JOURNAL OF FISHERIES SCIENCE AND TECHNOLOGY (JFST)
Year:2019 | Volume:8 | Issue:2 |Papers Count:7

Aims: The purpose of the present study was to hydrolyze Sardinella sindensis protein isolate by pancreatin enzyme and then fractionation hydrolysate based on molecular weight and finally evaluating and comparing the anti‐ oxidative and anti‐ diabetic properties of the fractions with hydrolysate. Materials & Methods: Protein isolate from Sardinella sindensis muscle was extracted and then hydrolyzed using pancreatin enzyme in two enzyme/substrate ratio of 2. 5 and 5% (W/W) for 2h. The hydrolysates were fractionated into three fractions included FPH‐ I (<2kDa), FPH‐ II (2‐ 10kDa) and FPH‐ III (>10kDa) using an ultrafiltration (UF) membranes. The antioxidant and anti‐ diabetic activiteis of the fractions and hydrolysate were investigated. Findings: The degree of hydrolysis increased with increasing hydrolysis time and it was significant between 30 and 60 minutes (p<0. 05). FPH‐ III showed the highest DPPH radical scavenging activity. In terms of chelating activity on Fe2+, there was no significant difference between the fractions and hydrolysate (p>0. 05). Also, FPH‐ III showed a better ABTS radical‐ scavenging activity. FPH‐ III had the highest inhibitory potential against α ‐ amylase at 2. 5%. In addition, the inhibitory effect of samples at 20mg/ml against α ‐ glucosidase was less than 50%. Conclusion: FPH‐ III from Sardinella sindensis protein isolate by pancreatin enzyme had the highest DPPH radical scavenging, ABTS+ activity and alphaamylase inhibitory.

Considering the high nutritional value of fish meat and low consumption of fish in Iran, it is always advisable to consume this meat and its products. Cyprinus carpio is one of the most important and widely used species among fish. In the present study, Cyprinus carpio meat with beef meat (red meat) was used in the production of different samples of non-fermented sausages in ratios of 5, 15, 25, 35, 50, 65, 75, 85, and 95% in combination and on the day after production, physicochemical tests such as moisture, protein, fat, and ash content, and organoleptic evaluation such as color, aroma, flavor, consistency, and overall acceptance carried out on the samples. The results showed that by increasing the proportion of fish meat in the formulation, protein content increased and fat, ash, and moisture content decreased. The proportions of 35 to 65% of 􀏐 ish meat received the highest score, while, the proportions of 5 to 35% and 5 to 50% showed the highest scores of aroma and 􀏐 lavor, respectively. Treatments with a ratio of 65 to 95% of 􀏐 ish meat had the highest score of consistency. The overall acceptance of treatments showed that the ratios of 35 to 65% of 􀏐 ish meat showed the highest scores.

Aims: Transportation of live fish is a common practice among aquaculture facilities. Different studies have reported how transport elicits physiological stress responses and increases disease susceptibility in farmed fish. The aim of the present study was to evaluate the hematological parameters in common carp juvenile feeding of Bacillus sp. probiotics in the condition of before and after long-distance transports. Materials & Methods: In this experimental study, 180 common carp juveniles with a mean weight of 40± 1. 89g were randomly divided into 2 􀏐 iberglass tanks with a capacity of 400L. Fish juveniles in one tank were feeding with Protexin were used at a concentration of 1×107CFU/100g and 􀏐 ishes in the other tank were not consumed probiotic (control group) for 45 days. At the end of the feeding trial, the carp juveniles from both treatments randomly were packed in plastic bags (40L) at a density of 1kg/bag. The juvenile feeding previously from probiotic were packed in 2 treatments with 0/05g NaCl/or without of NaCl in water. Also, the juvenile feed of the control tank was packed in bags as the control. The bags unpacked after 12h and blood samples were taken from 10 fish in each replicate and hematological parameters were compared among the groups. Findings: WBC, Hematocrit, Hemoglobin, MCV, MCH, MCHC, and leukocytes differential count are affected by after transport stress (p<0. 05). However, there were no significant differences in the amounts of RBC and hemoglobin in experimental treatments (p>0. 05). Conclusion: Feeding of common carp juveniles with Bacillus sp. probiotics had positive effects on blood parameters before and after long-distance transportation in plastic baggage, thereby if used in diet, it can be good alternatives to salt.

