Effects of dietary vegetable oils on liver and gonad fatty acid metabolism and gonad maturation in gilthead seabream (Sparus aurata) males and females

A 20-week growth trial was conducted to investigate the effect of two dietary blended vegetable oils (VO) on liver lipogenic enzyme activity, liver and gonad lipid class composition and fatty acid profiles, serum sex hormones, and gonad morphohistology in gilthead seabream, Sparus aurata. Three groups of fish (BW _i 130.9 ± 3.1 g) were fed, close to satiation, three experimental diets: a control (CTRL) contained fish oil (FO) as the sole lipid source (100% FO) and two VO-blended diets in each 60% of FO was substituted by an equal mixture of cottonseed oil (CO), sunflower oil (SFO) and either linseed oil (LO) or soybean oil (SBO), designated as LO or SBO diet, respectively. Each diet was assigned to triplicate groups of fish. Results showed that all dietary treatments presented no significant (P > 0.05) differences in growth rate and feed conversion ratio for sexes combined. Enzyme activities of liver lipogenic enzymes of LO-fed fish (glucose-6-phosphate dehydrogenase (G6PDH), malic enzyme (ME) and fatty acid synthetase (FAS)) were not statistically (P > 0.05) different from those of CTRL fish. Only in the group of fish fed the SBO diet, G6PDH was slightly higher (P < 0.05) for both sexes, while ME showed a significant (P < 0.05) higher activity only in females relative to CTRL fish. Liver FAS enzyme activity remained unaltered among dietary groups. VO-fed fish recorded a significant (P < 0.05) increase in total lipid (TL) and triglyceride (TAG) contents in both liver and gonad, more pronounced in females than in males, concurrent with a significant (P < 0.05) decrease in cholesterol (CHL) and phospholipids (PL), more obvious for the SBO-fed fish, as compared to CTRL. The fatty acid (FA) composition of liver or gonad reflected that of the supplied diet and evidenced a significant (P < 0.01 or <0.05) alteration in the majority of individual FA in VO-fed fish compared to CTRL. There were decreased levels of ARA (20:4 n-6), EPA (20:5 n-3), and DHA (22:6 n-3) in VO-fed fish, more pronounced in females than in males, compared to CTRL. The liver and gonad FA profiles, for males and females, reflected the composition of the diet and showed sex variation in the output of multivariate principal component analysis (PCA). Feeding fish VO diets has also led to a significant (P < 0.05) reduction in serum estradiol level by 15.8 or 22.3% in LO- or SBO-fed fish, respectively, and in testosterone level by 7.7% in the latter dietary group only compared to the CTRL. Histomorphological examination of ovary and testis has indicated a relative retardation in oogenesis and spermatogenesis in VO-fed fish, less obvious in the LO-fed fish compared to CTRL. These results suggest a preference of LO over SBO blend diet in terms of liver lipogenic enzyme activity, liver and gonad lipid content, lipid class composition and fatty acid profile, serum sex hormones as well as gonad maturation. PCA analysis of gonads highlighted the importance of using a 100% marine FO diet for gilthead seabream broodstock for the recovery of a normal FA profile in gonads of fish, previously fed VO over the production cycle, to ensure successful spawning.     

Cultivation of whitebait (Galaxias maculatus) in Chile

The growth of commercial aquaculture in Chile generated an income of $2.300 million USD in exports in 2005. Currently, 15 different species are cultivated commercially, of which seven are native; these had returns of 185 million USD. Among these native species is Galaxias maculatus (whitebait), which is endemic to Chile and figures significantly in Chilean fishing statistics. Since the 1990s, the School of Aquaculture of the Universidad Catolica de Temuco has been developing cultivation of this native species. This work presents the state of the art of the cultivation of this fish.     

