Table 4.
Summary of efficacy studies with ATX in crustaceans
| Author(s) | Crustacean | Test item | Levels (mg ATX/kg) | Duration (days) | Endpoints | Results/conclusions |
|---|---|---|---|---|---|---|
| Chithambaran and Ayaril (2018) | Indian white shrimp, (Fenneropenaeus indicus) | ATX | 0, 250 | 45 | Colour of fresh and cooked shrimp by panel experts | Colour of shrimp (fresh and cooked) was significantly increased by ATX treatment |
| Daly et al. (2013) | Juvenile red king crabs (Paralithodes camtschaticus) | ATX from Haematococcus pluvialis, esterified | 0, 380 | 56 | Shell colouration | ATX significantly increased colour saturation (amount of hue) in treated animals as compared to controls (48.7 vs. 46.1), and reduced both colour hue (shade of colour, 20.8 vs. 27.2°) and brightness values (light vs. dark). Colour was quantified from digital photographs |
| Han et al. (2018) | Juvenile swimming crab, (Portunus trituberculatus) | ATX | 0, 30, 60, 90, 120 | 56 | Shell pigmentation | ATX supplementation significantly enhanced the redness (a*) of cooked crabs in a dose dependent manner. ATX concentrations of the whole body, shell and hepatopancreas showed a linear increase with increasing astaxanthin supplementation |
| Ju et al. (2011) | Pacific white shrimp (Litopenaeus vannamei) | ATX, ATX from H. pluvialis, esterified | 0, 25, 50, 75, 100, 150 | 56 | Measurement of colour of body and tail | Addition of ATX (above 50 mg/kg) resulted in significant (p < 0.05) increase in redness values in whole body and tail muscle. ATX content in shrimp tail muscle was significantly correlated with the level of dietary astaxanthin |
| Long et al. (2017) | Chinese mitten crab (Eriocheir sinensis) | ATX from H. pluvialis, esterified | 0, 29, 44, 83 | 60 | ATX tissue levels, tissue coloration | The redness (a*) of ovaries and carapace as well as the contents of total carotenoid and astaxanthin in ovaries, hepatopancreas and carapace increased significantly (p < 0.05) with increasing ATX supplementation |
| Niu et al. (2012) | Giant tiger prawn (Penaeus monodon) | ATX | 0, 100, 200 | 74 | ATX tissue retention | Dietary ATX was retained in whole body, muscle and carapace |
| Niu et al. (2014) | Giant tiger prawn (Penaeus monodon) | ATX | 0, 100 | 74 | ATX tissue retention | Apparent digestibility of ATX was high (> 90%). Tissue retention of ATX was further improved by dietary cholesterol. Astaxanthin (100 mg/kg) was better than β‐carotene (250 mg/kg) as dietary pigment, measured with the color scores (SalmonFan™) |
| Wade et al. (2015) | Giant tiger prawn (Penaeus monodon) | ATX | 0, 25, 50, 100 | 42 | Pigmentation efficacy | Dietary astaxanthin supplementation (25–100 mg/kg) can both improve pigmentation of animals exposed to black substrates, and prevent the negative effects of exposure to white substrates. Average RGB colour was used to evaluate pigmentation |
| Wade et al. (2017a) | Giant tiger prawn (Penaeus monodon) | ATX | 0, 25, 50, 100 | 42 | Pigmentation efficacy | Shrimp fed astaxanthin‐free diets had significantly reduced colour (and growth) than those fed diets supplemented with ATX. Average RGB colour was used to evaluate pigmentation |
| Wang et al. (2018b) | Juvenile kuruma shrimp (Marsupenaeus japonicus) | ATX | 0, 200, 400, 800, 1,200, 1,600 | 56 | Tissue deposition, pigmentation | The ATX content of whole shrimp increased with increasing ATX supplementation levels. The authors suggested that the optimal level of ATX for pigmentation to enhance the performance of juvenile kuruma shrimp is approximately 400 mg astaxanthin/kg diet |
| Wang et al. (2018c) | Chinese mitten crab (Eriocheir sinensis) | ATX | 0, 68 | 28 | Carapace pigmentation | The ATX was measured in the carapace of control and treated animals. The results indicated that ATX concentration was significantly higher (p < 0.05) in the treated animals and improved crab body colour |
| Yamada et al. (1990) | Prawn (Penaeus japonicas) | ATX | 0, 50, 100, 200, 400 | 56 | Tissue deposition | Total carotenoid and astaxanthin ester concentrations in tissues increased with increasing dietary astaxanthin level up to 200 mg/kg. Dietary astaxanthin was incorporated into body tissues at a higher rate than ß‐carotene or canthaxanthin |
| Zhang et al. (2013) | Pacific white shrimp (Litopenaeus vannamei) | ATX | 0, 25, 50, 75, 100, 125, 150 | 56 | ATX deposition in shell | Dietary ATX was significantly (p < 0.05) retained in the shell of Pacific white shrimp fed astaxanthin levels of 25–150 mg/kg for 56 days as compared to controls. Highest effect already reached at 50 mg/kg |