s. yeganeh

Resilience is a concept presented in the context of positive psychology and has a special place, especially in the fields of developmental psychology, family psychology, and mental health. This study aimed to predict resilience based on self-esteem, self-compassion, and mindfulness in the conditions of public quarantine of Coronavirus. In this descriptive-correlational study, 174 individuals who entered the psychological services clinic in Qazvin from October to February 2020, simultaneously with the third wave of Coronavirus outbreak and mandatory quarantine declaration, were selected by purposeful sampling. After obtaining informed consent, the scales of resilience, self-esteem, self-compassion, and mindfulness were used to collect information. Data were analyzed using descriptive statistics, Pearson’s correlation coefficient, and multivariate regression. There was a significant positive relationship between resilience and self-compassion, mindfulness, and self-esteem (F=139.24, p<0.01). The results of multivariate regression analysis indicated that variables of self-esteem and self-compassion could predict resilience with β=0.37 and β=0.59, respectively (p<0.01); and mindfulness could not predict resilience (p>0.05). The results showed that self-esteem and self-compassion were associated with resilience in quarantined individuals; and mindfulness was not related to resilience. Therefore, in order to increase the resilience of the society in the post-Corona conditions and similar critical conditions such as communicable diseases or natural disasters, teachings related to self-compassion and self-esteem can be helpful.

In this study, trypsin was extracted from the viscera of yellowfin sea bream (Acanthopagrus latus) and used as an additive in Sobaity sea bream, Sparidentex hasta, larvae microdiet. The microdiet was supplemented with the extracted enzyme and its efficiency was evaluated in the growth performance of S. hasta larvae. There were five treatments containing zero (control), 1000, 1500, and 2000 IU/kg of the extracted trypsin with 500 IU/kg of a commercial diet of porcine trypsin. S. hasta larvae (mean initial weight of 0.021±0.001 g) were fed with experimental diets for 28 days. Fifteen round polyethylene tanks (300 L, a water volume of 100 L) equipped with a water circulation system and an air stone were used for the treatments. The highest body weight gain (BWG), specific growth rate (SGR), daily growth, survival rate, and protein efficiency ratio (PER) were observed in the larvae fed the diet containing 2000 IU/kg trypsin (p<0.05). In addition, the lowest and the highest values of the feed conversion ratio (FCR) vs daily feed intake and trypsin activity were significantly recorded in 2000 IU/kg trypsin and the control groups, respectively (p<0.05). A positive correlation was observed between the increasing levels of trypsin in the microdiets and growth performance (i.e. BWG, SGR, daily growth rate, survival rate, and PER). Besides, the dietary addition of external trypsin reduced the values of FCR, daily feed intake, and trypsin activity in the larvae. Overall, trypsin at different doses, particularly at 2000 IU/kg, can significantly improve the performance and feed utilization of S. hasta larvae.

The aim of the present study in the first stage was encapsulation of peptides produced from hydrolysis of shrimp wastes (by neutrase enzyme) with combined coating of nanoliposome and chitosan in the form of four treatments (NP or peptide-carrying nanoliposomes, NP-CH-0.05, NP-CH-0.1 and NP-CH-0.5 or peptide-carrying nanoliposomes with coating of 0.05, 0.1 and 0.5% chitosan). In the next step, physicochemical and antioxidant properties of the treatments were investigated. The results showed that average particle size and particle dispersity index in different treatments varied from 228.9±4.85 to 436.7±1.08 nm and 0.389±0.01 to 0.453±0.01, respectively. Zeta potential in nanoliposomes shifted to positive values with increasing chitosan concentration and from -62.59±4.36 mV in NP reached to +56.94±3.71 mV in NP-CH-0.5. Encapsulation efficiency improved by adding chitosan to the surface of nanoliposomes and the highest amount was found in NP-CH-0.5 treatment (94.12±3.73%). Evaluation of release profiles of treatments in Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF) showed that coating of peptides using nanoliposome and chitosan helped in protecting the structure of peptides and reduce their release rate significantly (p<0.05). Chitosan-coated nanoliposomes showed more antioxidant activity than NP treatment. Also in chitosan-coated treatments, with increasing chitosan concentration, antioxidant activity of the treatments increased significantly (p<0.05). According to the results, coating bioactive peptides with combined coating of nanoliposomes and chitosan is a suitable technique to protect and increase the efficiency of peptides.

