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  Simple and corresponding impacts of organic acidifiers ( Lactic acid, Acetic Acid and Citric acid) with three levels( 0%,0.25% and 0.5 %) on specific volume and dough  fermentative parameters was conducted by a completely randomized design with factorial arrangement and three replications. At the next stage an orthogonal comparison between selected acidified treats (having control sample) with sourdough treats was made. The study showed that addition of each of these acidifiers had a significant effect on the mentioned property. Also statistical analyses revealed that, corresponding impacts of all the three acidifiers on the feature was significant (P<0/05). Finally the studies distinguished that type and amount of acidifiers used in this study don’t have any bad impact on the structure of dough gluten, so that the increase of acidity of these samples resulted in increase of bread specific volume .Also, orthogonal comparison between selected acidified treats (having control sample) with sourdough group indicated that considering specific volume property, these two groups did not show any significant differences.

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The present study intends to assess the effects of Na diformate oral use with citric acid on some skin mucosal immunity indices (total protein, total immunoglobulin (TIg), lysozyme, protease, esterase, and alkaline phosphatase (ALP)) of rainbow trout following experimental challenge with Yersiniosis agent (Yersinia ruckeri). Subsequent to the determination of the 7-day median lethal dose (LD50) of Yersinia ruckeri, fish were stocked in eight groups and two repetitions. The acidifiers separately with a dose of 0.2%, and combined 0.1+0.1% was added to the commercial diet. Five days after inoculation, feeding of fish with acidifiers commenced, and following 15 days, the mucus samples were gathered from the skin of anesthetized fish to measure immune indices. Results showed that the 7-day LD50 of Y. ruckeri was 8.91×105 CFU/ml. In the main experiment, findings indicated the significant effect of Na diformate on the increased levels of mucoid total protein and proteolytic activity of healthy or diseased fish. The acidifiers-contained diet because of potentially having synergistic effect caused inducing the mucus TIg. It seems that the orally use of Na difirmate in 0.2% of the diet separately or combined with citric acid, at least for 15 days, can improve the cutaneous mucus immunological indices that its result is an increase in the survival rate of farmed rainbow trout.