Growth and reproduction of (Capoeta damascina Valenciennes 1842) from the Hanna wetland, Semirum

As part of ecological study of Hanna Wetland, Semirum, in Isfahan province, the age, growth, and reproductive characteristics of Capoeta damascina, a major species of the wetland were investigated. A total of 270 specimens were collected by cast net and gillnets of different mesh sizes (5-70mm) during fall and winter 2007, and spring and summer 2008. The ratio of males to females was 1.0: 2.2 (MT). Seven (1+ to n and six (1+ to 6+) year classes were recorded for females and males, respectively. In all class, females were always larger than males. Maximum fork length and weight of 44.2 cm and 1545g for females and 40.0cm and 1300g for males were recorded. The minimum, maximum, and average absolute fecundity were 2203, 36763, and 19121±9503, respectively. According to Gonadostomatic Index (GSI) values, spawning of C. damascina occurs from May to June. The Von Bertalanffy growth parameters fit to size-at-age data were: K=0.136, L∞=66.96cm, to .0.161 years for females and K=0.174, 1,0,=54.70cm, t, 0.37 for males. The weigh-length relationships were described as W=0.0143L3a^0.471 (r^2 = 0.9597) for females and W=0.009401695 (r^2 =7- 0.9768) for males. According to b values obtained, both sexes show a positive allometric growth. The growth performance index 9' was estimated at 7.071 and 6.092 for females and males respectively that indicated a faster growth rate for females

Effect of different diets on fecundity, development time and body size of freshwater copepod Eucyclops serrulatus

The effect of five different diets consisting of green algae Scenedesmus quadricauda, cereal plant meal (wheat+white+canola+barley), fish food meal, mixed manure powder (chicken manure+cattle manure), and baker's yeast (Saccharomyces cerevisiae) were investigated on fecundity rate, larval development time and body length in freshwater copepod Eucyclops serrulatus. A complete randomized design was employed using an individual gravid female in 50ml vials at 26ºC water temperature. The maximum fecundity was obtained in copepods fed on fish diet (18.6±1.08, eggs /female; mean±SD) followed in order by baker's yeast (17.3±3.19), cereal plant meal (13±2.45), Scenedesmus (9.3±0.41), and mixed manure powder (8.6±0.82). The larval developmental time of copepod E. serrulatus was significantly different in copepods fed on examined diets. The mean shortest naupliar time (8.3±0.81 days) and copepodit time (1.0±0.70 days) were observed in copepods fed on fish food meal with a significant difference compared to other examined treatments. In addition, length and width of naupliar, copepodit, and adult of copepod E. serrulatus increased when copepods fed on fish diet and baker's yeast

An investigation on fish parasites in Hanna Wetland, Semirom, Isfahan Province

As a part of a major ecological study of Hanna Wetland, Semirum Region, Isfahan Province, parasitic infestation of 3 native and one introduced fish species were investigated. A total of 120 fish specimens were collected by both cast net and a series of gillnets between fall and winter 2007, and spring and summer 2008. Some of the observed parasites are reported for the first time as new host records of: Trichodina perforata on gill and skin of Carassius auratus auratus and three species of leeches namely: Glossiphonia heteroclite, Thromyzon tessulatum and Hemiclepsis marginata on the skin and fin bases of Capoeta damascina. Moreover, 14 internal and external parasites including: one protozoan; Ichthyophthirius multifiliis and two myxosporeans; Myxobolus varicorhini, Myxobolus sp., three monogeneans; Dactylogyrus lenkoran, Dactylogyrus intermedius and Gyrodactylus sp., two immature digeneans; Diplostomum spathaceum, Tylodephys sp., two mature digeneans; Allocreadium isoporum and A. layman, one unknown cyst, one Acanthocephalan; Acanthocephalorhynchoides sp., one cestoda; Khawia armeniaca. The highest prevalence of Diplostomum spathaceum (100%) was observed in Aphanius isfahanensis and Alburnus sp. However, the lowest prevalence was related to A. layman in Capoeta damascina in winter (0%), and autumn and spring (11%). Leeches infections were only observed in Capoeta damascina and Alburnus sp. in winter and summer, respectively. The maximum average (±SD) infection intensity belonged to K. armeniaca in intestine of C. damascina in spring (12.50±3.40, range: 8-16). Among the parasites identified in the region, D. spathaceum showed the highest mean (±SD) abundance (41.67±11.79) in C. auratus auratus in spring. In general, a relatively high diversity of fish parasitic fauna exists in this water body which could jeopardize fish populations and the whole ecosystem if the ecological status of the Hanna Wetland is neglected

Short communication: optimization of semi-quantitative RT PCR analysis for CPT I gene expression in rainbow trout (Oncorhynchus mykiss)

