Long-term feeding study on disodium 5-ribonucleotide in dogs.

Groups of 4 male and 4 female Beagle dogs were fed for 2 years on diets containing 0 (control), 0.1, 1.0 and 2.0%, respectively, of disodium 5'-ribonucleotide (a 50 : 50 mixture of disodium 5'-inosinate and disodium 5'-guanylate). The mean daily intakes of the 3 test groups ranged during the experiment from 0.04-0.03, 0.48-0.26 and 0.93-0.51 g/kg, respectively. No effects attributable to treatment were found in mortality, food consumption, water consumption, bodyweight gain, ophthalmoscopy, clinical signs, haematology, serum chemistry (other than allantoin levels), organ weights, macroscopic pathology or histology, Small differences were observed between mean values in treatment and control dogs for serum allantoin but there was no indication of any persistent significant difference throughout the 2-year study. In a 6-week preliminary test, dietary levels of up to 10% disodium 5'-ribonucleotide were without detectable adverse effect upon beagle dogs of either sex.