Short communication: Responses of Black Neck ostrich chicks to L-carnitine dietary supplementation during the pre-starter growth period

The objective was to determine the growth responses of Black Neck ostrich chicks to different dietary levels of L-carnitine in pre-starter diets. Thirty-two day-old ostrich chicks were randomly divided into four treatments with four replicates, each containing two chicks. All birds received the same basal diet supplemented with 0 (T0, control), 125 (T125), 250 (T250) or 600 (T600) mg L-carnitine per kg. Responses were monitored over three growth phases, 0 - 15, 16 - 30 and 31 - 60 days, the total period being 60 days. T600 had the lowest live weight (LW) and live weight gain (LWG) over the 60-day treatment period. Live weight and LWG values of T125 and T250 did not differ from those of T0. T600 had the worst feed conversion ratio (FCR) during the different stages (0 - 15, 16 - 30 and 31 - 60 days) and over the total 60-day period. Feed intake (FI) was reduced significantly in the T125 and T600 treatments compared to T0 and T250 treatments over the total period. The treatment, T125, showed the lowest FI and FCR responses over the total period, whereas there was no difference between T0 and T250. The results suggest that supplementing the pre-starter diet with 125 mg/kg of L-carnitine can improve the performance of ostrich chicks by decreasing the FCR. In contrast, the suppressive effect of a high inclusion level (T600) might indicate that ostrich chicks are sensitive to a high level of inclusion that could cause adverse effects.