Immunité passive colostrale chez les jeunes issus des chèvres et brebis vaccinées avec le vaccin antipeste des petits ruminants

Résumé

To determine the duration of maternal immunity to peste des petits ruminants (RPR) virus and the influence of the pregnancy period on this duration, 1,119 dams (17.5% ewes and 82.5% goats) were vaccinated with anti-RPR vaccine. Serological results showed a total prevalence of 78.4%, with wide variations, ranging from 21.4 to 100% (SD 0.17%) (Table 1). We showed that 88.5% of the young animals born from vaccinated dams had anti-RPR antibodies from 0 to 30 days, 61.3% at 120 days, 40.5% at 150 days and 7.7% at 180 days, indicating that the duration of maternal immunity to RPR ranges from 4 to 5 months (Table 2). Concerning the effect of the pregnancy period when dams are vaccinated on the duration of maternal immunity to RPR, the results showed no difference from 0 to 2 months or after 5 months. However, in young 3-4 month old animals, only 65% of those born from dams vaccinated during the second pregnancy period retained RPR virus antibodies, compared to 80% for dams vaccinated during the first pregnancy period, which thus seems to be the best vaccination period (Table 3).