Successful lactation induction in non-pregnant gilts.

A protocol to induce lactation was applied to non-pregnant gilts. In Experiment I, five gilts with estrus synchronized through oral supplementation of 20 mg Altrenogest for 18 d received: 10 mg estradiol cypionate (EC) on the last day of estrus expression (D0); 10 mg EC and 300 mg long-acting progesterone (P4) on D26; and two 0.53 mg doses of a prostaglandin F2α analogue (PGF) 12 h apart on D36. Blood was collected on D12, D19, D26 and D33. Milk secretion started in all gilts 24 h after PGF administration and lasted at least 8 d. Milk samples were collected from D37 to D45. The serum P4 concentration was lower on D12 than subsequently (P < 0.05), but the estradiol concentration was unaltered (P > 0.05). The milk produced during the induced lactation was generally richer in protein and poorer in fat compared to the milk from the lactation of a reference sow. In Experiment II, the same protocol induced lactation in two gilts, which nursed fostered piglets for 22 d. Thus, lactation was induced in all treated gilts and the milk produced was capable to nurture fostered piglets.