@article{huff_esbenshade_1992, title={INDUCTION OF FOLLICULAR DEVELOPMENT AND ESTRUS IN PREPUBERTAL GILTS WITH GONADOTROPINS}, volume={27}, ISSN={["0378-4320"]}, DOI={10.1016/0378-4320(92)90057-K}, abstractNote={Two experiments were conducted to examine the effect of luteinizing hormone (LH) and follicle stimulating hormone (FSH) on follicular development in gilts. The gonadotropins were given via hourly i.v. infusions. In Experiment 1, gilts were given saline (n = 9), a pituitary extract (n = 6), or 7.5 (n = 4), 15 (n = 4), 30 (n = 4) or 60 (n = 5) ng LH kg−1 body weight (BW) hourly for 144 h, after which ovaries were examined by laparoscopy. The proportion of gilts given pituitary extract, or 30 or 60 ng LH kg−1 BW that had corpora lutea or follicles greater than 7 mm in diameter at the time of laparoscopic examination was significantly greater than the proportion of gilts treated with saline or lower amounts of LH. Hourly infusions of a pituitary extract and LH increased (P < 0.05) serum LH concentrations with each infusion, but did not change FSH concentrations around each infusion, or alter basal LH, FSH or estradiol concentrations. In Experiment 2, gilts were given saline (n = 4) or 15 ng LH kg−1BW and FSH at a rate of 1 (n = 5), 2 (n = 5) or 4 (n = 5) ng kg−1 BW. Four of five gilts given 15 ng LH and 4 ng FSH kg−1 BW exhibited estrus, whereas none of the other gilts showed estrus (P < 0.02). Administration of LH and FSH increased LH concentration within 10 min after each treatment, but did not influence concentrations of FSH after each treatment, or basal concentrations of LH, FSH or estradiol. The pattern of endocrine events observed in gilts exhibiting estrus was similar regardless of treatment or experiment and was similar to that observed previously in gilts undergoing follicular development. These results indicate that LH can stimulate follicular development, estrus and ovulation in prepubertal gilts if given hourly in sufficient quantities and that FSH acts synergistically with LH in causing follicular development when given in a pulsatile manner.}, number={2-3}, journal={ANIMAL REPRODUCTION SCIENCE}, author={HUFF, BG and ESBENSHADE, KL}, year={1992}, month={Apr}, pages={183–194} }