Differences in the serum metabolome profile of dairy cows according to the BHB concentration revealed by proton nuclear magnetic resonance spectroscopy (1H-NMR)

Abstract

The mobilization of body reserves during the transition from pregnancy to lactation might predispose dairy cows to develop metabolic disorders such as subclinical ketosis or hyperketonemia. These conditions are not easily identifiable and are frequently related to other diseases that cause economic loss. The aim of this study was to evaluate the serum metabolome differences according to the β-hydroxybutyrate (BHB) concentration. Forty-nine Holstein Friesian dairy cows were enrolled between 15 and 30 days in milk. According to their serum BHB concentration, the animals were divided into three groups: Group 0 (G0; 12 healthy animals; BHB ≤ 0.50 mmol/L); Group 1 (G1; 19 healthy animals; 0.51 ≤ BHB < 1.0 mmol/L); and Group 2 (G2; 18 hyperketonemic animals; BHB ≥ 1.0 mmol/L). Animal data and biochemical parameters were examined with one-way ANOVA, and metabolite significant differences were examined by t-tests. Fifty-seven metabolites were identified in the serum samples. Thirteen metabolites showed significant effects and seemed to be related to the mobilization of body reserves, lipids, amino acid and carbohydrate metabolism, and ruminal fermentation.

Evaluation of the metabolomic profile through ¹H-NMR spectroscopy in ewes affected by hyperketonemia

“…There was an increase in methanol and ethanol concentrations in hyperketonemic ewes as well as in dairy cows 13 . Methanol is a potentially toxic compound which target is the retina in eyes and may explain the clinical sign of impaired vision during ketosis 14 .…”

“…Choline supports the transport of fatty acids, increases their oxidation and reduces the risk of hepatic lipidosis 22 . Choline can be converted in TMAO, a marker of oxidative stress because it reduces glycolysis and enhances β-oxidation of fatty acids 13 . Another metabolite related to β-oxidation is allantoin, a product of uric acid.…”

“…Succinate dehydrogenase is the only enzyme involved in TCA and in the electron transport chain (ETC) 62 . An alteration in succinate dehydrogenase might suggest an in uence on ETC in hyperketonemic ewes as well as in hyperketonemic dairy cows 13 .…”

“…It is commonly used to calculate energy balance during the last weeks of pregnancy and during the rst weeks of lactation 2 . It represents the gold standard for diagnosing ketosis 12,13 . The blood BHB cut-off for subclinical ketosis in sheep is ≥ 0.86 mmol/L 14,15 .…”

Integration of Multiplied Omics, a Step Forward in Systematic Dairy Research

“…However, this process would interfere with the multiple metabolic pathways and burden the liver. Current research performed that the high concentration of BHB is related to altered serum metabolic profile, anaerobic rumen fermentation, lipid metabolism, and oxidative stress further proved this point [ 49 , 79 ]. Even ketosis and fatty liver are metabolic diseases closely related to lactation physiology, the incidence and severity of those diseases are still heritable [ 122 , 123 ].…”