Metallotyping of ketotic dairy cows reveals major alterations preceding, associating, and following the disease occurrence

Introduction: Ketosis is a common metabolic disorder, which is characterized by elevated concentrations of ketone bodies or ketoacids in three body fluids including blood, urine, and milk. Two of the ketones including β-hydroxybutyric acid and acetoacetic acid are strong acids which at high concentrations trigger ketoacidosis influencing physiological functions of various tissues and organs. Objectives: The objectives of this study were to: (1) investigate mineral alterations in both serum and urine of preketotic, ketotic, and postketotic cows, (2) identify potential predictive and diagnostic mineral biomarkers for ketosis in serum and urine, and (3) better understand the role of minerals in the pathobiology of the disease. Methods: Inductively coupled plasma mass spectrometry metallotyping was performed in the serum and urine of six cases of ketosis and 20 healthy controls cows at −8 and −4 weeks prepartum, at disease diagnosis week, and at +4 and +8 weeks postpartum. Results: Data showed that concentrations of aluminum (Al), iron (Fe), manganese (Mn), and arsenic (As) were greater (P < 0.001) in the serum of preketotic, ketotic and postketotic cows at most of the tested time points. Moreover, boron (B) and Al as well as calcium (Ca), phosphorus (P), potassium (K), and magnesium (Mg) were found to be elevated in the urine of preketotic and postketotic cows (P < 0.001). Conclusions: It is concluded that alterations of mineral elements observed in the serum and urine of preketotic, ketotic, and postketotic cows might be related to the state of chronic acidosis in those cows. The mineral elements identified in both serum and urine can be used as biomarkers to early diagnose ketosis at its pre-subclinical state and develop preventive interventions in the future.