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مقاله علمی – پژوهشی:‌ اثر تریپتوفان جیره در تراکم‌های مختلف پرورش بچه تاسماهی سیبری (Acipenser baerii) بر عملکرد رشد، بقا و برخی شاخص‌های خونی Effect of dietary tryptophan on growth performance, survival and hematological indices of juvenile Siberian sturgeon (Acipenser baerii) at different stocking densities 1 1 هدف از این مطالعه، بررسی تاثیر سطوح مختلف تریپتوفان جیره بر عملکرد رشد و برخی از شاخص‌های خونی بچه تاسماهی سیبری (Acipenser baerii) در تراکم‌های مختلف پرورش بود. بدین منظور، بچه تاسماهیان سیبری با میانگین وزن 10/0±24/10 گرم در دو تراکم پایین (LD؛ 3/1 کیلوگرم در مترمربع) و بالا (HD؛ 6/2 کیلوگرم در مترمربع) با جیره‌های غذایی حاوی تریپتوفان با سطوح صفر (شاهد)، 2/0، 4/0 و 6/0 درصد پروتئین جیره به مدت 12 هفته غذادهی شدند. نتایج تجزیه‌وتحلیل عملکرد رشد در پایان دوره آزمایش نشان داد که تریپتوفان، تراکم‌ و برهم‌کنش آنها بر وزن نهایی، درصد افزایش وزن، نرخ رشد ویژه و میانگین رشد روزانه اثر معنی‌دار داشتند (05/0p≤)، به‌طوری‌که تریپتوفان در سطح 4/0 درصد تیمار کم‌تراکم، دارای بهترین عملکرد بود. همچنین تراکم و برهم‌کنش تراکم و تریپتوفان بر نرخ مصرف غذا، تاثیر معنی‌دار داشتند (05/0p≤)، به‌طوری‌که میزان آن در تریپتوفان 6/0 درصد تراکم بالا در بیشترین سطح بود. تریپتوفان بر ضریب چاقی (CF)، ضریب تبدیل غذایی (FCR) و نرخ کارآیی پروتئین (PER)، فقط در تراکم پایین، اختلاف معنی‌دار نشان داد (05/0p≤). بیشترین مقدار CF در تریپتوفان 2/0 درصد و بیشترین مقادیر FCR و PER در تریپتوفان 4/0 و 6/0 درصد تیمارهای کم‌تراکم مشاهده شد، درحالی‌که در تراکم بالا، تفاوت معنی‌دار مشاهده نشد. تریپتوفان، تراکم و برهم‌کنش آنها بر بازماندگی، اثر معنی‌دار نداشت (05/0p≤). در شاخص‌های هماتولوژیک، تریپتوفان، تراکم و برهم‌کنش آنها بر تعداد گلبول‌های قرمز خون، اختلاف معنی‌دار نشان داد (05/0P≤) که در تیمار کم‌تراکم با تریپتوفان 4/0 درصد، در بیشترین سطح قرار داشت. در تعداد گلبول‌های سفید (WBC)، هموگلوبین (HB) و هماتوکریت (HCT)، در تیمارهای هر دو ‌تراکم، اختلاف معنی‌دار دیده شد (05/0p≤)، به‌طوری‌که بالاترین مقادیر WBC و HB در تریپتوفان 4/0 درصد تیمارهای هر دو ‌تراکم پایین و بالا دیده شد. بیشترین HCT، در تراکم پایین با تریپتوفان 4/0 درصد مشاهده شد. تریپتوفان بر HCT در HD، تاثیر معنی‌دار نداشت. نتایج مطالعه حاضر نشان داد که بهترین عملکرد رشد تاسماهی سیبری در تیمارهای کم‌تراکم تغذیه شده با جیره‎های حاوی 4/0 درصد تریپتوفان نسبت به سایر تیمارها دیده شد، اگرچه جیره‌های حاوی تریپتوفان در عملکرد رشد تیمارهای پرتراکم، اختلاف معنی‌دار نداشت. استفاده از جیره‎های حاوی 4/0 درصد تریپتوفان، در شاخص‌های هماتولوژیک (مقادیر WBC و HB) هر دو تراکم پایین و بالا اختلاف معنی‌دار داشت. بنابراین، کاربرد جیره‌های حاوی تریپتوفان توانست در بهبود پرورش تاسماهی سیبری در شرایط تراکم بالا موثر باشد. 2 Introduction According to world's growing population, one of the most important problems is food security. On the other hand, aquaculture is considered one of the important industries for providing protein and food resources worldwide, which has always faced numerous challenges (Pauly and Zeller, 2017). Given the issue of food security, the primary goal of aquaculturists is to achieve higher production. However, one of the most significant problems in aquaculture is the lack of water resources (Falahatkar and Rahdari, 2017). The lack of water resources has led fish producers to use increased stocking density as a solution to improve production. The increase in density can cause stress. One of the ways to achieve much production is to improve formulated diets to enhance the growth and health of fish. Researchers have added tryptophan to the diets of cultured fish to improve growth performance because it has been shown that this amino acid can improve growth performance as a very important economic indicator (Hosseini et al., 2020; Jhon et al., 2024; Zhang et al., 2024). Therefore, the present study was conducted with the hypothesis that growth, survival, and hematological indices in high-density cultured juvenile Siberian sturgeon (Acipenser baerii) would improve with the supplementation of dietary tryptophan. Methodology The study was conducted with 12,000 juvenile Siberian sturgeons with an average weight of 10.24±0.10 g in 8 experimental treatments with three replicates in 24 tanks as follows: Treatments 1 and 2 (fish fed with no dietary tryptophan at densities of 1.3 (LD; low density) and 2.6 kg/m² (HD; high density), respectively), Treatments 3 and 4 (fish fed with diets containing 0.2% tryptophan in the protein at densities of 1.3 and 2.6 kg/m², respectively), Treatments 5 and 6 (fish fed with diets containing 0.4% tryptophan in the protein at densities of 1.3 and 2.6 kg/m², respectively), Treatments 7 and 8 (fish fed with diets containing 0.6% tryptophan in the protein at densities of 1.3 and 2.6 kg/m², respectively). The juvenile sturgeons were fed at 3% of their body weight for 12 weeks. At the end of the rearing period, the fish were weighed and growth indices were measured. Blood samples were taken for hematological analysis. To assess the effects of stocking density and tryptophan levels on growth performance, survival, and hematological indices, a Two-way ANOVA test was used, followed by Tukey's test for comparisons at the P≤0.05 significance level. Results The analysis of growth performance at the end of the experimental period showed that different tryptophan levels, stocking densities, and their interaction had significant effects on WG, BWI, SGR, and DGR (p≤0.05). In all mentioned factors, tryptophan in LD with diets containing tryptophan showed significant differences compared to control and HD. The highest levels of these parameters were observed at 0.4% tryptophan in LD. Results showed no significant differences between treatments fed with different diets containing tryptophan in feed intake, but stocking densities and their interaction had significant effects (p≤0.05). The interaction effect of different tryptophan levels and stocking densities on PER, CF, and FCR showed significant effects of different tryptophan levels and stocking densities on these growth indices, with no significant interaction effect (p≤0.05). While the impact of diets containing tryptophan in LD showed significant differences, this difference was not observed in HD. The interaction effect of tryptophan and stocking density on SR was not significant, and survival rates were 100% in all treatments (p≤0.05). In hematological indices, different tryptophan levels, stocking densities, and their interaction had significant effects on RBC (p≤0.05), with the best performance in LD fed with 0.4% tryptophan. Tryptophan and stocking density had significant effects on WBC, HB, and HCT, with no significant interaction effects (p≤0.05). WBC and HB levels in both density treatments showed significant differences, with the highest WBC in LD with 0.2% tryptophan and HD with 0.6% tryptophan. The highest HB levels were observed at 0.4% tryptophan in both densities treatments. The highest HCT levels was observed at 0.4% tryptophan in LD, while no significant differences were observed in HCT at different tryptophan levels in HD. Discussion and conclusion The results of this study showed the positive impact of using tryptophan on growth performance and increased production in LD. Threre was no significant effect on growth indices in HD. The negative effects of density and stress on growth performance divert the body's micronutrient reserves from their primary function, using for stress response instead of growth, leading to reduced growth (Dabrowski et al., 1996). Additionally, regarding the positive effect of 0.4% tryptophan on hematological indices in juvenile Siberian sturgeon culture, results showed that in LD, using this diet positively affected all hematological indices, promoting the health of Siberian sturgeon. In HD, although tryptophan had no significant impact on RBC and HCT, it positively affected WBC and HB, improving the health of Siberian sturgeon. It appears that improving hematological indices with diets containing tryptophan in HD increases fish tolerance to stress in HD. In general, it can be concluded that providing