Protozoan parasites of wild and cultured sea bass, Dicentrarchus labrax (L.), from the Mediterranean area

Abstract. In a parasitic survey of wild and cultured sea bass, Dicentrarchus labrax (L.), thirteen protozoan species were found. Ectoparasites included two ciliates ( Trichodina spp.), one dinoflagellate ( Amylodinium sp.) and one zooflagellate ( Cryptobia sp.). Endoparasites were represented by members of Apicomplexa ( Hemogregarina sp., Eimeria spp.). Microsporea (unidentified species) and Myxosporea ( Myxobilatus sp., Ceratomyxa spp., Sphaerospora dicentrarchi, Sphaerospora testicularis). Myxobilatus sp., Eimeria spp. and the microsporean were exclusively found in wild fish, whereas Amyloodinium sp. and Hemogregarina sp. were only detected in cultured fish. Data on prevalence and intensity of infections and on the location in the host are provided. The potential importance of protozoan parasites for sea bass culture is discussed.     

Long photoperiod delayed spawning and increased somatic growth in gilthead seabream (Sparus aurata)

The effects of extended photoperiods, mimicking the longest day of the year, were studied in 1- and 2-year seabream. The photoperiod regimes started in late July, 36 and 39 days after the summer solstice and continued for 11 months, well beyond the natural reproductive season of December–March. Regime 1 (long day, 15.5L:8.5D), which used natural and fluorescent light, reduced the incidence of maturity in both year classes and females did not spawn although some gonadal development was observed. Among all 1-year sampled fish of regime 1, a maximum of 5% became spermiating males (March) and 5% reached the yolk granule stage of vitellogenesis (VO3; 250–400 μm diameter) by May. Among 2-year sampled fish of regime 1, 45% became spermiating males and 25% were females, which reached the advanced vitellogenesis stage (VO4; 400–600 μm) by April. Regime 2 (skeleton photoperiod), consisting of natural light and a 1.5-h pulse of fluorescent light during the period 14–15.5 h after sunrise, postponed gonadal development and spawning for up to 3 months. In this regime, a maximum of 80% of 1-year sampled fish were spermiating males in February and a maximum of 10% were VO3 stage females in March. In the sampled 2-year fish, the maximum levels were 50% spermiating males in February and 25% VO3 stage females in March. Control fish, which were exposed to the natural photoperiod (29°34′N), spawned during their natural season. The maximum levels for 1-year sampled control fish were 95% spermiating males and no females in December, while among 2-year sampled fish, maxima of 75% males in February and 45% VO4 stage females in November. Final average weights of photoperiod treated fish (1-year=430 g—regime 1, 400 g—regime 2; 2-year=582 g—regime 1, 518 g—regime 2) were significantly greater (p<0.05) than control fish (1-year=341 g; 2-year=476 g). Daily feed consumption (g/100 g fish) dropped from an average of 1.83 to 0.93 g for 1-year fish during August–December and from 0.88 to 0.54 g for 2-year fish during the same period. This was correlated with reduced autumn and winter water temperatures (26–20°C summer to winter change) and increased fish weight in all treatments. Daily feed consumption was also affected by the onset of spawning in the control and regime 2 (skeleton photoperiod) treatments of both 1- and 2-year fish. The efficiency of feed utilization (FCR) and protein and energy retention were all affected by the photoperiod regimes and followed the same pattern of decrease as weight gain, regime 1 (long day)>regime 2 (skeleton photoperiod)>control.     

Notes on kidney-infecting species of the genus Sphaerospora Thélohan (Myxosporea), including a new species S. gobionis sp.nov., and on myxosporean life cycle stages in the blood of some freshwater fish

Abstract Freshwater fish in Czechoslovakia were examined for species of the genus Sphaerospora Thélohan, 1892 and for myxosporean life cycle stages in the blood. In addition to perch infected with S. pectinacea Bocharova & Donets, 1974, renal tubules of seven host species harboured thus far unidentified Sphaerospora species. A new species, S. gobionis sp.nov. is described from renal tubules of Gobio gobio. In populations of Gobio gobio, Tinea tinea and Rutilus rutilus harbouring infections with different Sphaerospora species, organisms identified as mobile myxosporean life cycle stages were detected in the blood, where they undergo a proliferative cycle. These organisms were reminiscent of stages in the blood of common carp fingerlings, supposedly identical with Sphaerospora renicola Dyková & Lorn. It is possible that the blood stages found in the three cyprinid hosts represent stages of the life cycle of their respective Sphaerospora species. If this is correct, further studies may show if the presence of proliferative stages in the bloodstream is a character distinctive of the genus Sphaerospora.     

