Growth Of Common Carp Research Articles

Effects of the medicinal plant, Tamarindus indica, as a potential supplement, on growth, nutrient digestibility, body composition and hematological indices of Cyprinus carpio fingerlings

Tamarindus indica, a beneficial herb, has many health benefits but there is limited research on its use in fish nutrition industry. The current study investigated the effects of incorporating extracts of T. indica into the canola meal-based diets of Cyprinus carpio (common carp); following which, the growth, digestibility, carcass and hematological markers were assessed. A total of six diets were formulated with varying concentrations of T. indica extracts (TIE) viz, 0 %, 0.5 %, 1 %, 1.5 %, 2 % and 2.5 %. The fish (N = 270, 15 fish/tank with triplicates) in each tank were fed experimental diets for 70 days. The study demonstrated that TIE supplementation significantly improved the growth of common carp when compared to 0 % TIE level (control). The best results were observed at 1 % TIE level for the specific growth rate (1.68 ± 0.03 %), weight gain (15.00 ± 0.57 g), and feed conversion ratio (1.36 ± 0.05). Conversely, the 2.5 % TIE level gave the least improvement in terms of growth performance. Specifically for nutrient digestibility, the maximum values of crude protein (CP, 67.60 ± 0.83 %), crude fat (CF, 67.49 ± 0.45 %) and gross energy (GE, 70.90 ± 0.56 %) were recorded at 1 % TIE level. In addition, the best results of body composition (protein: 63.92 ± 0.06 %, ash: 18.60 ± 0.03 %, fat: 7.12 ± 0.02 % and moisture: 10.36 ± 0.04 %) and hematological indices, were measured in carps fed with 1 % supplementation level. In conclusion, the overall health of C. carpio fingerlings was improved with TIE supplementation in the diet containing 1 % TIE.

Effect of long-term temperature-controlled rearing on growth traits and sexual maturity of common carp (Cyprinus carpio)

Many economically important fish have a long sexual maturation cycle, with the first sexual maturation time exceeding four years, which poses a long-term challenge for the cultivation of excellent varieties of these fish. Gonadal development and reproductive timing of fish are closely related to changes in environmental temperature. This study used the common carp as an economic fish model and set up three aquaculture modes for a one-month old common carp population: constant temperature test group (CTTG), normal temperature control group (NTCG), and variable temperature control group (VTCG). A long-term (approximately 11 months), temperature-controlled aquaculture experiment was conducted. The results of growth traits and gonadal development tests showed that at 10 months, the body length and weight of the CTTG were significantly higher than those of the other two groups. At seven months, the gonadosomatic index (GSI) value of CTTG was also significantly higher than that of the other two groups; At 10 months, the serum estradiol (E2) concentration of CTTG was significantly higher than that of the other two groups, while the testosterone (T) levels of VTCG and CTTG were significantly higher than those of NTCG, and only the 11-ketotestosterone (11-KT) concentration of VTCG was significantly higher than that of the other two groups. Simultaneously, qPCR analysis of sex hormone regulatory genes revealed that the expression of Cyp19a1a in CTTG ovaries was significantly higher than that in NTCG and VTCG ovaries, whereas the expression of Cyp11b and Hsd11b2 in VTCG ovaries was significantly higher than that in NTCG and CTTG ovaries. At 12 months, artificial reproduction revealed that only fish from the CTTG (66.67%) successfully laid eggs and fertilized normally. The results indicate that long-term constant temperature cultivation at 28 °C starting from the juvenile stage is not only beneficial for the body growth of common carp, but also promotes their gonadal development. This may be due to the conversion of T into E2 by Cyp19a1a in the common carp, ultimately facilitating the functional development of gonadal tissue under hypothalamus-pituitary-gonadal (HPG) axis regulation, normal egg laying, and fertilization. This study reduced the normal first sexual maturation time of common carp by at least 50% and provides a reference for the rapid cultivation of excellent varieties of other economically important fishes.