the necessary amount of tryptophan in the diet is essential for the growth, development and health of Siberian sturgeon at HD by improving hematological indices. Therefore, it is recommended to use 0.4% tryptophan to increase production and improve health conditions in Siberian sturgeon, especially under high density conditions. Conflict of interest The corresponding author, on substitute of all authors of this article, announces that in publishing this article, publication ethics, including plagiarism, research misbehavior, data cheating, or both submission and publication, have been completely avoided, and there are no commercial benefits, and the authors have not received any payment for presenting their work. Therefore, the originality of the content of this article is declared. This work has not been previously published elsewhere and has not been submitted to another journal at the same time. Hereby, it grants permission to the publisher to publish the article and its contents, including text, tables, figures, etc. Acknowledgments We would like to express our gratitude to the Beluga Caviar Fish Farm, International Sturgeon Research Institute and the Faculty of Natural Resources, University of Guilan. 1 17 2025/02/11 1403/11/23 2025/08/1 1404/5/10 معصومه نقیبی Masoumeh Naghibi گروه شیلات، دانشکده منابع طبیعی، دانشگاه گیلان، صومعه‌سرا، ایران Iran m.naghibi83@gmail.com میرمسعود سجادی Mirmasoud Sajjadi گروه شیلات، دانشکده منابع طبیعی، دانشگاه گیلان، صومعه‌سرا، ایران Iran mmsajjadi@hotmail.com محمود محسنی Mahmoud Mohseni انستیتو تحقیقات بین‌المللی ماهیان خاویاری، مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، رشت، ایران Iran mahmoudmohseni73@gmail.com بهرام فلاحتکار Bahram Falahatkar گروه شیلات، دانشکده منابع طبیعی، دانشگاه گیلان، صومعه‌سرا، ایران Iran falahatkar@guilan.ac.ir Sturgeon Nutritions Amino acid Stress ماهیان خاویاری مواد مغذی اسید آمینه استرس Allameh, S.K. 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مقاله علمی – پژوهشی:‌ برآورد میزان تنوع ژنتیکی در ذخیره مولدین فیل‌‌ماهی (Huso huso Linnaeus, 1758) با استفاده از داده‌های حاصل از توالی یابی ژنوم Genomic-based investigation of genetic diversity in broodstock of beluga (Huso huso Linnaeus, 1758) 1 1 فیل‌‌ماهی به عنوان اصلی‌ترین گونه پرورشی از ماهیان خاویاری در ایران مطرح بوده که ذخیره مولدین کنونی آن از تعداد محدودی مولد وحشی در دو گذشته ایجاد شده است. فقدان گونه‌‌های شناسنامه‌دار یکی از مهم‌ترین عوامل محدودکننده در توسعه صنعت آبزی‌پروری ماهیان خاویاری در ایران بوده است. از این‌رو، در پروژه حاضر و برای اولین بار از تکنیک توالی‌‌یابی مبتنی بر ژنوم[1] به منظور برآورد تنوع ژنتیکی و تهیه شناسنامه مولکولی مبتنی بر ژنوم از ذخیره مولدین فیل‌‌ماهی موجود در انستیتو ماهیان خاویاری، استفاده شد. توالی‌‌یابی ژنومی منجر به تولید GB294 داده حاصل از 261974459 خوانش ژنومی شد که در نهایت باعث شناسایی 1836 نشانگر SNP[2] در ژنوم فیل‌‌ماهی شد که بیشترین تعداد آن بر کروموزوم شماره 58 مشاهده شد. نتایج حاصل از تجزیه‌‌وتحلیل SNPs کشف‌‌شده نشان داد که میزان هتروزیگوسیتی موردمشاهده در ذخیره مولدین فیل‌‌ماهی موجود در انستیتو، 35/0 است. همچنین 105 آلل در ذخیره مولدین مورد بررسی یافت شد که بیانگر تنوع آللی مناسب در این گونه بود. نتایج حاصل از روابط هم‌‌تباری با استفاده از مارکرهای SNP شناسایی شده برای اولین بار نشان داد که ذخیره ژنتیکی مولدین فیل‌‌ماهی در انستیتو در دو خوشه ژنتیکی، قابل تقسیم بندی هستند. میزان همخونی در مولدین فیل‌‌ماهی مورد بررسی 02/0 برآورد گردید که این میزان پایین همخونی در کنار ساختار جمعیتی مختلط مورد مشاهده در آزمون PCA می‌تواند بیانگر تنوع بالا در مولدین وحشی ایجادکننده جمعیت حاضر باشد. با توجه به دسترسی بسیار محدود به مولدین وحشی برای غنی‌سازی خزانه ژنی گله‌های پرورشی، پیشنهاد می‌‌گردد تا با استفاده از روش‌‌های نوین مبتنی بر ژنومیکس در زمینه شناسایی خزانه‌های ژنی، حفظ ساختارهای ژنتیکی و تکثیر هدفمند بر اساس اطلاعات ژنتیکی در بازسازی ذخایر و آبزی‌پروری اقدام گردد.   [1] Genotyping-by sequencing [2] Single nucleotide polymorphism (SNP) 2 Introduction Sturgeons (Acipenseriformes) are of the most commercially and scientifically important fish species in the globe. These fish are mostly anadromous, spending most of the life cycle in the marine and brackish waters and migrating to the freshwater rivers to spawn (Kottelat and Freyhof, 2007). The Caspian Sea basin has been the main refuge for six species of sturgeons namely Huso huso, Acipenser persicus, Acipenser stellatus, Acipenser guldenstaedtii, Acipenser nudiventris and Acipenser ruthenus, all of which under critically endangered level of the IUCN red list (IUCN, 2025). Generally speaking, the number of sturgeon species has declined, and the beluga (H. huso) is currently in the most critical situation due to a decline in the number of adults leading to local extinctions of the wild populations (Dudu et al., 2014). It is worth noting that female beluga does not spawn every year and the optimal reproductive performance of these fish occurs at an age equivalent to twice the age of first sexual maturity, which can be considered as a limiting factor in the survival of this species considering the shrinking populations (Boscari et al., 2021). Several factors such as overfishing and poaching for trade of caviar and meat, dam construction, loss of nursery grounds, pollution, global warming, and reduced volume of freshwater flowing into the seas are considered to be the most important components in the decline of wild sturgeon populations. In order to compensate the loss of wild populations of H. huso and on the other hand providing the human society required caviar and protein, Iranian Fisheries Organization started the restocking activity since five decades ago and stablished sturgeon aquaculture from two decades ago. Due to the sharp decrease in wild mature beluga of the southern Caspian Sea during the last decades, nowadays most of the aquaculture and restocking activities are forced to be focused on the brood stock generated from few wild parents in the past. Therefore, it is necessary to use modern molecular methods and prepare a genomic-based certificate to protect genetic reserves and enhance the genetic diversity of the native beluga in the south of the Caspian Sea. Genetic diversity represents the variations in the number and type of alleles available in chromosomal loci, which is also considered the main basis for the adaptation of species and populations against changing environmental conditions. While several molecular markers such as SSR, AFLP, and mtDNA, have been widely used during the four decades in fisheries studies (Robledo et al., 2018), these days due to the revolution in the genome sequencing technologies (NGS) more robust genotyping methods such as Genotyping-by Sequencing (GBS) can provide more diverse, sensitive and accurate estimations by screening thousands of variant markers throughout the whole genome of organisms even in species without reference genome (Sonah et al., 2013; Andrews et al., 2016; Barría et al., 2018; Liu et al., 2018). Therefore, during the present study for the first we used a genome-based technique known as GBS in order to estimate the amount of genetic diversity and identify possible genetic nuclei in H. huso brood stock available at International Sturgeon Research Institute (ISRI). Methodology The feeding was stopped a week before sampling and each fish specimen was PIT tagged for later traceability purposes. Caudal fin tissues of 23 Huso huso was sampled and preserved in absolute ethanol for later molecular experiments. DNA extraction was done from the fin tissues through Phenol-Chloroform method with minor modifications (Jafari et al., 2022) and their quality and quantity in terms of DNA integrity, purity and concentration were determined using 0.8% agarose gel and Nano Drop instrument (ND 1000). After DNA samples were qualitatively approved, DNA pellets were sent to Novogene for 150bp PE sequencing on a lane of Illumina Novaseq 6000. Quality of the raw reads generated by sequencing were assessed through Trim Galore (https://www.bioinformatics.babraham.ac.uk/projects/trim_galore/) and only window reads with mean