Immunologic response of lambs to emulsified foot-and-mouth disease vaccine

Abstract

Passively-immune lambs which acquired vaccine-induced foot-and-mouth disease antibodies from their mothers' colostrum, resisted infection during the first 30--40 days of life. A more durable active immunity and production of additional virus-neutralizing antibodies occurred in such lambs after vaccination with antigen in oil adjuvant. Susceptible lambs from nonvaccinated mothers were also protected by emulsified vaccine even when vaccinated at 1 day of age.

Association of the time that elapsed from last vaccination with protective effectiveness against foot-and-mouth disease in small ruminants

“…The colostrum pool was obtained from dams vaccinated at least twice with the last vaccine administered between 2.1 and 3.3 months prior to parturition. According to a previous report on lambs ingesting colostrum from dams vaccinated 2 months prior to parturition, the average half-life of maternal FMDV antibodies is 22.4 days post-parturition [ 3 ]. Although the levels of maternal antibodies in the colostrum and lambs during the outbreak were not measured, circumstantial epidemiological evidence and data from previous report [ 3 ] suggest that the high incidence observed in lambs in the described outbreak was due to consumption of colostrum with low levels of anti-FMD antibodies.…”

“…According to a previous report on lambs ingesting colostrum from dams vaccinated 2 months prior to parturition, the average half-life of maternal FMDV antibodies is 22.4 days post-parturition [ 3 ]. Although the levels of maternal antibodies in the colostrum and lambs during the outbreak were not measured, circumstantial epidemiological evidence and data from previous report [ 3 ] suggest that the high incidence observed in lambs in the described outbreak was due to consumption of colostrum with low levels of anti-FMD antibodies. The low antibody levels might have been a result of waning immunity among the dams that caused decreased secretion of anti-FMDV antibodies into the colostrum.…”

Response to foot-and-mouth disease vaccines in newborn calves. Influence of age, colostral antibodies and adjuvants

“…Although Nicholls et al (1985) have shown that, in the absence of CAb 1-week-old calves responded to FMDV vaccination as well as adult cattle, preliminary experiments in our Institute (Sadir, A. M. et (INTA & PIADC, 1977;Rivenson et al 1982). Furthermore, it has been shown that, in other species, vaccination of newborn animals with OE-FMDV vaccines induces immune responses even in the presence of colostral antibody (CAb) (Cunliffe & Graves, 1970;Morgan & McKercher, 1979), although some contradictory evidence has recently appeared (Francis & Black, 1986).…”