Modifications in fat and fatty acid composition during prolonged storage of canned common kilka (CLUPEONELLA CULTRIVENTRIS) were studied. In this study common kilka was processed under traditional Mediterranean method and then stored for up to 3 years. Qualitative characteristics including total fat, fatty acids profile, free fatty acids, thiobarbituric acid, fluorescence compound of filling media and aquatic phase of lipid extract in fish (row canned and stored canned) were determined and compared with each other. Results showed that canning led to a decrease in total fat, although during 3 years storage, total fat did not change significantly. During the long term storage, amounts of free fatty acids, fluorescence and secondary lipid oxidation compounds were increased significantly. After canning, linoleic acid of tissues increased significantly as result of the interaction between tissue lipid and filling media. EPA and DHA of canned fish tissue decreased. Some of these fatty acids with other specific fatty acids were found in the sunflower oil that was used for coating. During prolonged storage, the n-3/n-6 ratio of tissue’s fatty acids decreased. At the same time, this ratio, in filling media, increased. Results of this investigation showed that, with increase of storage time, interaction between tissue fatty acids and filling media increases.

The objective of the present study was to determine chemical composition and fatty acid profile of common Kilka, CLUPEONELLA CULTRIVENTRIS caspia, in the Caspian Sea. The chemical analysis revealed that the protein and lipid content of common Kilka were 15.05 and 6.5% of the fresh weight, and total MUFA, PUFA and SFA were found to be 37.00, 32.89 and 29.03% respectively. Palmitic acid (16: 0) among total SFAs, oleic acid (18: 1n-9) among MUFAs, Docosahexanoid acid (DHA) (22: 6n-3) among n-3 PUFAs and linoleic acid (LA) (18: 2n-6) among n-6 PUFAs were the most abundant fatty acids. The obtained results revealed that common Kilka is a better source ofw-3 PUFAs than w-6. DHA and eicosapentaenoic acid (EPA) were the major components of w-3 PUFAs. Levels of DHA and EPA were 20.79% and 6.97% respectively. The PUFA/SFA ratio was 1.13 in common Kilka. This ratio was more than the recommended minimum value (0.45).The EPA/DHA ratio was 0.34 in common Kilka. The present study suggests that common Kilka is rich in essential unsaturated fatty acids of the w-3 family, especially DHA which may be considered nutritionally attractive for human.

Fifty common kilka (CLUPEONELLA CULTRIVENTRIS) specimens from Guilan Province and fifty others from Mazandaran Province, South Caspian Sea were collected to study genetic variation in the fish using Restricted Fragment Length Polymorphism (RFLP) of the mtDNA. DNA was extracted from fin tissue by phenol-chloroform method. The PCR products were digested using 13 restriction endo-nuclease enzymes. Five out of thirteen restriction enzymes were polymorphic resulting in nine different haplotypes. The haplotype divergence ranged from 0.0073 to 0.0369. The mean value of haplotype and nucleotide diversity among populations was 0.7339±0.0006 and 0.0098±0.0, respectively. The nucleotide divergence among populations was 0.01%. Statistically significant differences in haplotype frequencies among all samples were observed (P<0.01). Therefore, we conclude the populations are different genetically.

In this study, the biological indicators (length, weight, age) and the stock of the common kilka (CLUPEONELLA caspia) in the Iranian waters of the Caspian Sea were investigated in 2020 and 2021. The results showed that the amount of kilka caught was 20050 tons in 2020, reached 20138 tons in 2021, and presented fairly stable. The catch per unit effort (CPUE) was 2. 298 and 2. 321 tons per vessel per night, respectively. The average fork length (±,standard deviation) of common kilka (male and female) was 100. 9 ±,11. 1 mm, and the minimum and maximum were 62. 5 and 137. 5 mm, respectively. In the catch composition, age groups of 3 and 4 years dominated the catch, representing 78. 9% and 77. 9%, respectively. In the years 2020 and 2021, the total biomass was estimated to be 92653 and 78135. 3 tons, age 3 had the highest biomass (31615. 1 and 22672. 6 tons, respectively). The biomass of mature individuals were 44277. 6 and 41606. 5, respectively. The ratio of matures to the total biomass was 47. 8% and 53. 2%, respectively. The acceptable biological catch (ABC) of this species was estimated at 18, 000 tons with a precautionary approach. During the last decade, the average catch of this species was 22769 ±,1904 tons, which is more than the estimated ABC.

In this investigation, a number of canned Killka with oil and brine filling media were produced to survey the impact of filling media type on canned common Killka quality by traditional Mediterranean method. Qualitative characteristics including moisture, total lipid, free fatty acids, peroxide, tiobarbituric acid, fluorescence compound in aquatic phase of lipid extract obtained from fish and canned fish, and the fluorescence compound existed in filling media were determined. Results showed that hydrolytic rancidity product and the filling media fluorescence compound in brine canned was higher than the oil canned. The primary and secondary lipid oxidation indices (tiobarbituric acid and peroxide) had no ideal efficiency to evaluate the loss of quality due to the filling media type, while the fluorescence index had perfectly showed the quality loss. With regard to present interactions between fish tissue and filling media, it’s recommended determine the amount of filling media fluorescence compound as a good technique for quality assessment.