Effects of Different Stocking Densities on the Growth, Antioxidant Status, and Intestinal Bacterial Communities of Carp in the Rice–Fish Co-Culture System

Common carp (Cyprinus carpio) is a freshwater fish commonly farmed in rice fields, yet there were few studies on the intestinal functions and microbial community structure of common carp in the rice–carp co-culture system. Therefore, this study aimed to explore the effects of different stocking densities on the growth, antioxidant status, and intestinal bacterial composition of common carp in this system. This study was divided into three different stocking densities, including low density (LD, 10 fish, 52.9 g/m2), medium density (MD, 20 fish, 105.8 g/m2), and high density (HD, 30 fish, 158.7 g/m2), with a culturing period of 60 days. The results indicated that HD treatment inhibited the growth of common carp, as evidenced by the reduced final weight, WG, and SGR. In serum, the TG content in the HD group and the Cor content in the MD group were significantly increased. Meanwhile, HD treatment induced oxidative stress, manifesting specifically as increased SOD and CAT activities in the intestine or serum while reducing Gpx, GSH, and T-AOC in the serum. The 16S rDNA analysis indicated that the Simpson and Shannon indices of intestinal microbiota in the HD group were significantly higher than those in the LD group. At the phylum level, Proteobacteria, Cyanobacteria, and Firmicutes were dominant microbial communities in two groups. In addition, there was a significant difference between the two groups in the abundances of Actinobacterota and Bifidobacterium. Based on growth performances, biochemical indicators, and microbial diversity in rice–carp co-culture, low density (52.9 g/m2) may be more suitable in the rice–carp co-culture systems. In summary, this study contributes to a better understanding of common carp response to different stocking densities in the rice–carp co-culture system.

Evaluation of Himalayan nettle (Urtica ardens) extract meal in common carp (Cyprinus carpio) feed: Impact on growth performance, digestive enzyme activity and antioxidant capacity

This research aims to evaluate the impact of an extract derived from the leaves of Himalayan nettle (Urtica ardens) leaf extract on common carp, Cyprinus carpio, growth, digestive enzymes, fish body carcass composition, antioxidant system, and water quality parameters. For a duration of 90 days, experimental diets containing nettle extract were given to 150 fish (12.38 ± 0.53 g) in 15 tanks (10 fish per tank). The five groups in triplicate were: control or T0 (untreated), T1 (fed 0.3% extract), T2 (0.6% extract), T3 (0.9% extract), and T4 (1.2% extract). Results revealed that nettle extract in the diet increases common carp growth up to 0.9% concentration of extract. Its feed conversion ratio decreases, while weight gain and specific growth rate rise significantly compared to the control diet. No mortality was observed during the 90-day experiment. Dietary nettle extract did not affect whole-body fibre and crude ash percentages (p > 0.05). Nettle-fed and control groups showed significant differences in crude protein, body fat, and total body moisture (p < 0.05). After a 90-day feeding trial, 0.9% nettle extract-fed fish had higher protease, amylase, lipase, and cellulase levels than the control group (p < 0.05). When nettle content reached 1.2%, enzyme activity decreased. Orthophosphate production peaked at 4 and 8 hours after feeding, while ammonia excretion peaked at 2 and 6 hours. The control group excreted the most ammonia and orthophosphate, while the 0.9% group excreted the least. Liver and kidney SOD levels were higher in common carp fed a 0.6% nettle extract diet. Feeding with a 0.9% nettle extract diet improved hepatic lipid peroxidation, gut and liver glutathione. Gut and kidney SOD, catalase, LPO, and GSH increased dramatically on the 1.2% diet. Statistically, the 0.9% nettle extract (T3) group showed the overall best results compared to the control diet. These findings demonstrate the potential of nettle extract as a dietary supplement in aquaculture.

The effect of a genetically improved common carp stock on the productivity of pond ecosystem: Implication for selective breeding in nature-close conditions

Aquaculture in Central Europe is mainly performed in man-made fishponds. Common carp (Cyprinus carpio), the main fish species, grows on natural food developing in fishponds and supplemental feeds (SF). Previously, it was found that common carp (CC) growth may be improved by selective breeding (SB). However, there is a question if such stocks could utilize the fishpond natural resources better and increase the mass yield per unit of water surface area. Otherwise, SB would be useless. In this study, we compared the production parameters of two mirror CC stocks (M2 and M2 x AMC) fed with two supplemental feeds (grain and carp plant-based pellets). The cross-bred M2 x AMC represented a model stock with higher performance potential comparable to a stock after several generations of SB for better growth. The study was performed in fishponds of Fish Farm Klatovy under their common practice over the three age categories of carp (CO – C3). Each mirror carp stock was reared separately with an internal scaly control group (CG) to evaluate potential environmental biases. Performance and production parameters between the two mirror carp groups and distributed SF were compared from a total of 43 fishponds using generalized linear models. It was found that the M2 x AMC showed remarkably higher overall mean individual weight gain (by 24.9%; 281 g vs. 351 g) and survival (by 16%; 46.6% vs. 54.4%). Moreover, fishponds stocked with the M2 x AMC displayed significantly higher (23.7 – 58.3%) mirror and total carp mass and mirror, total, standardized, relative and estimated carp mass yields, while the CG performed similarly in both groups of fishponds. No effects of the SFs on the production parameters were observed. Results suggest that SB for faster growth in common carp for a minimum of 3–5 generations should be manifested in a gradual increase of mass yields without changing the fishpond management.

