When l-carnitine was injected in eggs from Single Comb White Leghorn hens, in a 0.05 to 10 µmol/egg (0.008 to 1.612 mg/egg) dose range on d 17 or 18 of incubation, it was shown to have no effect on hatchability or subsequent hatching chick BW (Zhai et al.,2008a).