عنوان مقاله [English]
To assess the effects of dietary nucleotide on structure of pyloric caeca in Salmo trutta caspius, 315 juvenile fish with average weight of 12.26g (average length 11.12cm) were fed with dietary nucleotide (NT) and a control diet for 8 weeks (0.25% NT, 0.5% NT and 0% as control). To investigate the changes of pyloric caeca structure, 6 fish specimens from each treatment fixed into Bouin solution for histological examinations. Then, the sample was placed in paraffin, and 4mm sections of samples were provided and after coloration were investigated for histological features. The investigation demonstrated that both NT-supplemented diets had significant effects (P<0.05) on thickness of enterocyte, villi length, number of enterocyte cell and thickness of pyloric caeca muscle. However, between the two treated groups, changes of enterocyte and sub mucosa, length and number of villi were non-significant (P>0.05). However, the group receiving 0.25% NT showed more positive effects on enterocyte cell number and thickness of muscle layer compared with those treated with 0.5% NT.