The Effect of Probiotic-Induced Fermentation of Restaurant Waste on the Growth of Common Carp (Cyprinus carpio) Fry

The study explores using the fermentation process to convert organic restaurant waste into fish feed, a promising solution for aquaculture. The aim is to determine the best type and dosage of probiotics for fermenting restaurant waste (FRWM) and evaluate their impact on common carp (Cyprinus carpio) fry growth. Three commercial probiotics (P1, P2, and P3) were used at an 8% concentration for fermenting the waste. The best result from the fermentation trial was tested as feed containing different FRWM proportions: 0% (TA), 10% (TB), 20% (TC), 30% (TD), and 40% (TE) with 30% protein content. The trial lasted 42 days, assessing waste chemical composition before and after fermentation, growth rate, amylase and protease activity, feed conversion, survival rate, and water quality. Results showed P1 was most effective, increasing FRWM protein content by 84.25% and reducing crude fiber and fat by 15.17% and 3.94%, respectively. TE (40% FRWM) yielded the best outcomes, with fry common carp achieving a 1.05% daily growth rate and a feed conversion ratio of 0.80, indicating efficient feed utilization. TC (20% FRWM) exhibited the highest survival rate at 88.33%. The inclusion of FRWM influenced amylase activity, increasing enzyme levels and improving feed efficiency and growth rate. In conclusion, using FRWM, fermented with P1 probiotics, showed significant improvements in its composition, leading to enhanced fish growth and feed utilization. The 40% FRWM diet demonstrated the best fish growth rate and feed conversion performance. These findings support using fermented restaurant waste as sustainable and nutritious fish feed in aquaculture.

The effect of banana peel flour (Musa paradisiaca) as additional feed raw materials for common carp (Cyprinus carpio)

Banana peel flour has a high nutritional content and can be used as a raw material for fish feed. The study was to find out the effect of banana peel flour as a raw material for feed on enhancing common carp fish growth. The study was conducted from February to April 2023 at the Fish Hatchery and Breeding Laboratory, Faculty of Marine and Fisheries, Universitas Syiah Kuala. The experimental group used a CRD with 5 treatments and 3 replications. The treatments included T0 (0%), T1 (2.5%), T2 (5%), T3 (7.5%), and T4 (10%) doses of additional Kepok banana peel flour. The sample fish used were an average weight of 1.64 ± 0.24 g fish.-1, which was cultured for 40 days. The parameters observed included survival, growth rate, and feed conversion ratio. The results revealed that adding Kepok banana peel flour as a raw material for common carp feed had a significant influence on absolute weight growth, specific growth rate, and feed conversion ratio (P&lt;0.05), but had no effect on survival (P&gt;0,5). The optimal percentage obtained was the addition of 7.5% banana peel flour in the feed formulation (T3) which was able to produce 1.73 ± 0.12% day-1 SGR. Hence, the addition of Kepok banana peel flour as a feed raw material is quite effective in supporting the growth of common carp.

Eri silkworm pupae as fish meal replacement in common carp (Cyprinus carpio L.) feed in indoor aquaria

Eri silkworm (Samia ricini D.) pupae based fish feed, for common carp (Cyrinus carpio L.) advanced fry, in indoor aquaria was evaluated with eight different diets. Eri silkworm pupae meal (ESWPM) based fish feeds influenced the growth of common carp significantly. Fortnightly growth measurements of the carp in eight treatments showed maximum in ESWPM alone and in ESWPM 100 per cent treatments. The proximate nutrient and amino acid composition varied in the fish feed diets. ESWPM based fish feed recorded significant impact on the carp with reference to its weight gain, specific growth rate, feed conversion ratio, and relative growth rate.

