Effects of dietary l-carnitine supplementation on the response to an inflammatory challenge in mid-lactating dairy cows: Hepatic mRNA abundance of genes involved in fatty acid metabolism

This study aimed at characterizing the effects of dietary l-carnitine supplementation on hepatic fatty acid (FA) metabolism during inflammation in mid-lactating cows. Fifty-three pluriparous Holstein dairy cows were randomly assigned to either a control (CON, n = 26) or an supplemented (CAR; 27) group. The CAR received 125 g rumen-protected product per cow day (corresponding 25 l-carnitine/cow day) from d 42 antepartum (AP) until end trial 126 postpartum (PP). Aside supplementation, same basal diets fed dry period and lactation all In mid lactation, each was immune-challenged by single intravenous injection 0.5 μg LPS/kg BW 111 PP. Blood samples collected before after LPS administration. mRNA abundance total 39 genes related FA assessed liver biopsies taken −11, 1, 14 relative (d PP) also AP as individual covariate using microfluidics integrated fluidic circuit chips (96.96 dynamic arrays). addition concentrations 3 selected proteins metabolism, acetyl-CoA carboxylase α (ACACA), 5′ AMP-activated protein kinase (AMPK), solute carrier family member 20 (SLC25A20) capillary Western blot method −11 1 11 CON. On LPS, differences between CON limited acyl-CoA dehydrogenase (ACAD) very-long-chain (ACADVL) with greater than fat content decreased remained lower level both groups. One challenge, carnitine palmitoyltransferase (CPT1), CPT2, ACADVL, ACAD short-chain (ACADS), 22 5 (SLC22A5) observed group compared However, noncatalytic subunit gamma (PRKAG1), medium-chain (ACADM), ACACA, binding (FABP1) LPS. Two weeks groups no longer detectable. altered pointed increased transport into mitochondria systemic AMPK SLC25A20 neither changing time nor treatment ACACA only affected time. conclusion, temporally some mitochondrial biogenesis very-low-density lipoprotein export response inflammatory but largely lacking 2 wk