Induced spermiation in 3-year-old sterlet, Acipenser ruthenus L.

Spermiation in 3‐year‐old sterlet, Acipenser ruthenus (L.), males maintained under warm water conditions was induced by intramuscular injection of either (i) (D‐Ala⁶)‐GnRH‐ProNHEt (Kobarelin); (ii) mammalian GnRH analogue+metoclopramide (Ovopel); or (iii) human chorionic gonadotropin (Biogonadyl). The volume of milt, sperm concentration and motility were measured. A higher percentage of spermiating males was obtained after Kobarelin or Ovopel treatment (81.8% and 77.7% respectively) in comparison with fish treated with Biogonadyl (40.0%). However, only stimulation with Ovopel guaranteed motile spermatozoa in all spermiating males. Moreover, treatment with Ovopel resulted in the highest average milt volume, sperm concentration and motility. The average total number of motile spermatozoa (milt volume×sperm concentration×sperm motility) per individual was 0.99×10⁹, 5.31×10⁹ and 0.02×10⁹ after stimulation with Kobarelin, Ovopel or Biogonadyl respectively. Our data indicate that Ovopel is a good stimulator of spermation in sturgeons. Moreover, the time of sexual maturation could be significantly reduced in sturgeons maintained in cages under warm water conditions.     

Lectin histochemical studies on Sphaerospora sp. (Myxosporea) from Italian brown trout, Salmo trutta L.

A Sphaerospora sp. (Myxosporea) infection (presumably S. truttae ) was identified on a trout farm in northeastern Italy. Parasites were detected in kidneys from infected brown trout, Salmo trutta L., over a 2-year period. Extrasporogonic, sporogonic stages and mature spores were simultaneously detected in the same fish. Traditional diagnostic methods for Sphaerospora spp. rely on the detection of the myxosporean developmental stages in Giemsa-stained kidney smears or haematoxylin-eosin stained tissue sections. A histochemical method was employed where 10 biotinylated lectins (Con-A, DBA, SBA, GS-I, PHA-P, LEA, PWM, RCA₁, WGA and UEA-I) and the avidin-biotin-peroxidase complex (ABC) were used on Sphaerospora -infected brown trout renal tissues and kidney imprints. Five monoclonal antibodies against PKX (Mab12, MabA3, MabC5, MabD4 and MabB4) were also tested. A lectin glycoconjugate binding pattern for Sphaerospora spp. is presented. This staining method shows that SBA lectin ( Glycine max agglutinin) is a useful tool for the detection of the Sphaerospora spp. Only MabB4 bound some of the most mature sporogonic stages. In contrast Mabs12, A3, C5 and D4, and GS-I lectin ( Griffonia simplicifolia agglutinin) did not stain any of the Sphaerospora spp. stages, but did bind very specifically to the sporogonic and extrasporogonic stages of PKX, the causative agent of proliferative kidney disease (PKD).     

Seasonal changes in sperm production and quality in the red porgy Pagrus pagrus (L.)

Cultured red porgy Pagrus pagrus (L.) males (n=6) were sampled every 2 weeks for milt, in order to monitor changes in sperm quality parameters during a whole spawning period. On 11 January 2001, 60% of the fish were spermiating, increasing to 100% in mid‐February and dropping to 30% by mid‐April. Sperm density showed a slight increasing trend, with mean values ranging between 8.6 and 23.7×10⁹ spermatozoa mL^?1. Sperm motility percentage exhibited a significant improvement during the spawning season (analysis of variance (anova ) P=0.0001). The duration of forward motility for the major part of the monitoring period ranged between 2 and 4 min. Red porgy spermatozoa maintained their viability for many days after whole storage of milt at 4°C. During the monitoring period there were significant changes in the mean duration of sperm survival after cold storage, ranging from 5 to 12 days. The total volume of expressible milt was maximal on 28 March, increasing from a mean value of 1.7 mL to 5.3 mL kg^?1. Milt production of captive‐reared red porgy does not appear to be limiting, when compared with the volume of expressible milt produced by other cultured marine fishes.     