The aim of this study was to investigate the effect of using hydrolyzed protein (HP) prepared from rainbow trout viscera in the fish diet on its shelf life in terms of chemical spoilage, bacterial load, and chemical composition at ambient temperature. HP was prepared from rainbow trout viscera using Alcalase (1.5% v/w, 55°C, pH 8.5). Five experimental diets were prepared to contain different levels of HP (0, 5, 10, and 20 g of HP/kg) and one diet containing 200 mg/kg of butyl hydroxytoluene (BHT). The prepared treatments were kept at 25±3°C for 18 weeks. The lowest mean TBA index was observed in the feeds with 20 g/kg of HP and Butylated hydroxytoluene (BHT) treatment (p˂0.05). The lowest Total volatile basic nitrogen (TVB-N) index was measured in HP-containing treatments until the 14th week (p˂0.05). The lowest bacterial count was measured in the HP-containing treatments from the 4th week to the end of the experiment (p˂0.05). The highest total protein content belonged to the HP-containing treatments. The highest fat content was recorded in HP-containing and BHT treatments (p˂0.05). According to the results, the addition of HP (20 g/kg) is recommended to maintain the quality of fish feed.

The main objective of this study was to evaluate the pathogenicity of isolated Yersinia ruckeri from Caspian trout. Y. ruckeri specimens were isolated from infected rainbow trout farms located in north of Iran. The identification was confirmed by biochemical tests and 16s rRNA gene sequencing. The pathogenicity test was carried out to determine the virulence of the Y. ruckeri by IP injection, and histopathological and hemato-biochemical changes were evaluated pre and post challenge. Based on the results, LD50 were calculated as 1×105 CFU ml-1, while 1×107 CFU ml-1 caused 100% mortality after 10 days in the experimental groups. The main histopathological changes were seen in liver, kidney, spleen and intestine, including erosion and necrosis, infiltration of inflammatory cell, hyperplasia and catarrhal enteritis in the infected organs. Also, a significant decrease in glucose, RBC counts, Hb values and HCT percentage and significant increase in the WBC counts, neutrophils percentage, AST, ALP and LDH values were observed in infected fish after challenging. Finally, Caspian trout is susceptible to Yersiniosis and can play important role in transmission of Y. ruckeri to cultured and wild fish.

The Ichthyophthirius multifiliis is one of the most important protozoan pathogens of farmed and wild fish populations. In this study, histopathological effects of gamma-irradiated trophonts of I. multifiliis coated with alginate nanoparticles in rainbow trout gill were evaluated. Therefore, after adaption period the fish with mean weight 30 g were distributed to 4 groups: Two groups were treated with gamma-irradiated trophonts of I. multifiliis and coated with alginate nanoparticles, gamma-irradiated trophonts of I. multifiliis. One group was infected with active trophonts of parasite as positive control. In negative control group, no treatment was used. On day 30, gill tissue from treated, infected and control fish was analyzed for evaluating the histopathological alterations. The results showed that the use of alginate nanoparticles formulated in gamma-irradiated I. multifilis trophonts can significantly decrease severe hyperplasia, sub-epithelial edema, and fusion of the secondary lamellae, focal and multifocal necrosi in gill. Also, gamma-irradiated trophonts of I. multifiliis coated with alginate nanoparticles induced an increase in amount of the gill macrophages in treated fish. Therefore, the alginate nanoparticles can be in leading development of safe and efficient gamma-irraditad trophonts deliver tool in rainbow trout with more useful behavior and fewer side effects on gill tissue.

This research investigated the feasibility of using three strains Lactobacillus sp. viz. AM11, AM13, and AM14 previously isolated from dairy products to be used as probiotics in fish diet for phytase production. The bacteria grown in oxygenated media, bile salt, acid and supernatant of digestive tract  were examined for their antibiotic resistance and non-pathogenicity for using in fish feed. Results indicated that the isolates might be attractive candidates as probiotic strains in rainbow trout. All strains were capable of growth and produced phytase in a pH range from 3.0 to 8.0. The isolated strains were also resistant in bile salts and supernatant of digestive tract. No mortality has been observed in the fish injected by bacterial strains. No bacterial growth has observed in the liver, kidney and spleen media after 24 h. Therefore, the examined Lactobacillus strains were non-pathogenic. Due to the low resistance of these strains to tetracycline (antibiotic), it is suggested to avoid using tetracycline in rainbow trout farms when the bacterial strains are used as probiotic. According to the results, the three isolated resistant strains can be employed as probiotics in fish feed.

