KHV (Koi Herpes Virus) Diagnostics

The infection shows up at various times during infection. The virus might be noticeable in the gills or blood for just a couple of hrs or days. In the liver and especially the kidney, contaminated fish will typically have detectable infection.

So, not all cells kinds are “equal” diagnostically.

Best: Produce and homogenize kidney and liver. Ship frozen or near freezing for PCR. Formalin repair for Sitting Hybridization.

Handling Tissues

Long-dead (rotting) fish will certainly not work as the DNA stability can be jeopardized.

You should utilize real-time fish or EXTREMELY just recently dead fish for ideal results and use kidney, liver and gill.

PCR test tries to find particular DNA pens which are normally present in dead and perishing fish organs. Can be iced up.

Live infection will not be recoverable from icy samplings.

Gill “swabs” are just about pointless unless there is overt (apparent) disease amongst fish being tested.

Tests to Run

For now, the very best type to locate infection is a PCR examination.

PCR = Polymerase chain reaction examination. It identifies a precise sequence of unique nucleic acids only located in the Koi Herpes Virus.

Sitting Hybridization– Trying to find infection in the cells. (Showing infection).

There is also an agglutination (antibody) test for fish blood which would certainly show past infection, and assist display real-time fish.

Sitting Hybridization.

Operate on Tissues Seeking Carriers.

Detects infection DNA really IN the cells, which is a lot more specific and delicate compared to the PCR examination and the fish don’t have to be infected or passing away. Yet they probably need to die for example collection.

Tissues are prepped for histopathology, are stained with a noticeable healthy protein which expecteds specific viral KHV DNA, then the protein/DNA complex turns up blue under the microscopic lense.

This examination is offered at UGA and is good for virus spotting “carriers”.

Serological Assay.

This examination uses blood so the fish do not need to perish.

They’re presenting a marked KHV infection bit which triggers antibodies in the blood to agglutinate.

If the blood proteins agglutinate, it implies the fish has antibodies, and this suggests the fish was, in the last 8 months, affected.

Antibody “memory” to KHV appears only to last 6-8 months.

This is a good life saving test to say to if a fish was ever before affected with KHV.

Do the examinations “Play” together?

PCR searches for the infection LIVING in cells. Generally this virus test can not be relied upon to show provider states.

Sitting Hybridization searches for virus “HIDING” in the tissues and is far more delicate, equally as specific, and great for locating providers.

The Serology test confirms a fish made it through an infection. It doesn’t determine providers. It helps when used WITH sitting hybridization–.

To wit: If the serology shows ‘infection survivor’ then the in situ hybridization examination comes to be colossally essential to assist establish latency or service provider state.

In situ hybridization on a fish negative by serology is of far less worth. Why?

Due to the fact that if the fish is adverse on serology it would suggest it’s never been exposed or contaminated … So the second examination seeking virus PARTICLES is irrelevent.

KHV (Koi Herpes Virus) Diagnostics