野生与养殖银鲳幼鱼氨基酸含量的比较

比较了野生与养殖银鲳幼鱼氨基酸的含量。结果显示,野生与养殖银鲳鱼体中均以谷氨酸含量最高,组氨酸含量最低,必需氨基酸中均以赖氨酸含量最高,并且四种呈味氨基酸的含量由高到低的顺序均为谷氨酸>天冬氨酸>甘氨酸>丙氨酸。养殖银鲳鱼体中脯氨酸含量较野生银鲳明显升高(变异系数为11.16%),但丝氨酸、酪氨酸及八种必需氨基酸(缬氨酸、蛋氨酸、亮氨酸、异亮氨酸、苏氨酸、苯丙氨酸、赖氨酸及精氨酸)的含量均较野生银鲳低。养殖银鲳氨基酸总量(54.17 g/100 g干物质)与必需氨基酸总量(27.16 g/100 g干物质)均分别低于野生银鲳鱼体中的氨基酸总量(57.92 g/100 g干物质)与必需氨基酸的总量(30.04 g/100 g干物质),变异系数分别为4.74%与7.13%;而呈味氨基酸总量与野生银鲳相比差异较小,变异系数仅为2.66%。养殖银鲳与野生银鲳鱼体中必需氨基酸总量与总氨基酸的比值(EAA/TAA)均较高,分别为50.14%与51.87%。此外,养殖与野生银鲳鱼体中的呈味氨基酸与总氨基酸(DAA/TAA)的比值同样较高,分别为37.92%与36.82%。     

Induced spawning in perch, Perca fluviatilis L. using carp pituitary extract and HCG

Induced spawning in Eurasian perch, Perca fluviatilis L., was studied using human chorionic gonadotrophs (hCG) or acetone-dried common carp pituitary with or without hCG. The dose administered to fish was 5700 IU hCG kg^-1 or 4.0 mg kg^-1 carp pituitary with or without 500-700 IU hCG kg^-1 for females and 2850 IU hCG kg^-1 or 2.0 mg kg^-1 carp pituitary with or without 250-350 IU hCG kg^-1 for males. There were no statistically significant differences in quantity of milt in treated and control groups, although the best result was observed when males were treated with a triple injection of hCG and carp pituitary extract. Male spermiating success, expressed as a quantity of milt, was negatively correlated with fish weight. All females treated in this experiment had oocytes at the same division, so time of ovulation was highly synchronous. Spawning success, expressed as a spawning effectivity coefficient (S_c), was highest in fish treated with the triple injection. Spawning methods described in this paper were successful, even though hormones from another order of fish were used.     

Effects of partial or total fish meal replacement by agricultural by-product diets on gonad maturation, sex steroids and vitellogenin dynamics of African catfish (Clarias gariepinus)

The establishment of the first sexual maturation was characterized in African catfish (Clarias gariepinus) in order to study the efficiency of replacement of fish meal (FM) by diets composed of local vegetable ingredients. Four diets were formulated containing decreasing levels of FM (50-0% for diet 1 to diet 4) and increasing proportions of vegetable ingredients (50-100%). Gonadosomatic index (GSI), diameter and percentages of developmental stages of oocytes, plasma sex steroids and vitellogenin dynamics were investigated from February to June using one-year-old fish. Fish were individually tagged, and 12 individuals from each diet were investigated monthly. Replacement of FM with plant ingredients did not affect the GSI neither in males, nor in females. All males were spermiating, and no abnormal gonads were found. In females, GSI and percentages of advanced stages of oocytes decreased during the dry season, indicating seasonal changes in gonad development. Moreover, oocytes were in late exogenous vitellogenesis, but no final maturation stages were observed, whatever the diet. Higher plasma levels of E2 in females and of androgens (T and 11-KT) in both sexes were observed in fish fed diet 4 than in those receiving diet 1 depending on the season. Levels of plasma E2 and ALP (indicator for vitellogenin) in males did not differ among treatments and seasons suggesting no phytoestrogenic activity. The results showed that total replacement of FM by vegetable diets composed of groundnut oilcakes, bean and sunflower meals has no deleterious effect on the onset of sexual maturation in African catfish but, may stimulate the sex steroid production and in turns may potentially exert some positive actions on reproductive success.     

