Effects of prebiotic Immunogen on growth performance, intestinal bacteria colonization, and survival rate in Rutilus frisii fry

This study was carried out to determine the effects of Immunogen as a prebiotic on growth related parameters and gut micro-flora in R. frisii fry. A basal diet was formulated using common feed ingredients supplemented with Immunogen at 0, 1, 1.5, and 2 g.kg-1 leading to four experimental diets. Fish were randomly distributed in 500 L fiberglass tanks (1×1×0.5 m). The experiment lasted for eight weeks and the water temperature ranged between 21-24 °C. R. frisii fry with an initial weight of 300 ± 1.7 mg and were randomly distributed in the experimental tanks. At the end of the experiment, growth performance, feed efficiency, and gut micro-flora were assessed. Results showed that inclusion of 1g.kg-1 Immunogen improved final weight, feed conversion efficiency (FCR), and specific growth rate (SGR) (p<0.01) in the fry. A larger survival rate of R. frisii fry was observed at 1 g kg-1 prebiotic inclusion level (p<0.01). However, body protein, fat, and ash were not influenced by prebiotic inclusion. Supplementation of 1 g.kg-1 prebiotic increased the total count of bacteria (p<0.05), but bacterial count did not change at 1.5 and 2 g.kg-1 prebiotic inclusion compared to control diet. In conclusion, Immunogen administration of 1 g. kg- 1 is capable of improving the nutrients efficiency and performance of R. frisii fry through growth stimulation of beneficial intestinal bacteria

Short communication: The effect of feed ingredients on the settling velocity of feces in tilapia (Oreochromis niloticus L.)

Knowledge on the solid waste characteristics is valuable to set up a proper facility in order to increase the removal efficiency and also to understand the factors influencing waste quality. There are two main methods to evaluate removal efficiency of solids generated from a fish farm: feces recovery percentage and settling velocity of feces. Both the recovery efficiency and settling velocity of particles generally have a direct relationship to the weight and size of particles (the heavier the particle, the faster the deposit). Manipulation of diet composition alters fecal physical properties improving feces consistency and leading to a higher recovery and a larger particle size

Effect of different Alphamune levels in artificial diet on growth parameters, digestibility and enzyme activity of rainbow trout, Oncorhynchus mykiss (Walbaum 1792)

This study was conducted to evaluate the effects of Alphamune, a mixed prebiotic composed of mannan-oligosaccharide and β-glucans, on the growth performance, digestibility and enzyme activity of rainbow trout, Oncorhynchus mykiss. A basal diet was formulated using common feed ingredients supplemented with Alphamune at 0, 0.5, 1, 2, and 4 g.kg^-1 leading to five experimental diets. Obtained results showed that inclusion of dietary Alphamune significantly increased the final weight and weight gain (p0.05). Also apparent digestibility coefficient (ADC) was not affected by dietary addition of the prebiotic (p>0.05). Our results indicated that amlayse and lipase activities were not significantly influenced by administration of different doses of Alphamune. The result also showed that trypsin activity was gradually increased with increasing of the probiotic level (p>0.05). In conclusion, inclusion of the prebiotic Alphamune can improve the nutrient efficiency and growth performance of rainbow trout confirming the positive effect of a mixture of prebiotics on fish

Full replacement of fishmeal by poultry by-product meal in rainbow trout, Oncorhynchus mykiss (Walbaum, 1972) diet

Along the plant ingredients, rendered animal protein sources such as blood meal, meat and bone meal and poultry by-product meal have potential to be replaced by fishmeal in rainbow trout feed. Therefore, the main objective of the present study is to determine the effect of full replacement of fishmeal by poultry by-products meal (PBM) on fish performance, nutrient digestibility and also liver characteristics in rainbow trout. Four experimental diets were formulated to contain graded levels of PBM at 0 (control diet), 33 (PBM33), 66 (PBM66) or 100% (PBM100), respectively. The four treatments were randomly assigned to each of 12 tanks, having three replicates for each treatment. Rainbow trout juveniles with an average initial weight of 50±0.42g were reared for two months. The fish gained lower weight and specific growth rate at PBM 66% and 100%. FCR was recorded larger for rainbow trout feeding on PBM 66% and 100% in comparison to PBM 33% and control diets (p<0.05). The whole exchange of fishmeal by PBM (PBM100%) reduced dry matter, fat and protein digestibility (p<0.05). An increase in PBM content of diet also resulted in larger fat content of the fish liver (p<0.05). Body fat content reduced and moisture content increased by increasing PBM level (p<0.05). In conclusion, PBM can be included in rainbow trout feed as an alternative for fishmeal up to 33%. A larger fat content of liver at PBM 100% may indicate a negative impact of PBM on rainbow trout health at full replacement level

