Effects of dietary carbohydrate levels on growth, survival and body composition in Caspian Kutum (Rutilus frisii kutum, Kamenskii, 1901)

This study was carried out to evaluate the effects of dietary carbohydrate levels on growth performance and body composition of juveniles Caspian Kutum (Rutilus frisii kutum). Fish with initial average weight of 0.8±0.2g (±SD) were fed five isoproteic and isenergic formulated diets with different carbohydrate levels including 15, 20, 25, 30 and 35% in triplicate groups, 4 times daily according to their satiation for 10 weeks. Results showed that increasing the level of carbohydrate to 35% significantly increase some growth indices such as final weight (Wf), weight gain (WG), body weight increase (BWI), specific growth rate (SGR) and protein efficiency ratio (PER). In addition, result of body composition analysis showed that the increase in carbohydrate level lead to increase of protein level. So, the highest amount of protein was observed in fingerlings fed with diet containing 35% carbohydrate. In conclusion, the results indicate that increase in carbohydrate levels from 15 to 35% have not any negative effect on growth parameters and therefore, the level of 35% carbohydrate in the diet of 1-2g Caspian Kutum fingerlings can lead to better efficient in protein and desirable growth

Effect of different levels of Azolla meal on growth performance and digestibility of common carp (Cyprinus carpio)

In this study, the effects of different dietary levels of Azolla meal were investigated on growth performance and digestibility of common carp (Cyprinus carpio) fingerlings during 60 days. Five experimental diets approximately iso-protein (30%) and isolipidic (10%), were formulated with different levels of Azolla meal consisting of 0, 15, 25, 35 and 45%, respectively. In each experimental treatment, triplicate groups of common Carp fingerlings (16.5± 0.2 g) were used in a completely randomized design. Twenty fish were assigned to each experimental unit and stocked in 300 L tank. The results showed that the use of Azolla meal up to 15% had no negative effect on growth performance. The growth of fish was reduced significantly with increasing Azolla meal level of more than 15% of diet. Based on results, the apparent digestibility coefficients (ADC) of dry matter decreased with increasing Azolla meal in diets. The highest ADC of protein was observed in control treatment. However, no significant difference was observed between the treatment 2 (diet with 15% Azolla meal) and control (without Azolla meal) for ADC of protein. In general, results of the present study showed that Azolla meal can be used up to 15% in Cyprinus carpio diet

Effect of dietary supplementation of sodium butyrate on growth performance, survival rate and carcass composition of beluga, Huso huso

In the present study, the effects of sodium butyrate as a dietary supplement on growth performance, survival rate and carcass composition of beluga, Huso huso were evaluated. After acclimatizing to the rearing conditions feeding with the basal diet for a week, five experimental diets containing 0, 0.1, 0.2, 0.3, 0.4 and 0.5% (T0, T0.1, T0.2, T0.3, T0.4 and T0.5) sodium butyrate were examined on 360 juvenile beluga (average weight 15 ± 0.59 g) for 8 weeks. The studied fish were randomly transferred to 18 experimental 3200-L tanks and a dewatering volume of 1000 L (20 fish per tank). At the end of the trial, growth indices (final weight, weight gain, weight gain percentage, condition factor, specific growth rate, protein efficiency ratio), survival rate (%) and carcass composition were measured. The results showed that sodium butyrate supplementation influenced the growth performance, survival rate and carcass composition of the examined fish. The best growth performance and survival rate were observed in T0.3 (p<0.05). In addition, feed conversion ratio and feed efficiency in T0.3 were significantly better than the control group (p<0.05). Carcass protein of fish in T0.3 was significantly higher, while carcass fat was significantly lower than the control group (p<0.05). Overall, this study showed that 0.3% sodium butyrate supplement in the diet can enhance the growth performance, survival rate and carcass composition in juvenile beluga

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 microencapsulated Lactobacillus rhamnosus JCM 1136 probiotics on blood parameters and body composition of rainbow trout

Effects of the microencapsulated Lactobacillus rhamnosus JCM 1136 on the blood parameters and body composition of rainbow trout (Oncorhynchus mykiss). In this study, first the probiotic bacteria L. rhamnosus JCM1136 were microencapsulated with coatings of sodium alginate and chitosan. Then, they were added to the food pellets and given to the fingerlings. For this purpose, 225 rainbow trout fingerlings (6.23 ± 0.17 g) in 5 treatments and each treatment with 3 replications were placed in California trays (220 × 30 × 15 cm). Treatment 1 (T1): Fish fed with 108 CFU/g microencapsulated probiotics with sodium alginate, treatment 2 (T2): fish fed with 108 CFU/g microencapsulated probiotics with sodium alginate and chitosan, treatment 3 (T3): fish fed with 108 CFU/g capsule-free probiotics, treatment 4 (T4): fish fed with probiotic-free sodium alginate-chitosan capsules and control treatment 5 (T5): fish fed with commercial free-probiotic and capsules pellets. At the end of the course, results indicated that the fishes fed with diet containing sodium alginate-chitosan microencapsulated probiotics in terms of blood parameters such as red blood cells, white blood cells, hemoglobin and hematocrit as well as the amount of carcass protein compared to control and other treatments were in better condition, which These differences were significant with control treatments fishes (p < 0.05)