Using RAPD markers potential to identify heritability for growth in Fenneropenaeus indicus

Sampling was done using 90 post larvae which were produced by reproduction of some broodstocks of Fenneropenaeus indicus in one day and reared in the same situation for 4 months. Samples were divided into 3 groups: high, medium and low growth (based on weight and length). Genomic DNA was extracted from muscle tissue using the phenol-chloroform method. The polymerase chain reaction (PCR) was carried out using 21 RAPD loci and PCR products were separated on 3% Agarose gel. From 21 loci studied, 12 produced polymorphic bands. The most polymorphic produced bands using OPAQ 9 and the least by OPAQ 7. Search for specific markers in F. indicus one specific band was observed in the low growth group using OPAQ4. The highest genetic distance (0.457) was between the low growth group and the medium and the lowest (0.091) between high growth and medium groups, therefore the highest genetic identity (0.912) was between high growth and medium groups and the lowest (0.633) between low growth group and the medium. Neighbor-joining resulted in two groups, the first including high and medium growth groups and the second low growth group. It appears that low growth group depended on separated population. Considering the mean weight of F1 (mean weight of 90 specimens) (16.25±1.5 g), parental generation mean weight of 15 ±1.2 and mean weight of parent 31.6 g, response to selection (R) and heritability for growth in this species were estimated to be 1.2±0.2 and 0.07±0.01 respectively

Genetic variations of Iranian and French stocks of rainbow trout (Oncorhynchus mykiss)

Rainbow trout, Oncorhynchus mykiss is the most important cold water farmed fish as a nonindigenous species in Iran. Eyed eggs have been imported from different countries to Iran. In this study, genetic diversity of 50 fish (male and female) from Iranian generation and 24 fish from French generation were evaluated. Six microsatellite markers including OMM1019 ،OMM1036 ،OMM1307 ، OmyFGT5TU ،Omy77DU and Omy207UoG were applied. Average number of observed alleles in the Iranian and the French stocks were 6.68 and 6.83, respectively. Average number of effective alleles in the Iranian and French stocks were 3.13 and 3.45, respectively. Mean expected and observed heterozygosis was 0.68, 0.53 and 0.71, 0.61 in Iranian and French stocks, respectively. The results showed significant deviation from Hardy-Weinberg equilibrium at the most of loci × stock. Fixation index Fst calculated based on allelic frequency between two stocks was 0.058 with significant difference between 2 stocks. The results of this study showed insignificant genetic differentiation based on six microsatellite loci

Fluctuation of gonadosomatic index during oocyte development in the narrow-clawed crayfish Astacus leptodactylus (Eschscholtz, 1823) in Aras Dam Lake, Iran

This study was carried out with the aim of examining the seasonal reproductive cycle of the female crayfish Astacus leptodactylus from Aras Dam Lake, Western-Azerbaijan, Iran. Gonadosomatic index (GSI), and oocyte size were measured in females sampled seasonally in June, August, November (2011), January (2012). Development of the oocytes was categorized according to the diameter and the presence/absence of yolk granules. The ovary development was accompanied by increasing levels gonadosomatic index and egg diameter. Ovarian development histologicaly related to the seasonal GSI . This index was low in June (0.61±0.05) when oocytes started developing and reached the highest value in November (13.53±0.25), when vitellogenic oocytes were abundant in the mature ovary. Our results highlight the relationship between the ovary development and the GSI and egg diameter in the crayfish A. leptodactylus during the reproductive cycle and held important implications for the management of aquatic species. Thus, investigation of female A. leptodactylus reproduction is highly significant for fisheries managers as well as environmentalists concerned with perpetuating crayfish stocks

The study of nutrition and feeding position of shrimp, cultured in IRAN

The culture of Iranian Shrimps began in Bushehr in 1372. Early the green or the pink tiger shrimp (Penaeus semisulcatus) which were found in most habitats of the Persian Gulf and Oman Sea were considered in breeding and reproduction, but due to reproduction difficulties, it was rather replaced by the Monodun imported species, then the production of the white shrimp Metapenaeus affinis and Then P.merguensis in some southern areas of the country such as Hormozgan has began in small scale,but none of these species couldn't meet the economical needs of the consumer society and they were not indelible and dominant enough in the shrimp aquaculture industry of the country until breeding of Indian White Shrimp (Fenneropenaeus indicus) has began in large scale in the provinces of Khuzestan and Bushehr, which are seen as the heart of shrimps reproduction and breeding, and in Hormozgan and Sistan. the incidence of white spot viral syndrome (White Spot Syndrom Virus) led to the import of the western white leg shrimp from the USA (P.vannameii) by the Iranian Fisheries Research Organization (IFRO) in 1383, at the present all southern and northern breeding farms of the country (fundamental measures has been carried out in line of shrimp reproduction in Gorgan province in 1386) has put the breeding of this shrimp species as the single breeding species at top of their agenda. The subject of feeding the breeding shrimps is widespread and regarding to the non-proprietary species there are still some species which contain high protein than the other species in studying the different shrimp species requirements. In Iran due to the scarce factories producing the shrimp's food, the alimentary compound of the breeding shrimps during industrializing years of this type of breeding even after the non-aboriginal western white leg shrimp species being inclusive was stable and through different biological processes including: Naplies which feeds from its yalk and by entry into zoa stage start eating only small-sized phytoplankton. And by entry into the stage between zoa and mysis it feeds from phyto and zooplankton simultaneously and entering the post-larva stage it stars sarcophagi. and after 15 post-larva stage entering the growth and transition stage to earthen ponds feeding by concentrated industrial foods in large and small packages depending on young and adult mouth and due to feeding requirements of every stage the alimentary compound is nearly as follows: Digestible protein, energy, fat, carbohydrates, vitamins and minerals will start and the final product will be released in market Or they will be used in the later years of laying eggs and feeding for brood stock. In feeding section the details of every stage and their food's nutritional needs at each stage and will be fully described

