Death usually occurs within the first five days of life, but can occur up to ten weeks of age. Responsible for approximately 50% of newborn puppy deaths. About 30% of pedigree puppies die in their first few weeks of life, and only about half of them die from identifiable causes. Premature or sudden death in puppies is generally known as fading puppy syndrome.
Death is usually preceded by few or very brief signs of illness. This is most common in the first week of life, but can occur up to 3 weeks of life. A number of different conditions can cause fading puppy syndrome. Sometimes solitary puppy deaths are related to a birth defect that wasn't immediately evident.
Sometimes the mother does not care for the weaker or smaller members of the litter. Young puppies have an underdeveloped immune system. They acquire antibodies from the milk produced by the mother dog directly after birth, called colostrum. Puppies that don't breastfeed properly won't receive these antibodies and are much more likely to get a serious infection.
Sometimes, a breast infection (mastitis) or calcium deficiency in the mother can limit her milk supply. Canine herpesvirus is another common cause of fading puppy syndrome. This virus can be transmitted from the mother in utero or from infected fluids after birth. It is usually not symptomatic in adults, but causes death in puppies up to about 3 weeks of age.
If the mother has the virus, puppies may be born weak to begin with, or even be born dead. If a puppy is born with a compromised immune system, it will usually die within the first five days of life. However, puppies are still at high risk for the first three weeks, which is when they are most likely to develop fading puppy syndrome. Newborn puppies are born with an immature immune system that needs to develop over time, starting with breast milk.
Because of their immature organs and body systems, puppies are prone to various aggressions, including infections and environmental, nutritional and metabolic factors. In addition, young animals do not yet have strong body temperature regulation, and their body temperature can fluctuate profoundly in response to changes in ambient temperature and humidity. Glucose control can also be poor and blood glucose levels can fall below normal ranges in cases of nutritional disorders, leading to a state of hypoglycemia. Neonatal mortality, or fainting syndrome, involves the death of puppies from birth to two weeks of age.
This syndrome is more common in pedigree puppies. Puppies that die soon after birth are often referred to as “puppies that wither”. There may be a known cause, but approximately 55% of puppies lost to this condition have no identifiable cause, so knowing if a newborn puppy is dying isn't always easy. There are four main causes of death for newborn puppies.
Like other animals that have multiple births, it is not unusual for dogs to give birth to puppies that are born stillborn or that have puppies that die soon after birth. If you currently have newborn puppies to care for, they need to receive colostrum from the mother dog within their first 12 hours of life. This is part of the reason small puppies need to be close to their mother and littermates; they are a source of heat. Unfortunately, normal losses before weaning can reach 30%, and about half of these losses occur within the first week of life of puppies.
If it is infectious, it may be a cause for concern because an infection can spread to other puppies in the litter. While a litter of puppies will generally look the same while they are born, within a few days you will likely notice larger and smaller puppies. Most of the time, puppies that wither rapidly progress to loss of muscle tone, severe lethargy, and death. It is used to describe neonatal puppies that are born healthy, but that gradually wither and die from unknown and uncontrollable causes.
Puppies that die from this syndrome are healthy and normal at birth, but they wither and die within one to three weeks. It usually affects puppies within the first three weeks of life, but they may suffer similar problems until they are 10 weeks old. For the first two weeks of your litter's life, puppies are vulnerable to disease and stress, as they are unable to regulate their bodies on their own. Nutrients in breast milk help build puppies' immune systems, but abnormal discharge from the teats or infection of the mammary glands in the mother can prevent puppies from developing immunity.