Selected Metabolic and Hormonal Profiles during Maintenance of Spontaneous Ovarian Cysts in Dairy Cows

Information is lacking regarding the relationship between metabolic and hormonal profiles and the maintenance of spontaneous ovarian cyst disease in dairy cows. For this reason, the concentrations of non-esterified fatty acids (NEFA), insulin-like growth factor I (IGF-I) and cortisol (C) were investigated during the spontaneous course of ovarian cyst disease in dairy cows (n = 6) between the 7th and 16th weeks post-partum (PP). The control group consisted of normally cycling cows (n = 6). Blood samples were collected twice a day, and plasma was analysed using different techniques. Progesterone and 15-ketodihydro-PGF₂α plasma profiles were investigated to confirm the ovulatory or anovulatory conditions of the cows. Cortisol plasma levels were not significantly different among sampling times within each group or between the two groups. NEFA plasma levels were significantly higher in cycling cows compared to cystic cows at the 16th week PP (p < 0.01), but with rather low values, indicating by now sparse mobilization of fat stores. Insulin-like growth factor I plasma concentrations were higher in cystic cows during the 8th, 10th, 11th (p < 0.01) and 16th week PP (p < 0.05), indicating that the presence of ovarian cysts coincides with increased IGF-I levels. These results suggest no influence of cortisol and NEFA levels in cysts maintenance, while a possible involvement of IGF-I can be suspected not only in the pathogenesis, as already known, but also in the maintenance of spontaneous cystic ovarian disease in cattle.