Variations in fatty acids composition of pikeperch (Sander lucioperca) liver with respect to gonad maturation

Abstract –  We examined seasonal variations in liver condition factor, total lipid and fatty acid composition of maturing pikeperch ( Sander lucioperca) from Lake Eğirdir, Turkey. The spawning of pikeperch in Eğirdir Lake started in March, continued very fast during May and gradually ended in July as determined by measuring the gonadosomatic index. The total lipid content of male and female liver reached its highest level in September and November (the end of dense feeding period during which temperature decreased sharply), but declined to the lowest level in May (just after spawning). The highest level of liver condition factor was observed in January and March during which gonads mature rapidly. Palmitic acid was the predominant saturated fatty acid (SFA) in female and male liver. The ratio of monounsaturated fatty acids (MUFA) was higher than that of polyunsaturated fatty acids (PUFA) in both sexes. Docosahexaenoic acid (22:6 n -3), eicosopentaenoic acid (20:5 n -3) and arachidonic acid (20:4 n -6) were the predominant PUFA. Seasonal variations in PUFA were more evident than that in other fatty acids. PUFA, especially the n -3 fatty acids ratio, increased to the maximum level during the sharp decreases in temperature (in November). However, the amount of PUFA decreased to the lowest level in reproductive period. The results suggest that the ratio of pikeperch liver fatty acids is influenced by gonad maturation and temperature variations and that pikeperch requires a large amount of PUFA and the n -3 fatty acids for the development of gonads.     

多刺裸腹溞孤雌溞的卵子发生

采用光镜和透射电镜技术观察多刺裸腹溞（Moina macrocopa）孤雌溞卵子的发生过程。根据卵母细胞细胞核的形态、卵黄的合成、积累情况及核物质的形态变化等观察结果,将卵子发生分为3个时期：卵原细胞期、卵母细胞期和成熟卵母细胞期。卵原细胞核大,胞质层薄,有少量线粒体分布,核物质浓缩为一团;卵母细胞发育的早期和中期细胞体积增大,细胞质层增厚,线粒体迅速增多,细胞核变圆,核物质分散成多块;后期卵母细胞胞质中开始出现大量卵黄颗粒和少量脂滴,细胞核边缘波浪化,线粒体空泡化,其中卵黄合成初期,核物质重新聚集在细胞核中央,在卵黄合成中期又分散开来;成熟卵母细胞质中充满卵黄颗粒,呈强嗜酸性,细胞核的形态呈不规则状,核物质分散。多刺裸腹溞生殖腺的外部形态随着生殖周期的变化而不同。在孤雌溞的整个生活史中生殖腺内卵子的发育经历了“同步一不同步一局部同步”的发育模式。发现1龄幼溞生殖腺中不存在卵原细胞,成龄溞的生殖腺有多个发育时期的生殖细胞并存。同时在亚显微水平上发现卵黄主要由线粒体演变而来,也通过吞饮作用吸收成熟的卵黄颗粒,内源与外源性共同作用形成卵黄。[中国水产科学,2006,13（4）：547—554]     

Helminth parasitism of Galaxias maculatus (Jenyns 1842) in southwestern Australia

Abstract –  One cestode, Ligula sp. [possibly Ligula intestinalis (L.)], one trematode, Diplostomum sp., and two nematode parasitic worms, Eustrongylides sp. [possibly Eustrongylides gadopsis (Royal Society of South Australia, 64, 340)] and Contracaecum sp. are reported from Galaxias maculatus inhabiting a permanent freshwater lake and two intermittently flowing, saline rivers in southwestern Australia. Worms infecting fish are all larval; the definitive hosts are piscivorous waterfowl. Ligula sp. infected 12% of fish in the lake. Effects of infection include reduced lifespan, significant weight reduction of gonads of males and females and body weight of females. Infection reduces the proportion of males that attain spawning gonad stage more severely than it does in females. The prevalence and intensity of Ligula sp. infection were much less in the rivers. The infection of Pseudogobius olorum (Sauvage 1880) by this cestode is reported for the first time in Western Australia. Trematodes were much more benign in their effect on G. maculatus .     

Ultrastructure of Goussia cruciata (Apicomplexa: Coccidia) infecting the liver of horse mackerel, Trachurus trachurus (L.), from Ibero-Atlantic waters

The ultrastructure of developmental stages of Goussia cruciata and the pathology they cause in the liver of Trachurus trachurus (Teleostei: Carangidae) caught off the Galician (North-West Spain) and Portuguese North Atlantic coasts are described. Each oocyst contained four ellipsoidal sporocysts, with two sporozoites. The sporocyst wall consisted of a thick and dense inner layer with transverse striations and a multi-lamellated outer layer formed by parallel dense internal bands alternating with lighter areas. The lamellae formed filamentous extensions of the wall. The sporocyst wall striation period was smaller than that observed in G. clupearum, which has a similar habitat. The dehiscence suture, characteristic of the genus, was present in the sporocysts of G. cruciata. The sporocysts were arranged in a symmetrical and characteristic cross shape. A large number of sporocysts with sporozoites were observed in direct contact with host liver cells. No macroscopic lesions were observed. In heavily infected fish, aggregations of oocysts were often enveloped in a 'yellow body' composed of amylopectin granules derived from the parasite and necrotic or aggregated host cells. Degenerating parasites were frequently observed in liver tissue. Host inflammatory cells were accumulated near some oocysts. The ultrastructure of the parasite, together with its strict host specificity, confirmed G. cruciata as a separate and valid species.     

