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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]

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]

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]