Aims: In the present study, the apparent digestibility of protein and amino acids of ten types of plant and animal feed ingredients as the main sources of protein was evaluated in the Siberian sturgeon diet (290± 22g). Materials & Methods: Feedstuffs included fish meal, meat and bone meal, poultry by-product meal, blood meal, feather meal, soybean meal, rapeseed meal, wheat gluten, corn gluten, and bakery yeast. The dietary treatments included reference diet and ten different experimental rations (30% of the target feed ingredient and 70% of the reference diet). Chromic oxide was used as an indigestible marker in dietary feed. A group of 165 Siberian sturgeons stocked into 33 tanks with 500 liters volume and fed with test diets (3 replicates per diet). Findings: At the end of the experiment, the highest and lowest protein digestibility was observed in 􀏐 ish meal (92. 87%) and poultry by-product meal (59. 96%), respectively. Also, the highest level of amino acid digestibility in fish meal was measured (90. 9% and 88. 13% for total essential and non-essential amino acids, respectively). The lowest digestibility of the essential amino acids was reported in rapeseed meal (65. 5%) and non-essential amino acids in poultry powder (60. 68%). Conclusion: Fish meal, meat and bone meal, poultry by-product meal, corn gluten, and wheat gluten were identified as feed ingredients with high protein and amino acids digestibility for Siberian sturgeon.

In the present study, 20 pieces L. vannamei shrimp, with average weight 5. 53± 0. 02g were fed in 500-liter tanks with three replicates during 8 weeks. At the end, the intestines of shrimps were fixed in Bouin's solution for classic histology by hematoxylin-eosin and green light and for immunolocalization of the Na+/K+-ATPase enzyme (sodium-potassium pump) by immunohistochemistry methods. The midgut epithelium was covered by simple columnar cells and nucleus position was in basal region of cells and Na+/K+-ATPase enzyme observed in basal region of cells. Evaluation of rectal pad large lobes deep in foldings and distance between the lobes were observed. Lumen was observed in the middle of rectal pad and apical lobes were evident and columnar cells in the marginal in foldings with basal nucleus were observed. Small appendage called posterior diverticulum was located in primary and in upper region of rectal pad. This region was tubular and its cells with basal nucleus were observed. Rectum was located in distal region of hindgut. This region was a short muscular tube and lined with a simple columnar epithelium with low infoldings and apical nucleus in these cells were observed. The sodium-potassium pump was located in the baso-latral area in all regions of hindgut cells. The use of hematoxylin-eosin and green light is an appropriate method to separate different parts of intestine in vannamei shrimp and also immunohistochemistry is a suitable method for Na+/K+-ATPase enzyme localization.

Aims: In the present study, the effect of spearmint extract in different concentrations was investigated on chemical and bacterial quality of common kilka surimi during storage in the refrigerator (4± 1° C) at different times. Materials & Methods: In the present study, chemical tests including peroxide value (PV), thiobarbituric acid (TBA), total volatile bases nitrogen (TVB-N), pH and total viable count (TVC) and psychrophilic count (PTC) as bacterial tests were assessed. Findings: Over time, the PV index decreased significantly in SE treatments compared to the control treatment as it was increased at 4% SE from 0. 33 on the 􀏐 irst day to 4. 08m eq O2 on the 12th day (p<0. 05). The TBA and TVB-N amounts were increased in the control so that it was recorded 0. 43mg malondialdehyde for TBA and 32. 8mg N for TVB-N on day 15 with a signi􀏐 icant difference compared to those containing SE (p<0. 05). The pH value was significantly lower in groups treated with SE than the control treatment during the whole storage period (p<0. 05), with an increase from 6. 28 at day 1 to 7. 10 at day 15 for 4% SE (p<0. 05). The TVC and PTC bacteria from control were significantly higher than those from treated groups with SE wherein TVC and PTC bacteria were increased in the control treatment from 3. 55 and 3. 25 to 6. 64 and 5. 96 log cfu/g, respectively (p<0. 05). Conclusion: Based on the 􀏐 indings of the present study, 4% SE can be used for short-term storage of the common kilka surimi at temperature of refrigerator.

an aquaculture practice, feeding rates were examined in different life stages of Beluga sturgeon. Materials & Methods: Feeding rates were 5, 7, 9, 11, 13, and 15% in stage 1, 2, 4, 6, 8, 10, and 12% in stage 2, 1. 5, 2, 2. 5, 3, and 3. 5% in stage 3 and 1. 5, 1. 75, 2, 2. 25, and 2. 5% in stage 4. Farming durations of stages 1 to 4 were 10, 10, 42, and 56 days, as well as initial mean weights were 1. 85, 7, 112. 04, and 300. 54g, respectively. Findings: Optimum feeding rates from growth and feeding parameters point of view were 9 and 5%, respectively, in stage 1. In stage 2 also optimum feeding rates were different from growth and feeding point of view, as they were 4 and 2%, respectively. For both aspects of growth and feeding parameters, optimum feeding rate was 2. 5% of body weight in stage 3. In stage 4, the lowest food conversion rate was observed in the feeding rate of 1. 5% and there were no significant differences among treatments from growth parameters point of view. Conclusion: Growth and feeding parameters were affected with feeding rates in stages 1, 2, and 3. In stage 4, feeding rates in􀏐 luenced feeding parameters but had no significant effects on growth performance.