Sonification as a Reliable Alternative to Conventional Visual Surgical Navigation

Despite the undeniable advantages of image-guided surgical assistance systems in terms of accuracy, such systems have not yet fully met surgeons' needs or expectations regarding usability, time efficiency, and their integration into the surgical workflow. On the other hand, perceptual studies have shown that presenting independent but causally correlated information via multimodal feedback involving different sensory modalities can improve task performance. This article investigates an alternative method for computer-assisted surgical navigation, introduces a novel sonification methodology for navigated pedicle screw placement, and discusses advanced solutions based on multisensory feedback. The proposed method comprises a novel sonification solution for alignment tasks in four degrees of freedom based on frequency modulation (FM) synthesis. We compared the resulting accuracy and execution time of the proposed sonification method with visual navigation, which is currently considered the state of the art. We conducted a phantom study in which 17 surgeons executed the pedicle screw placement task in the lumbar spine, guided by either the proposed sonification-based or the traditional visual navigation method. The results demonstrated that the proposed method is as accurate as the state of the art while decreasing the surgeon's need to focus on visual navigation displays instead of the natural focus on surgical tools and targeted anatomy during task execution

Nitrogen and phosphorous budgets for integrated culture of whiteleg shrimp Litopenaeus vannamei with red seaweed Gracilaria corticata in zero water exchange system

In this study, a 2×3 factorial design with two levels of shrimp density (25 and 50 shrimp per m2) and three levels of red algae density (0, 200 and 400g per m2) was applied to calculate nitrogen and phosphorous budgets in the integrated culture of Litopenaeus vannamei with Gracilaria corticata during 45 days in a zero water exchange system. Juveniles of L. vannamei (5.82±0.11 g) and G. corticata were cultured in 18 round 1 m3 poly ethylene tanks. Water temperature, dissolved oxygen (DO), pH and salinity were measured once every 3 days. Results indicated that shrimp density had a significant effect on pH and DO in the morning and in the afternoon. The algal density didn’t have a significant effect on pH and DO in culturing tanks (p> 0.05). According to the results of this study, the main source of nitrogen and phosphorus input to the tanks during a 45-day culturing period was from feeds. Shrimp and algal densities significantly affect the concentration of total ammonia, nitrite, nitrate and phosphate in water and an increase in shrimp density led to an increase of these compounds whereas, increasing the algal density led to the reduction of these compounds. Results indicated that increasing the density of G. corticata in all treatments, led to an increase in biomass of harvested shrimp and the co-culture of G. corticata with L. vannamei decreased the amount of nitrogen and phosphorus in both water and sediments and improved the water quality of L. vannamei culture

A survey of some biological aspects of cobia (Rachycentron canadum)

Biology aspects of cobia (Rachycentron canadum) were investigated from October 2005 to December 2006 in Northern waters of Persian Gulf (Hormozgan province).The reproduction cycle, sexual maturity, sex ratio, Fecundity, Lm50, feeding, length frequency, growth parameters and mortality of cobia were studied from total of 509 specimens ranged from 19 to 159 fork length. Gonadosomatic index peaked during spring and summer with main peak in June. Spontaneous spawning occurs around the year with peak in June. The overall female to male ratio was significantly 1 : 1.49 (P<0.05). Batch fecundity were estimated 1684954±118990 in 15 females. Relationship between total length and fecundity were calculated F=1.3717TL 2.9567 (r^2= 0.82). Feeding studies indicated that the bony fishes were main food of cobia (76%) and followed by crustaceans (25%) and mollusks (11%). Rays were least food items (22%). Maximum and Minimum GaSI were observed in March (33%) and August (0.07%) respectively. Females reached 50% sexual maturity at 81.25 cm TL. The total length -weight relationship was W=0.0042L3.1162 (r^2=0.9852). Thetotal length-fork length relationship was TL= 1.1561FL-2.533 (r^2= 0.9933). Growth parameters K, L, and t_0 were calculated by von bertalanfy growth equation: 0.11 (year1), 168.65 cm, 3.49 and -0.97 respectively. The instantons rate of total mortality (z), natural mortality (M) and fishing mortality estimated by catch curve analysis were 0.30, 0.25, 0.14 (year1). Exploitation rate and Tmax were 0.36 and 28 year respectively

