Volume: 57 Issue: 1
Year: 2026, Page: 118-123, Doi: https://doi.org/10.51966/jvas.2026.57.1.118-123
Received: Sept. 12, 2025 Accepted: Nov. 18, 2025 Published: March 31, 2026
Pyometra is a common and potentially life-threatening uterine disorder in intact bitches, characterised by cystic endometrial hyperplasia, bacterial infection, and systemic inflammatory responses. The present study evaluated ultrasonographic, hormonal, and molecular changes in pyometra-affected bitches in comparison with clinically healthy dioestrus controls. Twelve intact bitches comprising six healthy dioestrus controls (Group I) and six confirmed CEHpyometra cases (Group II). Serum progesterone concentration were significantly lower in pyometra cases (24.12 ± 5.27 ng/mL ) compared to normal dioestrus bitches ( 2.65 ± 0.79 ng/mL). Ultrasonographic examination demonstrated a marked increase in uterine horn diameter (12.40 ± 1.70 vs. 20.65 ± 4.60 mm) and wall thickness (1.70 ± 0.42 vs. 3.31 ± 0.28 mm), while Doppler imaging revealed reduced resistive index (0.79 ± 0.02 vs. 0.57 ± 0.02) and pulsatility index (2.82 ± 0.26 vs 1.63 ± 0.17). Molecular analysis by qRT-PCR revealed a six-fold increase (p<0.05) in progesterone receptor (PR) expression in uterine tissue in group II animals. In conclusion, CEH-pyometra arises from a multifactorial interplay of uterine alterations, where low serum progesterone alongside high uterine receptor expression proposes compensatory upregulation that sustains disease progression, thereby underscoring its pathogenesis and highlighting potential avenues for future diagnostic and therapeutic strategies.
Keywords: Canine pyometra, cystic endometrial hyperplasia, progesterone receptor
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