Table 1.
Mean (± SEM) density of equine preantral follicles in ovarian biopsy fragments collected during anestrous and diestrous phases.
Table 2.
Mean (± SEM) density of equine preantral follicles in ovarian biopsy fragments collected from left and right ovaries in anestrous and diestrous phases.
Table 3.
Mean (± SEM) number of equine preantral follicles in ovarian biopsy fragments collected during anestrous and diestrous phases.
Table 4.
Mean (± SEM) number of equine preantral follicles in ovarian biopsy fragments collected from left and right ovaries in anestrous and diestrous phases.
Fig 1.
Mean (± SEM) percentage of equine preantral follicles according to class distribution in ovarian biopsy fragments collected during anestrous and diestrous phases.
a,b Within the same follicle class, values without a common letter differed (P < 0.05). ‡ Tended to differ from transitional follicles during the same phase (P < 0.09).
Fig 2.
Mean (± SEM) percentage of morphologically normal equine preantral follicles according to class distribution in ovarian biopsy fragments collected during anestrous and diestrous phases.
a,b Within the same follicle class and overall mean, values without a common letter differed (P < 0.05). Because of the low number of primary follicles (n = 5) observed in the anestrous phase, transitional and primary follicles classes were combined.
Table 5.
Percentage of morphologically normal equine preantral follicles in biopsy fragments collected during anestrous and diestrous phases, and presence of different ovarian structures (antral follicles and corpus luteum).
Fig 3.
Mean (± SEM) density of equine ovarian stromal cells in biopsy fragments collected from left and right ovaries during anestrous and diestrous phases.
a,b Within the same ovarian side and overall mean, values without a common letter differed (P < 0.05). A,B Within the same reproductive phase, left and right ovary values without a common letter differed (P < 0.05).
Fig 4.
Correlation between (A) follicular density and stromal cell density, and (B) number of preantral follicles and stromal cell density.
The association among variables (black line) was evaluated by Spearman correlation coefficient [(A): r = 0.15, P < 0.07; (B): r = 0.16, P < 0.05]. Each point on the chart represents one ovarian fragment evaluated (n = 142).
Fig 5.
Mean (± SEM) (A) follicle density, (B) number of preantral follicles, and (C) ovarian stromal cell density in biopsy fragments collected from ovaries with antral follicles and corpus luteum.
Dashed line represents the average for (A) follicle density, (B) number of preantral follicles, and (C) stromal cell density. a,b Within the same parameter evaluated, values without a common letter differed (P < 0.05). Follicles ≤26 mm: 6 to 26 mm in diameter; Preovulatory follicle: ≥36 mm; and Corpus luteum: ≥30 mm, days 4 to 12 of estrous cycle.
Fig 6.
Mean (± SEM) area (mm2) of equine ovarian structures (antral follicles and corpus luteum) during the biopsy pick-up procedures performed during anestrous and diestrous phases.
a,b Within the same ovarian side and overall mean, values without a common letter differed (P < 0.05). A,B Within the same reproductive phase, left and right ovary values without a common letter differed (P < 0.05).
Fig 7.
Correlation coefficients between (A) follicle density, (B) number of preantral follicles, and (C) ovarian stromal cell density with area of ovarian structures (antral follicles and corpus luteum).
The association among variables (black line) was evaluated by Spearman correlation [(A): r = 0.21, (B): r = 0.21, (C): r = 0.10; P < 0.05]. Each point on the chart represents one ovarian fragment evaluated.
Fig 8.
Model proposing the difference of follicle density, number of preantral follicles, and stromal cell density among anestrous (A) and diestrous (B) phases.
The increase of the area of ovarian structures during the diestrous phase due to the presence of large follicle(s) and corpus luteum may increase the ovarian compression and consequently the clustering of preantral follicles and stromal cells per unit area in ovarian fragments harvested by biopsy procedure.