Abstract:
Two growth assays were conducted to determine the effects of novel carbohydrate
sources in Phase I and II starter diets on
growth performance. In Exp. 1, 90 weanling
pigs (avg initial body wt of 12.4 lb and 18 d
of age) were used in a 38-d trial evaluating
three carbohydrate sources: corn, tapioca, and rice flour. The carbohydrate sources
were substituted for corn in diets formulated
to 1.55 and 1.3% lysine for Phase I (d 0 to
10) and Phase II (d 10 to 24), respectively.
All pigs were fed the same sorghum-soybean
meal-based diet from d 24 to 38 post-weaning.
For the overall experiment, pigs fed rice flour had greater average daily gain (ADG) compared with those fed tapioca, with those fed the diet containing corn having intermediate ADG. Pigs fed rice flour had
improved feed to gain ratio (F/G) compared with those fed either corn or tapioca. In
Exp. 2, 60 weanling pigs (avg initial body wt
of 8.6 lb and 17 d of age) were used in a
similar study to evaluate corn, ground sorghum, and roasted sorghum as the primary
carbohydrate sources in Phase I and II diets.
During d 0 to 10 post-weaning, pigs fed the
corn diet had greater average daily feed
intake (ADFI) than those fed the sorghum-based diets; however, no other differences in
growth performance were observed during the experiment. These results suggest similar
growth performance of starter pigs fed tapioca, sorghum, and roasted sorghum compared with those fed corn-based diets. However, pigs fed rice flour had improved F/G compared with those fed either corn or tapioca. Therefore, decisions on the use of novel carbohydrate sources in Phase
I and II starter diets should be based on their price and availability relative to corn.