Long-term effects of early-life dietary L-carnitine on lymphoid organs and immune responses in Leghorn-type chickens

Summary The long‐term effects of supplementing Leghorn‐type chickens with dietary L‐carnitine after hatching for 4 weeks on growth, lymphoid organ weights, humoral and cell‐mediated immune responses were assessed in a 12‐week study. A commercial starter feed supplemented with 0 (control), 100 (LC) or 1000 (HC) mg L‐carnitine/kg was offered to day‐old ISA Brown cockerels for 4 weeks, then all birds were given a commercial pullet grower feed for another 8 weeks. No differences (p > 0.05) in growth rates, feed intake or feed utilisation efficiency existed among the dietary treatments throughout the study. Compared with control birds, HC‐fed birds had a lower (p