A SOLID PHASE RADIOIMMUNOASSAY FOR OVINE AND CAPRINE PROLACTIN USING SEPHAROSE 6B: ITS APPLICATION TO THE MEASUREMENT OF CIRCULATING LEVELS OF PROLACTIN BEFORE AND DURING PARTURITION IN THE GOAT

Abstract

SUMMARY A rapid solid phase radioimmunoassay for ovine and caprine prolactin is described utilizing antibodies chemically bound to Sepharose 6B. Prolactin was measured in blood samples taken from goats at varying intervals before the onset of the first stage of labour. The concentration of prolactin rose 5–35 h before parturition to a level 2·6–4·5 times the lowest concentration found earlier in gestation. The results of serial samples taken during the first and second stages of labour indicate that the intense uterine contractions associated with the expulsion of the kid are associated with a large increase in the level of prolactin in the blood.