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Dietary Cd (dietary + cd)
Selected AbstractsEffect of dietary cadmium level on the growth, body composition and several hepatic enzymatic activities of juvenile yellow catfish, Pelteobagrus fulvidracoAQUACULTURE RESEARCH, Issue 7 2010Xiao-Ying Tan Abstract The present study was conducted to investigate the effect of dietary cadmium (Cd) level on the growth, body composition and several enzymatic activities of juvenile yellow catfish, Pelteobagrus fulvidraco. The experimental diets were formulated with CdCl2·2.5H2O at levels of 0, 0.01, 0.1 and 1.0 g kg,1 diet, resulting in four dietary Cd levels of 0.25 (control), 4.92, 48.57 and 474.7 mg Cd kg,1 diet respectively. They were fed to juvenile yellow catfish (mean initial weight: 3.26ą0.07 g, meanąSD) for 4 weeks. Weight gain, specific growth rate, feed intake and protein efficiency ratio tended to decline with increasing dietary Cd levels (P<0.05). In contrast, the feed conversion ratio was the lowest when the dietary Cd level was 0.25 mg Cd kg,1 diet. Dietary Cd levels significantly influenced body composition and Cd accumulation. Whole body and vertebrae Cd content generally increased as the dietary Cd levels increased (P<0.05). However, muscle Cd content was detected only in fish fed the diets containing the highest Cd level of the diet (P>0.05). Hepatic alkaline phosphatase, glutathione peroxidase and lactate dehydrogenase activities increased (P<0.05) with increasing dietary Cd level. Succinate dehydrogenase was very variant and not related to dietary treatments. Malic dehydrogenase activity showed no significant differences among the treatments (P>0.05). The present study provided for the first time the toxic assessment of dietborne Cd in yellow catfish, based on growth performance and the changes in hepatic enzymatic activities for the fish species. [source] The antioxidant capacity response to hypoxia stress during transportation of characins (Hyphessobrycon callistus Boulenger) fed diets supplemented with carotenoidsAQUACULTURE RESEARCH, Issue 7 2010Chih-Hung Pan Abstract This study aimed to determine whether dietary carotenoid (CD) supplements could affect the antioxidant capacity of characins Hyphessobrycon callistus upon hypoxia stress at live transportation. Two types of CD [astaxanthin (AX), ,-carotene (BC)] and their 1:1 combination (MX) at three concentrations (10, 20 and 40 mg kg,1) were supplemented, resulting in nine CD diets. After 8 weeks' rearing, the resulting fish were divided into two subgroups and exposed to hypoxia or normoxia. Hypoxia involved a gradual decrease in dissolved oxygen (DO) from 6.5 to <1.0 mg L,1. Normoxia was DO kept in saturation. Hypoxia led to an increase in the total antioxidant status (TAS), superoxide dismutase (SOD), glutathione peroxidases (GPx) and aspartate aminotransferase (AST) activity of blood serum in fish, but had no effect on alanine aminotransferase (ALT). Under hypoxia, fish fed CD diets had lower SOD, GPx and ALT activity than control fish, showing that dietary CD could increase the antioxidant capacity and protection of the liver. Dietary AX was more effective for antioxidant capacity than BC and MX when under hypoxia stress, because GPx, ALT and AST were lower in AX-fed fish. Except TAS, the other four enzyme activities showed decreasing trends with increasing dietary CD concentrations. [source] In vitro analysis of intestinal absorption of cadmium and calcium in rainbow trout fed with calcium- and cadmium-supplemented dietsJOURNAL OF FISH BIOLOGY, Issue 3 2006B. Baldisserotto The protective effects of dietary Ca2+ supplementation against Cd accumulation in rainbow trout Oncorhynchus mykiss fed with Cd-contaminated food were evaluated in relation to chronic changes in intestinal absorption rates. The changes were measured ,in vitro'. The control diet contained c. 20 mg Ca2+ g,1 food and 0·25 ,g Cd g,1 food; the experimental diets were supplemented with CaCO3 and Cd(NO3)2·4H2O to levels of 50 mg Ca2+ g,1 food and 300 ,g Cd g,1 food, alone and in combination. The Ca2+ and Cd absorption rates were measured using radiotracers (45Ca, 109Cd) at total Ca2+ and Cd concentrations of 3·0 and 0·12 mmol l,1, respectively in the intestinal saline. Chronically elevated dietary Cd caused a significant increase in Cd absorption rate by up to 10-fold at 30 days in the mid-intestine. The high Ca2+ diet prevented this up-regulation of Cd transport rate. Conversely, intestinal Ca2+ absorption was significantly increased by two- to five-fold by the Ca2+ -supplemented diet at 30 days in both the mid- and posterior intestine, and this effect was eliminated when Cd was simultaneously elevated in the diet. Ca2+ and Cd probably interact at common pathways and transport mechanisms in the intestine, though independent pathways may also exist. [source] Growth and Hematological Changes of Rockfish, Sebastes schlegeli (Hilgendorf) Exposed to Dietary Cu and CdJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2005Ju-Chan Kang Cd and Cu toxicological effect on growth and hematological parameters was investigated in juvenile rockfish Sebasres schlegeli after sub-chronic dietary Cd (0, 0.5, 5, 25, and 125 mg/kg) and Cu exposure (0, 50, 125, 250, and 500 mg/kg) for 60 d. In the experiment of dietary Cd exposure, weight and length SGR of the rockfish were significantly different from control, and a significant inverse relationship was observed between weight gain and the exposure concentration of dietary Cd at 25, 125 mg/kg (P > 0.05). Hematwrit and hemoglobin decreased significantly and were dose dependently in all Cd exposure. Glucose in serum was also increased significantly (P < 0.05). The concentration of total protein in serum was significantly lower than control at 5, 25, and 125 mgkg. No differences were observed in serum calcium concentration. Magnesium concentration in serum was increased signillcantly with dietary Cd concentration. In the experiment of dietary Cu exposure, Cu was inhibited weight gain and growth rate. No differences were observed in hematocrit, hemoglobin and RBCs compared to control. Contents of total protein, glucose, and Ca in serum remained stable. Mg concentration in serum was increased significantly at 500 mg/kg. 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