Metabolic responses of the white shrimp, Penaeus vannamei, to ambient ammonia

Juvenile shrimp were individually exposed during 24 h to 0.007 (control), 0.36, 1.07, and 2.14 mmol/l total ammonia-N at 28 degrees C and 39 ppt salinity. After 22 h of ammonia-N exposure, oxygen consumption was measured for 2 h, and then hemolymph, hepatopancreas, and muscle tissues were sampled. Oxygen consumption, and levels of lactate and glycogen in the hepatopancreas increased significantly at the highest ammonia-N concentration. Concentration of oxyhemocyanin, acylglycerol, and cholesterol in hemolymph, and lactate in muscle decreased significantly in the group exposed to the highest ammonia levels. The changes observed in hemolymph and tissue metabolic fuels suggest a reduced use of carbohydrate through anaerobic metabolism and an increase in the use of lipids to satisfy the metabolic demand.     

Nitrogenous excretion and arginase specific activity of kuruma shrimp Marsupenaeus japonicus exposed to elevated ambient nitrite

Nitrogenous excretion and arginase specific activity were measured while Marsupenaeus japnoicus Bate (7.4±1.2 g) were exposed to 0 (control), 0.36 and 1.39 mM nitrite at 30‰ (g kg⁻¹) salinity for 24 h. Excretions of total-N, organic-N, urea-N, and ammonia-N increased significantly with an increase of ambient nitrite. Arginase specific activities of hepatopancreas and hemolymph increased directly with ambient nitrite. The fact that M. japonicus following exposure to 1.39 mM nitrite increased its arginase specific activity indicated an argininolysis in reducing joint toxicities of metabolic ammonia and incorporated nitrite.     

Hepatopancreas gluconeogenesis during anoxia and post-anoxia recovery in Chasmagnathus granulata crabs maintained on high-protein or carbohydrate-rich diets

C. granulata is a semiterrestrial crab that lives in the mesolittoral and the supralittoral zones of estuaries and faces hypoxia and anoxia when exposed to atmospheric air. The carbohydrate or protein content of the diets administered to the crabs induced different metabolic adjustments during anoxia and post-anoxia recovery period. During the first hour in anoxia a marked increase in L-lactate concentration in hemolymph was induced, followed by a reduction in its levels accompanied by two peaks in hepatopancreas gluconeogenic capacity. Anoxia exposure did not induce a reduction in the hepatopancreas phosphoenolpyruvate carboxykinase activity in either dietary group. Our results suggest that in anaerobiosis this crab uses the conversion of lactate to glucose in hepatopancreas to maintain the acid-base balance and the glucose supply. In post-anoxia recovery, the fate of L-lactate is the hepatopancreas gluconeogenesis in high protein maintained crabs. On the other hand, in the crabs maintained on carbohydrate-rich diet the L-lactate levels decreased gradually in the hemolymph during the post-anoxia recovery; however, the hepatopancreas gluconeogenesis did not increase. In both dietary groups, an increase in the gluconeogenic capacity of hepatopancreas occurred at 30 h of post-anoxia recovery.     

Short Communication

Anaerobic metabolism and oxygen carrying-capacity of white shrimp ( Penaeus vannamei ) exposed to short term (three days) and long term (two weeks) moderate hypoxia (2-2.6 mg/L) was investigated. Glucose and lactate levels in hemolymph increased under both hypoxic conditions, indicating an activation of anaerobic pathways during the two-weeks exposure period. In muscle, no differences of glucose and lactate levels were observed between the control group and the exposed groups. In animals exposed to hypoxia for two weeks, hemocyanin and copper in hemolymph were higher than in animals under normoxic conditions or exposed for three days. These results indicate that an increase in oxygen carrying-capacity in shrimp is evident only after a sustained condition of hypoxia. Copper levels in the hepatopancreas decreased in both hypoxic conditions, suggesting a mobilization of copper stores for hemocyanin synthesis. These results indicate that penaeid shrimp can tolerate moderate hypoxic conditions by physiological adaptations, such as anaerobic metabolism and increased oxygen carrying-capacity. These adaptations require an adequate dietary supply of proteins and copper for hemocyanin synthesis and of carbohydrates for anaerobic metabolism.     

