Gestation In Gilts Research Articles

Effect of purified zearalenone on early gestation in gilts.

Purified zearalenone (Z) was added to the diet of gilts from d 2 to 15 postmating. Gilts received either 0, 5, 15, 30, 60 or 90 ppm Z (three to five gilts per dose) in 1.8 kg of feed daily. Serum concentrations of progesterone and estradiol-17 beta were determined weekly. On d 13 to 15 and 40 to 43 postmating, blood samples were drawn from a cannula at 20 min intervals for 4 h and analyzed for luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin (PRL). Gilts were killed 40 to 43 d postmating and embryonic development was assessed. Treatment with 5, 15 or 30 ppm Z had no effect on embryonic development when compared with 0 ppm. No fetuses were present in gilts fed 60 to 90 ppm Z, but two gilts given 60 ppm Z had remnants of fetal membranes in the uterus. The histologic appearance of reproductive tract tissues from the gilts given 60 ppm Z was similar to that from pregnant gilts. Tissues from gilts given 90 ppm Z appeared to be stimulated by both estrogen and progesterone. Serum concentrations of progesterone were decreased at 2, 3 and 6 wk postbreeding in gilts fed 60 and 90 ppm Z. Serum concentrations of estradiol-estradiol-17 beta were decreased at 4 wk postbreeding in gilts fed 60 and 90 ppm Z.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of one-day or conventional flushing on ovulation rate and litter size at 28 days gestation in gilts.

A total of 146 gilts were randomly assigned at estrus to one of the following flushing treatments: (1) control—2.27 kg of feed daily; (2) 1-day flush—2.27 kg of feed daily, except for a 24-hr. period of ad libitum feed intake during mating estrus; and (3) 14-day flush—2.27 kg of feed daily except for a 2-week period of ad libitum feed intake starting on day 7 of the estrous cycle. Average ovulation rate in the 14-day flush group (15.7 ova) was significantly (P<.01) greater than that of gilts flushed for 1 day (14,2 ova) or in controls (13.8 ova). Gilts flushed for 1 day ovulated an average of 0.4 ova more per gilt than controls, but this difference was not significant (P<.05). Season did not significantly affect ovulation rate (spring, 14.5 vs. summer, 14.6). The left ovary ovulated more ova (P<.10) than the right (7.5 vs. 7.0). Gilts flushed for 14 days had significantly (P<.01) more live embryos per litter (13.0) than the 1-day flush group (11.3) or control gilts (10.9).

Uterine capacity at two stages of gestation in gilts following embryo superinduction.

Uterine capacity at two stages of gestation in gilts following embryo superinduction.