The effects of different grain sources on gut evacuation rate and nutrient digestibility in common carp, Cyprinus carpio

The main objective of this study was to investigate whether dietary cereal grains of different carbohydrate sources can change nutrient digestibility, evacuation rate and the number of bacterial colony in gut. Common carp with an average weight of 244.7±6.3 g were divided randomly into sixteen 500-L tanks with a stocking density of 18 fish per tank. Four experimental diets were formulated by inclusion of four cereal grains (wheat meal, barley meal, corn meal and rice meal) in a basal diet in a ratio of 40%. The four experimental treatments with four replicates were assigned in 16 tanks. Inclusion of different types of cereal grain affected growth related parameters in C. carpio. Corn and wheat diets led to larger weight gains and better feed conversion ratios compared to barley diet (324 and 321 versus 305 g for final weight; 1.93 and 1.90 versus 2.25 for fed conversion ratio). Protein and dry matter digestibility in the common carp fed rice diet were lower in comparison to other cereal grains (73 and 58 versus 79-82 and 67-70%). The maximum and minimum bacterial colony numbers (133 and 63 cfu.gr-1×10-7) were observed in fish fed wheat and corn diets, respectively. Evacuation time showed a delay by feeding on barley diet and almost all dry matter left in part I of the intestine after 30 min (first sampling), but this rate was recorded 70% for corn diet .In conclusion, although dietary grains change evacuation time and bacterial colonial number in common carp, this condition does not have a great impact on nutrient digestibility

The effects of different levels of Beta Plus on growth performance, microbial flora and blood parameters of Caspian trout, Salmo caspius (Kessler, 1877)

This study was conducted to evaluate the effects of Beta plus probiotic, a mixture of Bacillius leicheniformic and Bacillius subtilis, on the growth performance and intestinal microbial flora of Caspian trout (Salmo caspius). A basal diet was formulated and supplemented with Beta plus at 0, 0.5 and 1 g kg-1, leading to three experimental diets. Each experimental diet was randomly assigned to quadruple 1500 L tanks. The Caspian trout with an initial weight of 108.7 ± 1.8 g were randomly distributed in the experimental tanks. The results showed that inclusion of dietary Beta plus significantly increased the final weight and specific growth rate (SGR) of Caspian trout compared to those the control treatment. The feed conversion ratio (FCR) was also improved significantly after probiotic administration to the experimental fish. However, the body composition and blood parameters were not influenced by the probiotic inclusion. Total count of Gram positive and negative bacteria in the intestine of the fish increased by feeding on diet contained 1 g kg-1 Beta Plus (P<0.05). In conclusion, administration of the probiotic Beta plus can improve the nutrient efficiency and growth performance of Caspian trout confirming the positive effect of a mixture of Bacillus spp

Effect of Lactobacillus plantarum probiotic and different levels of soybean meal on growth and intestinal histomorphometry in rainbow trout diet

The present study was performed to examine the effects of probiotic addition to diet containing soybean meal (SBM) on growth and intestinal histomorphometry of rainbow trout. A total of 300 fry with mean initial weight of 20.05 ± 0.20 g were distributed to 12 tanks for 90 days. Experimental diets were included control (SBM 0 + probiotic 0), SBM 0 + probiotic 1, SBM 20% + probiotic 0, SBM 20% + probiotic 1, SBM 40% + probiotic 0 and SBM 40% + probiotic 1. On the 30th day, the highest body weight increasing rate (BWI %) and specific growth rate (SGR) were observed in diet containing SBM 0 (0 and probiotic 1) and SBM 20% + probiotic. On the 60th day, adding probiotic to SBM 0 and SBM 20% led to the highest BWI (p < 0.05). The lowest values of final weight, BWI (%) and SGR were achieved in SBM 40% without probiotic (p<0.05). Feed efficiency ratio was elevated in diets containing SBM 40% (p<0.05). On the 90th day, final weight, final length and SGR were highest in fish fed SBM 0 (0 and 1 probiotic) and SBM 20% containing probiotic (p<0.05). According to intestinal histomorphometry, on the 60th day, the highest villus height was found by supplementation of probiotic to SBM 0 (p<0.05). Epithelium thickness was significantly reduced by increasing SBM level to 40% (p<0.05). The greatest mucous thickness and goblet cells were observed  in SBM 0 (0 and 1 probiotic) and SBM 20% containing probiotic groups (p<0.05). According to results on the 90th day, villus height was significantly decreased by SBM level increasing (p<0.05). Epithelium thickness, mucous thickness and goblet cell in diet containing SBM 40% were lower than those in the other treatments (p<0.05). Considering present study, addition of probiotic to SBM 20% is beneficent to improve growth rate and intestinal histology