Short Communication

Anaerobic metabolism and oxygen carrying-capacity of white shrimp (Penaeus vannamei) exposed to short term (three days) and long term (two weeks) moderate hypoxia (2-2.6 mg/L) was investigated. Glucose and lactate levels in hemolymph increased under both hypoxic conditions, indicating an activation of anaerobic pathways during the two-weeks exposure period. In muscle, no differences of glucose and lactate levels were observed between the control group and the exposed groups. In animals exposed to hypoxia for two weeks, hemocyanin and copper in hemolymph were higher than in animals under normoxic conditions or exposed for three days. These results indicate that an increase in oxygen carrying-capacity in shrimp is evident only after a sustained condition of hypoxia. Copper levels in the hepatopancreas decreased in both hypoxic conditions, suggesting a mobilization of copper stores for hemocyanin synthesis. These results indicate that penaeid shrimp can tolerate moderate hypoxic conditions by physiological adaptations, such as anaerobic metabolism and increased oxygen carrying-capacity. These adaptations require an adequate dietary supply of proteins and copper for hemocyanin synthesis and of carbohydrates for anaerobic metabolism.     

Metabolism of amino acids during hyposmotic adaptation in the whiteleg shrimp, Litopenaeus vannamei

The penaeid prawn, Litopenaeus vannamei, was employed to investigate intracellular isosmotic regulation in situations where invertebrates encounter hyposmosis. Hemolymph osmolality was first analyzed to confirm osmoregulatory conditions in the experimental animals, followed by analysis of amino acids in muscle and hemolymph using high-performance liquid chromatography. Total muscle amino acid levels decreased when hemolymph osmolality was extremely low, whereas glycine and l-serine levels increased in the hemolymph. These results suggest that tissue amino acids were released into the hemolymph to lower the osmolality of the tissues for purposes of low-salinity adaptation. Next, oxygen consumption and ammonia excretion rates were examined, and the O/N ratio was determined. Oxygen consumption levels and ammonia excretion rates increased, and the O/N ratio decreased when the animals were exposed to low salinity. These results suggest that amino acids were abundantly consumed as an energy source when animals were exposed to low salinity. To confirm the consumption of particular amino acids, the specific activity of l-serine ammonia lyase was also examined. Specific activity was highest when l-serine levels in the hemolymph were highest. Thus, it appears that l-serine levels increased under hyposmotic conditions due to the consumption of l-serine as an energy source. It was concluded that particular amino acids as osmolytes are likely metabolized as energy sources and consumed for purposes of hyposmotic adaptation.     

Hemolymph oxygen content,oxyhemocyanin, protein levels and ammonia excretion in the shrimp Penaeus monodon exposed to ambient nitrite

Subadult Penaeus monodon (21.03±3.19 g) were exposed individually in sea water (30 mg·ml^-1) to 0.02 (control), 1.04, 5.02, 10.11 and 20.06 mg·l^-1 nitrite-N for 24h. Hemolymph pH, partial pressures of oxygen and carbon dioxide, bicarbonate concentration, oxyhemocyanin and protein levels, and whole animal ammonia-N excretion and nitrite-N uptake were determined. Ammonia-N excretion and hemolymph oxygen partial pressure increased, whereas hemolymph pH, HCO ₃ ^- , oxyhemocyanin, protein and the ratio of oxyhemocyanin/protein levels decreased with increasing ambient nitrite-N. It is suggested that accumulated nitrite of P. monodon following exposure to ambient nitrite causes reduction of oxyhemocyanin, protein and the ratio of oxyhemocyanin/protein in the hemolymph, and affects nitrogen metabolism and acid-base balance at low hemolymph pH.Abbreviations bw body weight - EC₅₀ concentration reducing growth rate by 50% that of controls - LC₅₀ median lethal concentration - nitrite-N nitrite concentration measured as nitrogen - PO₂ partial pressure of O₂ in hemolymph - PCO₂ partial pressure of CO₂ in hemolymph - sw sea water - ww wet weight     

Superoxide radical production in response to environmental hypoxia in cultured shrimp

