[Use of a standard radioimmunological analysis system for determining prolactin in the blood plasma of swine, sheep and bulls].

The system has been developed for radioimmunologic determination of the blood prolactin content in domestic animals--pig, sheep and bull, using common antiserum for the pig prolactin. This antiserum has a high antibody titer and can bind with large affinity not only the pig but also sheep and bull prolactins. Incubation system contains a final volume of 300 microliter of antiserum (1:192 000), 125I5-labelled pig hormone (30 000 imp/min) and standard or dofining hormone (0.5 to 100 micrograms/ml). To separate the free- and antibody-bound hormone fractions the double antibody method was used.