quality of 20 were kept in the final dataset. The clean data set then mapped to the genome reference of Huso huso using Bowtie2 (Langmead and Salzberg, 2012) and the SNP calling was performed based on Stacks. After conducting SNP calling, SNPs were filtered based on parameters such as MAF of 0.05, LD and Hardy-Weinberg equilibrium. Dispersal of fish individuals were visualized using Principal Component Analysis (PCA) based on the two first components in R (Team, 2013). Furthermore, FineRADstructure was used to illustrate the probable genetic clusters based on coancestry information through SNPs (Malinsky et al., 2018). Results The sequence quality analysis showed that the quality of the sequences was high with an average of 92.55. In total, 294 Gb of DNA data obtained from GBS libraries contained an average of 41% guanine (G) and cytosine (C) bases in the genome of Huso huso. PE genomic sequencing produced 261,974,459 reads, with an average alignment of 90% to the reference genome (Table 1). The average number of reads obtained from DNA sequencing in each specimen was about 11 million reads. The results of variant calling showed that a total of 1836 SNP markers with a minimum allele frequency of 0.05 were called from genome sequencing in H. huso with the maximum number of SNPs detected on chromosome 58 (Fig. 1). Based on the results obtained from SNPs obtained from genomic sequencing, the amount of genetic diversity observed in the H. huso broodstock was 0.35. Also, the inbreeding and nucleotide diversity were calculated to be 0.02 and 0.28, respectively (Table 2). The distribution of genetic diversity in the H. huso broodstock using the two first components of PCA is depicted in Figure 2. Based on the results of the PCA, the first two components accounted for 31.89% of the variance. The results of the phylogenetic relationships based on coancecstry relationship also showed that the studied broodstock of H. huso can be considered in two main genetic sub-groups (Fig. 3). Discussion and conclusion Identifying genetic reserves and maintenance of genetic diversity are among the most important measures in managing broodstock either in a sustainable aquaculture activity or in a restocking program. In sturgeons’ aquaculture, there is a particular concern about the reduction of genetic diversity in intensive beluga farming. Preservation of an appropriate level of genetic diversity within the population is of great importance in diminishing negative effects of inbreeding and genetic drift. In the present study, and to the best of our knowledge for the first time in Iran, the identification of genetic groups in the broodstock of Huso huso available at the International Sturgeon Research Institute was carried out using GBS method. Accordingly, creation of a genetic certificate using 1836 SNP markers obtained from GBS was successfully implemented on 23 H. huso. Based on the obtained results from 1836 SNP marker, the observed heterozygosity was 0.36 in the investigated broodstock of H. huso. Observed heterozygosity is the most common indicator of genetic diversity used in determining the genetic health of fish broodstocks. Alongside with the observed heterozygosity, allelic richness should also be taken into consideration in assessment of genetic diversity. Results of the SNP markers showed a considerable number of alleles (An= 105) in the studied broodstock of H. huso, indicating a satisfactory level of heterogeneity in this broodstock. This was also supported by the small value of inbreeding (Fis= 0.02). The UPGMA tree based on coancestry information revealed an admixture pattern of genetic clustering in H. huso. It seems that wild parents from different populations had been used in generating the broodstock of H. huso at ISRI during the past decades. However, based on the genetic clustering heatmap it is suggested to consider two genetic nuclei in the investigated broodstock of H. huso in order to keep the genetic diversity for future sustainable aquaculture purposes. Conflict of interest The authors declare that they have no conflict of interest. Acknowledgment Hereby we wish to appreciate Iranian Fisheries Science Research Institute and Iranian Fisheries Organization for their financial support and also providing laboratory required equipment to conduct the current project. 19 28 2025/02/112025/07/7 1404/4/16 2025/08/12025/08/1 1404/5/10 امید جعفری Omid Jafari انستیتو تحقیقات بین المللی ماهیان خاویاری، مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، رشت، ایران Iran jaafari.omi@yahoo.com ناصر کرمی راد Naser Karamirad سازمان شیلات ایران Iran Naserkaramiradddd@yahoo.com مهدی گلشن Mehdi Golshan مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران Iran Mahdigolshan@yahoo.com علی نقی سرپناه Alinaghi Sarpanah انستیتو تحقیقات بین المللی ماهیان خاویاری، مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، رشت، ایران Iran Alinaghisarpanahhh@yahoo.com مهرشاد زین العابدینی Mehrshad Zeinolabedini پژوهشگاه بیوتکنولوژی کشاورزی ایران، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران Iran Mzeinalabediniii@yahoo.com اسماعیل عبداله زاده Esmaeil Abdollahzadeh انستیتو تحقیقات بین المللی ماهیان خاویاری، مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، رشت، ایران Iran abdolahzadehhhh@rocketmail.com محمد حسن زاده صابر Mohammad Hassanzadeh Saber انستیتو تحقیقات بین المللی ماهیان خاویاری، مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، رشت، ایران Iran meraj.saberrrr@yahoo.com مریم نصراله پورمقدم Maryam Nasrolahpourmoghadam سازمان شیلات ایران Iran Pourmoghadamm@yahoo.com مهدی شکوری Mehdi Shakoori سازمان شیلات ایران Iran mshakouriiiii@yahoo.com محمود محسنی Mahmood Mohseni انستیتو تحقیقات بین المللی ماهیان خاویاری، مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، رشت، ایران Iran mohseniiii@yahoo.com Gene pool Genomics Inbreeding SNP Sturgeons چندشکلی تک‌نوکلئوتیدی خزانه ژنی درون‌آمیزی ژنومیکس ماهیان خاویاری Andrews, K.R., Good, J.M., Miller, M.R., Luikart, G. and Hohenlohe, P.A., 2016. 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مقاله علمی – پژوهشی:‌ سمیت تحت‌‌کشنده حشره‌‌کش دیازینون بر رشد، زنده‌مانی، فعالیت آنزیم‌های آنتی‌‌اکسیدانی و گوارشی پریان میگو (Phallocryptus spinosa Milne-Edwards, 1840) Sublethal toxicity of the Diazinon insecticide on the growth, survival, antioxidant and digestive enzymes activity of Fairy shrimp (Phallocryptus spinosa) 1 1 آلودگی محیط‌‌زیست در اثر استفاده از حشره‌‌کش‌‌ها در فعالیت‌‌های کشاورزی، تهدیدی جدی برای بوم‌‌سازگان‌‌های آبی محسوب می‌شود که می‌تواند چرخه زندگی و ذخایر زیستی بسیاری از گونه‌های زی‌‌شناوران جانوری (ریزسخت‌‌پوستان) را تحت تأثیر قرار دهد. از این‌رو، در مطالعه حاضر اثر سمیت حشره‌‌کش دیازینون بر رشد، زنده‌مانی، فعالیت آنزیم‌های آنتی‌‌اکسیدانی و گوارشی در پریان میگو ( Phallocryptus spinosa) مورد بررسی قرار گرفت. غلظت کشندگی میانی (LC50) برای مرحله‌های ناپلی و بلوغ و در ساعت‌های 24، 48، 72 و 96 با استفاده از تجزیه‌وتحلیل آماری پروبیت تعیین گردید. به‌ منظور بررسی اثر غلظت‌‌های تحت‌‌کشنده دیازینون، میانگین غلظت‌های LC50 96 ساعته استفاده شد و ناپلی‌ها در قالب 4 تیمار شامل گروه شاهد، 25 درصد LC50، 50 درصد LC50 و 100 درصد LC50 به مدت 7 روز پرورش داده شدند. نتایج نشان داد، غلظت‌های مختلف دیازینون باعث کاهش درصد زنده‌مانی و رشد پریان میگو (P. spinosa) در روزهای 3، 5 و 7 پرورش شد (05/0>p). فعالیت آنزیم‌‌های آنتی‌‌اکسیدانی (سوپر اکسید دیسموتاز، کاتالاز و گلوتاتیون پراکسیداز) و محتوای مالون دی‌‌آلدئید در غلظت‌‌های مختلف سم دیازینون افزایش یافت (05/0<p). همچنین سطح فعالیت آنزیم‌‌های گوارشی (پروتئاز، لیپاز و آلفا آمیلاز) نیز در غلظت‌‌های مختلف سم دیازینون افزایش یافت (05/0<p). بر اساس نتیجه‌گیری نهایی می‌توان بیان کرد که حشره‌‌کش دیازینون منجر به کاهش زنده‌‌مانی و رشد و تغییر در فعالیت فعالیت آنزیم‌های آنتی‌‌اکسیدانی، محتوای مالون دی‌‌آلدئید و آنزیم‌‌های گوارشی در پریان میگو (P. spinosa) شد. بنابراین، بایستی در ارتباط با چگونگی مدیریت در دفع پساب‌های آلوده به سموم کشاورزی توجه بیشتری صورت پذیرد. 