Associations of β-hydroxybutyrate, cholesterol, triglycerides and high-density lipoproteins to non-esterified fatty acids pre- and postpartum

Abstract

While laboratory tests for measuring the concentration of NEFA in serum are well established, a point of care test to determine NEFA on farm is not available. Several hand-held measuring devices, however, have been validated for measuring β-hydroxybutyrate (BHBA) in cattle or cholesterol, triglycerides (TAG), and high-density lipoproteins (HDL) in human medicine, respectively. The objective of this study was to evaluate the association between NEFA and different parameters related to lipid metabolism. Specifically, we set out to determine if it is feasible to predict the concentration of NEFA by means of surrogate measures. The concentration of BHBA was determined by a hand-held device evaluated for use in cows, whereas the concentrations of the other parameters were determined by laboratory analysis because hand-held devices for cholesterol, TAG and HDL are only evaluated for human medicine so far. A total of 254 cows were included in the trial. One blood sample was taken from each cow between d 10 and d 1 prepartum. Second and third samples were collected on d 2 and d 10 postpartum, respectively. The coefficients of correlation between parameters were calculated and a receiver-operator characteristic curve analysis has been used. The prediction of NEFA concentrations using only one of the parameters was insufficient. However, a NEFA concentration ≥0·5 mEq/l could be predicted with a high sensitivity (i.e. Se = 0·88) and specificity (i.e. Sp = 0·93) from d 3 to d 1 prepartum and a NEFA concentration ≥0·7 mEq/l could be reliably predicted on d 2 postpartum (i.e. AUC = 0·89, Se = 0·89, Sp = 0·76) when using a combination of BHBA, cholesterol and TAG as surrogates. Overall, our results suggest that a combination of different parameters of lipid metabolism could be used as surrogates for NEFA.

Determinación de ácidos grasos no esterificados, β-hidroxibutirato, triacilglicerol y colesterol durante el balance energético negativo en vacas Holstein

“…El metabolismo de las vacas lecheras, responde a esta situación con la hidrólisis de TAG almacenados en el tejido adiposo, obteniendo AGNE que pueden ser oxidados dentro de la matriz mitocondrial hepática (García et al, 2015), para la producción de acetil-Coenzima A (Wakil y Abu-Elheiga, 2009). Durante la condensación consecutiva de acetil-Coenzima A, se obtiene acetoacetato (AcAc), como producto alterno (Ruoff et al, 2016), y una parte de él se reduce por la β-hidroxibutirato deshidrogenasa a β-HBA (García et al, 2015). Por lo tanto, durante los primeros días de lactancia su concentración se eleva ligeramente en respuesta a la movilización lipídica, y desciende cuando el balance energético se vuelve positivo (Sun et al, 2016).…”

“…(van Hoeij et al, 2017). El BEN, conduce a una disminución de glucosa (GLU) e insulina en sangre (Ruoff et al, 2016), y movilización de ácidos grasos no esterificados (AGNE), estos ácidos grasos se utilizan como fuente de energía por la β-oxidación (Abdelli et al, 2017), pero cuando la movilización de ellos es excesiva, se reestructuran como triacilglicerol (TAG). Unido a este proceso, se activan vías hepáticas alternativas, destacando la formación de cuerpos cetónicos como β-hidroxibutirato (β-HBA) y la formación y almacenamiento hepático de colesterol (COL) (Sun et al, 2016).…”

Obesity-Related Metabolic Dysfunction in Dairy Cows and Horses: Comparison to Human Metabolic Syndrome

“…Lipolysis can be detected measuring the serum NEFA and β-hydroxybutyrate concentration under laboratory conditions [52], but no test is available for the on-field assessment of NEFA level. Thus, in such conditions, elevated NEFA levels might be identified via correlation with other parameters related to lipid metabolism (increased cholesterol, increased TG, decreased HDL), for which handheld devices are available [53].…”