Comparison of fatty acid contents of wild and cultured rainbow trout <Emphasis Type="Italic">Onchorhynchus mykiss</Emphasis> in Turkey

Abstract:   The total lipid content and fatty acid composition were determined in the flesh and skin of wild and cultured rainbow trout in Turkey. The effect of diet content was also investigated on cultured trout. Gas chromatography-mass spectrometry (GC-MS) was used for fatty acid analyses. Total lipid content of skin was higher than flesh in both types and when compared appreciably higher in cultured fish. The predominant fatty acid was palmitic acid (C16:0) in saturated fatty acids and oleic acid (C18:1n-9) in monounsaturated fatty acids. The amount of eicosapentaenoic acid was double in wild and docosahexaenoic acid (DHA) 1.5 times higher in cultured fish flesh. The n-3/n-6 ratio was higher in cultured fish than wild fish. The levels of palmitic, oleic, linoleic (C18:2n-6) and palmitoleic (C16:1n-7) acids were high in skin. The level of EPA was the same in skin of wild fish but 5.5 times higher in cultured fish, whereas the proportion of DHA in skin was lower for wild and 3.5 times higher in cultured fish. Wild fish had a high level of linoleic, arachidonic (C20:4n-6) and linolenic (C18:3n-3) acids. The total amount of n-3 and n-6 polyunsaturated fatty acids was higher in flesh of wild fish than cultured fish, contrary to skin of cultured fish. The data obtained demonstrated that fatty acid composition of cultured fish did not depend on that of feed.     

Renal sphaerosporosis in the common carp Cypnnus carpio L.

Abstract. Sphaerospora angulata Fujita, 1912, has been identified as a frequent renal parasite of cultured carp populations in Hungary. Its prevalence ranged from 10 to 50% in the pond farms surveyed. The youngest carp infected were 2¹/₂–3 months old. Infections were not common in one-summer fish and tended to become less frequent with increasing age of the host.
The developing stages of S. angulata are found in the contorted tubules of the trunk-kidney but never invade the parenchymal tissue of the trunk or head-kidneys. The pansporoblasts developing in the wide proximal segment of the renal tubules, and the spores arising from the pansporoblasts are typically coelozoic parasites, for they apparently do not damage the tubular lining epithelium, nor its brush border. The main adverse effect of S. angulata is probably depression of resistance owing partly to deprivation of the host of nutrients secreted by the glomeruli and partly to mechanical obstruction of the distal tubular segments.     

The dynamics of gonad growth and ascorbate status in yellow perch, Perca flavescens (Mitchill)

Yellow perch, Perca flavescens (Mitchill), caught in the wild (Grand St Marys Lake, Ohio) and cultured in the laboratory were used to examine the relationship between gonad development and the concentration of ascorbic acid in ovaries, testes, liver and kidney. In wild fish the ovary had concentrations of ascorbate twice as high (75-102 μg g^-1) as the testis (28-48 μg g^-1), and when the differences in gonadosomatic indices between sexes were accounted for, females deposited 10-fold more of this essential nutrient in gonads than did males. Yellow perch cultured intensively throughout the gonadal recrudescence had shown a decrease of ascorbate concentration in the kidney, liver and ovary during winter, most likely due to the low dietary level of the vitamin. Diet enrichment with ascorbic acid resulted in a dramatic increase of ascorbate in ovary and other tissues. Incorporation of ascorbic acid may take place during the late vitellogenesis, and this vitamin deserves to be studied as a quality indicator in fish eggs.     

Comparison of the growth performance of offspring from cultured versus wild populations of arctic charr,Salvelinus alpinus (L.), kept at three different temperatures

The effects of three different temperatures on the growth and maturation of the offspring of cultured versus wild populations of juvenile arctic charr (Salvelinus alpinus L.) were investigated. The fish (start weight 17 g) were reared for 5 months at constant temperatures of 12, 14 and 16°C under a continuous light regime (LD24:0). Growth performance was significantly influenced by both temperature and source population. The offspring from the farmed fish displayed significantly higher mean weights at all temperatures compared with the offspring from the wild fish. The results indicate that the optimal temperature for growth (T_opt) decreases with increasing fish size in the offspring of both cultivated and wild fish. Significant differences in length–weight relationship were found, with the offspring of wild fish displaying higher condition factor throughout the experiment. The results demonstrate that the offspring from multiple generation farmed population of arctic charr are better adapted to high temperatures compared with the offspring (F₁ generation) from a wild population of arctic charr, and the former are also able to maintain growth at higher temperatures. There was a significant difference in maturation between the two populations, as the offspring from cultured fish displayed significantly lower level of maturation: 0%, 4% and 2% mature compared with 24%, 40% and 42% in the offspring from wild fish at temperatures of 12, 14 and 16°C respectively. The offspring from farmed strains of arctic charr thus appear to be the most suitable population for aquaculture.     

