AUC	Area Under the Curve
BBCM	Bifidobacterium animalis + Lactobacillus animalis in Milk Replacer
BCAAs	Branched-Chain Amino Acids
CIL	Chemical Isotope Labeling
CLP	Lactobacillus plantarum
CMLP	Combination of CLP and BBCM
CON	Control Treatment
CS	Calf Starter
DFMs	Direct-Fed Microbials
FC	Fold Change
KEGG	Kyoto Encyclopedia of Genes and Genomes
LC–MS	Liquid Chromatography–Mass Spectrometry
MR	Milk Replacer
MS	Mass Spectrometry
MSI	Metabolomics Standards Initiative
PLS-DA	Partial Least Squares–Discriminant Analysis
ROC	Receiver Operating Characteristic
TSP	Total Serum Protein