Markers of oxidative stress in response to hypoxia and reoxygenation were assessed in Pacific white shrimp (Litopenaeus vannamei). Adult shrimp were either exposed to hypoxia (1 mg O(2)/L) for 6, 12, or 24 h followed by 1-h reoxygenation, or exposed to hypoxia for 24 h followed by 1- to 6-h reoxygenation. In all cases, shrimp maintained at constant normoxia were used as controls. Spectrophotometric techniques were applied to analyze lactate concentration, superoxide radical (O(2)(*-)) production, lipid peroxidation (TBARS), and antioxidant capacity status in muscle, hepatopancreas, and gill samples. Results indicate differences among tissues, even under control conditions. O(2)(*-) production and TBARS levels were higher in hepatopancreas than in gill or muscle. No effect of exposure to hypoxia was found. However, reoxygenation following exposure to hypoxia was found to affect the oxidative metabolism of muscle and hepatopancreas from cultured shrimp. Lactate concentration and O(2)(*-) production increased while antioxidant capacity decreased in hepatopancreas and muscle in the first hours of reoxygenation. This could translate into tissue damage, which may significantly jeopardize the commercial aquaculture product.     

Physiological roles of free D- and L-alanine in the crayfish Procambarus clarkii with special reference to osmotic and anoxic stress responses

Under hyper-salinity stress from freshwater to 17 and 25 ppt seawater, red swamp crayfish Procambarus clarkii largely accumulated D- and L-alanine together with glycine, L-glutamine, and L-proline in both muscle and hepatopancreas. The increases of D- and L-alanine in muscle were the highest in all amino acids and reached 6.8- and 5.4-fold, respectively, from freshwater to 25 ppt seawater. These results indicate that both D- and L-alanine are the most potent osmolytes for intracellular isosmotic regulation in crayfish as well as other crustaceans thus far examined. Under anoxia stress below 0.1 mg/l dissolved oxygen for 12 h and subsequent recovery in normoxia for 12 h in freshwater, 17 and 25 ppt seawater, muscle ATP decreased dramatically in all salinity levels and almost depleted in seawater. Along with the decrease of muscle glycogen level, the significant increase of L-lactate was found in muscle, hepatopancreas, and hemolymph for each salinity level, suggesting the transport of L-lactate from muscle into hepatopancreas via hemolymph. Under anoxia, D- and L-alanine also largely increased in both muscle and hepatopancreas for each salinity level. The increase was much higher in seawater than in freshwater. Thus, both D- and L-alanine are possible to be anaerobic end products during prolonged anaerobiosis of this species.     

Superoxide dismutase activity in juvenile Litopenaeus vannamei and Nodipecten subnodosus exposed to the toxic dinoflagellate Prorocentrum lima

The toxic effect of the dinoflagellate Prorocentrum lima on juvenile American whiteleg shrimp Litopenaeus vannamei and giant lion-paw scallop Nodipecten subnodosus was evaluated. Organisms were exposed to three densities (500, 2000, or 5000 cells mL(-1)), superoxide dismutase activity and soluble protein in the hepatopancreas and muscle were determined at 1, 6, 24 and 48 h after challenge. Shrimp exposed at 5000 cells mL(-1) significantly increased SOD activity in the hepatopancreas at 1 h post-challenge, whereas enzymatic activity in muscle significantly increased at 24 h at all densities. Scallops exposed to 500 and 2000 cells mL(-1) showed significant SOD activity increase in hepatopancreas at 24 and 12 h, respectively. Mortality at 48 h was 100% in scallops exposed to 5000 cells mL(-1). Shrimp showed higher levels of SOD activity than scallops. Soluble protein content in the shrimp hepatopancreas was significantly higher at densities of 500 and 2000 cells mL(-1) at 6 and 1 h, respectively. Soluble protein content in the scallop hepatopancreas was higher than control values at 1 h after challenge. In this study, 500 cells mL(-1) was enough to trigger SOD activity in two benthic species exposed to the toxic dinoflagellate P. lima.     

Phosphamidon, methylparathion and dichlorvos impact on tissue oxidative metabolism in penaeid prawn, Metapenaeus monoceros

Changes in oxidative metabolism of hepatopancreas and muscle tissues of penaeid prawn, Metapenaeus monoceros was studied, following its exposure to selected organophosphorous insecticides phosphamidon, dichlorovos and methylparathion. The OPI are found to inhibit the activity levels of acetylcholinesterase, succinate dehydrogenase, isocitrate dehydrogenase, pyruvate dehydrogenase, lactate dehydrogenase and cytochrome-c-oxidase and cause accumulation of acetylcholine in the hepatopancreas and muscle tissues. These changes in the activity levels of selected oxidative enzymes during insecticide exposure in these tissues of prawn indicates the shift in the metabolic emphasis from aerobic to anaerobic conditions and is interpreted as a functional adaptation to insecticide induced metabolic stress. These observed changes at cellular level pave way for successful survival of prawns in insecticide polluted environ.     