2 Introduction Population growth and limited production inputs have forced farmers to use pesticides (Zand et al., 2002), and aquatic ecosystems are consistently exposed to these pollutants (Mansingh and Wilson, 1995). Pesticide contamination in aquatic ecosystems poses a serious threat to the foundation of the food chain (Aydın and Köprücü, 2005; De Prado et al., 2012). Pesticides at the chronic level led to destructive effects in various physiological functions (Varo et al., 2002; Koprucu and Koprucu, 2006). Additionally, organophosphorus pesticides have been shown to induce oxidative stress, alter growth rates, and disrupt reproductive indices in the larvae of the shrimp Streptocephalus dichotomus (Arun Kumar and Javahar, 2014). Diazinon is one of the most important organophosphorus pesticides. As a persistent pesticide, it is highly toxic to fish and aquatic invertebrates (Coupe et al., 2000; Samadi et al., 2019). This chemical is easily washed away after use, entering aquatic environments in significant quantities (Aydın & Köprücü, 2005). Many species of large branchiopods occur in temporary habitats surrounding agricultural areas and farmlands, which serve as locations where Phallocryptus spinosa can be found (Atashbar et al., 2014). Phallocryptus spinosa inhabits temporary freshwater to brackish water bodies, the hydroregime patterns of which are highly unpredictable. These habitats typically fill in early spring and dry out by summer (Atashbar et al., 2014). Environmental pollution from diazinon-one of the most widely used agricultural pesticides-affects the life cycle of zooplankton, such as fairy shrimp, and threatens their populations. Thus, understanding the impact of such substances on the environment, particularly aquatic ecosystems, is essential. Therefore, this study aimed to investigate the effects of diazinon insecticide toxicity on the growth, survival, and activity of antioxidant and digestive enzymes in P. spinosa larvae. Methodology This study was conducted at the Artemia and Aquaculture Research Institute of Urmia University. P. spinosa shrimp cyst hatching was performed following the method recommended by Atashbar et al. (2012). To determine the 24-hour LC50 of diazinon, a preliminary range-finding test was first conducted using 30 shrimp larvae (in triplicate) (Lan and Lin, 2005). Based on these results, three experimental treatments (Table 1) were selected to investigate the effects of sublethal diazinon concentrations on shrimp rearing conditions. Survival and growth rates were assessed on days 1, 3, 5, and 7 using the methods of Rahimi and Nejatkhah Manavi (2011) and Agh et al. (2008). The activities of SOD, CAT and GPX enzymes were measured according to Yazdanparast et al. (2008). Malondialdehyde (MDA) activity was determined based on thiobarbituric acid inhibition by MDA in the crude enzyme extract (Ledwożyw et al., 1986). Digestive enzyme activities were measured as follows: Alkaline protease: Garcia-Carreno and Haard (1993), Lipase: Iijima et al. (1998), Alpha-amylase: Bernfeld (1955). Data were analyzed using one-way ANOVA in SPSS (version 21), with a significance level (Type I error) set at α = 0.05. Results The comparison of mean survival percentages (Table 3) revealed a significant decrease due to diazinon exposure (p < 0.05 Day 3: a significant difference (p<0.05) was observed between treatment 1 (control) and treatment 4 (100% diazinon). Day 5: significant differences (p<0.05) were detected between treatment 1 and treatments 2 (25% diazinon), 3 (50% diazinon), and 4. Also, treatments 2 and 3 vs. treatment 4. Day 7: significant differences (p<0.05) occurred between treatment 1 and treatments 2, 3, and 4 and between the treatment 2 and treatments 3 and 4. The highest survival rate was recorded in treatment 1, while the lowest was in treatment 4 (100% diazinon) (p<0.05). Comparison of mean growth indices (Table 4) revealed a significant decrease due to diazinon exposure (p<0.05). The significant differences were observed as follows: day 3: treatment 1 (control) vs. treatments 3 (50% diazinon) and 4 (100% diazinon), day 5: treatment 1 vs. treatments 3 and 4; treatment 2 (25% diazinon) vs. treatment 4; day 7: treatment 1 vs. treatments 2, 3, and 4; treatment 2 vs. treatments 3 and 4; treatment 3 vs. treatment 4. The highest growth rate was observed in treatment 1 (control), while the lowest occurred in treatment 4 (100% diazinon) (p< 0.05). The results for whole-body antioxidant enzyme activity and malondialdehyde (MDA) levels (Figure 1) showed significant increases due to diazinon exposure (p<0.05). Significant differences were observed in: SOD activity: treatment 1 (control) vs. treatments 2 (25% diazinon), 3 (50% diazinon), and 4 (100% diazinon); CAT activity: treatment 1 vs. treatments 3 and 4; GPX activity: treatment 1 vs. treatments 2, 3, and 4; treatment 3 vs. treatments 2 and 4; MDA content: treatment 1 vs. treatments 2, 3, and 4; treatment 4 vs. treatments 2 and 3. The results of whole-body digestive enzyme activity (Figure 2) showed significant increases due to diazinon exposure (p<0.05). Alkaline protease, lipase, and α-amylase in treatment 1 (control) showed significant differences compared to treatments 2 (25% diazinon), 3 (50% diazinon), and 4 (100% diazinon) (p<0.05). The α-Amylase in treatment 4 differed significantly from treatments 2 and 3 (p<0.05). The lowest and highest levels of alkaline protease activity were observed in treatments 1 and 4, respectively, and the lowest and highest activity of lipase and alpha-amylase enzymes were observed in treatments 1 and 3, respectively (p<0.05). Discussion and conclusion The results of this study demonstrated that shrimp larval survival decreased with increasing diazinon concentration. This aligns with findings by Taylor et al. (1998), where pollutant exposure affected vital functions in zooplankton, leading to population density reduction, decreased oxygen consumption, and nutritional limitations that ultimately impact survival rates. Additionally, shrimp larval growth declined at higher diazinon concentrations. Asadpour et al. (2012) attributed such growth reduction to disturbances in feeding behavior and alterations in biochemical and physiological responses to pollutants. Toxins reduce growth through absorption and organ damage (Cong et al., 2009; Rudnicki et al., 2009; Aggarwal et al., 2013). Our results demonstrated elevated levels of SOD, CAT, GPX, and MDA following diazinon exposure. The increased SOD and CAT enzyme levels reflect stimulated free radical elimination (Rumley and Paterson, 1998), while elevated GPX activity indicates an enhanced antioxidant defense capacity against radical chain reactions in P. spinosa (Schneider et al., 2005). The rise in MDA content suggests diazinon-induced lipid peroxidation (Jafari et al., 2012). We also observed increased digestive enzyme activity at various diazinon concentrations. This may result from toxin-induced stress altering feeding behavior and subsequent digestive enzyme secretion (Suzer et al., 2006). In summary, diazinon exposure at different concentrations: (1) reduced survival and growth rates, (2) disrupted vital physiological functions in P. spinosa larvae. Conflict of interest The authors declare no conflict of interests. Acknowledgment We extend our heartfelt thanks to the Office of Vice Chancellor for Research and Artemia and Aquaculture Research Institute of Urmia University for enabling this research. 29 42 2025/02/112025/07/72025/02/20 1403/12/2 2025/08/12025/08/12025/08/1 1404/5/10 بهروز آتشبار کنگرلویی Behrooz Atashbar Kangarloei گروه اکولوژی و مدیریت ذخایر آبی، پژوهشکده آرتمیا و آبزی‌پروری، دانشگاه ارومیه، ارومیه، ایران Iran b.atashbar@urmia.ac.ir مجتبی پوراحد انزابی Mojtaba Pourahad Anzabi گروه شیلات و آبزیان، دانشکده منابع طبیعی، دانشگاه ارومیه، ارومیه ایران Iran adel.porahad@yahoo.com رامان امینی Raman Amini گروه شیلات و آبزیان، دانشکده منابع طبیعی، دانشگاه ارومیه، ارومیه ایران Iran ramanamini75@gmail.com Diazinon Growth Survival Antioxidant enzymes Digestive enzymes Phallocryptus spinosa دیازینون رشد زنده‌مانی آنزیم‌‌های آنتی‌‌اکسیدانی آنزیم‌های گوارشی Phallocryptus spinosa Aggarwal, V., Deng, X., Tuli, A. and Goh, K.S., 2013. 