Protection against canine parvovirus type 2 infection in puppies by colostrum-derived antibodies
During the first weeks of life puppies remain protected against canine parvovirus type 2 (CPV2) infection thanks to maternally derived antibodies (MDA) absorbed with colostrum after birth. The objective of the present study was to present the variability in CPV2-specific passive immune transfer and its consequences in puppies naturally exposed to the parvovirus. Seventy-nine puppies from one breeding kennel were included in the study at birth and followed until 56 d of age. Once per week the MDA titre for CPV2 specific antibodies was determined in blood. Viral excretion was also evaluated on a rectal swab by CPV2 PCR assay and puppies were weighed to determine growth rate. At 2 d of age, thirty-four out of seventy-nine puppies (43 %) had MDA ≤1:160 (designed group A) and forty-five puppies (57 %) had greater MDA titres (designed group B). The level of absorbed maternal antibodies was shown to be associated with breed size and growth rate during the first 48 h of life. The MDA level declined with age in all cases; however, the proportion of puppies with the antibody level considered as protective against CPV2 infection was significantly higher in group B compared with A from day 2 until 42. Among all puppies surviving until 56 d of age, sixty-seven out of seventy (95·7 %) underwent CPV2 infection. However, puppies from group A excreted CPV2 significantly earlier than puppies from group B. The present study demonstrates the link between passive immune transfer, in terms of level of specific MDA absorbed, and length of the protection period against parvovirus infection in weaning puppies.