JOURNAL OF APPLIED ICHTHYOLOGICAL RESEARCH
Year:2015 | Volume:3 | Issue:3|Papers Count:8

This study was carried out to identify the taxonomic composition of fish larvae collected bimonthly in waters of Bushehr to Genaveh in six stations (Five creeks: Shif, Lashkari, Ramleh, Farakeh, Dubbeh, and one station in the seashore) in norhtern Persian Gulf, Iran, from June 2013 to April 2014. Fish larvae were sampled usinga Bongo-net (diameter, 60 cm; mesh size, 300 mm). A total of 21440 fish larvae representing 30 families (which included two subfamilies, eightgenuses, nine species and eight types), one group to the levels of order and two types were recognised. The identified taxa were: Apogonidae, Blenniidae, Callionymidae, Carangidae, Clupeidae, Cynoglossidae, Diodontidae, Engraulidae, Gerreidae, Gobiidae, Haemulidae, Hemiramphidae, Leiognathidae, Mugilidae, Mullidae, Nemipteridae, Pegasidae, Platycephalidae, Scatophagidae, Sciaenidae, Scombridae, Sillaginidae, Soleidae, Sparidae, Sphyraenidae, Synanceidae, Syngnathidae, Terapontidae, Triacanthidae, Tripterygiidae, and Tetraodontiformes. Among them, Soledae (including 6 types) and Gobiidae (including 3 types) were the most diverse families. What is more, Pegasus volitans (Pegasidae), Cyclichthys orbicularis (Diodontidae), Trachurus indicus (Carangidae), and Hippichthys penicillus (Syngnathidae) were reported for the first time in Iranian waters.

The present study aimed at investigating the diet of white cheek shark, Carcharhinus. dussumieri, in order to determine its feeding preferences in Hormozgan waters, Persian Gulf. Overall, stomach contents of 360 shark were sampled including female (n=169) and male (n=191). The content of 360 white cheek sharks including 169 female and 191 male, which were caught using trawl and gill net during 18 months from December 2013 to May 2015, were examined. Diet of Whitecheek shark, with the length range of 41-98 and weight range of 500-5100 gr., was described using the numeric, frequency, weight methods and the index of relative importance index (IRI). Two hundred fifty two stomachs contained food items and small teleost fish were found in the majority of full stomachs. Results indicated that C. dussumieri fed on a wide variety of teleost species, primarily Engraulidae, Synodontidae, Nemipteridae with occasional crustacean and cephalopod prey. There was a significant difference in diets of males and females shark samples. The average prey content in the stomach was 1.59±0.84 and 1.51±0.81 for male and female, respectively. In addition, trophic level was calculated 4.4. A shift in diets of maturing, immature and mature males and females deemed to be an evidence that C. dussumieri experiences an ontogenetic feeding diet shift.

In this study 13 Chondrostoma regium specimens from the Leileh, Armand, Marbor, Shalamzar, and Koohrang Rivers in Zagros region were compared to other species of Chondrostoma and some species of the Leuciscinae subfamily. A total of nine 652 bp haplotypes were recovered. Results showed that C. regium in Karoon basin is a monophyletic group which is different from its counterpart in the Leileh River in Kermanshah Province. In addition, the highest genetic distance among the observed haplotypes was for Leileh-Armand and Leileh-Marbor Rivers (0.8%). The time elapsed since the isolation of C. nasus and C. kinzelbachi from C. regium and the isolation time between C. regium and C. lemmingii were calculated as about 2-3 MY and16 MY, respectively.

This study aimed at determining and identifying of salty waterfish diversity and abundance from 2011 until 2012. Three stations (station 1: Batvand, Station 2: KohZar, Station 3: DashtBozorg) were chosen and sampling was done using Gill net, Slick and Sachok. Results showed that 13 species of fish belonging to 5 families exist in this river. Cyprinidae with 9 species had the most frequency (80.9 %) and in other families one species were identified. The Capoeta trutta were the most dominant species in all stations and Capoeta trutta, Cyprinum macrostomum, Liza abu, Cyprinon kais with 41.7, 19, 16.7, 8.4 were the most frequent species, respectively. The most frequentspeciesin the stations one to threewas estimated to be Capoeta trutta with 47.2%, 40% and 32.3 %, respectively and the least frequent speciesin all the three stations was Apanius mento. The average water salinity was variable. Station 2 (KohZar) and station 3 (DashtBozorg) were observed to have the highest and the lowest salinity with 7.18 ppt and 1.91 ppt salinity indices, respectively. Also station 2 (KohZar) and station 3 (DashtBozorg) with 25.35 0C and 21.750C, had the highest and the lowest temperature, respectively. In the present study the highest species diversity was in station 3 (DashtBozorg) with 1.93 and the lowest was in station 1 (Batvand) with 1.56 (p>0.05).

