Optimum Lactose: Sucrose Ratio for the Pigs Weaned at 21 Days of Age

A total of 240 weaned pigs (BW 5.4 kg) were allotted in a completely randomized block design to find out the optimum lactose : sucrose ratio for the weaned pigs. Treatments were 100:0 (A), 75:25 (B), 50:50 (C), 25:75 (D) and 0:100 (E) in lactose : sucrose ratio. For the first week after weaning, average daily gain (ADG) and feed/gain (F/G) were improved (p < 0.05) for pigs fed A, B and C diets compared to pigs fed diets D and E, but the average daily feed intakes (ADFI) of the pigs were not different. From d 7 to 14, no significant differences was found in ADG and ADFI among the treatments, but pigs fed the diets A, B and C had improved F/G compared with the pigs fed diets D and E (p < 0.05). From d 15 to 21, no significant differences were found in ADG, ADFI and F/G among the treatments. The digestibility of nutrients was not influenced by the lactose : sucrose ratio except nitrogen. Nitrogen digestibility of A diet was significantly higher than D and E diets (p < 0.05) but no significant differences were found among diets A, B and C. Dry matter and phosphorus excretions were not influenced by the treatments. The pigs fed diets A, B and C excreted significantly less nitrogen than the pigs fed diets D and E. In conclusion, the results suggest that sucrose can effectively replace up to 50% lactose in starter diets.