微山湖四鼻须鲤养殖群体和野生群体肌肉营养成分分析

利用常规肌肉营养测定方法,分析了微山湖四鼻须鲤(Cyprinus carpio)野生群体和养殖群体各10尾的肌肉营养成分。结果显示,四鼻须鲤野生群体的粗蛋白(18.05%)和钙(0.69mg/g)含量高于养殖群体的17.27%和0.49mg/g,野生四鼻须鲤的粗脂肪含量(1.02%)低于养殖群体(1.86%),两者的水分、粗灰分和磷含量基本相同,肌肉中氨基酸组成基本一致,均含有18种氨基酸,4种呈味氨基酸总量分别为6.71%和6.08%(鲜样),必需氨基酸指数(EAAI)分别为73.35和67.44,其构成比例符合FAO/WHO的标准。     

中华鲟血清卵黄蛋白原水平的初步观察

通过碱不稳定性蛋白结合磷法测定不同年龄中华鲟(Acipenser sinensis)血清中磷含量,以磷的含量变化反映卵黄蛋白原(VTG)变化情况。实验鱼为人工养殖0.5、1、2、3、4、5、6、8、9、10龄中华鲟和野生成熟中华鲟,共81尾,其中8尾野生雌鱼在人工繁殖前后各取样2~4次,共测97个血液样本。结果显示:低龄中华鲟VTG含量较低,最低值在5龄,含磷量为(4.6±1.6)mg/L,5龄后增加,成熟后达到最大,含磷量为(52.0±4.5)mg/L。在性腺不同发育时期,雌性个体在Ⅱ~Ⅴ期VTG的含量增加,Ⅱ~Ⅲ期增加速度较快,随后变缓,Ⅴ期达到最高水平,Ⅵ期降低;而雄性个体在Ⅱ~Ⅳ期VTG的增加量很少,Ⅳ期达到最高水平,含磷量为(28.7±12.2)mg/L。繁殖雌鱼产前VTG含量最高,含磷量为(62.5±8.7)mg/L,产后低于产前。此外,发现产后鲟鱼卵巢液中含量低于其血清中含量,但高于其他年龄组血清中的水平。本实验表明淡水养殖的中华鲟有可能达到性成熟。     

Fatty acid compositions in muscles of wild and cultured ocellate puffer Takifugu rubripes

Lipid contents and fatty acid compositions were compared among 110 muscle samples of Japanese wild, Japanese cultured, and Chinese cultured ocellate puffer Takifugu rubripes. The effects of diet on muscle lipids in cultured ocellate puffer were also investigated. There was no noticeable difference between the wild and cultured fish with regard to the lipid content, but there were significant differences in the fatty acid composition ratio such as C16:0, C16:1n-7, and C20:4n-6. Moreover, the percentages of the fatty acids C18:2n-6 and C22:5n-3 were correlated with those in the diet. These results suggest that the muscle lipid content was not affected by diet, whereas fatty acid composition was affected. There were significant differences in fatty acid composition among Japanese wild fish, Japanese cultured fish, and Chinese cultured fish. The results suggest that the fatty acid composition is applicable as a tool to distinguish between wild and cultured ocellate puffer as well as those cultured in Japan and China.     

不同年龄野生和养殖兴凯湖翘嘴鲌肌肉营养成分分析

为评定营养价值、建立种质标准以及研制人工配合饲料,对2龄、4龄和6龄兴凯湖翘嘴鲌(Culter alburnus)野生和养殖群体的肌肉营养成分和营养品质进行了分析比较,结果显示,2龄兴凯湖翘嘴鲌野生和养殖群体肌肉营养成分含量无显著差异(P>0.05);4龄、6龄野生群体的水分和粗蛋白含量显著高于养殖群体(P<0.05),粗脂肪含量显著低于养殖群体(P<0.05)。与常见养殖鱼类相比,野生兴凯湖翘嘴鲌Ca和P含量较高。野生和养殖群体的氨基酸组成一致,甘氨酸含量最高,谷氨酸和赖氨酸次之。4龄、6龄野生群体氨基酸总量(TAA)、必需氨基酸总量(EAA)和鲜味氨基酸含量显著高于养殖群体(P<0.05)。结果表明,兴凯湖翘嘴鲌野生与养殖群体蛋白质含量较高,均含有丰富的氨基酸,具有较高的营养价值和食用价值;野生群体肌肉营养价值和肉味鲜美程度明显优于养殖群体,且随年龄增长差异更鲌加明显。在配制兴凯湖翘嘴鲌人工饲料时,应适当添加限制性氨基酸蛋氨酸和胱氨酸,以提高其营养价值;适当添加甘氨酸和谷氨酸,以提高养殖鱼体风味。     