中华绒螯蟹性腺香气品质评价方法

采用顶空固相微萃取-气-质联用技术(HS-SPME-GC-MS),对采自阳澄湖的特级、1级、2级的雄性及雌性中华绒螯蟹(Eriocheir sinensis)性腺中的香气成分进行了鉴定并以内标法对其定量。6种中华绒螯蟹样本中共检测到8类58种挥发物,采用主成分分析法(PCA)对标准化后的8类香气成分的浓度值进行分析,以主成分综合得分作为评价依据得到:特级和1级雌蟹性腺的香气品质最好,且呋喃类、醇类、芳香类、醛类4类成分对其贡献显著,是表征"高品质风味"的特征性香气成分;将性别因素统一考虑后,中华绒螯蟹等级越高,性腺香气品质越好;相同等级条件下,雌蟹性腺香气评分高于雄蟹。结果证实,主成分分析法可用于建立不同中华绒螯蟹性腺香气品质的评价模型。本研究旨在为深入探讨如何改善中华绒螯蟹的风味特性提供理论参考。     

3种饵料模式对中间球海胆生长、性腺产量和性腺品质的影响

研究了3种饵料模式对中间球海胆整个生长周期的生长速度及商品规格性腺产量和品质的影响。选取6月龄中间球海胆,以3种饵料模式海带(E1)、海带+贻贝(E2)、玉米+贻贝(E3)养殖至商品规格,期间每隔2个月对海胆的壳径和体质量进行测量,实验结束时,对海胆的性腺湿重、性腺水分和性腺颜色等进行测量和分析。结果显示:在海胆的各生长阶段,饵料模式对其壳径和体质量均具有极显著影响,3种模式下海胆的壳径和体质量均为E2>E1>E3。饵料模式对海胆大部分生长阶段壳径和体质量的特定生长率具有极显著影响,3种模式下海胆壳径和体质量的特定生长率均为E2≥E1>E3。饵料模式对商品规格海胆性腺产量和性腺品质具有显著或极显著影响,对于性腺湿重,E2模式[雌性:(7.58±1.21)g,雄性:(7.74±1.95)g]表现最优,其次是E1模式[雌性:(4.50±1.20)g,雄性:(4.87±1.02)g],最后为E3模式[雌性:(2.66±1.02)g,雄性:(2.32±0.75)g];对于性腺指数,E2模式(雌性:15.07%±1.84%,雄性:15.83%±3.01%)表现最优,其次为E1模式(雌性:10.49%±2.71%,雄性:11.27%±2.45%)和E3模式(雌性:12.48%±4.33%,雄性:12.78%±3.73%);对于性腺水分和性腺颜色,E2和E1模式表现最优,E3模式表现较差。饵料模式对不同性别海胆的影响差别较小。实验结果表明,单一投喂海带,中间球海胆即可获得较好的壳生长,而添加动物性蛋白可以明显的提高其体质量和性腺产量,海带+贻贝这一模式可应用于提高海胆养殖效率,而玉米对促进海胆的体生长和性腺产量和品质均无有益效果,即使添加动物性蛋白,玉米+贻贝这一模式也很难替代海带有效地养殖中间球海胆。     

