EFFECTS OF DIETARY OLIGOSACCHARIDES ON THE GROWTH-PERFORMANCE AND FECAL CHARACTERISTICS OF YOUNG GROWING PIGS

The effects of dietary fructo-oligosaccharides (FOS) and trans-galacto -oligosaccharides (TOS) were studied on growth performance and faecal characteristics of young growing pigs. FOS and TOS are non-digestible oligosaccharides (NDOs); they are not hydrolyzed by enzymes of endogen ous origin, but are readily available as substrate for the gastrointes tinal microflora. Dietary levels of NDO-rich products were 7.5 and 15 g kg(-1) diet for FOS, and 10 and 20 g kg(-1) diet for TOS. NDOs were included in an experimental corn-based control diet, which was low in NDOs (190 mg raffinose kg(-1)) and contained no additional copper, ant ibiotics or probiotics. NDO-rich products were included at the expense of glucose and purified cellulose. Resulting five experimental diets were fed ad libitum to 9-week old castrated male piglets (n = 10) with an initial body weight (se) of 15.6 +/- 0.3 kg. Rigs had received the control diet for 19 days before reaching this body weight. Individual body weights and feed refusals were recorded every 3-4 days during si x weeks. Fresh faeces were rectally collected at day(0), day(14), and day(35), and analyzed for NDOs, pH, and dry matter content. Dry matter intake and body weight gain of the NDO-fed pigs were lower than the c ontrol pigs (P = 0.039 and P = 0.031, respectively) in week one throug h three. Dietary NDOs did not affect mean growth performance in week o ne through six. FOS and TOS could not be detected in the faeces. Dieta ry NDOs did not affect faecal pH. Faecal pH increased with time (P < 0 .01). NDO-fed pigs had a lower faecal dry matter content than control pigs (P = 0.062). Pigs fed TOS-rich diets had a lower faecal dry matte r content than pigs fed FOS-rich diets (P = 0.061). It is concluded fr om this experiment that exchanging cellulose for NDOs in young growing pigs' diet results in a temporary depressed feed intake with little o r no effects on faecal dry matter content and pH. (C) 1998 Elsevier Sc ience B.V.