The effect of whole body lipid on early sexual maturation of 1+ age male chinook salmon (Oncorhynchus tshawytscha)

Early sexual maturation of male chinook salmon (maturation 1 to 4 years prior to females in the same age class) results in reduced effectiveness of stock enhancement programs and a financial loss to the salmon farming industry. Previous studies in Atlantic salmon have shown that the age of maturity in males is affected by growth and/or body energy stores, but the relative roles of these two factors are not well understood. Therefore, an experiment was designed to determine when spermatogenesis was initiated, to characterize the endocrine changes during the onset of puberty in male salmon, and to determine if the level of whole-body lipid affects the incidence of early male maturation in a wild stock (Yakima River) of 1+ spring chinook salmon. Fry were fed a commercial diet from February until August and were then divided into groups of 320 fish (mean weight, 5.6 g) and fed one of five experimental diets (two replicate groups/diet) containing 4%, 9%, 14%, 18% or 22% lipid and 82%, 77%, 73%, 69%, or 65% protein for 13 months. Fish were reared on natural photoperiod and ambient temperature (6°C to 16°C), and pair-fed to a level based on the tank with the lowest feed consumption. Fish were weighed monthly and sampled to determine body composition, pituitary follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels, plasma insulin-like growth factor I (IGF-I) levels, and stage of gonadal development.

Throughout the experimental period the mean fish weight was similar among treatment groups. However, from December through the end of the experiment in the following September, maturing males were significantly larger than nonmaturing fish. Initial lipid levels in 0-age experimental fish were near 6%, which is similar to wild fish of the same stock and age captured in the Yakima River during August. Fish fed diets containing more than 4% lipid increased in whole-body lipid content during the first 2 months of feeding and then maintained at relatively constant levels during the course of the experiment. Whole-body lipid levels for the dietary treatment groups averaged 5.6%, 7.1%, 8.2%, 9.4%, and 9.6% from October through the following September.

Based on histological examination of the testes of experimental fish, type B spermatogonia and primary spermatocytes were first observed in some of the yearling males during November. These were designated maturing males. Pituitary FSH levels were significantly higher in maturing than nonmaturing males at this time and for the remainder of the study. Pituitary FSH levels increased as spermatogenesis proceeded in maturing fish, whereas pituitary LH levels increased in maturing 1+ males only during July and August, when testes were in late stages of spermatogenesis and in September during spermiation. Plasma IGF-I levels were significantly higher in maturing males than nonmaturing fish from December through the end of experiment. Since maturing males were significantly larger than nonmaturing fish of both sexes from December through September, the difference in IGF-I levels could be due to differences in growth or due to maturation.

The percentage of maturing males was significantly influenced by whole-body lipid, increasing from 34% in fish fed the 4% lipid diet to 45% in fish fed the 22% lipid diet. These data suggest that whole-body lipid levels influenced the incidence of maturation of male spring chinook salmon. In addition, both endocrine and histological indicators suggest that maturation was initiated in males approximately a full year prior to the time the fish will spawn.     

Comparative fatty acid profiles of wild and farmed tropical freshwater fish rohu (<Emphasis Type="Italic">Labeo rohita</Emphasis>)

The proximate composition of the whole body and the fatty acid composition of the liver, muscle, eye and brain of wild and cultured rohu (Labeo rohita) were analyzed. The cultured species was found to have significantly (P < 0.05) higher lipid contents than its wild counterpart. The saturated (SFA) and monounsaturated (MUFA) fatty acid contents were significantly higher in the cultured species, whereas the n-6 and n-3 polyunsaturated fatty acid (PUFA) levels were higher in the wild species. Fatty acids C16:0 and C18:1 n-9 were the principal fatty acids of the SFAs and MUFAs, respectively, identified in the analyses. Docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid were the predominant PUFAs in both groups, and all three were found to be present at significantly (P < 0.05) higher levels in the wild species. Erucic acid (C22:1 n-9), which was the predominant fatty acid (30.76%) in the feed, was detected only at low levels in muscle (0.30%), liver (1.04%) and eye (1.28%) of cultured fish tissue.