جستجوی مقالات مرتبط با کلیدواژه "پروتئین تک یاخته" در نشریات گروه "شیلات"

The aim of this study was to evaluate fish meal replacement by a bacterial single cell protein (IPL68) on growth performance, digestive enzymes activity (protease, lipase and α-amylase), gut histology and gut microbiota in rainbow trout fry (initial weight = 2.51 ± 0.55 g) for 6 weeks. Five diets were formulated with different bacterial SCP level (0:D1, 25:D2, 50: D3, 75:D4 and 100: D5 %) to replace fishmeal protein. At the end of the trial, body weight gain, specific growth rate, condition factor and hepatosomatic index showed the higher values than other diets with a significant differences (P<0.05). The food conversion ratio had the lowest and highest values in D3 and D5 diets, respectively, with a significant difference (P<0.05). The survival rate in all experimental diets was 100%. The highest activity of protease, lipase and α-amylase enzymes was observed in the intestines of fish fed with D3 diet, which showed a significant difference compared to D4 and D5 diets (P<0.05). The highest number of total bacteria and lactic acid bacteria was observed in diet D3, which was significantly different from other diets (P<0.05). The highest villus height (µm) and the ratio of villus height to crypt depth was observed in fish fed with D3 diet, which was not significantly different from D1, D2 and D4 diets, but showed a significant difference with D5 diet (P<0.05). Based on the obtained results, D3 diet can be suitable for the growth of rainbow trout fry compared to other diets.

In this study the effects of replacing fish meal with yeast (Saccharomyces cerevisiae) on feeding and growth in rainbow trout (Onvorhynchus mykiss) fry were analyzed. The experiments of this study were conducted for a period of 10 weeks during summer 2019 in a fish farm located in Chahar-Mahal and Bakhtiari Province (Iran). In treatments used in this study, different ratios of fish meal and yeast were used in production of experimental fish food plates: 1) only fish meal, 2) 66% fish meal and 33% yeast, 3) 66% yeast and 33% fish meal, and 4) only yeast. Based on the results of this study the first two treatments in which only fish meal and 66% fish meal plus 33% yeast were included as animal protein sources were significantly better compared to the 3rd and 4th treatments regarding growth indices (mean final weight, specific growth rate, and condition factor). There were no significant differences observed among treatments for hepatosomatic and visceral indices (P>0.05). The best food conversion ratio (FCR), protein efficiency ratio, and food efficiency were observed in treatments 1 and 2, which differed significantly from other treatments (P<0.05). The total feed consumption by each individual and the total daily food consumption were not significantly different among treatment used in this study (P>0.05). In conclusion, it can be proposed that replacement of 25-50% fish meal with yeast in fish feed plates can provide a more economic fish food.

In this study, body composition and digestive enzymes activity was assessed in rainbow trout fry (weight 2.51 ± 0.55 g) fed by bacterial single cell (BSC) as a dietary protein source replaced with fish meal as completely randomized design with triplicate for 6 weeks. Experimental diets were prepared in 5 treatments as isonitrogenous with different levels of fish meal and BSC (100% fish meal (A), 75% fish meal and 25% BSC (B), 50% fish meal and 50% BSC (C), 25% fish meal and 75% BSC (D) and 100% BSC (E)). The body composition findings showed that the highest amount of lipid and protein and the lowest amount of moisture and ash was revealed in fish fed by diet C while the lowest amount of lipid and protein and the highest amount of moisture and ash was observed in fish fed with diet E (P <0.05). Enzymatic assessment from pyloric caeca and intestine were showed that trypsin and α-amylase were increased significantly in fish fed by diet C while alkaline phosphatase activity had the highest amount in diet D than did that from diet E (P <0.05). Based on the results of this study, it is recommended that BSC could be properly replaced up to 50 % with fish meal in rainbow trout fry diet.

The present study was conducted to evaluate the effect of fish meal replacement with single cell protein on growth performance and proteolytic enzymes activity of pepsin, trypsin and alkaline protease in rainbow trout (Oncorhynchus mykiss) fry (weight: 2.51±0.55g) for 6 weeks. Five experimental diets were prepared with replacement levels of 0 (A), with 25% (B), 50% (C), 75% (D) and 100% (E) of fish meal with microbial protein as isonitrogenous and isoenergetic. Parameters of body weight gain, relative growth rate, protein, lipid and feed efficiency ratio in diet C were significantly the higher than other treatments (p<0.05), while feed conversion ratio was shown the highest and the lowest values in diet C and E, respectively , with a significant difference than those from other treatments (p<0.05). The survival rate was 100 % in the diets. The highest activity of trypsin and alkaline protease enzymes from pyloric caeca and intestine was observed in diet C, which showed a significant difference compared to D and E diets (p<0.05). Also, pepsin had significantly the highest activity in C diet than that from other diets exception for B diet (p<0.05). The findings of growth performance and pepsin, trypsin and alkaline protease activity were revealed the diet containing 50% single cell protein could be appropriate for rainbow trout growth.