Metabolic disorder of amino acids, fatty acids and purines reflects the decreases in oocyte quality and potential in sows.

Oocyte quality is closely related to female fertility. Nevertheless, core nutritional metabolites influencing oocyte quality are unclear. Herein, comprehensive metabolomics analysis of follicular fluid, serum, and urine from low reproductive performance (LRP) and normal reproductive performance (NRP) sows was conducted. Twenty-seven, fourteen and sixteen metabolites (involved in metabolism of amino acids, fatty acids, purine and pyrimidine) were altered in follicular fluid, serum and urine, respectively, in LRP compared with NRP sows, and could decrease oocyte quality and developmental potential, ultimately leading to low fertility. Deoxyinosine, guanidine acetate, thymidine, 5,6-epoxy-eicosatrienoic acid, carnosine, docosahexaenoic acid and carbamoyl phosphate in follicular fluid, cysteine, carnitine, serotonin, hypoxanthine, valine and arginine in serum, as well as carnitine, phenyl glycine, N-acetyl glutamine, propionyl carnitine and choline in urine could be selected as diagnostic markers to indicate oocyte quality. Consistent with metabolomics data, we confirmed changes in concentrations of fatty acids and amino acids in follicular fluid. Targeting purine metabolism, elevating levels of deoxyinosine in in-vitro maturation medium of porcine oocyte significantly promoted the blastocyst rate. Collectively, this study provided new information of potential targets for predicting oocyte quality and developmental potential, and may help with strategies for early diagnosis or therapeutic/dietary intervention in improving reproductive outcomes.