Hemolymph ammonia, urea and uric acid levels and nitrogenous excretion of Marsupenaeus japonicus at different salinity levels

Arginase specific activity, hemolymph ammonia, urea and uric acid levels and nitrogenous excretion were measured in Kuruma shrimp Marsupenaeus japonicus (7.29±1.16 g) acclimated to different salinities of 18‰, 26‰, 34‰ and 42‰. Arginase activity in the gill, midgut, hepatopancreas and muscle were higher and lower for the shrimp in 42‰ and 18‰, respectively. Arginase specific activity of hemolymph was higher at 34‰. Hemolymph ammonia, urea and uric acid increased directly with salinity, and excretions of total nitrogen (total-N), organic nitrogen (organic-N) and urea-N increased directly with salinity. However, ammonia-N excretion and nitrite-N excretion were inversely related to salinity. Ammonia-N accounted for 90.9%, 75.0%, 67.9% and 38.5% of total-N, whereas urea-N accounted for 3.1%, 4.5%, 7.9% and 10.9%, and organic accounted for 4.2%, 19.8%, 23.1% and 50.4% of total-N excreted by the shrimp in 18‰, 26‰, 34‰ and 42‰, respectively. Significantly higher levels of hemolymph urea and uric acid together with an increase in arginase activity indicated that ureogenesis and uricogenesis are activated for M. japonicus in hyperosmotic conditions.     

Physiological and metabolic variations in Carcinus mediterraneus (Crustacea: Decapoda) parasitized by Thelohania maenadis (Microspora: Microsporida): An ecophysiopathological approach

This paper examines the influence of Thelohania maenadis (Protozoa: Microsporida), a muscle microsporidian, on certain features of the metabolism of Carcinus mediterraneus (Crustacea: Decapoda). Comparison of biochemical parameters reveals that only hemolymph total protein and glucose levels are reduced significantly by this parasitic infection. Muscular effort results in a diminution of muscular glycogen and hemolymph glucose levels, while hepatopancreatic glycogen remains unaffected; lactate accumulates in the muscle tissue. Experimental variations in the environmental water temperature and salinity affect protein levels and metabolic indicators of carbohydrate metabolism. Proteinemia varies with temperature and salinity, but parasitic infection accentuates these variations. Glucose and lactate concentrations in the hemolymph are increased in healthy specimens after muscular effort, under conditions of increased temperature or hypoosmotic shock; microsporidiosis provokes the reverse of these tendencies, on a less pronounced scale. Hyperosmotic shock at high temperature leads to a slight reduction in glucose and lactate concentrations. The paper concludes with a discussion of the physiopathological significance of the results obtained as an expression of the effects of parasitism infestation.     

Changes in caridac output and hemolymph flow during hypoxic exposure in the gravid grass shrimp, <Emphasis Type="Italic">Palaemonetes pugio</Emphasis>

The cardiovascular response of decapod crustaceans to hypoxic exposure is well documented; however, information is limited concerning the influence of reproductive state on cardiovascular demands during hypoxic exposure. Given the additional metabolic demand of reproduction, we investigated the cardiovascular adjustments employed by gravid grass shrimp Palaemonetes pugio to maintain oxygen delivery during hypoxic stress. Cardiac output values were elevated in gravid compared to nongravid grass shrimp. Gravid grass shrimp were exposed to hypoxia and the stroke volume, heart rate, cardiac output and hemolymph flow were determined using video-microscopy and dimensional analysis. Oxygen consumption rates were determined using respirometry. There where no changes in the cardiac output values of gravid females until reaching 6.8 kPa O₂, with a significant redistribution of hemolymph flow at 13.7 kPa O₂. Flow was significantly decreased to the anterior lateral arteries that supply the ovaries and hepatopancreas, the anterior aorta and the posterior aorta. The redistribution of hemolymph flow away from these vessels results in an enhanced hemolymph flow to the sternal artery that supplies the ventral segmental system, the gills, the buccal apparatus and the ventral nerve cord. The data suggest that during hypoxic stress, gravid females place a priority on survival.     