The Feeding habits of CLUPEONELLA CULTRIVENTRIS caspia Bordin, 1904 in Iranian waters were investigated by examining the stomach contents of 240 specimens collected in 2008. The mean of fork length, weight common kilka were 101. 8± 7. 2 mm, 10. 6± 2. 4 gr. Condition factor calculated 1. 9± 0. 12. The results of this study show that their diet consisted of different prey, Copepoda representing the most important prey group (FP=59. 6%) as a magor food items and Acartia tonsa the dominant prey species (100%). The others prey were Cirripedia (Cypris balanus) (FP=37. 7%) as a secondry food items and Cladocera (Podon polyphemoides) (FP=2. 7%) that as a accidentally fed. In summer, the fish fed on a wider density )504± 101 specimen per fish) of food items than in the others seaons. The lowest feeding activity was recorded in spring (112± 10 specimen per fish). The mean of RLG was 0. 39± 0. 8. The amount RLG<1, so common kilka is carnivore. Now, due to the dominance of species A. tonsa in the Caspian sea, especially in coastal areas, as a habitat suitable food is inevitable for Common Kilka.

In this study, the growth parameters of Common Kilka (CLUPEONELLA CULTRIVENTRIS) in the Caspian Sea were studied in one season and, three stations of Babolsar, Bandar Amirabad and Bandar Anzali. A total number of samples, 300 fish were randomly caught by conical nets in the study areas and analyzed. Overall, the average total length of the three stations 11. 65 ± 1. 17 cm and 9. 64 ± 2. 58 g total weight. The average total length at Babolsar, Bandar Amirabad, and Bandar Anzali stations were 11. 64 ± 0. 99, 12. 48 ± 0. 97 and 10. 81 ± 0. 91cm, respectively. The average weight at Babolsar, Bandar Amirabad, and Bandar Anzali stations was 10. 07 ± 2. 41, 11. 11 ± 2. 20 and 7. 73 ± 1. 84, respectively. The logarithmic relationship between length and weight of Babolsar, Bandar Amirabad, and Bandar Anzali stations, respectively, W= 2. 2642 TL-3. 2663, W=2. 31 TL-3. 4378 and W=2. 3331 TL-3. 5275. The amount of b in the Babolsar, Bandar Amirabad and Bandar Anzali zone, were 2. 26, 2. 31 and 2. 33, respectively. the growth pattern of fish in three stations is negative allometric(b<3). Factor conditions of common Kilka fish at Babolsar, Bandar Amirabad and Bandar Anzali stations were 3. 88, 3. 25 and 2. 98, respectively. It showed that Common Kilkai fish were better in weight in the Behshahr station. The results showed that the living status was more suitable for common Kilka fish at Bandar Amirabad station than Babolsar and Bandar Anzali stations in the sampled season.

This study evaluates the genetical structure of Caspian Sea Common Kilka (CLUPEONELLA CULTRIVENTRIS caspia) during winter and Spring of 2013 by sequencing method.30 samples were gathered from Mazandaran and Gilan fisheries ports and the fins samples lived in ethanol 96%. Then the genetical studies were done in biotechnology laboratory of Caspian Seas ecological research center. The DNA genomic samples of soft ports of the fish fin extracted by ammonium acetate method. The chain reaction of polymerase (PCR) was used by a pair of designed primer, on fish's DNA genomic. The abundant of Alles, the true number of Allelles, the observed and expected Heterozygosity, the genetic likeness and difference and the amount of Fs+caluculated by Tajmia and Nei test of genetic software (Bio Edit and Arlequin). Dendrogram of genetic difference drawn by Mega 4 genetic software. Based on drawn phylogenetic tree, the samples of Guilan were divided from Mazandarn samples. The dendrogram of these fish showed that the D-Loop gene indentified the genetic structure of Caspian Seas Common Kilka and separates Mazandaran and Guilan populations directly.

The efficiency of several quality evaluation indices was assessed to determine the effect of steam cooking on common Kilka quality. For this purpose, samples were cooked by saturated steam (102-103oC) in a retort with 1.02 atmospherics pressure for 15 minutes. Qualitative characteristics, including total lipid, free fatty acids, tiobarbituric acid contents and the profile of fatty acids in raw and cooked fish were determined and compared with fluorescence contents (aqueous and organic phases) of lipid extract obtained from those samples. Results indicated the fluorescence method as a good technique for degradation quality assessment of cooked product compared with other methods.

The changes in biological structure and growth of common kilka were investigation during 2008-2017 in the Iranian waters of the Caspian Sea. Kilka fishing ships discharged theirs catch in three parts: Babolsar, Amirabad and Anzali. The sample based on the length of 5 mm were classified. Fork length ranged from 52. 5 to 142. 5 mm and mean (± SD) 101. 9± 10. 5 and fish fork length 92. 5-112. 5 mm of the population have been dominant 81(%) (n= 49759). The slight fluctuations in the average length with values were between 100 and 105 mm. During this period, fish of +3 and +4 years old have been dominant with frequency of 80-70%. The stability length and weighted mean of generation growth rate was indicative of relative stability and the average age of common kilka stability, the stability of the population are descendants entered and confirmed. The results showed that in the year 2008 the frequency of young fish 1-2 years was 15. 2% of the catch, but gradually in the following years, the abundance of these fish in the hake decreased, so that in 2017, only 10% of the catches were allocated. Pressure on young fish stocks is an opportunity to rehabilitate stocks of this species.