Prostaglandin F2 alpha in blood plasma and milk of non-pregnant and pregnant buffaloes (Bubalus bubalis).

Radioimmunoassay of prostaglandin F2 alpha (PGF2 alpha) was standardised for sufficient precision, accuracy, sensitivity and specificity. The changes of PGF2 alpha were monitored in peripheral blood plasma and milk of 28 Murrah buffaloes. There were considerable individual variations of PGF2 alpha concentration in blood plasma (27.6 to 110.8 pg/ml) and milk (80.3 to 180.4 pg/ml). A non-significant increase of PGF2 alpha concentration (P greater than 0.05) was observed at the end of the cycle of non-pregnant animals in both fluids but no such increase was observed in pregnant animals. The concentration of PGF2 alpha in milk was significantly higher (P less than 0.01) than that of blood plasma and was positively correlated in non-pregnant (r = 0.738) and pregnant animals (r = 0.385).