Effects of adding dietary Lactobacillus plantarum on efficient performance of soybean meal in the rainbow trout (Oncorhynchus mykiss) hematological and immune indices

In the present study, the effects of probiotic (0 and 1) in rainbow trout fed with different levels of soybean meal (SBM; 0, 20 and 40%) were evaluated on hematological and immune indices. A total of 300 fry with average initial weight of 20.05 ± 0.20 g by density of 25 fish per tank assigned to 12 tanks for 90 days. Blood was taken from fish on days 0, 45 and 90, afterward hematological and immune indices were estimated. According to hematological results in day 45, fish fed with SBM 0 demonstrated greatest number of white blood cells and hematocrit among treatments (p < 0.05). In day 90, the highest number of red blood cells was found in SBM 0 and SBM 20% containing probiotic (p < 0.05). Number of white blood cells significantly increased by adding probiotic to different SBM levels (p < 0.05). Hematocrit and hemoglobin concentrations decreased in fish fed with SBM 40% (p < 0.05). In addition, there were interaction between SBM × probiotic in white blood cells on day 90 (p < 0.05). According to immunological results in day 45, neutrophil burst activity (NBT) was elevated by adding probiotic to SBM levels (p < 0.05). The IgM and C3 levels were significantly enhanced by adding probiotic to SBM 0 and SBM 20%. In day 90, the highest NBT value was observed in SBM 0 (probiotic 0 and 1) and SBM 20% containing probiotic among groups (p < 0.05). Addition of probiotic to SBM 0 and SBM 20% caused the elevated lysozyme, IgM, C3 and C4 values (p < 0.05). Furthermore, interaction between SBM levels and probiotic indicated significant effects on NBT after 90 days (p < 0.05). It could be revealed from the current study that L. plantarum compensated some adverse effects of SBM replacement on blood and immune indices by enhancing immunity, hence higher replacement of SBM is not suggested without using probiotic

Effects of lysophospholipid on utilizing different sources and levels of carbohydrate in rainbow trout (Oncorhynchus mykiss) diet

The aim of the present study was to investigate the effects of dietary lysophospholipid and carbohydrates (rye and corn meal) on growth performance, blood and biochemical parameters in rainbow trout. So, 480 fish (6.70 ± 0.99 g in weight) were fed with experimental diets containing 100 g/kg corn, 250 g/kg corn, 100 g/kg corn + 9 g/kg lysophospholipid, 250 g/kg corn + 9 g/kg lysophospholipid, 100 g/kg rye, 250 g/kg rye, 100 g/kg rye + 9 g/kg lysophospholipid and 250 g/kg rye + 9 g/kg lysophospholipid in triplicate. The experimental design was a 2 × 2 × 2 factorial arrangement. Results of growth performance demonstrated elevating in final weight, specific growth rate and feed intake in Tcorn100+lyso and Tray100+lyso, whereas Tcorn250+lyso and Tray250+lyso contrarily led to lower growth performance (p<0.05). Also, RBC and hematocrit indicated interaction effects between diet × lysophospholipid and lysophospholipid × carbohydrate level (p<0.05). RBC and hematocrit were elevated in Tcorn100+lyso and Tray100+lyso (p<0.05). Comparative results of biochemical parameters showed reaction effects of cholesterol between diet × lysophospholipid (p<0.05). Cholesterol values reduced by adding lysophospholipid to different levels of rye and corn and also higher value was observed in Tcorn100+lyso and Tray100+lyso compared to Tcorn250+lyso and Tray250+lyso (p<0.05). It seems that rainbow trout has potency of using 250 g rye and corn in diet containing fat powder without lysophospholipid, while lysophospholipid negatively affects this level of carbohydrates. However, lysophospholipid helps enhancing growth and erythropoiesis in the levels of 100 g rye and corn