Effect of dietary pigment on growth performance and disease resistance in black tiger shrimp post larva (Penaeus monodon, Fabricius)

Effects of dietary pigment on survival and disease (white spot syndrome virus: WSSV) resistance in black tiger shrimp post larva (Penaeus monodon, Fabricius) (PL15) for a 30-day period were studied. The results showed that not only was mean survival of black tiger shrimp (PL15) fed with supplementation of Lucarotene or Betatene at 125 mg/kg diet significantly higher (P<0.05) but also the body color was increased. There were no effects of dietary pigment on mean weight, percent weight gain and WSSV resistance. However, mean WSSV resistance of black tiger shrimp (PL15) fed diet containing Lucantin pink 50 mg/kg diet, Spirulina 30 g/kg diet or Betatene 125 mg/kg diet was higher than that of control

The application of fluorescence in situ hybridization (FISH) technique for studying the microbial communities in intestinal tissues of white shrimp (Penaeus vannamei)

Fluorescence in situ hybridization technique is very useful for the evaluation of microbial communities in various environments. It is possible to apply this technique to study the intestinal microflora in white shrimp (Penaeus vannamei). Different fixatives and storage temperature were tested in this technique. It was found that fixation with 10% buffered formalin for 12 hours and changed to 70% ethanol shown positive results when compared to the fixation with Davidson's fixative or RF fixative. The best signaling was obtainedfrom the samples which were stored in -20ºC. By using the DNA probe targeted to the Eubacteria domain (EUB338 probe, 5′-GCT GCC TCC CGT AGG AGT-3′) labeled with fluorescein as a hybridizing probe, it was found that most intestinal microflora were aggregated with the intestinal contents, or dispersed in the lumen. There was not evidence of the attachment of the microflora with the intestinal epithelium in this study

Effects of carotenoid sources on growth performance, blood parameters, disease resistance and stress tolerance in black tiger shrimp (Penaeus monodon Fabricius)

Two feeding trial were conducted to determine the effects of various sources of carotenoid on growth performance, disease resistance, blood parameters, stress tolerance and pigmentation in juvenile black tiger shrimp (Penaeus monodon). Trial I was performed in small shrimp (1 g average body weight). The shrimp were fed with control diet without carotenoid (diet 1) while diets 2 to 6 contained 50 mg/kg astaxanthin (Lucanthin Pink®), 125 mg/kg β-carotene (Lucarotin®), 200 mg/kg β-carotene (Lucarotin®), 125 mg/kg Betatene® extracted from Dunaliella and 3% dried Spirulina respectively. There was an improvement in color in all groups of shrimp fed caroteniod supplemented diets, but no significant differences in weight gain or survival among the shrimps fed each test diet (p>0.05). Resistance to white spot syndrome virus (WSSV) infection and stress tolerance (salinity stress), were not significantly different among treatments. Trial II was performed in juvenile shrimp (10 g average body weight) fed test diets containing 100 ppm astaxanthin (Lucanthin pink®), 125 mg/kg β-carotene (Lucarotin®), 250 mg/kg β-carotene (Lucarotin®), 250 mg/kg Betatene® and 3% dried Spirulina compared with those fed control diet without carotenoid. At the end of 6 weeks feeding period, shrimp fed control diet as well as astaxanthin and dried Spirulina supplemented diets had higher levels of total hemocyte counts than those of all β-carotene supplemented diets feeding group. However, phenoloxidase activity and clearance of pathogenic vibrio from the hemolymphwere not significantly different among the treatments (p>0.05). Astaxanthin levels were highest in the shrimp fed all carotenoid-supplemented diets. In conclusion, a natural carotenoid i.e. dried Spirulina and carotenoid extracted from Dunaliella which have a lower production cost than analytical carotenoid showed beneficial effects on shrimp feed supplement