This study was conducted to investigate the effect of activating solutions containing different concentrations of calcium, magnesium and pH change in the Billard standard fertilization solution on sperm motility of brown trout. Sperm catching from the male fish was done after anesthetizing. Sperm samples were then mixed together and density (87.0±30.10 million per milliliter) and spermatocrit (23.0±0.58%) of the pooled sample were calculated. Experimental activating solutions were prepared by addition of bivalent ions of calcium and magnesium with a concentration of 1, 2, and 3 mmol L-1 in the Billard solutions. Three other experimental groups were prepared by making changes in the PH of Billrd solution (8, 8.3, and 9). Then, Sperm motility in each experimental solutions and standard solution Billard (control) were compared. The highest Sperm motility of brown trout was found in the solution containing 1 mM calcium ion with the 64.7±8.6 s, which did not show significant difference with the solution containing pH 8 (p>0.01).The minimum duration of sperm motility was also recorded in pH 9.5 fertilization solution with the time of 24.3±2.6 s compared to the other treatments (p<0.01). Also, no significant difference was found in duration of sperm motility between Billard standard solution (control treatment) with treatments containing 1 mM magnesium, 2 mM magnesium and pH 8.5 (p>0.01). Among bivalent ions the most motility of brown trout sperm was observed in the solution containing 1mM calcium. Therefore, the type and concentration of bivalent ions followed by the pH in activating solutions could put the sperm motility under control.

The present study aims at investigating the Histopathological effects of nickel and copper on the gill of Kutum Rutilus kutum. To perform this study, 120 pcs kutum were caught from Syjval fish reproduction center (Bndar-turkmen) with average length of 4.5±0.25 meters and average weight of 1±1.1 gram. After the compatibility of the sample with laboratory conditions, the experiment was conducted in 30 days at concentrations of (CuCl2 1.3 mg/L and NiCl2 3.9 mg/L) in the aquarium with the dimensions 65×30×40 cm. Heavy metal concentrations in water solution was renewed every 48 and the tissue samples were caught during three periods of 7, 15 and 30 days. Results indicate that with the increase of exposure time to copper, damage to gill tissue, such as hyper-emia and hemorrhage, fractures and connectivity of secondary lamella and secondary lamella shortening, blade gill, lamella of swollen multi-cellular were more severe. Regarding Ni, the increase in mucus secretion and hyperemia resulted in secondary lamella fusion and hypertrophy. In sum, The amount of damage gill tissue in different concentrations of Cu was more than Ni.

Nowadays the production of resistant larva with high survival and desirable growth is so important in aquaculture industry. Due to the fact that larvae’s digestion is not completed after the absorption of yolk sac, the alive food should be used in this step. In this investigation, the Iranian Acipenser percicus larva growth and survival in 3 treatments feeding on 3 alive foods, Caspian Sea Acartia, Artemia and Daphnia were studied and each treatment in 3 replicates were done during 14 days. Experimental larval feeding results showed significant difference in final weight indicators, survival rate, food conservation ratio, gain weight percentage, specific growth and daily growth (p<0.05). The final obtained results showed that the best growth indicators were gained in the treatment fed by Caspian Sea Acartia was and the treatments fed by Artemia and Daphnia were placed in further ratings.

Use of Canthaxanthin on growth and non-specific immune indices of Green Terror Aequidens rivulatus fish feeding over a period of 8 weeks were evaluated. Sixty fishes with the average weight of 0.388±0.0021 gr were put into nine oval-shaped ponds of 120 liters capacity and fed twice a day in a completely randomized system. This study include three treatments: 1) control treatment, 2) the feed including fish oil, and 3) feed including fish oil complemented with Canthaxanthin extracted from D. natronolimnaea bacteria. At the end of the study period, four pieces of fish from each treatment were caught and their fish immune serum factors of total immunoglobulin, lysozyme activity, and alternative complement activity were investigated. The final weight (2.78 gr), SGR (3.33%/day) and FCR (1.28) had an improved condition in treatment number 3 compared with the other ones (p<0.05). Also, in treatment 3, the total immunoglobulin (3.35±0.07 mg/ml), lysozyme activity (3.87±0.09 mg/ml) and alternative complement activity (1.8±0.09 U/ml) in the serum of DN fed fish showed significant higher levels compared to other treatments (p<0.05). The results of this study revealed that the Canthaxanthin extracted from bacteria D. natronolimnaea has a positive impact on growth indices and non-specific immune system in Green Terror and the Carotenoids can be used as feed complementary in breeding this species of ornamental fish.