紫海胆黄基本营养成分的分析与评价

为了测定紫海胆黄中的营养成分,并对其营养价值进行系统分析及合理评价,采用国家标准的生化测定方法以及美国化学分析方法(AOAC)检测海胆黄中的水分、粗灰分、粗蛋白质、粗脂肪、总糖、氨基酸、脂肪酸及矿物质。结果显示:海胆黄粉中水分含量(5.29±0.02)%,粗灰分(8.69±0.03)%,粗蛋白质(60.36±0.04)%,粗脂肪(25.32±0.09)%,总糖含量(0.044±0.002)mg/100 g;共检出18种氨基酸,总含量(46.50±0.89)%;谷氨酸含量最高,为(5.57±0.11)%;必须氨基酸占总氨基酸的(37.75±0.01)%;主要的限制氨基酸是色氨酸和亮氨酸;药效氨基酸占氨基酸总量的46.86%;蛋白质氨基酸评分(AAS)0.8,化学评分(CS)0.5;必需氨基酸指数(EAAI)为77.86;共检出30种脂肪酸,EPA(二十碳五烯酸)+DHA(二十二碳六烯酸)含量(2.43±005)%;海胆黄富含钾、磷、钠、镁、铁、锌等矿物质元素;常量元素中,磷元素含量最高,为(1 432.27±8.91)mg/100 g;微量元素中,锌元素含量最高,为(13.13±0.09)mg/100 g。研究表明,海胆黄中蛋白质含量丰富,氨基酸种类多、比例合理,脂质含量高且富含EPA、DHA等多不饱和脂肪酸,矿物质含量丰富。     

Comparative study of pikeperch Sander lucioperca (Percidae; Linnaeus, 1758) eggs and larvae from wild females or from captive females fed chopped marine fish

Morphometric characteristics, proximal composition and fatty acids profiles of eggs and larvae at hatching and mouth opening were studied as indicators for assessing the potential differences between spawns obtained from wild or captive females of pikeperch (Sander lucioperca). Captive females were acclimated to hatchery conditions and fed to satiation with chopped marine fish for more than a year, guaranteeing that captivity covered the full cycle of gonad maturation. The number of larvae obtained from the spawnings did not differ between captive and wild females, but both mean diameter and mean weight of the eggs collected from the captive females were significantly larger. Proximal compositions were similar in eggs and larvae from both groups, but fatty acids (FA) profiles showed striking differences: polyunsaturated FA consisted mainly of linoleic acid in eggs and larvae from wild females, while they consisted mainly of long chains of n-3 series in eggs and larvae from captive females. The diet of captive females largely modified the FA profiles of eggs and of hatching or mouth opening larvae, but did not affect the growth potential of early larvae, demonstrating that they were able to satisfy their early physiological needs regardless of the striking differences in their FA.     

Effect of dietary glucosylceramide from sea cucumber on plasma and liver lipids in cholesterol-fed mice

Various physiological functions of dietary glucosylceramides (GlcCer) have been reported, such as preventing colon cancer and improving skin barrier function. One potential GlcCer source used as a foodstuff is sea cucumber. In this study, our objective was to determine the effect of dietary GlcCer prepared from sea cucumber on plasma and liver lipids in cholesterol-fed mice. ICR mice were fed four different diets (control diet, sea cucumber GlcCer supplemented diet, high cholesterol supplemented diet, and high cholesterol + sea cucumber GlcCer supplemented diet). Dietary GlcCer decreased total cholesterol significantly in ICR mice. The mRNA expression of LDL receptor was increased significantly, while the expression of the gene CYP7A1, which is involved in bile acid formation, was decreased significantly compared with the control (diet without cholesterol). These results suggest that the expression of the cholesterol homeostasis gene in liver is modulated due to the cholesterol lowering effect of dietary GlcCer.     

Ulcerative dermatitis in wild dusky grouper Epinephelus marginatus (Lowe) from Libyan waters

In the period 2013–2015, wild dusky grouper, Epinephelus marginatus (Lowe), caught in Libyan coastal waters and ranging in size from 42 to 92 cm in total length, were observed to have distinctive skin lesions of unknown aetiology. Histopathologically, the lesions comprised a multifocal, unilateral or bilateral dermatitis, involving the epidermis, superficial dermis and scale pockets, and sometimes, in severe cases, the hypodermis. Severe lesions had marked epidermal spongiosis progressing to ulceration. Healing was observed in some fish. Bacteria and fungi could be isolated from severe lesions, although they were not seen histopathologically in early‐stage lesions. By contrast, metazoan parasite eggs were observed in the dermis and epidermis of some fish with mild and moderate dermatitis. Unidentified gravid digenean trematode parasites carrying similar eggs were also seen within the blood vessels of the deep and superficial dermis. The cause of this distinctive condition, termed dusky grouper dermatitis (DGD), and its potential impact upon already threatened Mediterranean wild dusky grouper populations and upon cultured grouper more widely have yet to be established.     

