Determination of apparent digestibility coefficients in 6-, 12- and 18-week-old ostriches

1. The apparent digestibility coefficients (ADC) of a diet consisting of a concentrate and of alfalfa grass in a 4:1 ratio were measured in 6, 12-and 18-week-old ostriches. 2. These coefficients were measured in 4 animals eating ad libitum using both a total collection method, and internal marker methods with acid detergent lignin (ADL) and with acid insoluble ash (AIA). 3. The ADC of dry matter, organic matter, crude protein, ether extract and energy were not influenced by the age of the ostriches. The ADC of structural carbohydrates, however, were significantly higher (P<0.01) in the 12-and 18-week-old animals. 4. The results obtained by the total collection and ADL methods were similar. The AIA method, however, overestimated the values due to the very high marker recovery rate (128.0%).