Peripubertal ovarian and uterine ultrasonographic changes in bitches

VERCELLINI R; GOBELLO C; MENDOZA P; OLGUÍN S; CZERNIGOW M; ARIAS DO; BLANCO PG

Congreso; 23rd EVSSAR Congress; 2021

European Veterinary Society of Small Animal Reproduction

Introduction and objectiveIn female dogs, ultrasonographic characterization of the ovaries and uterus during sexual maturation has not been carried out so far. Thus, the aim of this study was to describe two-dimensional and Doppler ultrasonographic peripubertal changes of canine ovary and uterus. Materials and methods Eight, 3-month-old, mixed-bred, weighing 3.3±0.42 (1.2-4.9) kg female dogs were included in this study. Pubertal estrus (Day 1) was diagnosed by the first appearance of more than 90% superficial vaginal epithelial cells and estrous behavior. Two-dimensional and Doppler ultrasound evaluations of the ovaries and uterus were carried out on Days -140, -90, -60, -30, 1 and 20, with a 14 MHz linear-array transducer (Toshiba Nemio XG, Japan). Experimental days were retrospectively determined. Longitudinal and transverse sections of the ovaries and uterine body diameter were measured. All anechoic spherical structures in the ovarian parenchyma were considered to be antral follicles, whilst hypoechoic or thick-walled cavitated structures (>1mm) were recorded as corpora lutea (CLs). The mean number and size of follicles >1mm and CLs, and the maximum diameter of the largest follicle and corpus luteum were recorded. Peak systolic velocity and end diastolic velocity of intraovarian and uterine arteries were also measured to automatically calculate the resistance index (RI). Repeated measures ANOVA followed by Tukey test was carried out to evaluate the effect of time on the two-dimensional and Doppler ultrasonographic parameters. Results All the bitches achieved puberty at 10.5±0.5 (8-13) months of age, weighing 9.3±1.8 (3.9-17.9) kg, which represented 95 ± 1.6% of their adult body weight. The mean ovarian longitudinal (p