In the weaning period, transition from sow's milk to the post-weaning diet causes the withdrawal of important nutrients as milk nucleotides, wich are known to be determinant for the development of the gastrointestinal tract and inmune function. The objective of these investigations was to study the effect of including these nucleotides in solid diets for piglets. Nucleotide composition of sow's milk was analyzed using 5 sows at 21d of lactation. The average free nucleotide concentration was 102.8 ± 9.16_mol/100 mL. Two experiments were performed to assess the effects of a product based on this composition (Nucleoforce Piglets ®) on digestive adaptation and incidence of diarrhoea of nursery piglets. In Exp. 1, three groups of 6 piglets were weaned at 21 days of age and fed with a diet supplemented with 0 (control), 1000 or 2000 ppm of nucleotides, and a fourth group of 6 piglets were maintained in lactation. Seven days after weaning, piglets were euthanized and samples of jejunal mucosa were processed for histological measurements. Villus height decreased from 448µm in un-weaned pigs to 275µm in the control group 7 days after weaning.

Although there were no differences in feed intake among groups, the reduction in villous height was less pronounced (P<0.001) in nucleotide supplemented groups showing a villous height of 351 and 378µm with the doses of 1000 or 2000 ppm respectively (figure 1).

In Exp. 2,384 early weaned pigs were fed during 14 days with a diet supplemented with 0 (control), 750 and 1000 ppm of nucleotides. ADG and ADFI were not modified by the treatment, but nucleotide supplementation reduced the number of pigs treated with antibiotic as a result of diarrhoea (15,63% vs 3,13% 1,56%; for control, 750 and 1000 ppm; P<0.001; Table 1).