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مقاله علمی – پژوهشی:‌ ارزیابی ویژگی‌های اقتصادی-اجتماعی تعاونی‌های صید پره استان گلستان Evaluation of socio-economic characteristics of beach seine fishing cooperatives in Golestan Province 1 1 این پژوهش با هدف ارزیابی فرصت‌های شغلی، هزینه‌ها، دستمزد و حقوق افراد شاغل، سودآوری فعالیت و ویژگی‌های جمعیت‌شناسی تعاونی‌های صید پره استان گلستان برای سال بهره‌برداری 1400-1399 انجام شد. داده‌ها و اطلاعات تحقیق به روش پیمایشی و از طریق پرسشنامه از 10 تعاونی صید پره نمونه مستقر در ساحل شرقی (صیدگاه گمیشان) و ساحل غربی (صیدگاه میانکاله) جمع‌آوری شد. 16 تعاونی صید پره فعال، تعداد ۴۱۶ فرصت‌ شغلی ثابت را ثبت کردند که میانگین موقعیت شغلی به ازاء هر تعاونی10±26 نفر محاسبه شد. تعداد کل افراد شاغل تعاونی‌ها 587 نفر با میانگین (± انحراف معیار) 13±37 نفر به ازاء هر تعاونی به‌دست آمد. میانگین ساعات کاری سالانه پرسنل شاغل در کل ساحل و ساحل غربی به‌‌ترتیب 23 و 37 درصد بیشتر از استاندارد کشوری و در ساحل شرقی 16 درصدکمتر بوده است. هزینه‌های پرسنلی بیشترین سهم (۳/67 درصد) و هزینه‌های تعمیر و نگهداری دومین رتبه را در بین هزینه‌های متغیر نشان داد (۷/17 درصد). میانگین دستمزد ماهانه هر پرسنل شاغل در کل تعاونی‌ها 1155876±2526786 تومان برآورد شد که برای پرسنل شاغل در ساحل غربی (1291226±2709892 تومان) 29 درصد بیشتر از پرسنل ساحل شرقی (786939 ±2099540 تومان) بود. برای رسیدن به نقطه سر به سر درآمدها، مقدار صید هر تعاونی باید ۵۶ برابر مقدارصید موجود افزایش یابد. میانگین سنی افراد شاغل 3/7± 5/48 سال، میانگین تعداد خانوار هر پرسنل 42/0±۴ نفر و سهم ماهیگیری پره در معیشت و درآمد افراد شاغل ۴۲ درصد تعیین شد. شاخص‌‌های اقتصادی نشان داد که ماهیگیری پره در حال حاضر فاقد سوددهی بوده است و ادامه فعالیت توجیه اقتصادی ندارد. کاهش تعداد اعضاء فعال تعاونی‌های پره با هدف افزایش سهم دستمزد افراد شاغل و نوسازی تجهیزات صیادی به منظور کاهش هزینه‌‌های تعمیر و نگهداری برای افزایش عملکرد اقتصادی تعاونی‌ها پیشنهاد می شود. 2 Introduction Based on socio-economic studies, fishing is considered a complex activity worldwide, arising from the interrelation of different groups of fishermen, limited and valuable resources, and an increasing demand for supply in the consumer market (Pinello et al., 2017). The main objectives of socio-economic studies are to analyze the livelihoods of people directly involved in the fisheries, employment opportunities, profitability levels of the activity, and demographic patterns. Beach seine fishing, in the form of fishing cooperatives, is the only permitted fishing gear for bony fish in Iranian waters of the Caspian Sea during the six-month fishing season from mid-October to mid-April. Various studies have evaluated the social problems (Forouhesh Tehrani, 2013), economic conditions (Dad et al., 2013; Yazdani et al., 2017) of bony fish from beach seine fishing cooperatives. The beach seine fishery plays a crucial role in the livelihoods and income of local fishermen, and it also serves as a significant source of protein for coastal communities. However, there is a lack of comprehensive information on the socio-economic performance of the fishery. This study aimed to evaluate various socio-economic indicators of existing beach seine cooperatives in the Golestan province during the 2020-2021 fishing season, including employment, costs, remuneration, profitability, livelihood, and demographics. Methodology The socio-economic variables were collected through a sampling survey and by completing a questionnaire from the beach seine fishing cooperatives located on the West (Miankaleh) and East (Gomishan) coasts of Golestan province. The survey period spanned one calendar year, coinciding with the fishing season from October 6, 2020, to April 14, 2021. A stratified random sampling strategy based on ecological characteristics was designed (Pinello et al., 2017). Given that the total number of active beach seine fishing cooperatives was less than 50 (13 on the west coast and 3 on the east coast), 50% of the cooperatives were selected for sampling, i.e., 7 cooperatives from the West coast and all 3 cooperatives from the East coast. The questionnaires consisted of 76 separate variables, and the data were analyzed in 4 indicator groups: social, economic, socio-economic indicators, and demographic characteristics (Pinello et al., 2017). Indicators were derived from the questionnaire variables to evaluate the socio-economic status of beach seine cooperatives. Results The 16 beach seine fishing cooperatives provided a total of 416 employment opportunities, and the contribution of the West coast was 73.6% (306 jobs) and the East coast 26.4% (110 jobs). The average (±SD) working hours per engaged crew based on national full-time equivalent were calculated as 1.23 ± 0.3 for the entire coastline and 1.37 ± 0.4 and 0.84 ± 0.1 for the west and east coasts, respectively. The variable costs along the coast were estimated at 14.4 billion Tomans in Iranian currency, of which personnel costs accounted for 67.3% (9.7 billion Tomans) and repair and maintenance costs, 17.7 % (2.54 billion Tomans). The average monthly remuneration per crew member engaged along the entire coastline was estimated at 2,526,786±1,155,876 Tomans, and on the West and East coasts at 2,709,892±1,291,226 and 2,099,540±786,939, respectively. The economic profit for all the fishing cooperatives and cooperatives on the west and east coasts was negative. The average break-even revenues per cooperative for the entire and the West coast were calculated as 50.8 ± 2.3 and 2.8 ± 1.4 billion Tomans, respectively, but a negative number for the East coast. The catch to achieve the average break-even revenues would be 1,376,186 ± 81,934 kilograms per cooperative for the entire coast and 82,573 ± 56,589 kilograms for the Eest coast. The average age of the crew member was 48.5±7.3 years, and the average number of households per crew was 4±0.42. The share of beach seine fishing activities in the household income was 42 %.  Discussion and conclusion The beach seine fishing cooperatives on the West coast create employment opportunities 2.8 times greater than the East coast. The national full-time equivalent working hours indicated that the crew engaged along the entire coast and the west coast work 23% and 37% higher than the national reference level, respectively, and 16% lower on the East coast. Personnel costs, i.e., remuneration, account for the largest share (67.3 %), and repair and maintenance costs ranked second (17.7 %) among the five variable cost indicators, which are consistent with the previous findings for the cooperatives along the Caspian Sea (Salehi et al., 2016). The negative economic profit of the cooperatives reveals that this fishing activity is not profitable. To reach the break-even revenues, the catch amount of each beach seine cooperative must increase 56 times greater than the current catch, that is, it must increase from the current 24.6 ±11.3 tons to 1,376.1±81.9 tons per cooperative. The members of the fishing cooperatives are mainly middle-aged people with an average age of 48.5±7.3 years, which is very similar to the average age of fishermen for Kilka fisheries in the Caspian Sea (47.7 years) (Taghavimotlagh et al., 2020). Reducing the number of active members of the beach seine cooperatives and renovating the fishing equipment is proposed to increase the economic performance of the cooperatives. Conflict of Interest The authors declare that there are no conflicts of interest. Acknowledgment We want to express our gratitude to the Iranian Fisheries Research Sciences Institute for their cooperation and financial support. This study is part of project No. 3-77-1230-043-000628. 