Expression of gonadotropin receptors within different sized sheep follicles. Cells were collected by centrifugation from follicular fluid aspirated from small (≤ 2.0 mm), medium (2.1-4.0 mm) and preovulatory (≥ 6.1 mm; *only found in the 24 hour group) follicles. Results from real time PCR are expressed as least squares means of expression relative to β-actin (2-∆Ct ×1000; arbitrary units) ± SEM. Bars within graphs with differing superscripts are different (p < .05). Expression of FSHR-1 (white bars), FSHR-2 (light gray bars), FSHR-3 (dark gray bars), and LHR (black bars) are compared within a follicle size class. Panel A) Relative expression of FSHR-3 was higher than FSHR-2 and LHR, and tended to be higher than FSHR-1 (*p = .09) in small follicles. Panel B) Relative expression of FSHR-3 was higher than other variants and LHR in medium follicles. Relative abundance of mRNA for FSHR-1 and FSHR-2 did not differ, but both were more highly expressed than LHR. Panel C) Relative expression of LHR was the highest in preovulatory follicles, while FSHR-1, FSHR-2, and FSHR-3 did not differ.