A key enzyme in mitochondrial β¬oxidation, carnitine palmitoyltransferase (CPT) I, is transcriptionally regulated in mammals, but this enzyme also experiences allosteric modulations (Harano et al., 1985; Murthy and Pande, 1987; Bezaire et al., 2004). CPT I is located on the inner side of the outer mitochondrial membrane and catalyses the conversion of acyl-CoA to fatty acylcarnitine (Kerner and Hoppel, 2000; Price et al., 2000). Quantitative RT-PCR is a reliable technique for measuring transcripts in small amounts of tissue (Spriewald et al., 2000). With this technique, multiple mRNAs can be assayed simultaneously in a relatively short period of time. Here we describe the standard procedure, optimized in our laboratory, to assess CPT I levels with β¬actin as an internal control in rainbow trout, and all the necessary controls to ensure a quantitative analysis. RNA Extraction and Reverse Transcription Total cellular RNA was isolated from liver of rainbow trout using RNX reagent (Cinnagen-Iran). To obtain cDNA, 1 µg of total RNA was subjected to reverse transcription polymerase chain reaction (RT-PCR) with MuLV reverse transcriptase using the RevertAidTM M¬MuLV Reverse Transcriptase Kit (Fermentase Life Science, Germany) and random hexamer primer. Reaction conditions in the reverse transcription step are mostly dependent on the enzyme and the primers of choice. Whereas other protocols to require the use of specific primers, we prefer to reverse transcribe the total RNA population with random hexamers so that different PCR analyses could be performed on the same cDNA sample

Age and growth of the Mesopotamian barb, Capoeta damascina, in central Iran

Age and growth of Mesopotamian barb, Capoeta damascina, were studied in the Zayandehrud River, in central Iran, from March 2007 to April 2008. Among the 689 specimens studied, age groups in males ranged from 1+ to 9+ and that in females ranged from 1+ to 10+. The sex ratio (1 M: 1.6 F) was not significantly different from 1:1 ratio. Maximum fork length and weight was 39 cm and 1.115 g for males and 54.2 cm and 2.340 g for females. In all age classes, females were larger than males. The most frequent age groups were 3+ in males and 4+ in females. The highest value for condition factor was observed in June. The growth of C. damascina was described by von Bertalanffy growth curve as k=0.01, L_∞=56.2 cm, t_0=-0.63 for males and k = 0.05, L_∞=117.1 cm and t_0= -0.43 years for females. The length-weigh relationship was described as W=0.0169L^2.95 (r^2 =0.98) for males and as W=0.0155L2.99 (r^2 =0.99) for females, indicating an isometric growth pattern in both sexes. Growth performance index φ` was estimated as 5.73 for males and 6.53 for females, indicating a faster growth rate in females

The interactive effect of water-borne cadmium and environmental hypoxia on common carp (Cyprinus carpio) metabolism

Regarding to the tight association between aquatic hypoxia and heavy metal contaminations in one hand and the role of both parameters on fish respiration, metabolism of carp could be assessed under single and mutual exposures to hypoxia and cadmium. Following measuring LC50-96h of cadmium (43.679 mg/l) for this species, 80 common carp were exposed to 10 different treatments, including control, acute (43.68 mg/l), sub-lethal (21.84 mg/l) and chronic (4.37 mg/l) cadmium as well as hypoxia for immediately (20% of saturation), 24h (40%) and 7 days (60%), and joint exposure of each similar treatment. By using of respirometer technique, we measured oxygen consumption rate in different time spans to calculate each individual standard metabolic rate (SMR), maximum metabolic rate (MMR), aerobic scope (AS), factorial aerobic scope (FAS) and critical oxygen tension (PCrit). Obtained data show that acute and sub-lethal cadmium treatments led to significant (P<0.05) increases in all metabolic indices in comparison with control group whilst the MMR and AS have been reduced (P<0.05) following hypoxia treatments. Combined treatments of hypoxia and cadmium led to reduce SMR and PCrit in all treatments and MMR, AS and FAS only in acute and sub-lethal treatments. In overall, hypoxia can act as a limiting stressor in carp while cadmium can account as a loading stressor

Effect of dietary wood betony, Stachys lavandulifolia extract on growth performance, haematological and biochemical parameters of common carp, Cyprinus carpio

A 6 week study was conducted to assess the effects of wood betony (WB), Stachys lavandulifolia extract on growth performance, hematological and biochemical parameters of common carp, Cyprinus carpio. Different levels of the WB extract (0, 2, 4 and 8 % weight per weight, W/W, 0WB, 2WB, 4WB and 8WB) in the diet were used. The results showed that final weight and weight gain were significantly improved by WB (p0.05). There were no significant differences in hemoglobin, hematocrit, mean erythrocytes of hemoglobin, mean erythrocyte volume, mean hemoglobin erythrocyte concentration and white blood cell (WBC) counts (p>0.05), while, red blood cells (RBC) counts showed significant declining trend by increasing the level of the plant extract from control to 8WB (p<0.05). Significant elevation in the levels of total protein, albumin and globulin and albumin/globulin ratio by increasing WB concentration in the diet were observed (p<0.05). Diet enriched by WB could decrease serum level of triglycerides and cholesterol in comparison with the control (p<0.05). Based on the results of this study, it could be concluded that feeding common carp with WB can improve growth and some immunity characteristics as well as lipid metabolism

