[Udder immunization for the protection of calves against salmonella infections. 1. Detection of specific Ig classes in the mother, colostrum and calf and the course of infection].

Pregnant cows were vaccinated at ablactation by infusion of heat inactivated S. dublin or S. typhimurium into the mammary gland in order to protect their offsprings via colostrum against salmonellosis. This method of vaccination is based upon statements according to which specific IgA and IgM play a prominent role in respect of protection. Both Ig classes are produced locally and are not channelled from the mother's system into the mammary gland. In comparison to calves from non-vaccinated control animals, calves from vaccinated cows did not exhibit clinical symptoms after challenge infection, and had a reduced salmonella excretion rate in respect of quantity but not in respect of the duration of shedding salmonella. Serological quantitation of specific Ig-classes (DIG-ELISA) did not allow to identify a specific Ig-class responsible for protection.