EFFECTS OF ASTAXANTHIN DEPOSIT ON Penaeus vannamei WHEN FED NATURAL XANTHOPHYLL

Under  intensive  commercial  shrimp-culture,  abnormal body color  happens frequently  because lack  of  carotenoid food  sources. Natural xanthophyll  (extracted from marigold) is a natural pigment  obtained from marigold  flowers,  and its main  pigment components are lutein and  zeaxanthin. The long-term application practices in animal feed have verified its safety and effectiveness. Studies have shown  that  adding  natural  xanthophyll  in  shrimp  feed can  effectively enhance shrimp  body color. In comparision with astaxanthin, natural xanthophyll is relatively inexpensive, also its safety has been affirmed.  There  has a  great  potential for its application in  shrimp  feed.  The  present  study was  conducted to test the pigmentation  efficiency  of  Leader Golden  5% (natural  xanthophyll  product) adding to feed of Penae us  vannamei,  and to compare astaxanthin product.

An 8-week  feeding trial  was  conducted  in  an indoor  shrimp-culture system  in   Hainan   prov ince  of China. The shrimp  is juvenile Penaeus  vannamei with  initial mean weight of 0.29 g.  Indi vidual  units  were  contained   within   fiberglass tanks  with  a density of  40 shrimp  per tank.  Each  tank is independent  and  has the  same  size  of 500 L. Water quality  was operated well during  the  trial by daily  exchange, water  temperature  was  23-26  °  C , salinity was 33-35  %  , dissolved  oxygen  was 6-7 ppm, pH  was  8-8.2 ppm, ammo nia  was  below 0.1 ppm, nitrite  was  below 0.01 ppm.  The  goal  of  this  study was  to  examine  the  effects of  astaxanthin deposit on juvenile Penaeus  vannamei when  fed tl1ree practical diets with or without natural xanthophyll and astaxanthin.

Other practical ingredients included fish meal, soybean meal, peanut meal, wheat flour, vitamin and mineral premix, etc (Table 1).

After 8 weeks trial , Penaeus vannamei fed a practical diet with xanthophyll (Diet 2) or astaxanthin(Diet 3) had  significantly (P  < 0.05) higher final body astaxanthin content when compared to the control group (Table 2). In additi on, th ere is  no  significant  differences between the two  experiment group. The results indicate that natural xanthophyll can efficiently convert into astaxanthin by Penaeus vann amei  itself and  deposit  on its body.