The effects of anti-galactagogue (sage, parsley extract) and anti-inflammatory (echinacea extract) feed supplements on prolactin levels and fertility in the re-pregnancy of lactating Merino ewes

The purpose of this study was to examine the effects of anti-galactagogue (sage, parsley extract) and anti-inflammatory (echinacea extract) feed supplements on prolactin levels and fertility in the re-pregnancy of lactating Merino ewes. Eighty ewes were randomly assigned to one of two groups: control and treatment. In treatment group (Stop Lactin) group (n = 40) ewes were treated with Stop Lactin® 60 ml on day 0 orally by syringe. The control group (Control) (n = 40), ewes were not treated with any anti-galactagogue feed supplements. On day 0, a vaginal sponge containing 60 mg of medroxyprogesterone acetate was inserted for seven days. On day 7, all ewes received an intramuscular injection of 500 IU PMSG. The study results indicated no statistically significant differences between the Control group and Stop Lactin group in terms of conception rates (87.2% and 78.1%), late embryonic-early fetal mortality rate (20.6% and 8.0%), lambing rate (79.4% and 92%), twin rate (29.6% and 13.0%) and litter size (1.30 and 1.13). Estrus rates (97.5% and 82.1%, p = 0.050) tended to be higher and pregnancy rates (85.0% and 64.1%, p = 0.037) was found to be significant in the control group compared to the Stop Lactin group. The effect of treatment (P = 0.209) on serum prolactin levels and the interaction between treatment × day (P = 0.874) were both found to be insignificant. It is concluded that anti-galactagogue and anti-inflammatory feed supplements did not reduce prolactin concentration and did not improve fertility in lactating Merino ewes.