Gonadosomatic index and gonad histopathology of Gobius niger (Gobiidea, Teleost) from Bizerta lagoon (Tunisia): Evidence of reproduction disturbance

To evaluate the effect of anthropogenic pollution on fish reproduction in Bizerta lagoon, one of the largest Tunisian lagoons subjected to various anthropogenic and industrial pressures, the gonadosomatic index (GSI) and gonad histology of mature black goby (Gobius niger) were studied. Fish were collected during the breeding seasons from six stations differently impacted and in one reference station located at the seaward entrance of Ghar el Melh (GH) lagoon. In both sexes, we detected the presence of an overall weaker GSI in Bizerta lagoon than in control fish. These GSI alterations were accompanied by histopathological changes. In females, no significant differences in oocyte size were found across all the sample sites. However, a higher incidence of oocyte lesions (atretic oocytes, cytoplasmic retraction and karyoplasmic cluping) was found in stations located near agricultural activity zones. Histological observation of the testes revealed, as well, abnormalities in Bizerta lagoon fish: germ cells syncytium, vacuolated germ cells, melano-macrophage center and increase of gaps in the interstitium between lobules were detected with a high prevalence in stations influenced by industrial and/or urban activities. In addition, association between gonad fish histopathology and the presence of organic pollutants (DTT, PAHs and organotins) in sediment was noted. These results suggest that the chemical pollution in this lagoon may have adversely affected the gonad development of fish. In conclusion, this study is the first histological evidence of reproduction disturbance related to pollution pressure in a fish species inhabiting Bizerta lagoon. The high levels of gonad histopathology recorded raise concerns about the long-term health of fish populations in this lagoon.     

A test for interaction between brown trout (Salmo trutta) and inanga (Galaxias maculatus) in an artificial stream

Abstract –  The interaction between brown trout ( Salmo trutta ; fork length (FL) range 255–390 mm) and inanga ( Galaxias maculatus ; FL range 55–115 mm) was tested during summer through autumn in an artificial stream consisting of a single run-riffle-pool sequence with a natural food supply. Each experimental trial lasted for 15 days, and consisted of two brown trout and 50 inanga collected fresh from a nearby stream, with each species given prior residence in four replicate tests, totalling eight trials in all. In addition, two control trials (each 10 days), with 50 inanga in each, were run. Brown trout almost exclusively occupied the pool, whereas inanga occupied all habitat types, although in different proportions, when tested with and without brown trout. The proportion of inanga in the pool was appreciably lower in the experimental trials with brown trout than in the control trials with no brown trout; prior residence had no significant effect on inanga habitat use. Mortality of inanga attributable to predation by brown trout ranged from 0 to 40% with a mean of 14.5 ± 4.7%. The results suggest that habitat use and survival of inanga populations in small streams can be adversely affected by brown trout.     

淮河橄榄蛏蚌繁殖类型与性腺发育观察

对淮河橄榄蛏蚌（Solenaia oleivora Heude）繁殖类型和性腺发育特征进行了系统的研究。结果表明,橄榄蛏蚌为短期孵育型,繁殖期从3月至6月初,3—5月为繁殖高峰期,发现的最小怀幼雌蚌为2⁺龄;雌蚌内外2对鳃丝均可作为育儿囊,属于外鳃类的四生型,一次怀幼数量在134.9万~402.1万只。以雌蚌怀幼为第一判断标准,并结合卵巢组织切片,确认中国橄榄蛏蚌为一个繁殖周期内多次排卵繁殖类型。雌雄生长未见显著差异。橄榄蛏蚌性腺发育可分为增殖期、生长期、成熟期、排放期及休止期5个时期,卵巢和精巢发育基本同步。组织切片和扫描电镜均显示,卵母细胞通过直径约5μm的卵柄与滤泡壁相连;早期卵母细胞（直径小于17 μm）表面无细胞膜,而后期卵母细胞（约40 μm）表面出现明显的卵黄膜。橄榄蛏蚌精子为鞭毛型,头颈部呈子弹头形,最宽约2 μm;受精卵表面存在明显的卵膜孔,直径约1 μm,表明精子不能通过卵膜孔全部进入卵母细胞而受精。本研究成果为实现橄榄蛏蚌的人工繁育及利用奠定了科学基础,并为其他珍稀濒危蚌类的繁育保护提供借鉴。     

