How maternal parvovirus antibodies protect newborn puppies

Abstract

BACKGROUND: Passive immunity (mainly IgG) protects canine neonates from the highly pathogenic and contagious canine parvovirus, while it can also largely interfere with parvovirus early vaccinations. OBJECTIVES: Quantitative evaluation of the anti-parvovirus IgG transferred to newborn puppies from immunised bitches during the neonatal period, as the influence of individual variations on the kinetics of the specific IgG was also estimated. METHODS: Sera samples from 80 new born puppies were taken at 10 day intervals in a dog kennel and quantitatively assessed for specific anti-parvovirus IgG with a commercial ELISA kit. The resultant data were subjected to specific statistical analysis. RESULTS: Statistical analysis definitely showed that the anti-parvovirus IgG sufficiently transferred from the vaccinated bitches to their offspring, so that the average titre calculated was 5675.5 and 2625.9 in the 10 and 20 day old puppies, respectively, which were both considered significantly higher than the protective threshold titre (810). In our setting, however, the average anti-parvovirus IgG titre of the one-month old puppies was not significantly estimated protective, 959.7 (median = 15.57) with a coefficient of variation of 148.6%. It was also estimated that factors including bitches' age, litters' diversity, puppies' age, the period from parvovirus vaccination to parturition and litter size reduced the passive anti-parvovirus IgG levels in the newborn puppies, while bitches' parity evaluated as a positive factor to boost passive anti-parvovirus IgG titre. CONCLUSIONS: These results raise our knowledge on the kinetics of passive anti-parvovirus IgG in newborn puppies and are useful for establishing parvovirus vaccination schedules.