The importance of the diestrus stages (early, middle, late) to the diagnosis of the endometrial disease in the bitch

Abstract

The endometrium is the uterine layer wherein embryo implantation and development take place.Complete knowledge of the endometrium's normal histology is critical for advancing the diagnosis of subclinical endometrial diseases. Several researchers studied subclinical endometritis (END) in different species but the cause/s remain unknown. Furthermore, simple and reliable diagnostic tools are still necessary to diagnose subclinical END. In the bitch, diestrus has been selected as the stage of the reproductive cycle to perform the diagnosis of END. This work aimed to perform morphometric and cytological studies in bitches with normal endometrium (NE) and END in diestrus' stages. Forty-ve mixed-breed clinically healthy bitches, in diestrus, were used in this study. Biopsies and cytology were obtained from uterine horns, processed, and examined using a microscope. Samples from NE and END were selected, images acquired, and software for image analysis was used to measure the endometrial thickness (ET), external glandular diameter (EGD), internal glandular diameter (IGD), glandular density, and glandular cell height (CG). Signi cant differences were observed in GC height, EGD, IGD, and serum P 4 concentrations along diestrus. In END, both EGD and IGD were smaller than NE. The current study showed histomorphometric characteristics that appear to be in uenced by P 4 concentrations. In our opinion, it is relevant to consider how far the bitch had progressed into diestrus at the moment of the diagnosis of endometrial disease. Data recorded in the present study could be helpful to clarify cases of bitches with unexplained infertility or subfertility.

Modulatory effect of vitamin B6 on sex hormone receptors, thyroid, and kisspeptin/kiss1r system in the uterus of pseudopregnant bitches

“…Furthermore, like cabergoline, shows higher scores in the myometrial layer. Although P 4 levels are significantly lower in late dioestrous compared to the beginning of the phase (Praderio et al., 2023; Vermeirsch et al., 1999, 2000), an increase in the amount of PR‐positive cells in these compartments may be important for the role of P 4 in maintaining uterine functions during the dioestrous period such as maintenance of pregnancy (Hinderer et al., 2021). In dogs, unlike many other species, the corpus luteum represents the only source of P 4 throughout pregnancy (Tsutsui, 1983) and it is plausible that an increase in the expression of uterine P 4 receptors represents a gain and may indicate that treatment with vitamin B6 is having a positive effect on the uterus' ability to respond to progesterone, including increasing cell proliferation.…”