Lumpy skin disease (LSD) is a highly infectious disease of cattle caused by a virus belonging to the Capripoxvirus genus of the family Poxviridae. The purpose of this study is to place on record the first confirmation of LSD in the Sultanate. The disease was diagnosed and confirmed using polymerase chain reaction, histopathology, transmission electron microscopy and serum neutralization testing. The epizootic occurred in 2009 involving a large number of animals and covering a wide area including Nezwa, Alqabel, Sohar, Saham and Burimi. Morbidity and mortality rates of 29.7 and 26.3 %, and 13.6 and 15.4 % were observed at Nezwa and Sohar, respectively. The clinical signs were much more severe in Holstein–Friesian cattle compared to indigenous breeds and were characterized by multiple skin nodules covering the neck, back, perineum, tail, limbs and genital organs. Affected animals also exhibited lameness, emaciation and cessation of milk production. Oedema of limbs and brisket, and superficial lymph node enlargement were highly prominent. It is not known from where the virus originated, or how it spread to the Sultanate. The disease has become endemic in the country and is liable to extend to other Gulf Cooperation Council Countries and cause a pandemic. It is of major concern to the Omani dairy industry. Due to the widespread presence of screw worm, serious economic losses can follow outbreaks.

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An outbreak of chlamydiosis was diagnosed in hatchling and juvenile Indopacific crocodiles (<em>Crocodylus porosus</em>) on a crocodile farm in Papua New Guinea. The outbreak was characterised by high mortality with hepatitis and exudative conjunctivitis. The agent appears to have been introduced with live wild-caught crocodiles, which are purchased routinely by the farm. Improved quarantine procedures and treatment with tetracycline led to a rapid reduction of losses on the farm

The heads of nine 2.5 to 3-year-old Nile crocodiles (Crocodylus niloticus) were obtained from a commercial farm where crocodiles are raised for their skins and meat. The animals from which these specimens originated were clinically healthy at the time they were slaughtered. A detailed description of the macroscopic and microscopic features of the palate and gingivae of the Nile crocodile is presented and the results are compared with published information on this species and other Crocodylia. The histological features are supplemented by information supplied by scanning electron microscopy. Macroscopic features of interest are the small conical process situated at the base of the first two incisors of the maxilla, the distribution of cobbled units on the palate, and the broad dentary shelf forming the rostral aspect of the mandible. Histologically the palate and gingivae did not differ significantly from each other and both regions showed a presence of Pacinian-type corpuscles. Two types of sensory structures (taste receptors and pressure receptors) were identified in the regions examined, both involving modification of the epithelium and the underlying connective tissue.

Mononuclear cells were isolated from the peripheral blood of a buffalo infected with a Theileria sp. using density gradient centrifugation, and the cells were put into culture flasks covered by a monolayer of bovine endothelial cells. Twenty days after culture initiation, cells containing macroschizonts were detected in Giemsa-stained smears. The first subculture was carried out on day 45 of culture propagation. Subsequently, infected cells were subcultured twice a week, and each time 1 to 2 x 10(6) per milliliter cells were harvested. DNA was extracted from culture material and a partial polymerase chain reaction amplification of the 18S ribosomal RNA (rRNA) gene was carried out using Theileria genus-specific primers. Sequence data and phylogenetic analysis using the 18S rRNA gene indicated a close relationship to Theileria sp. buffalo, previously described in literature. Here, the first successful attempt to establish a macroschizont-infected lymphoblastoid cell line of Theileria sp. (buffalo) from an African buffalo is described.

A field outbreak of pox virus infection in juvenile Nile crocodiles (Crocodylus niloticus), in which high morbidity and negligible mortality occurred, is described. Histopathological examination of the skin lesions revealed numerous large intracytoplasmic inclusions in the dermis and a very mild dermal inflammatory reaction. Scanning electron microscopical examination of the skin revealed the presence of large numbers of virus particles in the inclusions. Skin lesions persisted for 5 to 6 months.

As a means to develop African horse sickness (AHS) vaccines that are safe and DIVA compliant, we investigated the synthesis of empty African horse sickness virus (AHSV) particles. The emphasis of this study was on the assembly of the major viral core (VP3 and VP7) and outer capsid proteins (VP2 and VP5) into architecturally complex, heteromultimeric nanosized particles. The production of fully assembled corelike particles (CLPs) was accomplished in vivo by baculovirus-mediated co-synthesis of VP3 and VP7. The two different outer capsid proteins were capable of associating independently of each other with preformed cores to yield partial virus-like particles (VLPs). Complete VLPs were synthesized, albeit with a low yield. Crystalline formation of AHSV VP7 trimers is thought to impede high-level CLP production. Consequently, we engineered and co-synthesized VP3 with a more hydrophilic mutant VP7, resulting in an increase in the turnover of CLPs.

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