Haematometra: A rare complication of cystic ovary in a sub-adult royal Bengal tigress (Panthera tigris tigris)

Introduction

Ovarian cysts are fluid-filled formations that arise within or on the surface of the ovaries in female felines. They are categorized into follicular cysts, lutein cysts, cysts of underlying epithelial structure, cystic rete ovarii, and cystic corpus luteum (Johnston et al., 2001) [4] . Each kind exhibits unique histological features and clinical consequences. Cystic formations represent a notable clinical issue in small animal reproductive, frequently resulting in infertility if left untreated (Knauf et al., 2018) [5] . Ovarian cysts, typically originating from mature or atretic follicles, do not undergo ovulation and persist in the ovary, hence obstructing the re-initiation of folliculogenesis and ultimately causing subfertility in the queen (Gharagozlou et al., 2014) [3] . Follicular cysts are thin-walled ovarian formations that can be singular or numerous and may occur unilaterally or bilaterally. The predominant variety of ovarian cyst is the functional follicular cyst, which produces estrogen (Johnston et al., 2001) [4] . Follicular cysts may induce behavioral disorders such as extended estrus, bone marrow suppression, and uterine hyperplasia due to sustained elevation of estradiol. Follicular cysts may be detected using behavioral indicators, ultrasonography, and serum estradiol assessment (Gelberg et al., 1984; Johnston et al., 2001) [2,4] . In instances of follicular cysts, medical treatment focuses on stimulating ovulation or luteinization with the administration of either gonadotropin-releasing hormone (GnRH) or human chorionic gonadotropin (hCG) (Ortega-Pacheco et al., 2012) [6] . The administration of gonadotrophins, stimulates estrous behavior and ovarian activity (Youssefi et al., 2015) [8] . This article details the diagnosis and treatment of a sub-adult tigress with follicular ovarian cysts and resultant haemometra that was successfully managed.

Case History and Observation

A 3-year-old Sub-adult tigress from Chandrapur was caught in Man-animal conflict and was brought to Gorewada Rescue Centre for further management. The animal was kept under Quarantine Period and during this period the tigress exhibited vaginal bleeding that progressively intensified over a span of 10 days. The animal was monitoring to find out the cause of bleeding and no wounds were discovered over the body.

The animal was then taken into treatment cage. Physical examination indicated normal rectal temperature (101.5°F), with normal appetite, urine, and faeces. The animal exhibiting haematometra (uterine bleeding) was noticed during the nocturnal hours, as illustrated in Fig. 1. The animal was subjected to CBC and serum biochemistry that revealed Hb-11.8 g/dl, RBC-6.58 x 10 6 /cu.mm, TLC-20.69 x 10 3 /cu.mm, DLC (N-77%, L-17%, M-2%, E-4%, B-0%). Thus all the parameters were within normal range as delineated in Table 1. Ultrasonography was carried out using a linear probe of 10-5 MHz and showed the presence of bilateral hypo-echoic to anechoic follicular cyst/ovarian cyst of 0.81 cm and 0.76 cm, along with the presence of blood in the uterus, as illustrated in Figures 2 and3, respectively. The imaging also revealed thicker uterine endometrium, suggestive of endometrial hyperplasia. Vaginal impression smear revealed presence of anucleated cornified epithelial cells indicating that the animal was in estrus as shown in Fig 4.

Treatment and Discussion

The Tigress was treated with 2000 IU of HCG intramuscularly and Tranexamic acid at 10 mg/kg orally, accompanied by supportive therapy with iron and multivitamins. The animal exhibited improvement with symptoms regression by the fifth day. Ovarian cysts, usually arising from mature or atretic follicles, fail to ovulate and remain in the ovary, hence hindering the resumption of folliculogenesis and later leading to sub-fertility in the Felines (Gharagozlou et al., 2014) [3] . Elevated serum estrogen levels result in persistent activation of estrogen receptors, ultimately causing fluid retention in the uterus and expansion of the uterine horns. A follicular cyst in both ovaries may have contributed to fluid build-up by stimulating estrogen receptors Cystic endometrial hyperplasia (CEH) arises from an aberrant uterine response to recurrent progestational stimulation during the luteal phase of the estrous cycle potentially exacerbated by estrogen (Rangasamy et al., 2017) [7] .

In cases of follicular cysts, medical intervention aims to induce ovulation or luteinization with the administration of gonadotropin-releasing hormone (GnRH) or human chorionic gonadotropin (hCG) (Ortega-Pacheco et al., 2012) [6] . Therapeutic management presents clinical dilemmas about conservative versus surgical interventions. Despite hormonal therapy employing gonadotropin-releasing hormone analogs (GnRH) or human chorionic gonadotropin (hCG) demonstrating success rates of around 63% in specific studies, the potential for recurrence and the prevalent presence of uterine pathology often necessitate surgical intervention (Domrazek et al., 2025) [1] . The current investigation indicated that the animal well responded to HCG treatment, as also reported by Ortega-Pacheco et al.

(2012) [6] , and the animal was observed for one year without any recurrence of symptoms.

Acknowledgement

AcknowledgementsThe authors are thankful to Hon'ble PCCF (WL) and Chief Wildlife Warden, Maharashtra State, the FDCM Pvt. Ltd and Divisional Manager, Gorewada Project, Nagpur for granting permission to manage cystic ovary in a Sub-adult Tigress at Wildlife Research and Training Centre, Nagpur and also for providing the facilities required for its successful management.

References

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