Effects of follicular and luteal cysts on reproductive organs, interstitial glands, and mast cell distribution in buffalo ovaries.

A significant factor contributing to reproductive failure in dairy cattle that raised the possibility of culling was ovarian cysts. Its etiology and pathogenesis remained a puzzle, but investigation of the associated tissue modulation, particularly those of the ovaries, oviduct, and uterus, might shed some light on its development. Therefore, the current study aimed to assess changes induced by follicular and luteal cyst formation in the ovary, oviduct, and uterus. In addition, the aims also involved the effect of these cyst formations on the interstitial glands and mast cell distribution in the ovaries of dairy cows. Genital organs of healthy, non-pregnant buffalo-cows (n = 45) were collected from the abattoir. According to the ovarian status, buffalo-cows were divided into three equal groups (15 for each): one normal healthy group was the control group (Ctrl group) and two diseased groups. The first diseased group was the group of buffalo-cows with follicular cysts (FC group), while the second one was the group with luteal cysts (LC group). Blood and tissue samples were collected to determine progesterone levels and do histological investigations of the reproductive organs. Hematoxylin and eosin, Alcian blue-PAS, and Alcian blue-safranin-O stains were used for investigating ovarian tissues, interstitial glands (IGs), and mast cells (MCs), respectively. Results showed that significantly reduced thickness of the ovarian cortex and medulla, loss of ovarian folliculi, hemorrhage, and dilated blood vessels were observed in the FC and LC groups compared to the Ctrl group. In addition, the cystic ovaries significantly reduced interstitial gland count that was characterized by histopathological alterations that included atrophied and apoptotic cells and fragmentation, fading, and pyknotic nuclei. Likewise, in cystic ovaries, mast cell counts were found significantly reduced compared to the Ctrl group. The ovarian cysts significantly reduced the length and diameter of oviductal mucosal villi that were characterized by severe histopathological fluctuation in the ciliated cells and protruding and non-protruding secretory cells. For the uterus, the average thickness of the myometrium and endometrium in the ovarian cyst groups was significantly reduced compared to the Ctrl group. Furthermore, histopathological changes in the uterine glands, including severe apoptotic alterations, fading, pyknotic, and fragmented nuclei, were observed. In conclusion, the current study indicated that follicular and luteal cyst formations in the ovary induced various changes in the reproductive organs, interstitial glands, and mast cell distribution in the ovarian stroma, providing insights into the potential pathogenesis of cyst formation.