Effects of Alien Organisms on Growth of Common Carp, Cyprinus carpio Cultivated in Earthen Ponds

The experiment was conducted at Agricultural Research Station- Aquaculture Unit- Agriculture College- Basrah University in six earthen ponds (600 m3). The stady inclouding of alien organizms effect on growth of common carp Cyprinus carpio. Using an agricultural shadow as a filtering fabric was put in inlets pipes (T1), while T2 without filters. Fishes was daily feeding by a commercial sinking pellets manufactured by Agricultural Consultant Office belonging to Agriculture College, With a ratio of 3% from fishes weight. Total length and weight of fishes were measured at the beginning and at the end of the experiment. The weight of subsamples for fishes were taken periodically and daily feed changed after each weighing. At the end of the experiment the alien organism in all ponds were collected, classified and weighed individualy except shrimp. Results of current experiment revealed that there were significant differences (P≤0.0.5) in final weigh, wight increment, daily growth rate and feed conversion rate between fishes reared in ponds with and without filter. These differences may be related to differences in numbers and weighs of alien organisms in these ponds (97 individuals of six fish species in ponds without filter comparing with two individuals of one fish species in ponds with filter, and also 16314 g of shrimp in ponds without filter comparing with 440 g in ponds with filter). From the results of the current experiment, it can be concluded that culturist must used filters in inlet pipes of their ponds to prevent or reduced the entering of alien organizms to these ponds.

Different quantities of manganese oxide nanoparticles incorporated feed on the growth and haematological traits of common carp Cyprinus carpio var. communis

In recent times, nanoparticles have been used as raw ingredients for biofertilizers, mineral supplements in animal feed, and pharmaceuticals. Manganese plays a vital role in enhancing fish's growth and biological function. The present research work aimed to analyze the various quantities of manganese oxide nanoparticles on common carp growth and its haematological traits. Synthesized manganese oxide (Mn3O4) nanoparticles were illustrated using UV-visible Spectroscopy (UV-Vis), Scanning Electron Microscope (SEM), Energy Dispersive X–Ray Spectroscopy (EDAX), X–Ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR). Six different feeds were prepared by incorporating different quantities of manganese oxide nanoparticles (Feed I (control-0mg), Feed II(3mg/100g), Feed III(6mg/100g), Feed IV(9mg/100g), Feed V(12mg/100g), and Feed VI(15mg/100g)) with common ingredients such as groundnut oil cake, fish meal, tapioca flour, and wheat flour. On the completion of 21 days, feed utilization and haematological characteristics of Common carp were assessed. The UV-Vis showed that manganese oxide nanoparticles exhibit strong adsorption peaks at 220nm. SEM image observed at the wavelength range from 9.22 nm to 9.35 nm. The size of the particles was in the 45-55 nm range. The EDAX spectrum recorded two peaks between 0.40 and 6 kev. The XRD graph shows that the diffraction peaks are indexed as 103, 004, 213, 204, 303, and 215. FT-IR spectrum measured at the wavelength range from 500-4000cm-1. Most of the growth parameters and haematological parameters were higher in feed III, containing 6mg of Manganese oxide nanoparticles. Therefore, results show that manganese oxide incorporated feed enhances the growth and haematological traits in common carp compared to control feed.

Transcriptome analysis provides new insights into ovarian follicle growth in common carp (Cyprinus carpio)

Ovarian growth is a critical phase of oogenesis that involves several events such as steroidogenesis, lipid deposition, and vitellogenesis. Although many studies have been conducted on fish ovarian growth and development, the molecular mechanisms that contribute to steroidogenesis and lipid deposition in common carp, the world's third largest freshwater aquaculture fish, remain elusive. In this study, transcriptome analyses were performed on ovaries from Yellow River carp at three different developmental stages: primary growth stage (PG), pre-vitellogenesis stage (PV), and mid-vitellogenesis stage (MV). A total of 22,511 genes were detected, and of these 122, 253, and 278 were differentially expressed genes (DEGs) when comparing PG to PV, PV to MV, and PG to MV stages, respectively. Gene ontology (GO) and KEGG enrichment analysis showed that the DEGs were mainly involved in steroidogenesis (e.g., fshr, cyp19a1a, hsd3b and foxl2b), lipid deposition (e.g., lpl, slc27a6, fabp4, acsl1a, agpat3, plpp3 and dgat1b), and vitellogenesis (e.g., lrp13, plb1, dgkaa and pik3r1). We also identified many signalling pathways involved in ovarian growth, including steroid hormone biosynthesis, the phospholipase D signalling pathway, glycerophospholipid metabolism, the Notch signalling pathway, the TGF-βsignalling pathway, and the Wnt signalling pathway. qPCR results of 9 representative genes related to steroidogenesis and lipid deposition verified the reliability of the generated RNA-seq data. Finally, a potential model for the formation of lipid droplets and yolks in the ovaries of common carp was proposed. Overall, the data from this study will contribute to further research on the molecular regulatory mechanisms of ovarian growth and development in common carp and other fish species.