43 53 2025/02/112025/07/72025/02/202025/04/22 1404/2/2 2025/08/12025/08/12025/08/12025/08/1 1404/5/10 سیدعباس حسینی Abbas Hosseini موسسه تحقیقات علوم شیلاتی کشور Iran ab_hossaini@yahoo.com نور محمد آبیار N. Abyar مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان گلستان Iran abyarnm@yahoo.com سیدامین الله تقوی مطلق S.A. Taghavimotlagh مؤسسه تحقیقات علوم شیلاتی کشور Iran s_taghavimotlagh@hotmail.com غلامرضا دریانبرد G.R. Daryanabard موسسه تحقیقات علوم شیلاتی کشور Iran daryanabard@gmail.com محمد لاریجانی M. Larijani موسسه تحقیقات علوم شیلاتی کشور Iran mohamadlarijani@gmail.com محسن یحیایی M. Yahyaei اداره کل شیلات استان گلستان Iran mohsenyahyaei45@gmail.com رضا شیرازی R. Shirazi اداره کل شیلات استان گلستان Iran shirazi1351@gmail.com Beach seine cooperative Bony fish Golestan province remuneration livelihood تعاونی پره ماهیان استخوانی استان گلستان دستمزد معیشت Dad, S., Ghorbani, R., Darijani, A., Yulghi, S. and Yahyaee, M., 2013. A survey of profitability and performance of fish beach seine Cooperative Companies in Golestan Province, 2009-2010. Journal of Utilization and Cultivation of Aquatics. Vol. 2(1), 27-40. (in Persian) ##FAO, 2005. Supporting small-scale fisheries through an enabling environment. Committee on Fisheries, Rome, Italy, 7-11 March 2005, COFI/2005/5.##Forouhesh Tehrani, G., 2012. Social Problems of Seine Fishermen and Affecting Factors. Journal of Village and Development. 15(4), 155-178 (in Persian)##General Directorate of Cooperatives, Labor and Social Welfare, 2020a. https://kordestan.mcls.gov.ir/icm_content/media/image/2020/04/386984_orig.pdf (in Persian) ##General Directorate of Cooperatives, Labor and Social Welfare, 2020b. https://kordestan.mcls.gov.ir/icm_content/media/image/2020/04/386172_orig.pdf (in Persian) ##International Labor Organization. 1996. ##https://www.ilo.org/dyn/normlex/en/f?p=NORMLEXPUB:12100:0::NO::P12100_ILO_CODE:C180##Robles, R. ed., 1999. Review of Mediterranean Fisheries Situation and Management, Informes y estudios COPEMED, n. 1.##Onlus, I., 2006. Evaluation of the capital value, investments, and capital costs in the fisheries sector. No FISH/2005/03. 203 p. ##Pinello, D., Gee, J. and Dimech, M., 2017. Handbook for fisheries socio-economic sample survey–principles and practice. FAO Fisheries and Aquaculture Technical Paper No. 613. Rome, FAO. 118 pp.##Salehi, H., 2016., The current economic status of Fisheries (Fishery and Aquaculture) in Guilan, Mazandaran, and Golestan provinces. Iranian Fisheries Science Research Institute, Tehran. 168 P. (In Persian)##Salarpouri, A., 2022. A study on the effects of the COVID-19 pandemic on fisheries activities in the Caspian Sea, Persian Gulf, and Oman Sea. Iranian Fisheries Science Research Institute, Tehran. 91 P. (In Persian)##Statistical Yearbook of Iranian Fisheries Organization, 2024, Planning and Development Office of the Iranian Fisheries Organization, 64 p. (In Persian)##Taghavimotlagh, S. A., Daryanabard, G.R. and Gee, J., 2020. Socio-economic analysis of kilka fisheries in the southern waters of the Caspian Sea (Iranian waters). Iranian Journal of Fisheries Sciences. 20 (2), 430-448. DOI: 10.22092/ijfs.2021.350934.0.##Taghavimotlagh, S.A., Daryanabard, G.R., and Vahabnejad, A., 2021. Socio-economic analysis of shrimp fishing vessels in Bushehr province and determining the role of this fishery in creating employment and income in 2018. Journal of Fisheries Science and Technology, 10(2):105-117. (In Persian)##Yazdani, S., Riahi, A. and Peykani, G., 2017. The Economic Analysis of Pareh-Cooperatives in the Mazandaran Province. Iranian Journal of Agricultural Economics and Development Research. 48(2), 211-226. (in Persian).## ##

مقاله علمی – پژوهشی:‌ تأثیر افزودن تائورین به جیره حاوی پودر چربی بر شاخص‌های خونی، ایمنی، آنزیم‌‌های آنتی‌اکسیدانی و کبدی قزل‌آلای رنگین‌کمان (Oncorhynchus mykiss) Effects of taurine supplementation in diet containing fat powder on hematological, immunological parameters antioxidant and hepatic enzymes in rainbow trout (Oncorhynchus mykiss) 1 1 در مطالعه حاضر، تأثیر اسید آمینه تائورین بر شاخص‌های خونی، ایمنی، آنزیم‌های آنتی‌اکسیدانی و کبدی در ماهی قزل‌آلای رنگین‌کمان (Oncorhynchus mykiss) تغذیه شده با جیره حاوی پودر چربی مورد بررسی قرار گرفت. جیره‌های آزمایشی شامل کنترل مثبت (حاوی روغن ماهی و روغن کانولا)، کنترل منفی (پودر چربی و بدون تائورین) و جیره‌های مبتنی بر پودر چربی حاوی 5/0، 1 و 2 درصد تائورین بودند. 225 عدد قزل‌‌آلای رنگین‌‌کمان با میانگین وزنی اولیه 03/0±00/12 گرم، به مدت 58 روز، روزانه سه بار در حد سیری با جیره‌های آزمایشی تغذیه شدند. نتایج نشان داد، اختلاف معنی‌‌‌داری در هموگلوبین بین تیمارهای مختلف آزمایشی مشاهده نگردید (05/0<p) درحالی‌که گلبول سفید و قرمز با افزودن 2 درصد تائورین بیشترین مقدار را نشان داد (05/0p<). هماتوکریت و متوسط حجم گلبول قرمز در جیره تائورین 1 درصد و اما متوسط هموگلوبین در گلبول قرمز در جیره کنترل منفی و متوسط غلظت هموگلوبین در گلبول قرمز در جیره تائورین 5/0 درصد در بالاترین سطح قرار داشت (05/0>p). علاوه‌براین، افزودن تائورین 2 درصد به جیره منجر به افزایش غلظت کلسترول، تری‌گلیسرید، پروتئین تام و گلوکز گردید. مقادیر آسپارتات آمینوترانسفراز و آلانین آمینوترنسفراز با افزودن 2 درصد تائورین به جیره حاوی پودر چربی به طور معنی‌داری کاهش یافت (05/0>p). همچنین فعالیت آنزیم‌های کاتالاز و سوپر اکسید دیسموتاز در تیمار حاوی 2 درصد تائورین و فعالیت آنزیم گلوتاتیون پراکسیداز در تیمارهای 1 و 2 درصد تائورین ارتقاء یافت و بالاترین فعالیت مالون ‌دی‌آلدهید مربوط به جیره کنترل منفی بود (05/0p<). به‌علاوه، با افزودن 2 درصد تائورین فراسنجه‌های ایمنی (ایمنوگلوبین، کمپلمان و لیزوزیم) بهبود یافتند. بر اساس یافته‌های مطالعه حاضر، افزودن تائورین 2 درصد به منظور بهبود شاخص‌‌های خونی، بیوشیمیایی، فعالیت آنتی‌‌اکسیدانی و ایمنی در قزل‌‌آلای رنگین‌‌کمان تغذیه‌‌شده با جیره مبتنی بر 70 درصد پودر چربی پیشنهاد می‌گردد. 2 Introduction Rainbow trout (Oncorhynchus mykiss) is one of the most important cultured species because of its high adaptability to various environmental conditions, rapid growth in intensive farming systems, and habituation to commercial aquafeeds (Parchami et al., 2022). Fish oil had been a main raw ingredient in aquafeeds for a long time; however, its availability has become increasingly limited (Gasco et al., 2018). In Iran, fat powder, a by-product of oil extraction, has potential for mass production. Nevertheless, the incorporation of fat powder into fish diets may adversely affect fish health due to the presence of saturated fatty acids, low digestibility, and associated side effects (Keramat  Amirkolaie et al., 2014; Adhami and Keramat Amirkolaie, 2016). The complete or partial replacement of fish oil with these saturated oils can negatively impact lipid lipolysis and immune function (Abedian Kenari et al., 2010; Adhami and Keramat Amirkolaie, 2016). Furthermore, diets high in unsaturated fatty acids are associated with increased lipid peroxidation in mitochondria, leading to liver cell damage (Abedian Kenari et al., 2011). Taurine plays a crucial role in fish physiology, including bile acid conjugation, immune regulation, osmoregulation, antioxidant effects, and the development and regeneration of the nervous system (Salze and Davis, 2015; Xu et al., 2020). It also regulates liver oxidative status (Martins et al., 2019), aids in detoxification, and stimulates immune responses in bony fish (Cheng et al., 2018; Dehghani et al., 2020). Recognized as a potent antioxidant, taurine mitigates oxidative stress by acting as a non-specific scavenger of harmful reactive oxygen species, thus protecting cells from oxidative damage and enhancing the synthesis of antioxidant enzymes (Hosseini et al., 2017). This research aims to evaluate the potential of taurine as a valuable additive in aquaculture feed. The current study is designed to assess the effects of taurine on blood indices, immune system function, antioxidant enzyme activity, and liver function in rainbow trout (O. mykiss) fed with a diet containing fat powder. Methodology A total of 225 rainbow trout with an average initial weight of 12.00±0.03 g was randomly assigned to 15 tanks, each containing 150 liters of water for 58 days. Five experimental diets were formulated: a fish oil and canola oil-based diet (positive control), fat powder-based diet (approximately 70% of the fat source was derived from fat powder) supplemented with 0% (negative control), 0.5%, 1%, and 2% taurine. The fish were fed three times daily at 8:00, 