is showing any signs of pain, contractions, shivering, ataxia (wobbly legs) or dark vaginal discharge, a veterinarian should be contacted immediately for advice.
Most cases of dystocia (approximately 75%) are maternal in origin, with the other 25% being fetal. The most common cause of dystocia is uterine inertia. This may be due to conditions such as single pup syndrome, or because of over stretching of the uterus due to factors such as large litters. Other issues such as underlying metabolic disease, an inherited predisposition or age related changes may contribute to primary uterine inertia. In these cases, an elective caesarian may provide a way to keep the bitch and puppies alive.
In some cases of primary inertia in a bright, alert and healthy bitch, active exercising for 10-15 minutes may help induce the labour. The bitch should be provided with fluids and energy (honey or glucose) by mouth to avoid dehydration and hypoglycaemia during labour. In nervous bitches, gentle reassurance may help reduce the voluntary inhibition of labour.
In secondary inertia, the muscles in the uterus are exhausted and unable to continue the contractions to expel the puppies. If puppies are not born within the time limits mentioned above, or you have noticed successive weaker contractions and prolonged time between puppies, secondary uterine inertia is likely to have occurred. This is especially the case in larger litters. Medical interventions such as oxytocin at the veterinary hospital and procedures at home such as exercising the bitch are unlikely to have any effect on secondary uterine inertia. In these cases, Caesarian surgery is required.
Other causes of dystocia such as uterine rupture or torsion (twisting) are a surgical emergency and the bitch should be taken to a vet immediately. In these cases, the bitch will often be showing signs of pain such as shivering, reluctance to move and abdominal pain on palpation.
Fetal obstruction normally occurs in the pelvic canal and may be more common in certain breeds (such as Boston Terriers) with larger sized heads relative to the pelvic canal. Similarly, cross breeds or accidental matings with a larger breed dog can result in larger puppies that may not pass. Manipulation of the pup should be extremely gentle and generally most of these cases need to progress to Caesarian immediately.
Metabolic disease such as hypocalcaemia (milk fever) are life threatening for the bitch and puppies. In early stages, the signs may be as simple as progressively weaker and slower contractions. In more severe cases the bitch may show uncontrollable shivering or ataxia (wobbly legs) progressing to cardiac arrest.
Planning an elective caesarian
In bitches that have needed a caesarian before or have known potential for problems (eg oversize puppies) an elective caesarian may be planned. The timing is extremely important as we don't want to deliver underdeveloped puppies.
Multiple mating dates give a poor indication of correct whelping or optimum Caesarian dates. This is because the bitch may ovulate at varying times relative to when she accepts the male. Progesterone tests when the bitch is in season will help calculate the correct pregnancy dates. If this has not occurred, progesterone tests and ultrasound close to whelping may assist in determining the correct time for surgery. At our hospital, we find early planning will greatly help in determining the best time for surgery to enhance the welfare of the bitch and puppies.
With early recognition of problems, your bitch and puppies are in a much better position to tackle a stressful time for them all. Every puppy is important and outcomes are much better when everyone is in readiness and aware of what to look for when problems arise.
Nature is generally fairly good at getting it right, however we must be prepared to intervene when required.