Seasonal variation of energy metabolism in ghost crab Ocypode quadrata at Siriú Beach (Brazil)

The aim of this study was to analyze the seasonal variations of carbohydrate and lipid metabolism of the ghost crab Ocypode quadrata (Fabricius, 1787) on a sandy beach in the southern region of Brazil. Crabs and hemolymph samples were collected monthly in the field. Hepatopancreas, gills, gonads and claw muscles were used for glycogen determination. In males, blood glucose levels increased in the summer and in the winter. The glycogen values increased significantly in the hepatopancreas in the winter, but remained constant in the muscle, gonads and gills. In females, hemolymph glucose levels, glycogen values in the hepatopancreas and in the gills remained constant throughout the year; however, muscular glycogen increased in the spring and gonad glycogen decreased in the summer. Hemolymph triglyceride levels of males and females and total cholesterol of males decreased significantly in the spring. In females, a significant increase of total cholesterol levels was found in the winter. The findings suggest that in O. quadrata lipids seem to be an important reserve of energy used during reproduction, both in males and females, while glycogen may be used during periods of intense activity or fasting.     

Decreased genetic variation in metabolic variables of Litopenaeus vannamei shrimp after exposure to acute hypoxia

Concentration of proteins, carbohydrates, lactate, total lipids, acylglycerides, and carotenoids in shrimp were evaluated for their changes under acute hypoxia, and for their genetic variation under normoxic and hypoxic conditions. Proteins and lactate concentrations in muscle and hepatopancreas were significantly higher and carbohydrates in hepatopancreas were decreased in the hypoxic group. Family variances were significantly different only for proteins and carbohydrates in hepatopancreas in the normoxic group, indicating the existence of genetic variation for these traits. When family variances for each biochemical component were compared between normoxic and hypoxic groups, it was seen that most decreased. However, total variance was not significantly changed in response to hypoxia except for lactate (increased) and carotenoids (decreased) in hepatopancreas. The decrease in genetic variance without an increase in phenotypic variances in an acute response to hypoxia might be related to the known suppression of metabolic pathways that either use or produce ATP, which could result in a decreased expression of additive genes.     

Interstitial lactate,lactate/pyruvate and glucose in rat muscle before,during and in the recovery from global hypoxia

Background

Hypoxia results in an imbalance between oxygen supply and oxygen consumption. This study utilized microdialysis to monitor changes in the energy-related metabolites lactate, pyruvate and glucose in rat muscle before, during and after 30 minutes of transient global hypoxia. Hypoxia was induced in anaesthetised rats by reducing inspired oxygen to 6% O₂ in nitrogen.

Results

Basal values for lactate, the lactate/pyruvate ratio and glucose were 0.72 ± 0.04 mmol/l, 10.03 ± 1.16 and 3.55 ± 0.19 mmol/l (n = 10), respectively. Significant increases in lactate and the lactate/pyruvate ratio were found in the muscle after the induction of hypoxia. Maximum values of 2.26 ± 0.37 mmol/l for lactate were reached during early reperfusion, while the lactate/pyruvate ratio reached maximum values of 35.84 ± 7.81 at the end of hypoxia. Following recovery to ventilation with air, extracellular lactate levels and the lactate/pyruvate ratio returned to control levels within 30-40 minutes. Extracellular glucose levels showed no significant difference between hypoxia and control experiments.

Conclusions

In our study, the complete post-hypoxic recovery of metabolite levels suggests that metabolic enzymes of the skeletal muscle and their related cellular components may be able to tolerate severe hypoxic periods without prolonged damage. The consumption of glucose in the muscle in relation to its delivery seems to be unaffected.

     

Vitellogenin levels in hemolymph, ovary and hepatopancreas of the freshwater crayfish Cherax quadricarinatus (Decapoda: Parastacidae) during the reproductive cycle

The freshwater crayfish Cherax quadricarinatus is a tropical species of great interest for aquaculture. Vitellogenin (Vg), a lipoprotein precursor of the vitellum accumulated in spawned eggs, can be synthesized in the ovary and/or hepatopancreas of most crustaceans, being the hemolymph the way for transporting Vg throughout the reproductive cycle. Concentration of Vg in hemolymph, ovary and hepatopancreas of Cherax quadricarinatus adult females was measured by means of ELISA, specifically developed after purifying the native Vg. Measurements were made at four periods of the reproductive cycle: pre-reproductive, mid-reproductive, late reproductive and post-reproductive. Besides, both hepatosomatic (HSI) and gonadosomatic (GSI) indexes were determined in each period. Significant variations in Vg levels were detected in both hemolymph and hepatopancreas, being the highest values observed during the mid-reproductive period. Besides, such variations were positively correlated to the HSI. A positive correlation between Vg levels in hepatopancreas and ovary was also seen. These results support previous evidences about the central role of the hepatopancreas as a site of Vg synthesis in the studied species, together with the relevancy of hemolymph for transporting Vg from the hepatopancreas to the ovary. For aquaculture purposes, Vg monitoring in hemolymph could be used as a non-injurious method, to check the reproductive activity of C. quadricarinatus females.     

