Melanosis is a major problem associated with the quality loss of Pacific white shrimp. This is mediated by polyphenoloxidase (PPO), in which biochemical and molecular properties can be varied with species, molting period, etc. The better understanding of PPO characteristics should pave a way for lowering melanosis, thereby extending the shelf life of Pacific white shrimp during handling and sto...

Lysozyme, an antibacterial protein, has been implicated in innate immunity in invertebrates, but its activity in shrimp remained to be determined. We cloned the white shrimp lysozyme cDNA using a PCR strategy and detected its activity in haemocytes using a lytic-zone assay against Micrococcus luteus. The cloning was based on a reported EST (dbEST BE18831). The deduced amino acid sequence result...

In this study, effect of different levels of dietary protein (25, 35 and 45 per cent) and water salinity (0-3, 12-15 and 32-35 ppt) on antioxidant enzymes of white leg shrimp (Penaeus vannamei) was studied. 324 P.vannamei (with mean weight±SE: 5.55 ± 0.18 gr) were randomly distributed in twenty seven tanks. Experimental shrimps were fed by formulated diets for 56 days and at the end of the expe...

Structural changes in Midwest agriculture over the past two decades have resulted in a number of empty and unused farm buildings. Farmers therefore have been exploring alternative uses of livestock farm buildings for the production of other cash crops, including aquaculture products. In Indiana, Pacific White shrimp (Litopenaeus vannamei) production has attracted interest, and a number of small...

Cultured shrimp are often exposed to different toxic products during rearing practices that may affect survival and quality of the product. An evaluation of the effects of paralytic shellfish toxins (PSP) from species of Gymnodinium catenatum in white leg shrimp (Litopenaeus vannamei) has been carried out in this study. Death was observed at doses > 5.0 MU (equivalent to 1.1 mug/g of STX), whil...

A series of experiments using serological reagents was conducted to examine predation, ingestion and digestion in a model predator-prey system. The harpacticoid copepod Amphiascoides atopus, obtained from mass culture, was used as prey and the grass shrimp, Palaemonetes pugio, as predator. Bulk-gut passage time in P. pugio was measured by visualization of latex beads and ranged from 0.5 to 4 h ...

During viral infection in vertebrates, cytokines play important roles in the host defense against the virus. However, the function of cytokines in invertebrates has not been well characterized. In this study, shrimp cytokines involved in viral infection were screened using a cytokine antibody microarray. The results showed that three cytokines, the Fas receptor (Fas), platelet factor 4 (PF4) an...

Two epizootics of cultured shrimp occurred in India in 1994. The first case of mass mortalities of tiger shrimp Penaeus monodon in July 1994 was very similar to that caused by yellowhead virus (YHV) infection with regard to gross clinical signs, host species and size of shrimp affected, but it was histologically atypical. Very interestingly, intranuclear inclusions typical of a white spot syndr...

BACKGROUND Recent work suggested that the presence of specific memory or some form of adaptive immunity occurs in insects and shrimp. Hypervariable pattern recognition molecules, known as Down syndrome cell adhesion molecules, are able to mount specific recognition, and immune priming in invertebrates. In the present study, we attempted to understand the immune response pattern of white shrimp ...