Perinatal Mortality in Kittens


Dr Rob Foster


Perinatal mortality in kittens is not studied so information is limited. Kitten mortality is reported to be about 9.1% in the first 8 weeks, with no detailed figures for the first 48hrs postpartum. Most of the 9.1% are in the first week.


Non infectious



Osteogenesis imperfecta

Neonatal Isoerythrolysis.

Isoerythrolysis is a rare disease that occurs when toms with type A or AB blood are mated to queens with Type B blood. Feline blood groups are simple - there is Type A (dominant), Type B (recessive) and rarely AB. Tyep Mik is also now recognised. Queens with type B blood develop antibody to the A antigen and pass this antigen in colostrum. Neonates with type A or AB blood will hemolyse. Cats with type A blood have anti B antibody, but it is weak.

Affected kittens are weak and have haemoglobinuria. They die in the first week of life.

Silvestre-Ferreira AC, Pastor J. Feline neonatal isoerythrolysis and the importance of feline blood types. Vet Med Int. 2010; 2010: 753726. doi: 10.4061/2010/753726.





The disease is caused by bacteria in kittens can be grouped into those that are caught occur more commonly or those that are rare. We begin with those that are more common.


S. canis (group G) in cats is very common in the vagina of cats both from local vet clinics and in a research colony. First time queens remained colonized right up to parturition with higher numbers than older queens who seemed  to clear a week or more before and first time queens recolonized sooner. So exposure was the issue. The kittens had antibodies from milk but they antibodies plummeted just before they died. The umbilical vein was infected extending to liver and sepsis. (Pat Blanchard pers comm)


Bacterial pneumonia occurs periodically in kittens and is one of the many causes of fading kitten syndrome. Gram-negative bacteria predominates and Highland et al (2009) reported on three kittens with E. coli pneumonia. These kittens had haemorrhagic or bloody fibrin OC's thoracic fluid and pulmonary consolidation. The pneumonia was necrotising and haemorrhagic with pleuritis.

Streptococcus canis

Escherishia coli

E coli are known for indicing septicemia and pneumonia in new born kittens.These may be intestinal or extraintestinal organisms.


Margaret A. Highland,1 Barbara A. Byrne, Chitrita DebRoy, Eileen M. Samitz, Tracy S. Peterson, Karen L. Oslund. (2009) Extraintestinal pathogenic Escherichia coli–induced pneumonia in three kittens and fecal prevalence in a clinically healthy cohort population. JVDI 2009 21: 609-615






Toxoplasma gondii

Phylum Apicomplexa, Class Conoidasida, Order Eucoccidiorida, Family Sarcocystidae, Genus Toxoplasma, Species Toxoplasma gondii


Toxoplasma gondii is a cause of perinatal and neonatal mortality. Dubey et al (1996) found that after experimental infection of 5 pregnant queens, the most consistent lesions were interstitial pneumonia; necrotizing hepatitis; myocarditis; skeletal myositis; glossal myositis; encephalitis affecting the cerebrum, brain stem, and spinal cord; uveitis; necrotizing adrenal adenitis; and interstitial nephritis.



Dubey JP, Mattix ME, Lipscomb TP. Lesions of neonatally induced toxoplasmosis in cats. Vet Pathol. 1996; 33: 290-295.

Dubey JP. Toxoplasmosis. J Am Vet Med Assoc. 1994; 205: 1593-1598.

(JAVMA 203: 1550, 207: 179)
neonatal jaundice and inc. Alkphos
queen Ab +ve


Alphacoronavirus 1 (Feline coronavirus strains including Feline infectious peritonitis virus)

Felid alphaherpesvirus 1 (FHV-1)

Carnivore protoparvovirus 1 (Feline panleukopenia virus; FPLV)


Highland MA, Byrne BA, Debroy C, Samitz EM, Peterson TS, Oslund KL. (2009). Extraintestinal pathogenic Escherichia coli-induced pneumonia in three kittens and fecal prevalence in a clinically healthy cohort population. J Vet Diagn Invest 2009; 21(5): 609-615.

Sparkes AH, Rogers K, Henley WE, Gunn-Moore DA, May JM, Gruffydd-Jones TJ, Bessant C. (2006) A questionnaire-based study of gestation, parturition and neonatal mortality in pedigree breeding cats in the UK. J Feline Med Surg 2006; 8: 145-157