LOLS10在线直播下注

sunbet手机app版Shape 宝盈真钱平台Shape 网上兼职彩票注册author 牛牛手机版Shape 老虎机怎么压会赢chevron bo博电竞下载cross 金博体育appShape 龙虎1248打法Shape 巴登彩票代理Shape 一分赛车appGroup 网上炸金花hamburger 万博体彩apphome 世界俱乐部杯Group 皇冠足彩平台magnify 金蟾千炮捕鱼Shape 十博bet体育投注Shape 万博体育appShape 彩票66软件rss 生死门8个口诀Shape

Oyster Herpes Virus (OsHV-1)

What Is It?

Oyster herpesvirus is a virulent viral disease of the Pacific oyster Crassostrea gigas (also known as the rock or cupped oyster). This is the only species of shellfish that is currently known to be susceptible to this virus.

The disease is temperature dependent only occurring when water temperatures exceed 16C. The highest mortalities occur in juvenile oysters, however all life stages are thought to be susceptible to infection.

Adult mortality varies between 10 - 30 per cent, however juvenile mortality is a lot higher, between 60 - 100 per cent.

The cause of the virus is still unknown, although it has been suggested that there are a number of causative agents. One of these is varying climates and temperatures. A French scientist, Tristan Renault, from the genetics and pathology lab at the IFREMER (French Research Institute for Exploitation of the Sea), has suggested in recent publications that one of the contributing factors to the appearance of the disease could be global warming and a subsequent significant rise in the oceans temperature.

Where and When Might it Occur?

Oyster herpesvirus has been found in many parts of the world including the LOLS10在线直播下注A, Europe, Japan and China where it occasionally causes a condition in Pacific oysters called summer mortality.

However a new variant of oyster herpesvirus (OsHV-1 var) associated with very high levels of mortality was recognised in France causing exceptional mortality events in Pacific oysters in 2008 and 2009.

This disease has spread throughout the major oyster growing areas in France, including both the Atlantic and Mediterranean coasts, and has also occurred in Jersey and in parts of Ireland.

In 2010 the UK experienced the first outbreak of oyster herpesvirus at a shellfish farm in Whitstable, Kent.

Diagnosis

LOLS10在线直播下注High levels of mortality usually occurs in in water temperatures exceeding 16C (60.8F).

Control/Treatment

The most efficient method to prevent the spread of the disease is too minimise the movement of stock. However this is not always successful. In Whitstable, South England, a closed farming system was in place, however oysters were still found to be infected with the virus.

Producers are advised not to re-water any oysters from infected areas.

There is no cure currently available.

Source: Defra