Histology and ultrastructure reveal a new granulosis-like virus in Penaeus monodon affected by yellow-head disease

Abstract

A recently repor1t.d dlsease s y n d~o m e of Penaeus monodon In Thalland IS called 'yellow-head' or hua leung In Thal It is usually charactenzed by llght yellow coloratlon of the dorsal cephalothorax area and generally pale or bleached appearance of a f f~c t e d prawns The yellow color In the cephalothorav reglon iesults from the underlying y e l l o~~ hepatopancreas showlng through the translucent carapace In m o~i b u n d shrimp In h~stological prepdrations of moribund yellow-head specimens for the light mlcloscope. no consistent bacteiial fungal or parasltlc agents could be found The lylnphold organs ot yellow-head specimens sho\ved extensive abnormalities These Included obv~ously necrotlc cells and vacuolated cells with hypertrophied nuciel Also evldent were vely densely basophil~c, globose cytoplasmic ~nclusions located adjacent to some ot the hypertroph~ed nuclei Slrn~lar basophil~c inclusions were found In interst~tl~il hepatopancreat~c tissue In connective tlssue u n d e~ lylng the mld gut, In cardlac tissue, In glll t~s s u e and In hematopoetlc tissue T l a n s m~s s~o n electron mlclographs revealed the presence of pic\iously undescrlbed rod-shaped, enveloped virions in the cytoplasm adjacent to the nuclei of cells f~ om various tissues Free vlnons \yere also present In intercellular spaces The virions were s~r n d a to those of the ~tlsect grahulosls vlruses (Baculov~r~dae) In terms of cytoplasmic locatlon size, morphology and development. However, they were not occluded by granulln

Duplex real-time PCR for detection and quantification of monodon baculovirus (MBV) and hepatopancreatic parvovirus (HPV) in Penaeus monodon

“…These viruses have the same target tissues, infecting the hepatopancreatic and midgut epithelial cells of penaeid shrimps (Lightner & Redman 1981, Chong & Loh 1984, and co-infected Penaeus monodon are often found in SE Asia (Chantanachookin et al 1993, Flegel et al 1999, Manivannan et al 2002. Outbreaks of these viruses can be devastating to aquaculture production, as infections of larval to early juvenile stages can result in 90 to 100% mortality (Lightner & Redman 1985, Lightner 1996.…”

Multifactorial interaction of growth factors on Penaeus monodon lymphoid cells and the impact of IGFs in DNA synthesis and metabolic activity in vitro

“…Conceiving the above, application of growth factors has been considered as a promising strategy and in this process the lymphoid cell culture has been chosen owing to its importance in developing shrimp cell lines . Importance of lymphoid cell culture resides in the fact that lymphoid organ is a prime target and the site of replication of most systemic viruses (Rusaini and Owens 2010), such as, Lymphoidal parvo like-virus (Owens et al 1991), Spawner-isolated mortality virus (Fraser and Owens 1996), White spot syndrome virus (Wang et al 2000;Rodríguez et al 2003), Yellow head virus (Chantanachookin et al 1993), Lymphoid organ virus (Spann et al 1995), Taura syndrome virus (Hasson et al 1999), Infectious myonecrosis virus (Tang et al 2005), Mourilyan virus (Rajendran et al 2006), Laem-Singh virus (Sritunyalucksana et al 2006), Rhabdovirus of penaeid shrimp (Nadala et al 1992), and Lymphoid organ vacuolization virus (Bonami et al 1992). Lymphoid cell culture has been demonstrated as a platform for viral shrimp studies (Jose et al 2012).…”

Immunological-based assays for specific detection of shrimp viruses

“…YHV first emerged in farmed black tiger shrimp (P. monodon) in Thailand in 1990 [47] and caused a loss of shrimp production equivalent to 30-40 million USD [48] . The entire crop is typically lost within a few days after the appearance of the gross signs of this disease [49] . YHV is a bacilliform, enveloped, (+) single-stranded RNA virus classified in the new virus genus Okavirus, the new family Roniviridae and the order Nidovirales [50][51][52] .…”