12:00, and 18:00 until apparent satiation. At the end of the trial, blood samples were taken from the caudal fin of each fish. The samples were allowed to clot and were subsequently centrifuged at 4600 rpm for 10 minutes to obtain serum. Hematological parameters, including red blood cell (RBC) and white blood cell (WBC) counts, hemoglobin concentration, and hematocrit levels, were measured. Additionally, serum biochemical parameters including cholesterol, triglycerides, total protein, glucose, albumin were determined. Hepatic enzyme (aspartate aminotransferase (AST) and alanine aminotransferase (ALT)), antioxidant indices (superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and malondialdehyde (MDA)), and immune indices (complement, lysozyme and immunoglobulin) were also assessed to evaluate the health status of fish fed diet containing taurine and fat powder. Results According to the results, the fish fed with 2% taurine indicated the highest levels of WBC and RBC (p<0.05). The highest values of hematocrit and MCV were obtained in fish fed 1% taurine (P<0.05). MCH and MCHC amounts elevated in the negative control group and at the 0.5% taurine dietary level, respectively (p<0.05). In contrast, the concentrations of hemoglobin were not significantly affected by the experimental diets (p>0.05). The serum biochemical parameters showed that the inclusion of 2% taurine led to the highest levels of cholesterol, triglycerides, total protein, and glucose; However, the albumin content remained unaffected (p>0.05). The concentration of triglyceride reduced with the addition of 0.5% taurine to the diet, while the lowest levels of cholesterol and glucose were found in the negative control group (p<0.05). The highest concentration of total protein was observed with the supplementation of 2% taurine (p<0.05). Furthermore, the activities of AST and ALT in negative control were significantly higher than those of fish fed 2% taurine (p<0.05). Antioxidant indices demonstrated significant differences in SOD, GPx, CAT, and MDA among the experimental groups (P<0.05). The highest levels of SOD and GPx were obtained by inclusion of 1.5% and 2% taurine, while the lowest amounts were observed in the negative control (p<0.05). Immunological parameter indicated that the addition of 2% taurine to diet containing fat powder resulted in an improvement of immunoglobulin, ACH50 and Lysozyme compared to the negative control (p<0.05). Discussion and conclusion The results of the current study suggest that reduced damage to the blood cells of fish fed a diet supplemented with 2% taurine may lead to an increase in hematocrit, RBC and WBC counts. Previous research indicates that taurine deficiency can contribute to blood cell destruction (Takagi et al., 2006, 2011). Furthermore, taurine plays a crucial role in synthesizing bile acids from cholesterol, which may reduce the need for bile acids and promote greater cholesterol reabsorption. This implies a decrease in hepatic absorption for bile acid synthesis in fish fed with 2% taurine, consistent with findings in rosy barb fish (Pethia conchonius), which taurine significantly increased triglyceride and cholesterol levels (Nejatizadegan et al., 2020). Taurine also interacts synergistically with insulin and insulin-like substances to enhance glucose and amino acid uptake in fish cells (Michelato et al., 2018). Additionally, taurine actively participates in glucose metabolism (Bañuelos-Vargas et al., 2014). The reduction in ALT and AST levels indicates that there are no adverse effects when taurine added to diet containing fat powder, aligning with similar findings reported in common carp (Cyprinus carpio L.) (Liu et al., 2024). At the same time, the improvement in antioxidant capacity and reduction in fat oxidation demonstrate the protective effects of taurine. In Asian swamp eel (Monopterus albus), the addition of 0.2% taurine to oxidized fish oil was shown to increase antioxidant enzyme activities (SOD, GPx, CAT) while reducing MDA levels (Zhang et al., 2022). The enhancement of immune indices, including ACH50, Lysozyme, and immunoglobulin levels, underscores the importance of taurine in maintaining immune function. Conversely, taurine deficiency has been shown to disrupt immune function (Schuller-Levis et al., 1990). In conclusion, the addition of 2% taurine positively affects bile salt production, fat digestion, and overall fat metabolism. It mitigates the negative effects of fat powder on liver function while improving blood parameters, immune function, and antioxidant activity. Conflict of interest There is no conflict of interest between authors. Acknowledgment This research was carried out with the assistance of the members of the Fisheries Department at Sari Agricultural Sciences and Natural Resources University, who provided laboratory and workshop facilities for this experiment. We would also like to thank the esteemed management of the Livestock and Aquatic Feed Company for their sincere cooperation in providing the raw materials for the fish diet. Special thanks to the esteemed manager of Kimia Growth Industry for supplying the fat powder. 55 67 2025/02/112025/07/72025/02/202025/04/222025/03/18 1403/12/28 2025/08/12025/08/12025/08/12025/08/12025/08/1 1404/5/10 فاطمه نوروزی Fatemeh norouzi دانشگاه علوم کشاورزی و منابع طبیعی ساری Iran fatemenorouzi1999@gmail.com سکینه یگانه Sakineh Yeganeh دانشگاه علوم کشاورزی و منابع طبیعی ساری Iran s.yeganeh@sanru.ac.ir فرید فیروزبخش Farid firouzbakhsh دانشگاه علوم کشاورزی و منابع طبیعی ساری Iran f.firouzbakhsh@yahoo.com بتول ادهمی Batoul Adhami دانشگاه علوم کشاورزی و منابع طبیعی ساری Iran amine.adhami@yahoo.com Sustainable aquaculture amino acid substitution fish oil immune system آبزی‌‌پروری پایدار اسید ‌آمینه جایگزینی روغن ماهی سیستم ایمنی Abedian Kenari, A., Mozanzadeh, M.T. and Pourgholam, R., 2010. 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مقاله علمی – پژوهشی:‌ پایش میکروبی منابع آب سطحی در حوضه آبریز سرشاخه‌های رودخانه سیروان (سنندج) طی سال‌های 1403-1402 Microbial monitoring of surface water resources in the Sirvan River tributary catchment basin (Sanandaj) during 2023-2024 1 1 پایش میکروبی منابع آب سطحی به‌ویژه در نواحی حساس مانند حوضه‌های آبریز سدها، نقش حیاتی در حفظ سلامت عمومی و پایداری اکوسیستم‌های آبی ایفاء می‌کند. این مطالعه با هدف بررسی وضعیت آلودگی میکروبی در حوضه آبریز رودخانه سیروان در استان کردستان طی سال‌های آبی 1403-1402 انجام شد. نمونه‌برداری‌ها به ‌صورت ماهانه و با رعایت شرایط استریل از شش ایستگاه منتخب شامل ایستگاه 1 (بالادست قشلاق، زیر پل)، ایستگاه 2 (شاخه قشلاق رود قبل از تصفیه خانه)، ایستگاه 3 (شاخه قشلاق رود، پایین دست تصفیه خانه)، ایستگاه 4 (شاخه قشلاق رود، حدود 3 کیلومتر پایین‌تر از ایستگاه 2)، ایستگاه 5 (شاخه گاوه رود) و ایستگاه 6 (شاخه سیروان، پشت سد) انجام گرفت. شاخص‌های میکروبی شامل شمارش کل باکتری‌ها، کلیفرم‌های کل، کلیفرم‌های مدفوعی و  Escherichia coliبا استفاده از محیط‌های کشت پلیت کانت آگار و ECC کروم آگار مطابق با استاندارد APHA  (2017) اندازه‌گیری شدند. نتایج نشان داد که بار میکروبی در ایستگاه‌ها تفاوت معنی‌داری دارد (05/0p≤) به‌طوری‌که ایستگاه ۴، واقع در پایین‌دست تصفیه‌خانه، دارای بیشترین میزان آلودگی بود و در ماه آبان غلظت کلیفرم‌های کل تا ۷۰۰۰۰۰ واحد تشکیل‌دهنده کلنی در 100 میلی‌‌لیتر ثبت شد. در مقابل، ایستگاه ۵ واقع در منطقه‌ای با کمترین فعالیت انسانی، دارای کمترین بار میکروبی بود. تحلیل فصلی داده‌ها نیز بیانگر افزایش قابل‌ملاحظه شاخص‌های آلودگی در فصل تابستان به‌ویژه در ایستگاه‌های مجاور فعالیت‌های انسانی و کشاورزی بود. یافته‌های این تحقیق نشان‌دهنده نقش مؤثر فاضلاب‌های انسانی، رواناب‌های کشاورزی و ناکارآمدی سیستم‌های تصفیه در کاهش کیفیت بهداشتی منابع آب سطحی منطقه است. با توجه به اهمیت رودخانه سیروان در تأمین آب شرب و کشاورزی استان کردستان، نتایج این مطالعه می‌تواند مبنایی برای شناسایی نقاط بحرانی، اصلاح زیرساخت‌های تصفیه و تدوین برنامه‌های پایش و مدیریت مستمر کیفیت آب سطحی در سطح حوضه آبریز باشد. 2 Introduction The Sirvan River is a vital freshwater source in Kurdistan Province, flowing through both urban and rural landscapes. Its proximity to human