A study of multiple
tissues was conducted to identify potential
metabolic differences in cattle differing in feed efficiency. Individual
feed intake and body weight was measured on 144 steers during 105
days on a high-concentrate ration. Steers were selected according
to differences in average daily gain (ADG) with those with the greatest
ADG (
n
= 8; 1.96 ± 0.02 kg/day) and least ADG
(
n
= 8; 1.57 ± 0.02 kg/day), whose dry matter
intake was within 0.32 SD of the mean intake (10.10 ± 0.05 kg/day).
Duodenum, liver, adipose, and longissimus-dorsi were collected at
slaughter, and metabolomics profiles were performed by ultra performance
liquid chromatography quadrupole-time of-flight mass spectrometry.
Principal components analyses,
t
-tests, and fold
changes in tissues profile were used to identify differential metabolites
between ADG groups. These were primarily involved in α-linolenic
metabolism, which was downregulated in the greatest ADG as compared
to least-ADG group in duodenum, adipose, and longissimus-dorsi. However,
taurine and glycerophospholipids metabolisms were both upregulated
in the greatest ADG compared with least-ADG group in the liver. The
phospholipids and cholesterol were quantified in the tissues. Lipid
transport and oxidation were the main common metabolic mechanisms
associated with cattle feed efficiency. Combining analyses of multiple
tissues may offer a powerful approach for defining the molecular basis
of differences in performance among cattle for key production attributes.