243 Effects of Initial Nursery Diet Budget on Growth Performance of 5.5- to 23-kg Pigs

Abstract An experiment was conducted to determine the effects of the initial nursery diet budget on growth performance. A total of 3,264 pigs (initial BW = 5.5 kg), placed in pens with 51 pigs each, were used in a 45-d trial. There were 4 treatments consisting of different feed budgets of the initial nursery diet: 4.1 kg, 5.4 kg, 6.8 kg, or 8.2 kg. The experimental diet was corn, soybean meal, and whey permeate-based and contained 1.38% SID Lys. After the allocated budget was consumed, pigs were provided a common corn and soybean meal-based diet. There were 16 replicates per treatment. Pigs were weighed weekly to calculate ADG, ADFI, and G:F. Data were analyzed with SAS MIXED procedure. In the first 14 d of the trial there was no evidence for differences (P > 0.10) in growth performance as all pigs were receiving their allocated budget of the initial diet. From d 14 to 21 as well as d 0 to 21, pigs that received a budget of 6.8 or 8.2 kg had improved ADG (quadratic, P < 0.05) and G:F (linear, P < 0.05) compared to those fed budgets of 4.1 or 5.4 kg. From d 21 to 45, when all pigs received a common diet, there was no evidence for differences (P > 0.10) in ADG. However, there was a linear response (P < 0.05) in G:F, with pigs previously fed the lowest feed budget presenting improved G:F. Overall (d 0 to 45), there was an improvement (linear, P < 0.05) in ADG and ADFI as feed budgets increased, with the best performance observed when pigs were fed 6.8 or 8.2 kg of the initial nursery diet. In conclusion, providing a 6.8 or 8.2 kg budget of the initial nursery diet resulted in improved overall nursery performance.