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Spiny lobster species are ecologically important and highly prized as seafood globally. Populations of spiny lobsters have been impacted by overfishing, the harvesting of juveniles for seeding aquaculture, the spread of virulent disease, and declines in recruitment and natural habitat. Many spiny lobster populations cover vast geographic ranges, maintained via ocean-going larval dispersal, which makes effective management challenging. Determining the genetic structure and phylogeographic boundaries are important in fisheries and aquaculture for defining appropriate units for management or breeding. Nevertheless, the common patterns of biogeographic distribution and connectivity of spiny lobster populations are generally not well understood. This review summarizes recent genetic advances in our understanding of these patterns and presents several meta-analyses to help discern the common processes driving them. Due to the probable link between biogeographic patterns among species and phylogeographic patterns within species, the spatial patterns of recent genetic stock divergence were investigated with the assistance of a new comprehensive and time-calibrated phylogeny for palinurids. Meta-analyses of biogeographic and phylogeographic patterns were used to identify common patterns of genetic stock divergence. A model is proposed that synthesizes the current understanding of the common processes of divergence of palinurid genetic lineages, emphasizing the importance of allopatry, ecological adaptation, and changing patterns of connectivity over time. Overall, the results highlight the importance of major biogeographic boundaries in structuring spiny lobster stocks over a broad scale, while oceanographic features and stochasticity dominate at smaller scales. These insights will assist the management of spiny lobster fisheries and aquaculture development, by better identifying and understanding the genetic units expected to be most appropriate for management and breeding, even in those species that have not yet received intensive genetic study. [ABSTRACT FROM AUTHOR]

The effects of dietary aflatoxin B1 (AFB1) and zearalenone (ZEA) co-contamination on goldfish, Carassius auratus, was investigated. Total of 540 C. auratus fingerlings with an average body weight of 6.25±0.12g were randomly distributed in nine different experimental groups with 3 replicates comprised of three dietary levels of AFB1 (0, 50 and 100ppb) and ZEA (0, 500 and 1000ppb). Fish were fed with the experimental diets for 60 days. Then growth and nutritional indicate and pathology of gill and intestinal tissue were investigated. The results showed that dietary AFB1 and/or ZEA contamination depressed the growth performance, and nutritional indices of the experimental groups; the highest and lowest WG, final body weight, TGC and DGC were belonged to control group and AFB50ZEA1000, respectively (P<0.05). Although the nutritional indices, including PER, PPV and LER, were not significantly different among the experimental groups (P>0.05), the fish fed the diet containing 500 ppb ZEA had the lowest value of LPV (P<0.05). The highest intestine tissue inflammation (4.0±0.75) and necrosis (4.0±0.75) scores were observed in AFB100ZEA500 group (P>0.05). Also, the simultaneous presence of AFB1 and ZEA in the diet increased the severity of the gill tissue damage, including hyperplasia, congestion, hemorrhage, and lamellar fusion in almost all treatments containing AFB1 and ZEA (P<0.05). The results revealed that dietary co-contamination of AFB1 and ZEA could negatively affect fish performance at concentration even lower than those indicated in the literature implying that the safe feed mycotoxin thresholds would be revised in terms of fish welfare and performance. [ABSTRACT FROM AUTHOR]

Many ecologically important and valuable fisheries marine species have been misidentified in terms of both the statistical data and market demand. Correct identification at the species level and the population genetic structure of the orange-spotted grouper (Epinephelus coioides), a precious fish in the Persian Gulf and the Oman Sea, was tested using mitochondrial cytochrome oxidase subunit I (DNA barcoding) and D-loop sequencing. The results revealed that the Epinephelus species found in the region, including E. coioides, E. bleekeri, E. polylepis, and E. chlorostigma were all mistakenly grouped together and identified as only E. coioides. Moreover, the analysis of molecular variance (AMOVA) of E. coioides samples using the D-loop showed a significantly unique genetic structure (ΦST = 0.068, p < 0.001) within the E. coioides population throughout the Persian Gulf and the Oman Sea, with the pairwise genetic difference between sampling locations in UAE and the Iranian coast. Moreover, D-loop sequences analysis showed two distinct haplotype groups scattered among the sampling locations, which did not correlate with the geographic distance between the sampling locations. These findings indicate that the issue of misidentification should be highlighted in the management and conservation of E. coioides. As this type of misidentification is likely to happen to other threatened marine species as well, the efficacy of using genetic markers for the correct identification, both at the species and the population level, is vital. [ABSTRACT FROM AUTHOR]