Metabolic responses in two species of crayfish (Parastacus defossus and Parastacus brasiliensis) to post-hypoxia recovery

The period of post-hypoxia recovery is essential for the rapid replenishment of energy reserves and for the removal of metabolic end products formed during hypoxia. Periods of post-hypoxia recovery were analyzed in two crayfish species, where Parastacus defossus is a fossorial species, and Parastacus brasiliensis lives in lotic environments with higher oxygen levels. After 4 h of hypoxia (2 mg O(2)/L), groups of animals were placed in tanks with oxygenated water and were then removed at intervals of 1, 3, 6, and 9 h. Hemolymph and tissues (hepatopancreas, muscle, and anterior and posterior gills) were extracted for the determination of glucose, lactate, free glucose, glycogen, total proteins, total lipids, arginine phosphate, and arginine. As expected, lactate levels were restored more rapidly in P. defossus than in P. brasiliensis. P. defossus restored its glycogen reserves of the hepatopancreas and muscle tissue. Free glucose was quickly restored in all tissues of both species. In relation to arginine phosphate reserves, P. defossus showed a greater ability to restore this metabolite in the hepatopancreas. Both species recovered their arginine phosphate reserves, but they also used this metabolite in longer periods of recovery. Mainly in P. brasiliensis the reserves of total lipids seem to be an important source of energy during the recovery period. The animals developed various metabolic strategies to post-hypoxia recovery, mainly P. defossus which restored its reserves more completely and more rapidly than did P. brasiliensis.     

饲料中添加雨生红球藻粉对三疣梭子蟹雌体卵巢发育、色泽、抗氧化能力和生化组成的影响

研究采用雨生红球藻(Haematococcus pluvialis)藻粉作为天然虾青素源, 配制4种不同虾青素含量(含量分别为0、26.60、41.62和81.37 mg/kg)的饲料(记为饲料1#—4#), 对三疣梭子蟹(Portunus trituberculatus)雌体进行为期45d的育肥实验, 研究其对雌蟹卵巢发育、色泽、抗氧化能力、免疫性能和生化组成的影响。结果表明: (1)育肥饲料中虾青素含量对雌蟹性腺指数(GSI)和肝胰腺指数(HSI)均无显著影响。(2)肝胰腺、卵巢和头胸甲中的总类胡萝卜素含量、红度(a*)值和黄度(b*)值均随饲料虾青素含量的升高而升高, 而3种组织的亮度(L*)值呈显著下降趋势(P<0.05)。(3)对抗氧化指标而言, 虾青素添加组(饲料2#—4#)血淋巴超氧化物歧化酶(SOD)和过氧化物酶(POD)活力均显著低于无虾青素组(饲料1#); 血淋巴中的总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSH-Px)及肝胰腺中的SOD和T-AOC活力均随饲料中虾青素水平升高而上升, 而血淋巴和肝胰腺中的丙二醛(MDA)含量呈下降趋势。(4)对免疫指标而言, 血淋巴和肝胰腺中的酸性磷酸酶(ACP)活力均在饲料4#组最高, 而饲料1#组血淋巴中的血蓝蛋白(Hc)含量显著高于其他组(P<0.05)。(5)对生化组成而言, 肌肉和肝胰腺中的总脂、总碳水化合物及卵巢中总脂含量均随饲料中虾青素含量的升高呈上升趋势, 饲料2#组卵巢中的总碳水化合物含量最高(P<0.05)。综上所述, 三疣梭子蟹雌体育肥饲料中添加虾青素对其卵巢发育无显著影响, 但可改善色泽和提高其抗氧化能力及可食组织中的总脂和碳水化合物含量, 三疣梭子蟹雌体育肥饲料中虾青素适宜含量为50 mg/kg饲料左右。