Growth and survival rates, mean weight, food conversion ratio and total harvest in cultured Shrimp Litopenaeus vannamei in Iran

To introduce Litopenaeus vannamei to Iran as a cultured shrimp species, a experimental study was carried out to assess the effects of different stocking densities on growth rate, mean weight, survival rate, food conversion ratio and the total harvest of L. vannamei. Mee post-larval groups (P1,12) of L. vannamei (pond A: 20 PL/m2, pond B: 30 PL/m2 and pond C: 50 PL/m2) with average size 0.9cm and initial mean weight 0.01±0.005g were used in this study. The experiments were carried out in three replications in 9 earthen ponds each half a hectare in size in Khouzestan province, south of Iran during 110 days. The result showed there was no significant correlation (P>0.05) between stocking density and survival rate in the semi intensive culture condition. Mean survival rate among farms were greatest at the lowest density, where mean survival in pond A, B, and C was 88.6%, 83.3%, 73.3%, respectively but the differences were not significant (P>0.05). The results also showed there was no significant relationship (P>0.05) between growth rate and growth days in each experiment. The mean growth rate/days for ponds A, B, and C were calculated at 0.16g/day, 0.16g/day and 0.15g/day, respectively. The food conversion ratio in the end of the study period for ponds A, B and C was 1.01, 1.17 and 1.2, respectively. Shrimp production increased with an increase in stocking density when farm production at Pond A and B indicated a significant difference (P<0.05) compared to that of the pond C. The total shrimp production for ponds A, B and C was calculated at 2803kg/ha, 3146kg/ha and 3972kg/ha, respectively. The water temperature ranged between 28±3°C to 23±3°C, with the highest in July and lowest in September. Salinity ranged between 25±2ppt to 12±3ppt, pH ranged between 8.6±0.2 to 7.50.4 and dissolved oxygen ranged between 5.8± 0.4ppm to 5.3±0.3ppm throughout the study. The study proved that L. vannamei could adapt to common conditions in Iranian shrimp culture environment and also we showed that the species production was higher than the native species already under culture

Egg production and larval rearing of orange-spotted grouper (Epinephelus coioides) using reared broodstocks in Hormozgan Province, Iran

Egg production of cultivated broodstocks of orange-spotted grouper, Epinephelus coioides and larvae rearing were surveyed in Iran from 2008 to 2012. Broodstocks were obtained by rearing of 7 wild juveniles (587.57 ± 132.63 g body weight) which were caught from the north of Persian Gulf in October 2008 and reared to December 2012. Captured juvenile fishes were fed using defrosted trash fish at a rate of 4-6 percent of body weight per day. Four-year-old fishes spawned spontaneously, when average weight of females and males were about 7020 ± 1277 g and 5128 ± 253g respectively. Effects of four temperature ranges (23-24, 26-27, 28-29 and 31-32 °C) and three tank size ( 40L, 300L and 2400L) on hatching and survival rates were examined. Eggs were stocked as a density of 25 Eggs L^-1. Effects of tank size on hatching rate and survival of larvae were assessed at 1, 5, 10, 20 and 30 days after hatching (DAH). The optimal temperature range for hatching was 28-29°C. No difference was observed among hatching rates of fish within the various tank sizes. Survival rates of larvae in 2400L fiber glass tanks until 30 days after hatching were significantly higher than the other tanks. Results indicate this species can be reproduced and reared in large numbers under normal rearing conditions and carefully controlled temperature

Determination of optimum stocking density for whiteleg shrimp (Litopenaeus vannamei) culture in outdoor pond in Choeibdeh, Abadan

This study was carried out to investigate the optimum stocking density for white leg shrimp (Litopenaeus vannamei) in earthen ponds in Choweibdeh shrimp site Abadan southwest Iran. Six 0.5 ha. Earthen ponds were applied to survey three stocking density of this shrimp (30, 45 and 60 indviduals/m^2) with two replicates each. 15 days old postlarvae (PL15) with mean weight of 0.021 g were reared in the experimental ponds for 60 days. Results showed no significant difference (P>0.05 ) between the tested stocking densities in terms of growth (weight gain, length increment), specific growth rate (SG ), weekly growth rate, survival rate, food conversion ratio (FCR ) and protein efficiency rate (PER). Nevertheless best results were obtained in the stocking density with 30 ind./m^2 . Yield was increased by increasing the stocking density and the highest yield was obtained in the density of 60 ind./m^2 with significant difference with two other densities. Ultimately, according to the findings of the present study, stocking density of 60 ind./m^2 can be suggested as an acceptable density to be applied for white leg prawn in the region