Pet Factsheets

Fading kitten syndrome

Kittens that fail to thrive and die soon after birth are often known as fading kittens. The kittens may appear normal at birth but may have a disease that has not yet become apparent. Alternatively, they may develop a condition or contract a disease soon after birth. Unfortunately, it is a common problem and deaths due to fading kitten syndrome in the first 12 weeks may range from 5 to 25%. Of the pedigrees, Persians seem to have the highest kitten mortality rate.

What is fading kitten syndrome?

The definition of fading kitten syndrome varies. Sometimes it only includes kittens less than 2 weeks old. However, it can include kittens up to 12 weeks.

Most deaths occur during the first week after birth. Very early death may occur due to neonatal isoerythrolysis in specific situations. Deaths in the first 2 weeks are usually associated with genetic problems or problems acquired in utero or during birth. Deaths after weaning are often associated with infections, usually viruses, while infections in the first few weeks may be viral, or bacterial (often secondary).

How will I know my kitten has fading kitten syndrome?

The kitten will fail to gain weight and may show depression and not be active. It may cry excessively until too weak to do so. It may not take milk, be neglected by the mother, and lie separately to the rest of the litter.

Affected kittens usually steadily deteriorate and die within 2 days of their food intake failing. Kittens from their mother's first litters have much poorer chance of survival. Survival rate then rises until the fourth litter and then tends to decrease again.

What causes fading kitten syndrome?

There are various causes including:

  • Poor maternal nutrition, during pregnancy as well as during lactation, poor maternal immunity and poor transfer of maternal immunity
  • Low birth weight (less than 75 g)
  • Problems with the queen, eg poor milk production, mastitis, other illness
  • Fleas, worms and other parasites
  • Congenital abnormalities (eg, cleft palate, atresia ani, flat chest or “swimmer” kittens, umbilical hernia)
  • Lack of oxygen during birth - especially during long labours
  • A condition known as neonatal isoerythrolysis caused by incompatibility between the mother and the kitten’s blood type (see Feline blood types and blood incompatibilities Owner Factsheet)
  • Viruses, particularly feline panleukopenia, feline infectious peritonitis, and feline herpes virus-1
  • Bacteria (usually secondary, Bordetella can be a primary respiratory infection, salmonella and campylobacter can cause sepsis, bacteria from the skin can cause umbilical infection)
  • Main non-specific factors are lack of oxygen, hypothermia, dehydration and low blood sugar.

How can I prevent fading kitten syndrome occurring?

The breeding queens should be in good health, free of parasites, and vaccinated. Avoid overcrowding and breeding from queens with poor mothering instincts or those that have had a prolonged labour in previous births. Ensure the queen and tom have compatible blood types.

Encourage early bonding and make sure than colostrum (the mother’s first milk) is the first feed as this provides antibodies and transfer of immunity.

The kittens should be kept at a constant, warm temperature and monitored carefully, including being  weighed daily in the first 1-2 weeks. Good hygiene must be maintained and over-crowding (eg multiple queens with coinciding litters) should be avoided. The kittens should not be handled excessively so as not to stress the queen.

Feed a balanced diet at weaning and investigate any sign of illness or any lack of weight gain promptly.

How will my vet treat my kitten?

Your vet will check kittens for congenital problems and signs suggesting specific infections requiring treatment. Your vet may recommend that the kittens be taken into the hospital and fed with an oro-gastric tube that is placed for each feed. Older kittens may have a feeding tube placed in the esophagus (gullet), fitted under anaesthetic. Oxygen therapy may be given along with fluid therapy, antibiotics, and colostrum (mother’s first milk). Temperature and bodyweight will be monitored until the kitten is bright, eating and gaining weight.

Will a fading kitten survive?

Unfortunately, despite early and aggressive treatment, kittens are unlikely to survive. Deterioration may be rapid.