Farm animal models for the study of the reproductive features of polyendocrine metabolic ovarian syndrome.

Polyendocrine metabolic ovarian syndrome (PMOS) is a multifactorial disease representing one of the most prevalent causes of infertility in women, affecting up to 15% of females of reproductive age. PMOS is characterized by a combination of ovarian dysfunction, hyperandrogenemia and endocrine derangement, frequently accompanied by metabolic comorbidities including insulin resistance and obesity. Despite its clinical importance, the mechanisms underlying its pathogenesis remain incompletely understood. Rodent models have been foundational for genetic and mechanistic studies but differ from humans in fundamental aspects of reproductive physiology and neuroendocrine rhythms may not recapitulate the PMOS phenotype at either the ovarian or the neuroendocrine level. This review evaluates current farm animal models of PMOS in humans with a special emphasis on ovarian and endocrine function. Farm animal species, particularly sheep, cattle, horses and pigs, offer complementary advantages compared to rodents: comparable estrous cycle length, well-characterized follicular wave dynamics, and the capacity for longitudinal endocrine and ultrasonographic monitoring at a scale not feasible in human studies. While no current animal model parallels PMOS in its entirety, domestic animals may be useful to disentangle the mechanisms that are participating in PMOS at the ovarian and endocrine level, such as follicular arrest and hormonal dysregulation. The adoption of farm animals in the study of PMOS will complement mechanistic and clinical studies for future diagnosis and therapy.