Ileal digestibilities of neutral detergent fiber, crude protein, and aminoacids associated with neutral detergent fiber in wheat shorts for growing pigs

An experiment was carried out to determine the ileal digestibility values o f NDF, CP, and AA associated with NDF in different samples of wheat shorts consisting of different proportions of wheat bran, shorts, and flour, herea fter referred to as wheat fractions. Six barrows (average initial BW 37.2 k g, and fitted with a simple T-cannula at the distal ileum) were fed one of six experimental diets, formulated to contain 17% CP (as-fed basis), accord ing to a 6 x 6 Latin square design. Diets A, B, C, D, and E contained 17.53 % soybean meal (SBM), which contributed 50% CP to these diets. The diets co ntained shorts, bran, or flour alone or in combination, contributing the re maining 50% CP to these diets. The proportions of shorts, bran, and flour i n the wheat fractions were 70% shorts and 30% bran in diet A, 85% shorts an d 15% bran in diet B, 100% shorts in diet C, 85% shorts and 15% flour in di et D, and 70% shorts and 30% flour in diet E. Diet F contained 35.05% soybe an meal, which provided the sole source of dietary CP. Chromic oxide was us ed as a digestibility marker. During the first experimental period, the dai ly dietary allowance was provided at a rate of 5% (wt/wt) of the average BW . Thereafter, the allowance was increased by 100 g at each successive perio d. Each experimental period comprised 12 d. Following a 7-d adaptation peri od, feces were collected for 48 li and ileal digesta for a total of 24 h. T he contribution of CP and AA associated with NDF gradually decreased from w heat fraction A to E, reflecting a decrease in NDF content from 42.3 to 29. 5%. Of the indispensable AA in wheat fraction A, the contributions ranged f rom 12.9 to 15.9%. In wheat fi-action E, these values ranged from 9.0 to 11 .3%. The ileal digestibility values of NDF ranged from 11.8% in diet E to 1 7.1% in diet C (P > 0.05). There were usually no differences (P > 0.05) in the ileal digestibilities of AA associated with NDF between the wheat fract ions. However, with the exception of lysine and tyrosine, there were negati ve correlations (P < 0.05) between the apparent ileal AA digestibilities an d the content (%) of CP associated with NDF in the wheat fractions. Further more, there was no effect (P > 0.05) of the diets containing wheat fraction s on the recovery of bacterial protein and mucin in ileal digesta.