Effect of Aquatic Plants as a Biofilter on Water Criteria and Common Carp Growth Performance in Aquaculture Intensive System

The experiment was conducted in the field of the College of Agriculture, University of Tikrit, for the period from 14/6/2022 to 14/8/2022 inside a semi-exposed building (gable) with four treatments. Each treatment included three replicates, and each replicate included (6) fishes in a closed bio-aquatic system, by weight 14.15±1.22, 13.8±0.72,13.9±0.78, 13.7±0.93g for T1, T2, T3 and T4 in 12 ponds respectively. On a filtration tank representing the biological and mechanical filter in an intensive aquatic system with a capacity of 100 liters each, three aquatic plants were grown (lentils, Azolla, Ceratophylom), except for the control treatment, which was similar to all treatments except for the presence of aquatic plants. The water was treated in a mechanical filter unit through thick sponge layer, then directing the water to the biological treatment by means of crushed gravel, in addition to the aquatic plants to filter the dissolved organic pollutants. The results showed a significant effect of aquatic plants at (p ≤0.05) on dissolved oxygen DO (mg / liter), pH, total dissolved salts (TDS), nitrate NO3, nitrite NO2, and ammonia. The biological characteristics of aquatic plants are impacted by modifications to the physicochemical properties of the water. There was a significant improvement in weight gain (G.W), relative growth (RGR), specific growth of fish (SGR), and feed conversion efficiency (FCR) for treatments T2, T3, and T4 compared with control treatment. There was a significant difference when using aquatic plant in the percentage of protein compared to the control treatment. No significant differences were observed on blood biochemical parameters. While the result of the correlation or interactions between water characteristics with growth parameters for Common carp fish showed significant effects at a significant level (P ≤0.05) and (P ≤0.01).

Effect of Artificial Aeration by Cascade Type Bamboo Baskets on Water Quality in Fish Culture

Dissolved oxygen in intensive fish culture system acts as the critical factor of water quality, a primary concern in enhancing fish production. The effect of artificial aeration on water quality in intensive carp culture system using various management practices has been studied. Addition of oxygen into pond water with high stocking density for improved water quality and production of catfish (Loyacano, 1974), feed utilization and growth in common carp (Singh et al., 1980) and Indian major carps (Vijajan and Verghese, 1986) have been found effective.

Utilization the Aquatic Plants as a Filtration Media in A Closed Bio-Aquatic System to Improve Water Quality and Common carp Growth Performance

The experiment was conducted in the animal production field, College of Agriculture, Tikrit University, for the period from 14/6/2022 to 14/8/2022 inside a semi-exposed building with three treatments. Each treatment included three replicates, and each replicate included (6) fish in a closed bio-aquatic system, by weight 13.75±1.09, a filtration tank representing the mechanical and biological filter in an intensive aquatic system with a capacity of 100 liters each, two aquatic plants were grown Water thyme (Hydrilla Verticillata), Torpedo grass (Panicum Repens), except for the control treatment, which was similar to all treatments except for the presence of aquatic plants. The water was treated in a mechanical filter unit through sponge layer, then directing the water to the biological treatment by means of crushed gravel, in addition to the aquatic plants to filter the dissolved organic pollutants. The results showed a significant effect of aquatic plants at (p ≤0.05) on pH, Cloredait (Cl) nitrate (NO3,) nitrite (NO2), and ammonia. Water properties reflect to the biological system of organisms. There was a significant improvement in gain weight (G.W), specific growth rate (SGR), and feed conversion efficiency (FCR) for treatments T2 and T3 compared with control treatment. While, the result of the correlation or interactions between water characteristics with growth parameters for Common carp fish showed significant effects at (P ≤0.05) and (P ≤0.01) level.

