Selective enrichment of bifidobacteria in the intestinal tract of broilers by thermally produced kestoses and effect on broiler performance.

A series of kestose oligosaccharides have been produced from pyrolysis of sucrose and the effects of feeding these thermal kestoses on broiler performance and cecal microbial populations were evaluated. Eighty-four broiler chicks (day-old Hubbard x Hubbard) were fed either a nutritionally complete basal starter diet (control), the starter diet dressed with 8% of other sugars found in the thermal kestoses mixture (glucose, sucrose, and fructose), or the starter diet dressed with 10% crude thermal kestoses (2% kestoses, 8% other sugars) for a 4-wk period. Body weight and feed intake were measured weekly. After 4 wk the birds were killed, cecal contents were collected, and selected microbial populations were enumerated. Weight gains were 938, 968, and 989 g for control, other sugars, and thermal kestoses groups, respectively. There were no dietary effects on weight gain, feed conversion, or concentrations of total aerobic bacteria, coliforms, aerobically enumerated lactobacilli, total anaerobes, or clostridia. Cecal bifidobacterial concentrations were increased (P < 0.001) 24-fold in kestose-treated birds compared with controls, with bifidobacterial concentrations being 8.98, 9.09, and 10.36 log10 cfu/g cecal DM in birds fed the control, other sugars, and thermal kestoses diets, respectively. Anaerobically enumerated lactobacilli concentrations in kestose-treated birds were increased (P < 0.007) sevenfold compared with controls, with lactobacilli concentrations being 9.56, 9.53, and 10.36 log10 cfu/g cecal contents, respectively. Thermally produced kestoses altered intestinal bacterial populations in broilers and may have potential to enhance health and performance under the appropriate conditions.