Different hormones are used to induce final sexual maturation in fish breeders and one of these hormones is different analogue of gonadotropin releasing hormone (GnRH) with different trade names. The aim of this study was to evaluate the biological activity of recombinant GnRH produced in the laboratory of Sari Agricultural Sciences and Natural Resources University on the induction and synchronization of ovulation in goldfish broodstock (Carassius auratus).  For this purpose, 20 pairs of mature goldfish were obtained from goldfish breeding centers and transferred to wet laboratory of the Fisheries Department. Fish were acclimated to experimental conditions for 2 weeks then they were divided to 4 treatments. The first, second and third groups received 10, 15 and 20 μg recombinant GnRH/kg body weight, respectively, as well as 20 mg metoclopramide (anti-dopamine)/ kg body weight and control group was injected by physiological saline with 20 mg metoclopramide (0.09% NaCl.) The results showed that the produced recombinant GnRH had the ability to induce final maturation in the studied broodstock and all groups received recombinant GnRH ovulated but none of the control group ovulated. The latency period in the broods injected by dose of 20 μg/kg was significantly lower than the other treatments (p<0.05). There was no significant difference in the total obtained egg and relative fecundity between treatments of recombinant GnRH (p<0.05). The results indicated that the recombinant GnRH has a good biological activity and it can be introduced as a suitable alternative for the treatment of reproductive disorders in goldfish.

240 Caspian brown trout (Salmo caspius) fingerlings with initial weight of 13.74±0.63 g were stored in 300 L tanks to investigate the effect of starvation and refeeding on compensatory growth and digestive enzymes activity. The fish were introduced to four different periods of starvation during 10 weeks including control (with no starvation:C), 2 weeks (S2), 4 weeks (S4) and 6 weeks (S6) and then fed to satiation during the refeeding period. Sampling for growth and enzymes activity measurements was conducted three times: day 1 (T1), after starvation (T2), after 2 weeks (R2) and 4 weeks (R4) of refeeding. Results have indicated a significant decrease in growth performance after starvation (p<0.05). Final weight (W2) was similar to the control group in treatment of S2 after 2 weeks of refeeding. Body weight increasing (BWI) and specific growth rate (SGR) were the highest in treatment of S6 at the end of trial (p<0.05). Trypsin, chymotrypsin, lipase and amino peptidase declined after starvation while pepsin activity significantly increased in deprived fish (p<0.05). Trypsin and chymotrypsin values were lower in S6 than of control whereas the lowest activity of pepsin was observed in the control fish. After 4 weeks of refeeding, trypsin and chymotrypsin values were similar to that of the control (p>0.05). Generally, results declared that Caspian brown trout fingerlings could recover digestive capacity after 2 weeks of starvation by appropriate refeeding with no negative impact on growth performance.

The goal of this study was to detect polymorphisms in Insulin like growth factor-I gene of Persian sturgeon fish (Acipencer persicus) using PCR-SSCP technique and also to investigate their association with fish growth traits (condition factor, body length & weight). In this research, 95 Persian sturgeons were randomly selected and fin clip for DNA extraction were taken from caudal fin. DNA was extracted using modified salting out method and two fragments of 171 and 362 bp in 5/-UTR and 3/-UTR regions of IGF-I gene were amplified, respectively. Genotyping of individuals showed three different banding patterns of M, K and G for the fragment of 171 and 362 bp with the frequency of 13, 39, 48 and 31, 49, 20 percent in Persian sturgeon samples, respectively. The genotype K at 3/-UTR and genotype M at 5/-UTR marker site were the most frequent genotypes. Marker-trait analysis using SAS statistical software indicated no significant association between observed banding patterns of marker loci and growth traits in Persian sturgeon. Considering the important role of IGF-I as a probable candidate gene effective on growth related traits, survey of this marker sites are recommended for larger-size populations

In this study, for the first time in Iran, the effect of edible coating of sodium alginate and whey protein in combination with innclulated cultivation of Pediococcus acidilactici and Lactobacillus plantarum bacteria on rainbow trout fillets was studied. Accordingly, chemical indicators such as pH, TVB-N, TBA and microbial laod at 0, 7, 14 and 21 days of refrigeration storage at 4C were investigated. Results showed that in all samples pH, TVB-N and TBA increased over time. In terms of microbial parameters, probiotic coating could reduce the number of TVC in coated fillets on day 21 compared to control treatment. However, the TVC level in all treatments at the end of the storage period was higher than the allowable range for human consumption (P<0.05).  The number of LAB also increased during the storage period and there was a significant difference in coated treatments compared to control (P<0.05).  The highest changes were observed in control treatment and the lowest changes were related the coated treatments. Overall, using higher percentages of sodium alginate containing probiotic bacteria can be recommended for better preservation of the fillet during the refrigerated storage.