The objectives of this study were to investigate the effects of Oliveria decumbens as a medicinal herb with reported immunostimulatory potential on the growth, immunity status and health of Nile tilapia (Oreochromis niloticus). In an eight-week trial, fish (45 ± 5 g) were randomly divided into 13 treatments as follows: in 10 treatments fish were fed on diets containing 0 (control), 0.01, 0.1 and 1% of O. decumbens extract and essential oil and their 1:1 combinations. Also, in three treatments fish received plant hydrolate at doses of 312.5, 625 and 1250 ppm as bath treatment. At the end of experiment, blood samples were taken for immunological and biochemical measurements. All treated fish showed comparable growth performance to those received control diet. The highest levels of respiratory burst activity were observed in extract 1% group. Similarly the serum lysozyme levels were significantly affected by essential oil and extract supplemented diets. Fish received plant hydrolate at dose 312.5 ppm showed the highest significant protein level. Also, the globulin levels were increased in group fed on diet containing extract 1%. Plant supplementation had no negative effects on the fish health biochemical indices including cholesterol, triglyceride, alkaline phosphatase and aminotransferase enzymes. In conclusion, the results of this study showed that application of O. decumbens derivatives improved the immunity of Nile tilapia without adverse effects on fish growth and health. [ABSTRACT FROM AUTHOR]

A six‐week feeding trial was conducted to determine the effect of butyric acid (BA) inclusion in diet on performance of Barramundi (Lates calcarifer). Fish (12.0 ± 0.2 g) were fed with four experimental diets contained 0.0 (control), 2.5, 5.0 and 10.0 g BA/kg in triplicate. Fish fed on 5 and 10 g BA/kg diets had higher growth and total alkaline protease and lipase activities than the other treatments. Fillet protein content in BA‐supplemented groups was higher than the control. Liver catalase activity was highest in 2.5 g BA/kg group compared with the other groups. The values of liver superoxide dismutase activity and serum total protein concentration in 5 and 10 g BA/kg treatments were higher than those in the control (p <.05). Moreover, the highest and the lowest levels of serum lysozyme activity were noticed in the 10 g BA/kg and the control groups, respectively (p <.05). Also, the highest respiratory burst activity was observed in fish fed 5 g BA/kg feed. Supplementing diet with 2.5 or 5 g BA/kg resulted in higher serum haemolytic activity in fish compared with the other groups. The number of red and white blood cells increased in fish fed BA‐supplemented diets compared with the control (p <.05). In conclusion, the results of this study showed inclusion of BA at 5 g/kg diet in L. calcarifer juveniles improved growth and upgraded the general health condition by enhancing fish antioxidant enzyme activities and haemato‐immunological responses. [ABSTRACT FROM AUTHOR]

An 8- week feeding trial was conducted to investigate the effects of Ducrosia anethifolia essential oil on growth, blood immune parameters and immune related genes expression in juvenile rainbow trout ( Oncorhynchus mykiss ). Fish were allocated into 4 groups and fed on diet containing different levels of essential oil (0, 0.001, 0.01 and 0.1%) to apparent satiation in 30 min 3 times daily. Growth and immunological parameters were measured every ten days and tissue samples were taken from kidney and spleen on days 10, 30 and 50 to study the expression of IL-1β and TNF-α. The changes of measured parameters in different treatments and over sampling time series were statistically analysis based on repeated measurement method ( P < 0.05). Results showed that growth did not affected by essential oil at different treatments. The highest level of hematocrit was observed in 0.001 treatment. The mean of RBC showed no significant differences among treatments. The mean of WBC in 0.01 and 0.1 groups were higher than those in 0.001 and control groups. Total protein, albumin and globulin and serum bactericidal activity showed no significant difference in different treatments. Neither treatments nor sampling times affected serum lysozyme activity. The highest mean of respiratory burst activity was observed in 0.01 group. The highest expression of both IL-1β and TNF-α genes in kidney was observed at 0.001 dose on day 30, while in spleen, the highest expression of IL-1β and TNF-α was obtained on day 30 at doses 0.1 and 0.01%, respectively. In conclusion the results of this study showed that feeding with lower and medium level of D. anethifolia for 30 days led to immunostimulatory effects in juvenile rainbow trout. [ABSTRACT FROM AUTHOR]

The patterns of expression of two subunits of 20β-hydroxysteroid dehydrogenase (20β-HSD), key enzyme involved in the biosynthesis and activation of steroid hormones, were examined in rainbow trout by using a combination of quantitative real-time PCR and in-situ hybridization. The expression of targeted genes was examined in mRNA extracted from different tissues at different gonadal stages in male and female trout. Both subunits of 20β-HSD were found to be widely distributed in tissues. The highest expression of 20β-HSD A was found in intestine followed by skin, stomach, liver and gills, whereas, the highest expression of 20β-HSD B was observed in stomach followed by head kidney, ovary − at late vitellogenesis stage- and trunk kidney. In ovarian tissue 20β-HSD A was highly expressed in mature oocytes, and the highest expression of 20β-HSD B was in ovary at late vitellogenesis stage. There were no differences in the level of expression of either subunit among groups of rainbow trout at different stages of maturational competence. In male fish, 20β-HSD A was highly expressed in testis stage I in contrast to 20β-HSD B which was highly expressed in testis stage VIII. In situ- hybridization results showed that the 20β-HSD gene was highly expressed in gastrointestinal organs, while only slightly expressed in the gonadal tissue of fish at stage 62 day-post-fertilization (dpf). Overall, the results confirm the ubiquitous presence of 20β-HSD among tissues in rainbow trout with relatively minor fluctuations in expression associated with reproductive cycles which collectively suggests a wider metabolic role of these enzymes than just an association with the synthesis of control hormones for reproduction. [ABSTRACT FROM AUTHOR]