Determining the Potential Roles of Branched-Chain Amino Acids in the Regulation of Muscle Growth in Common Carp (Cyprinus carpio) Based on Transcriptome and MicroRNA Sequencing.

Branched-chain amino acids (BCAAs) can be critically involved in skeletal muscle growth and body energy homeostasis. Skeletal muscle growth is a complex process; some muscle-specific microRNAs (miRNAs) are involved in the regulation of muscle thickening and muscle mass. Additionally, the regulatory network between miRNA and messenger RNA (mRNA) in the modulation of the role of BCAAs on skeletal muscle growth in fish has not been studied. In this study, common carp was starved for 14 days, followed by a 14-day gavage therapy with BCAAs, to investigate some of the miRNAs and genes that contribute to the regulation of normal growth and maintenance of skeletal muscle in response to short-term BCAA starvation stress. Subsequently, the transcriptome and small RNAome sequencing of carp skeletal muscle were performed. A total of 43,414 known and 1,112 novel genes were identified, in addition to 142 known and 654 novel miRNAs targeting 22,008 and 33,824 targets, respectively. Based on their expression profiles, 2,146 differentially expressed genes (DEGs) and 84 differentially expressed miRNA (DEMs) were evaluated. Kyoto Encyclopedia of Genes and Genome pathways, including the proteasome, phagosome, autophagy in animals, proteasome activator complex, and ubiquitin-dependent protein catabolic process, were enriched for these DEGs and DEMs. Our findings revealed the role of atg5, map1lc3c, ctsl, cdc53, psma6, psme2, myl9, and mylk in skeletal muscle growth, protein synthesis, and catabolic metabolism. Furthermore, miR-135c, miR-192, miR-194, and miR-203a may play key roles in maintaining the normal activities of the organism by regulating genes related to muscle growth, protein synthesis, and catabolism. This study on transcriptome and miRNA reveals the potential molecular mechanisms underlying the regulation of muscle protein deposition and provides new insights into genetic engineering techniques to improve common carp muscle development.

THE EFFECT OF MUSTARD GREENS POWDER AND PELLETS ON THE GROWTH OF COMMON CARP (Cyprinus carpio)

Common carp is a fish consumption that is relatively easy to cultivate since it tends to be adaptive (easy to adapt to its environment and resistant to various types of diseases). One of the protein requirements for the growth of fish seeds can be obtained from mustard greens. Furthermore, the abundant availability of mustard greens in Kajoran Village can be an alternative feed if developed as carp feed. The purpose of this study is to determine the effect of mustard greens powder on the growth of common carp (Cyprinus carpio); besides, to determine the best concentration of mustard greens powder on the growth of common carp. This study was conducted in January-February 2022. The research method used an experimental method with treatment P1 (control), P2 (mustard green powder 25%), P3 (50%), P4 (75%), and P5 (100%). The results of giving the concentration of mustard green powder for the growth of common carp show a significant difference and it can increase the growth of carp. Furthermore, the best treatment is achieved in the P3 treatment (50% mustard green powder) with an average weight gain of 1.120 g. From the results of this study, it is expected that the people of Kajoran Village can use mustard greens well for carp cultivation with a concentration of 50% pellets and 50% mustard green powder. In addition, further research is needed on the manufacture of pellets from mustard green powder to make it easier for farmers to feed.

A comparison of growth of a vulnerable species, common carp, Cyprinus carpio (Actinopteri: Cyprinidae), from two different reservoir types in the same river basin

Context The mechanisms underlying regional differences in growth parameters of common carp, Cyprinus carpio Linnaeus, 1758 (Actinopteri: Cyprinidae), are not yet fully understood, because comparisons among them have been made post hoc. Aims To simultaneously compare growth of common carp between sexes and between regions: Demirköprü Reservoir (DR) and Marmara Lake (ML), which have different structures (lowland type vs highland type) and are proximate to each other in the same river basin (Gediz River Basin). Methods Length-frequency distributions, length–weight relationships and three growth models (von Bertalanffy growth function (VBGF), Gompertz growth function (GGF) and Robertson growth function (RGF)) were used for both sexes and all individuals in reservoirs. Key results As none of the best-fitting models used among these growth models clearly suggested a ‘clear winner’ (Akaike’s weight (wi) &gt; 0.9), the model-averaged multi-model inference (MMI) was used for the first time for common carp. Conclusions Asymptotic length obtained from MMI for all individuals in ML (lowland type) was statistically higher than that in DR (highland type) (P &lt; 0.05). Implications Based on the maximum observed length and the mean L∞ obtained from MMI, the common carp population in the DR can be considered threatened by overfishing.

