Matthew King
Crustacean parasities (anchor worm/gill worm) can be seen as worms up to 20mm long (sometimes white in colour). These parasities are often caused through poor water quality. As the shells of crabs are hard they rarely manage to penetrate the crabs shell and cause intestinal damage but for the water quality to be that poor may result in other diseases that will make your crab very poorly. The way around this is to change the water. (If you have a lot of water in your tank only 20% water change otherwise it will damage the crab having such a drastic change in water. In fish they can be treated with anti-crustacean parasite treatment, however crabs are sensitive to chemicals so I would do 3/4 water changes over the next month before trying such treatment.
The information on below may come from several websites, all of which have been credited...
From blue crab website...
"Pepper Spot" Disease
The meat of an infected crab appears to be peppered with small dark spots which indicate that it is infected with parasites (called buckshot or pepper crabs by some watermen). Although its appearance may be unappetizing, the cooking process kills the parasites and renders the crab meat completely safe to eat.
More scientifically, the crab contains the microphallid fluke (Microphallus basodactlyophallus) which has been hyperparasitized by a haplosporidan protozoan (Urosporidium crescens). The minute, brownish, protozoan infects the tissues of the encysted worm and undergoes extensive multiplication until the cyst increases in size by many times and the worm's tissue has been replaced by spores. The vast number of spores in a cyst distinguishes each cyst as a visible black speck.
The disease is spread by any of four species of snails which are found in shallow low-salinity estuaries. The infected snails release the infective free-swimming larva (cercaria) which penetrate the crab. Many crabs are infected with the fluke which can barely be seen without a microscope. It isn't until the fluke itself becomes infected with the protozoan hyperparasite, becoming visible, that people exhibit apprehension. (Jeff Shields, VIMS).
Design and content D. Warren
|
|
