v. taghizadeh

This study was aimed to examine the impact of different levels of dietary nucleotides (Vannagen) on serum biochemical and blood parameters of Persian sturgeon (Acipenser persicus). Fish (42.37± 2.12 g and 23.67± 0.61 cm) were divided into four treatments with different levels of dietary nucleotides (, 0.25, 0.35 and 0.5 percent of diet). There were three replicates with a density of 12 fish per tank. After 1 weeks of feeding, serum biochemical and blood parameters were measured. Among the measured factors, blood glucose, triglycerides, cholesterol, erythrocyte and heterophil showed significant differences between the groups fed with nucleotides and the control group (P ≤ 0.05). By increasing the nucleotide levels, the mean heterophil and serum glucose showed significant increase and decrease, respectively. The highest and lowest values of cholesterol and triglyceride were found in groups fed with 0.25% and 0.35% nucleotides, respectively. The other measured factors had no significant difference (P≤0.05). Therefore, it could be said that with regard to the limited capacity of cells to synthesize nucleotides, external preparing of nucleotides could result in the production of needed nucleotides and an increase of its production speed, especially during stress. Such preparation can also improve fish physiology and health status.

This experiment was conducted in order to compare the effect of feed form (pellet vs. mash), dietary nutrient density and metabolizable energy (min vs. max requirement) on performance of broiler chicks. For this purpose, growth response of eight hundred Ross 308 male broiler chicks was evaluated in a completely randomized design with a factorial 2×2 arrangement (2 factors including pelleted form and dietary nutrient density each at two levels), and eight replicates for each treatment. A number of 25 birds were allocated to each treatment. Results of this experiment showed that high level of nutrient and metabolizable energy density and also feed pelleting significantly increased weight gain (P<0.05). Feed dietary nutrient and metabolizable energy density affected feed intake in the first and third week of ages (P<0.05). Increasing of dietary nutrient density did not affect feed conversion ratio, but pelleted form of feed significantly improved feed conversion ratio during whole period of experiment (P<0.05). Birds fed with pelleted diet had higher mortality than those fed with mash diet. Dietary nutrient density had no effect on meat yield cost, but pelleted of feed resulted in decrease of meat yield cost. The result of experiment showed that feeding birds with pelleted diet and high level of nutrient and metabolizable energy would improve performance of broiler chickens.