Comparative gonad histology and semen quality of normal (XY) and neo‐males (XX) of Atlantic salmon (Salmo salar)

With an overarching objective of improving the hatchery production of Atlantic salmon (Salmo salar) all‐female progeny, this study comparatively evaluated the reproductive parameters between normal (genotype XY) and neo‐males (genotype XX). Four normal (XY) and seven neo‐ (XX) males, from the same brood stock, distinguished by their ability to or lack of expressing semen, respectively, were comparatively evaluated. The left testicular lobe was used for histomorphometric analyses, while the right for semen collection and sperm quality analyses. Histomorphometric observations revealed that neo‐male testes are irregularly shaped, and have poorly formed seminiferous ducts, higher proportions of interstitial tissue and lower gonadosomatic index (p < .05). In addition, hypertrophied and cyst forming Sertoli cells were found in these individuals which collectively appear to form a physical barrier, precluding the semen collection by standard stripping techniques and reducing sperm quality. Particularly, semen motility (80.69 ± 2.4% and 57.2 ± 36.5% for XY and XX respectively) and duration of motility (99.31 ± 28.03 s and 66.84 ± 23.83 s for XY and XX respectively) of neo‐males were most compromised (p < .05). Interestingly, the TUNEL assay indicated no signs of apoptotic tissue suggesting that the histological differences may relate to delayed physiological/sexual maturity of neo‐males.     

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.     

花鱼骨 鱼种对11种蛋白质饲料原料的消化率

为获得花(鱼骨)对常用蛋白源的可消化性数据,按照"70%基础饲料+30%被测原料"的饲料配制方法,用三氧化二铬指标物,测定了花(鱼骨)鱼种对白鱼粉、褐鱼粉、四海豆粕、加佳豆粕、血粉、蚕蛹粉、啤酒酵母、菜籽粕、棉籽粕、花生粕、玉米蛋白粉等11种蛋白原料干物质和粗蛋白的表观消化率.结果表明:花(鱼骨)对11种原料的干物质和蛋白质表观消化率分别为54.84%～86.96%和69.17%～96.77%.其中自鱼粉、褐鱼粉、血粉以及豆粕、啤酒酵母等的干物质消化率较高,白鱼粉、褐鱼粉及豆粕、花生粕等的蛋白质消化率较高.     

黄鳝性腺发育的研究概况

黄鳝肉质鲜美 ,营养丰富 ,具有多种药用价值 ,在国内外市场很受欢迎。长期以来 ,由于人们过量捕捉野生黄鳝以及其水域环境受到污染 ,其自然资源已日益下降 ,远不能满足市场需要和出口创汇的要求。为此 ,黄鳝人工繁殖研究迫在眉睫 ,而性腺发育是鱼类繁殖的基础。早年 ,刘建康等[     

Improved vitellogenesis,gonad development and egg diameter in catfish (Pangasianodon hypophthalmus) supplemented with turmeric (Curcuma longa) powder

An experiment was conducted to study the effect of supplementing catfish (Pangasianodon hypophthalmus) with turmeric (Curcuma longa) on the vitellogenic capacity of the liver as a new method to improve reproductive performance in oviparous animals. The experimental catfish were assigned to a completely randomized design consisting of four doses of supplemental turmeric (0, 1.2, 2.4 and 4.8 g/kg feed) with 10 catfish with body weights ranging from 2 to 4 kg in each group. Blood samples were collected on days 0, 14, 28, 42 and 56 of turmeric supplementation to measure the concentrations of plasma oestradiol‐17ß and vitellogenin. The weights of the body, gonads and liver were measured on days 0, 28 and 56. The fecundities of the catfish were measured on days 28 and 56 of turmeric supplementation, and egg diameters were measured on days 28 and 42. The results showed that catfish supplemented with turmeric at a dose of 2.4 or 4.8 g/kg feed had higher growth rates, higher plasma oestradiol‐17β and vitellogenin concentrations, and higher gonad somatic index values and egg diameters. This is the first report demonstrating that the hepatoprotective activity of the curcumin in turmeric could be used to improve both vitellogenin synthesis, which improves nutrient deposition in the ovulating eggs, and the reproductive performance of teleost fish and oviparous animals.