Impact of varying amounts of Moringa oleifera seed powder in the diet on a few aspects of common carp growth L. Cyprinus carpio

The current study was conducted in experimental cages in a mud pond, First Agricultural Research and Experiment Station, Agriculture College, Al-Muthanna University, to determine the effect of different levels of Moringa oleifera seed powder on the diets of common carp. A total of 75 common carp fish with an average weight of 65.08±0.42 g were used; it was randomly distributed to 5 treatments with three replicates (5 fish for each replicate). The fish that were fed on experimental diets was divided into five equal therapies in terms of protein percentages, different in the proportions of adding Moringa seed powder; the rate of seeds added to the treatments was 0, 0.5, 1, 1.5 and 2%, respectively, the fish were fed on the experimental diets at 5% of the live weight, divided into four meals a day. The results showed a significant superiority of T2 and T3 treatments compared with other therapies on growth parameters (final weight, weight gain, daily growth rate, specific and relative), and give the best feed conversion ratio, the highest food conversion and protein efficiency ratio. Indicates that adding Moringa seed powder to diets at rates of 0.5 and 1% led to fish growth promotion and increased utilization of feed intake. Keywords: Moringa oleifera, growth parameters, common carp Cyprinus carpio L.

Pyrroloquinoline quinone supplemented diet enhances metabolism, feed intake and growth in common carp (Cyprinus carpio Linnaeus, 1758) reared at low temperature

A pilot study was conducted to delineate the potential of dietary pyrroloquinoline quinone (PQQ) on Cyprinus carpio Linnaeus, 1758, at water temperature of 12-14oC using a recirculatory system with water flow rate of 1.8 l min-1. Six isonitrogenous (32% CP) and iso-caloric (16.7 MJ kg-1) diets were prepared with varying levels of PQQ viz. control (0 mg kg-1), T1 (0.2 mg kg-1), T2 (0.4 mg kg-1), T3 (0.6 mg kg-1), T4 (0.8 mg kg-1) and T5 (1.0 mg kg-1). Two hundred and sixteen common carp juveniles were distributed randomly into control and five treatment groups in triplicates with 12 fish per tub and fed twice daily at satiation level for 30 days. Results indicated that dietary quinone at 0.8 mg kg-1 significantly increased the feed intake and weight gain, specific growth rate (SGR), feed conversion ratio (FCR) as well as protein efficiency ratio (PER) were significantly higher (p&lt;0.05) than non-quinone fed group. The thyroid hormone levels as well as digestive and metabolic enzyme activities were significantly higher (p&lt;0.05) in treatments than in control. The superoxide dismutase (SOD) activity in liver was significantly higher (p&lt;0.05) in T1, T2 and T5. Catalase activity in gill was significantly higher (p&lt;0.05) in control and lowest in T3 and T4. Therefore, quinone can be used as a feed additive for enhancing feed intake, enzymatic activities and growth during winter. Keywords: Feed additive, Feed intake, Metabolism, Pyrroloquinoline quinone, Winter feeding

Evaluation of optimum dietary protein requirement for maximum growth of common carp ( Cyprinus carpio ) fingerlings

A 90-day feeding trial was carried out to investigate the effect of varying dietary protein on growth performance, health status, intestinal enzyme activity, carcass composition and intestinal histomorphology of common carp (Cyprinus carpio) fingerlings for defining the optimum dietary protein. Five groups were fed with different crude protein content: T1 (36%), T2 (38%), T3 (40%), T4 (42%) and T5 (44%). Each group was run in triplicate with 10 fingerlings per tank. The group fed with 38% crude protein showed significantly (p < 0.05) higher specific growth rate, daily weight gain, weight gain percentage and low feed conversion ratio as compared to groups which had a protein content lesser/higher than 38%. The body composition and digestive enzyme activity were significantly higher in T2 followed by T1 (36%). The excretion of total ammonia and orthophosphate was also lowest in T2. The intestinal histomorphology examination revealed significantly increased absorptive area in T2 compared to other treatment groups. The findings indicate that optimum amount of dietary protein is crucial for achieving maximum growth, and feeding fish with diet containing excess or lesser than optimum protein content leads to lesser growth besides more excretion thereby affecting the quality of water.