Wild carp ( Cyprinus carpio carpio ) forms the basis of an important fishery in the Southern Caspian Sea Basin which is increasingly underpinned by the release of cultured juveniles. A significant bottleneck to hatchery-rearing of juveniles is the spermiation of male broodstock. Therefore, four approaches to improving spermiation were investigated. The effectiveness of two delivery methods for the sustained release of salmon gonadotropin releasing hormone analogue (sGnRHa; i.e., via intramuscular cholesterol pellet vs emulsion injection) on the spermiation success and duration, sperm quality and quantity over 14 days in wild-caught carp were compared to single injection of sGnRHa with Pimozide ® (Linpe method) or carp pituitary extract (CPE). The consequence of the spermiation treatments on resulting embryonic quality was evaluated for subsequent fertilization and hatching success from wild male carp (mean weight ± S.D. 1021 ± 112 g). All hormonal treatments, except for Linpe method, led to 100% spermiation of treated fish compared to only 25% in the control with no hormone intervention. The duration of spermiation, as well as the various quantitative variables of the sperm and the mean total sperm production were all generally improved with the sustained hormone delivery compared with the acute treatments. The GnRHa-FIA was the most effective method for improving spermiation. [ABSTRACT FROM AUTHOR]

In this investigation, the effect of polyethylene film covered with essential oils of thyme and savory in order to control the lipid oxidation of rainbow trout fillet during short-term refrigerated storage was studied. Sensory and lipid quality indices were assessed in 3 day intervals and compared with control samples. The hydrolytic corruption was limited using essential oils in the packaging films. The higher values of conjugated diene in control samples showed further development of lipid deterioration. After covering the film with essential oils of thyme and savory, increasing the primary products of lipid oxidation was inhibited, respectively, until days 12 and 15. The secondary lipid oxidation product rate was limited after using essential oils in packaging films. Using essential oils, the taste and overall acceptance of the product were enhanced. During the storage period, the value of sensory evaluating indices was decreased in all samples while the change rate progressed much more in control samples. Practical Applications Covering of polyethylene film with essential oils of thyme ( T hymus daenensis Celak) and savory ( S atureja bachtiarica Bunge) for lipid oxidation control in rainbow trout ( O ncorhynchus mykiss) fillets during short-term storage in the refrigerator. [ABSTRACT FROM AUTHOR]

This investigation was conducted to survey the levels of some heavy metals such as cadmium, lead, chromium, nickel and cobalt in domestic cultivated and imported rice sold on the Shiraz – Iran markets. The potential human health risk assessment was conducted by considering estimated weekly intake (EWI) of toxic metals from eating rice and compared calculated values with provisional tolerable weekly intake (PTWI). The mean values for lead and cadmium in domestic cultivated and imported rice were considerably higher than allowable limits set by FAO/WHO. In combination of recent rice consumption data, the estimated weekly intakes of toxic element were calculated for Iranian population. EWI for cadmium, nickel, chromium through imported and domestic cultivated rice consumption was lower than the PTWI. The EWI for lead were considerably higher than other measured toxic metals. The highest mean level of EWI for lead was observed in some imported rice samples (25.76 μg/kg body weight). [ABSTRACT FROM AUTHOR]

Abstract: The effects of saline-dissolved or Freund''s incomplete adjuvant (FIA)-emulsified GnRHa treatment on the induction of ovulation in rainbow trout, Oncorhynchus mykiss, were examined. The FIA-emulsified GnRHa was first diluted in 0.25 ml physiological saline and then mixed with an equal volume of FIA. Fish were selected in the beginning of the spawning season and were allocated into four groups and were treated intraperitoneally with (a) 0.5 ml of emulsified GnRHa (GnRHa–FIA), (b) 0.5 ml saline-dissolved GnRHa in a single injection (GnRHa-1), (c) 0.5 ml saline-dissolved GnRHa in two injections spaced 1 d apart (GnRHa-2) and (d) 0.5 ml of saline (Control). The GnRHa dose in all hormone treatments was 25 µg kg−1. All fish in the FIA–GnRHa and GnRHa-2 groups ovulated within 10 and 11 d after treatment, respectively. In contrast, only 75% in the Control fish and 60% of the fish in the GnRHa-1 group ovulated within 36 d after treatment. None of the treatments caused any pre- or post-spawning mortality in the broodstock. Fertilization, eyeing and hatching percentages of the produced progeny were normal in all the treatment groups and did not differ significantly among them. In conclusion, FIA-emulsified GnRHa can be effective in advancing the onset of and synchronizing the ovulation of rainbow trout within a two-week period, thus shortening the egg collection period, without affecting broodstock survival and egg quality. [Copyright &y& Elsevier]