Hepatopancreatic Microsporidiosis (HPM) or Enterocytozoon Hepatopenaei (EHP) Vannamei Aquaculture
Enterocytozoon Hepatopenaei (EHP) is a microsporidia disease that first occurred in P. monodon tiger shrimp in Malaysia in 1989. EHP can spread directly through cannibalism but does not trigger White Feces Syndrome (WFS), EHP can also be found in shrimp infected with WFS. Chances are EHP is a trigger factor for WFS. EHP transmission can also be through Polychaeta and mollusks (mollusks) but it is not yet known whether they can act as carriers or not. Crabs can also be a source of transmission for shrimp. Transmission of EHP does not require hosts. Until now the prevalence of EHP is unknown. Studies from the Central Institute of Brackishwater Aquaculture (CIBA) indicate the incidence of EHP around 15.6% of 100 farmers. Around 16% of them were detected as having slowed growth and 50% were experiencing WFS. Mortality caused by EHP is quite varied, reports from farmers show 1-2% of daily mortality.
This parasitic EHP infection is also widely associated with White Feces Syndrome (WFD-White Feces Disease). Shrimp infected with EHP will be blackened and small in size. This parasite infects hepatopancreas tubular epithelial cells from shrimp connective tissue. Then limit the number of nutrients that can be absorbed by the hepatopancreas. As a result, shrimp become starved so that slowing growth occurs.
The microscopic picture that is seen is a change in color like milk in the muscles due to microsporidia collection. Therefore this disease is also called "cotton shrimp disease" or cotton shrimp disease.
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| EHP Virus |
virus prevention methods
Prevention of EHP at the stage of seeding and enlargement is to not use live animals (Polychaeta and mollusks) as food. Whereas for ponds, the following two things can be done to control EHP: First, use seeds that are free from EHP. Second, pond preparation is good, especially in ponds that have experienced EHP, EHP spores have thick walls and are not easily activated even by using chlorine in high doses. In ponds that are still based on land, they can use CaO during the period of re-preparation of pond land. Because EHP is a parasite that forms spores, water disinfection can be an important consideration in preparation for ponds that have never experienced EHP.