settlements, agricultural zones, and livestock operations increases the risk of contamination from untreated wastewater and surface runoff. Consequently, microbial monitoring of surface water within this watershed is essential for evaluating the region’s sanitary and environmental conditions. Microorganisms in aquatic ecosystems, beyond their ecological functions, are widely recognized as reliable indicators of water quality. Fluctuations in microbial populations often signal the presence of pollutants such as domestic sewage, animal waste, and nutrient compounds (Bradshaw et al., 2016). Among these indicators, coliform bacteria particularly fecal coliforms and Escherichia coli are of critical importance due to their intestinal origin and thermotolerance, making them precise markers of contamination from human and animal sources (Aenab and Singh, 2015). Numerous international studies have explored the factors influencing the presence and distribution of indicator bacteria in surface waters. For example, Pall et al. (2013) and Islam et al. (2017) examined the roles of temperature, precipitation, land use, and wastewater treatment efficiency in microbial load variation. Newton and McMahon (2011) investigated the relationship between organic and inorganic compounds and microbial community structure in lakes. At the watershed scale, Flood et al. (2022) highlighted the influence of geological and hydrological features on microbial contamination in rivers. Similarly, Park et al. (2021) demonstrated the impact of vegetation cover and land slope on bacterial distribution in South Korea. In Iran, several studies have addressed microbial water quality. Roshani-Sefidkouhi et al. (2025) assessed the Chahnimeh reservoirs in Sistan and Baluchestan Province, while Khatib Haghighi and Ghaani (2018) evaluated urban and rural drinking water sources in Gilan Province using total and fecal coliform indicators. However, most of these investigations were limited to cross-sectional designs or specific seasons. Comprehensive studies on spatial and seasonal variations of microbial indicators in Iranian rivers particularly the Sirvan River remain scarce. This study presents a year-long monitoring of microbial indicators, including total coliforms, fecal coliforms, and E. coli, across six stations in the Sirvan River watershed, covering a full hydrological cycle (July 2023 to June 2024). By analyzing seasonal and spatial trends and examining the influence of surrounding human activities, this research offers a novel approach to surface water quality assessment. The findings aim to identify pollution hotspots, evaluate sanitary conditions, and inform water quality management strategies for Kurdistan Province and similar regions. Results Microbial contamination in the Sirvan River watershed was assessed by quantifying total bacteria, total coliforms, fecal coliforms, and E. coli across multiple stations and seasons during 2023–2024. Maximum recorded values were 1×10⁸ CFU/100 ml for total bacteria, 7×10⁵ for total coliforms, 4.2×10⁵ for fecal coliforms, and 3.7×10⁵ for E. coli. The highest total bacterial count occurred at Station 2 in November 2023, while peak coliform and E. coli levels were observed at Station 4 in January 2024. Seasonal analysis revealed that bacterial concentrations peaked in summer (6.56 ± 0.32 log CFU/100 ml) and were lowest in winter (5.55 ± 0.87 log CFU/100 ml). Spatially, Station 3 consistently exhibited the highest bacterial load, while Station 2 had the lowest. Statistically significant differences were found between winter and other seasons (p≤0.05), as well as among stations (p≤0.05). Total coliforms followed a similar seasonal pattern, with highest mean counts in summer (4.87±0.77 log CFU/100 ml), followed by autumn (4.27±0.95), spring (3.86±0.50), and winter (3.12±1.91). Stations 3 and 4 were the most contaminated, while Stations 1 and 5 consistently showed the lowest levels. Seasonal variation in total coliforms was statistically significant (p≤0.05), with summer values markedly higher than winter. Fecal coliforms also peaked in summer (3.23±1.72 log CFU/100 ml) and were lowest in winter (2.72±1.72). Station 4 recorded the highest levels, significantly differing from other stations (p≤0.05), while Stations 1 and 5 had the lowest. However, seasonal differences in fecal coliforms were not statistically significant. E. coli concentrations were highest in summer (3.09±1.58 log CFU/100 ml) and lowest in winter (2.97±1.51). Stations 3 and 4 again showed the highest contamination, with statistically significant differences compared to other stations (p≤0.05). Stations 1 and 5 did not show significant contamination levels. Seasonal variation in E. coli density was not statistically significant. Overall, the data revealed pronounced spatial heterogeneity in microbial contamination, with consistently elevated levels at Stations 3 and 4 areas characterized by intensive human and agricultural activity. Seasonal effects, particularly during summer and autumn, were major contributors to increased bacterial loads due to higher temperatures and runoff. These findings underscore the need for targeted pollution control measures in identified hotspots within the Sirvan River catchment. Discussion and conclusion  The elevated bacterial concentrations observed in downstream stations (2, 3, and 4) of the Sirvan River reflect the impact of human activities, including the discharge of untreated or partially treated sewage and agricultural runoff (Helmer and Hespanhol, 1997; Agarwal and Rajwar, 2010; Aenab and Singh, 2015). These conditions are exacerbated by warm water temperatures, reduced flow rates, increased evaporation, and higher pollutant loads factors consistent with microbial contamination patterns in similar ecosystems (Rusiñol et al., 2020; Rather et al., 2023; Al-Afify et al., 2023). The presence of E. coli in elevated concentrations is a clear indicator of fecal contamination and poses serious health risks to communities near the river. The findings highlight the inadequacy of existing wastewater treatment systems and the urgent need for infrastructure upgrades to mitigate pollution. Lower bacterial concentrations at upstream sites suggest the effectiveness of natural filtration by vegetation, topographical separation from pollution sources, and hydrological buffering (Yaghoubzadeh and Safari, 2016; Wang et al., 2022). This study reinforces the importance of regular microbial water quality monitoring in the Sirvan River watershed using robust indicators such as E. coli. Effective management requires prioritizing the identification and control of both point and non-point source pollution, especially during peak contamination seasons. Strategies should include improved wastewater treatment, public awareness campaigns, and ecological restoration of water bodies. Integrated watershed management, supported by collaboration among water, health, and environmental authorities, is essential for safeguarding water quality and public health. Conflict of interest The authors declare that they have no conflict of interest Acknowledgment We hereby sincerely thank the Caspian Sea Ecology Research Center and Iranian Fisheries Science Research Institute for providing the scientific and laboratory basis for this research. 69 81 2025/02/112025/07/72025/02/202025/04/222025/03/182025/07/26 1404/5/4 2025/08/12025/08/12025/08/12025/08/12025/08/12025/08/1 1404/5/10 زهرا یعقوب زاده zahra yaghoubzadeh پژوهشکده اکولوژی دریای خزر، مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، ساری، ایران Iran za_yaghoub@yahoo.com فائزه ترک پهنابی Faezeh Turk Pahnabi پژوهشکده اکولوژی دریای خزر، مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، ساری، ایران Iran pahnabifaezeh@gmail.com Microbial monitoring fecal coliform Escherichia coli Sirvan River water quality پایش میکروبی کلیفرم مدفوعی Escherichia coli رودخانه سیروان کیفیت آب Aenab, A.M. and Singh, S.K., 2015. 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