The sub-lethal effects of cadmium on some gill histopathology in the cultivated Sterlet (Acipenser ruthenus)

The sub-lethal effects of water-born Cadmium (Cd) on histopathological changes of gill tissues were investigated on Sterlet, Acipenser ruthenus. In this research, 60 fish (41.69 ± 0.95 g and 23.98 ± 0.14 cm) were randomly distributed in 4 experimental groups, each with 3 replicates. The fish were exposed to different concentrations of Cd for 21 days under semistatic experimental condition as: 0, 16, 32 and 64 µg/L Cd. At the end of the experiment, the gill tissues were fixed in Bouin's solution for histopathological studies. Qualitative and quantitative changes of the gill tissues were analyzed. Several qualitative changes including hyperplasia, hypertrophy of epithelial cells and epithelial edema as well as necrosis, rings and fusion of gill filaments and secondary lamellae were observed in all treated fish including control group. Quantitative analysis based on organ index (Iorg) showed significant increase in histopathological changes in the gill tissues coincided by elevation of Cd concentration in the water. However, there was no significant differences in the organ index between control and 16Cd group.The results of this study demonstrate severe histopathological changes in the gill tissues after exposing to sub-lethal concentration of water-born Cd under experimental condition. The results of this study might be used as a guildline for evaluation of histopahological changes being induced by heavy metals in natural or cultivated environment for sturgeon fish

Determination of CPUA and distribution pattern of families Haemulidae, Nemipteridae and Ariidae in the Oman Sea

This trawl survey was carried out during 2013 for the stock assessment of families Haemulids, Nemipterids and Ariids in the Oman Sea. Sampling was carried out at five different stratum and depths. The highest value of CPUA of Haemulidae was estimated for Pomadasys stridens in “B” stratum (885.78 kg nm^-2), for Pomadasys kaakan at depths of 10-20 m (330.35 kg nm^-2), and for Nemipteridae it was estimated for Nemipterus japonicus in “D” stratum (1042.31 kg nm^-2) at 30-50 m depths (1734.97 kg nm^-2), and for Ariidae, it was estimated for Netuma thalassina in the stratum B (752.64 kg nm^-2) at 20-30 m depths (428.33 kg nm^-2). The highest biomass for Haemulidae was estimated in stratum B (320.53 ton) at 50-100 m depths (282.98 tons), and for Nemipteridae in “D” stratum (559.72 tons) and at depths of 30-50 m (604.04 tons), and for Ariidae it was estimated in “B” stratum (272.35 tons) and at 50-100 m depths (255.12 ton). Based on the results obtained, the highest species diversity for Haemulids was in “A” stratum at depths less than 50 m, while for Nemipterids it was similar in the total study area and different depth layers. Highest species diversity for Ariids were found in “A” and “D” strata at depth layers of 10-20 m and 30-50 m, respectively. In light of the fact that fishing efforts decreased during these years, our results illustrate that CPUA and biomass have ascending trends which indicate the relative stability of the stocks of these families

Nutritional value of freshwater mesozooplankton assemblages from Hanna Dam Lake, Iran, during a one-year study

Nutritional value of freshwater mesozooplankton, fatty acid (FA) and amino acid (AA) compositions were determined in the middle of each season for a one-year period from May 2009 to February 2010 in Hanna Dam Lake, Isfahan, Iran. FA and AA composition significantly (P<0.05) varied in relation to the seasonal changes of water quality, phytoplankton and zooplankton community. The content of saturated fatty acids (SAFA), mono unsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) ranged from 22.4-29.0%, 30.9-40.4%, 11.8-20.9% of dry weight (DW), respectively. The major SAFA were 16:0 (13.7-17.0 % DW) and 18:0 (4.9-7.0 % DW), whereas contents of MUFA were mainly 18:1n-9 (13.8-16.2 % DW), 16:1n-7 (6.9-13.6% DW), and 18:1n-7 (5.7-10.6% DW). The major PUFA were 18:2n-6 (2.6-11.7 % DW), 18:3n-3 (2.4-3.1% DW), 20:5n-3 (3.9-4.8% DW), 22:6n-3 (0.73-0.99% DW), and 20:4n-6 (0.56-0.73% DW). As for the ratios of n-3:n-6, the values were 0.70:1, 2.54:1, 2.10:1, and 1.73:1 in spring, summer, autumn and winter respectively. The mean essential amino acid (EAA) and non-essential amino acid (NEAA) were 28.7 and 71.3 %; 31.0 and 69.0 %; 31.63 and 68.4 %; 34.5 and 67.0 % of total amino acid in spring, summer, autumn and winter, respectively. The amount of tyrosin, isolucine, lucine, arginine, cysteine, aspartic acid, glycine and proline were higher in mesozooplankton population at summer and autumn compared to winter and spring