Ultrasonographic evaluation of ovarian morphology and blood flow in prepubertal and pubertal cats

Abstract

The aim of this study was to evaluate two‐dimensional and Doppler ultrasonographic changes of feline ovaries before and during puberty. Nine, 3‐month‐old female cats were followed until puberty (Day 1). Two‐dimensional and Doppler ultrasound evaluations of the ovaries were carried out on Days ‐50, ‐20, ‐7 and 1. Longitudinal and transverse sections of the ovaries were measured and all anechoic spherical structures were considered to be follicles. The number of follicles >1 mm and the maximum diameter of the largest follicle were recorded. Peak systolic velocity and end diastolic velocity of intraovarian arteries were also measured to automatically calculate the resistive index (RI). The mean ovarian longitudinal diameter increased gradually throughout the study from 8.6 to 10.7 mm (p < 0.05). While four cats presented multiple anechoic spherical structures <1 mm diameter throughout the study, the remaining five animals had these structures only on Days ‐50 and ‐20. On Days ‐20, ‐7 and 1, the mean number of follicles were 1.4 ± 0.7, 2.5 ± 0.8 and 4.8 ± 1 respectively (p < 0.01). The largest follicles at the same time points were 1.1 ± 0.2 mm, 1.9 ± 0.3 mm and 2.6 ± 0.5 mm respectively (p < 0.05). The RI of the intraovarian arteries declined throughout the study period (p < 0.01). It is concluded that, in female cats, ovarian dimensions, follicle number and intraovarian blood flow increased from 3 months of age to puberty.

Ovarian and uterine two-dimensional and Doppler ultrasonographic changes in the feline peri-estrus period

“…Similar results were found in pubertal estrus in queens. 27 This phenomenon is also similar to that observed in bitches, where intraovarian perfusion increases gradually from proestrus to the preovulatory period. 40 According to previous reports on the three-dimensional architecture of ovarian vessels in murine models, follicular development is accompanied by an increase in vasculature branching.…”

“…The sizes of the ovaries and uterine body observed in this study were similar to those reported in previous ultrasonographic studies in pubertal and adult queens. 11,27 Despite the architecture differences found in these cycles (ie, follicular growing, thickening of uterine layers), no dimension changes were found in the organs using this equipment and settings. Interestingly, the maximal ovarian diameter was registered on day 5, probably due to the largest follicles being detected on that day.…”

“…For ovarian Doppler assessment, the intraovarian arteries of the right and left ovaries were detected within the ovarian tissue using color Doppler and pulsed-wave Doppler was performed to obtain the waveforms. 27 For uterine Doppler assessment, two-dimensional ultrasonography was used to identify the uterine body in a transversal axis. The main right and left uterine arteries adjacent to the uterine body were localized using color Doppler and pulsed-wave Doppler was performed to obtain the waveforms.…”

“…7,[23][24][25][26] Doppler ultrasonographic characterization of domestic cat ovaries has been carried out in pubertal cats, but information on postpubertal queens is lacking. 27 It is hypothesized that during estrus and shortly after it, feline ovaries and uterus develop structural modifications associated with vascular changes. Thus, the aim of this study was to evaluate twodimensional and Doppler ultrasonographic changes of the ovary and uterus during estrus and the early postestrus period in feline species.…”

Advanced ultrasound techniques in small animal reproduction imaging

“…The breed, the phase of oestrus cycle and also the pregnancy history affected Doppler parameters of the uterine artery, while RI did not differ during the different phases of the cycle for the same breed (Freitas, Mota, Silva, & Silva, ). In cats, ovarian blood flow seemed to increase during sexual development until puberty (Vercellini et al, ).…”