Vitamin A plays a critical role in many essential life processes. In herbivores, it is either derived from plant β-carotene or
directly as a dietary supplement. In cattle, vitamin A has the potential to influence various carcass traits that are sought by specific
beef markets. A group of 20 Angus steers was removed from pasture and fed a low β-carotene and vitamin A cereal-based ration
on a feedlot for 308 days. Ten of the steers were supplemented with vitamin A (retinyl palmitate, 60 IU of vitamin A/100 kg body
weight/day) and the other ten received no supplement. The results demonstrated that restriction of vitamin A intake changed
intramuscular fat deposition without changing subcutaneous fat depots. Angus steers that had been depleted of vitamin A showed
increased intramuscular fat in the longissimus thoracis et lumborum (LTL) by 35% (Pb0.026) and seam fat area at the quartering
site by 33% (Pb0.0273), when compared with cattle supplemented with vitamin A. There were no changes in intramuscular fat in
the semitendinosus. Visually assessed marbling scores were also higher (19%; Pb0.094) in the non-supplemented, depleted group.
There was no effect of vitamin A depletion on cattle growth and other meat traits (eye muscle area, meat colour, pH, meat cut
weight), meat eating attributes (tenderness, cooking loss) or muscle fibre diameter. The only difference (Pb0.0177) among the
meat traits was fat colour where depleted animals had whiter fat than the controls. Moreover, the fat from the vitamin A depleted
group was softer with a lower melting point. We conclude that the reduced vitamin A consumption, leading to vitamin A depletion,
increases intramuscular fat. On the other hand, the vitamin A depletion did not increase subcutaneous fat depth or change other
meat quality traits, suggesting that marbling and these other traits are not invariably related.