Characterization of effects of zearalenone in swine during early pregnancy.

Mature gilts (n = 16) were hand mated and randomly assigned to 1 of 4 groups of 4 gilts each. Treated gilts had 108 mg of purified zearalenone added to their diet on postmating days (PMD) 2 to 6, 7 to 10, or 11 to 15. Control gilts were given the same diet without added zearalenone. On PMD 6, 10, and 15, control gilts had venous cannulas placed in the jugular vein, and blood samples were taken at 20-minute intervals for 4 hours before feeding and 4 hours after feeding. Samples were collected from treated gilts on the last day that zearalenone was consumed. Samples were analyzed for follicle stimulating hormone, luteinizing hormone (LH), and prolactin. Single blood samples were taken by venipuncture on PMD 8, 12, 16, 20, 24, and 28 and at euthanasia and were analyzed for serum concentration of progesterone and estradiol-17 beta. All gilts were euthanatized 30 to 32 days after mating, and fetal development was assessed. Three gilts that were given zearalenone on PMD 7 to 10 were not pregnant and had regressing corpora lutea on the ovaries at euthanasia. All other treated and control gilts were pregnant. Serum samples from treated gilts on PMD 10 and 15 had lower mean prolactin concentrations than did those from controls. The number of LH spikes were fewer (P less than 0.05) in gilts that were given zearalenone on PMD 15 compared with those in controls on PMD 15. Serum progesterone concentrations indicated that corpora lutea regressed between PMD 20 and 28 in nonpregnant gilts.(ABSTRACT TRUNCATED AT 250 WORDS)