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KC
12-28-2002, 05:38 PM
Here is some info I found about treating Hexamita. The information is from USF. The question I'm trying to find out does not seem to be out there. Can a Discus have regular looking feces while still having the slimy white feces or is it one or the other? I have been watching some of my infected discus and it seems that that is what is happening. Anyway, thought this info would help others.


Hexamita is a flagellated protozoan found in the gastrointestinal tracts of a variety of cold and warm water fish, including several species of Cichlids which are popular aquarium pets. It can be a serious health problem in angel fish and discus. Occasionally hexamita is found in healthy fish. Stress from malnutrition, shipping, over-crowding, or poor water quality may lead to rapid reproduction of the protozoan, resulting in disease. The genus hexamita was formerly called "Octomitus" because of eight hair-like flagella which project from the organism. Three species of hexamita have been associated with disease in fish, Hexamita salmonis , Hexamita truttae and Hexamita intestinalis . It is unknown whether these species or new species which have not yet been identified are responsible for disease in ornamental fish.


Transmission of hexamita

Hexamita is probably transmitted through the water from contaminated fecal material. The flagellated stage makes its way to the lumen of the upper intestine. There it swims freely in the intestinal and cecal fluids. The organism may be present in small numbers under normal circumstances; however, for disease to develop the organism must reproduce rapidly resulting in a massive infestation. Generation time for the flagellated form is thought to be 24 hours.


Signs of hexamitiasis

Weak or stressed fishes seem to be most susceptible to heavy infestation. Physical signs of hexamitiasis include weight loss, decreased activity and refusal of food. Angel fish which are severely infected with hexamita may lie horizontally on the surface of the water with the abdomen visibly distended. Angel fish may remain in this condition for several days. These severely infested fish often recover following treatment with metronidazole. Infestations in adult breeding angel fish may be associated with decreased hatchability of eggs or death of young fry.


Management of hexamita

Confirmation of hexamita infection is easily done by making a squash preparation of the intestine and examining it with a light microscope at 200 and 400x. The flagellates move rapidly and erratically. They are most easily seen in areas where the mucosa is broken. If the infestation is severe they are numerous and easily found.
The recommended treatment for hexamita is metronidazole (Flagyl) administered in a medicated food or, if the fish are not eating, in a bath treatment. Metronidazole can be administered orally at a dosage of 50 mg/kg body weight (or 10 mg/gm food) for 5 consecutive days. A recipe for a gelatinized food is shown in Table 1 . The medication can also be mixed with dry food using fish oil as a binding agent. One teaspoon of metronidazole weighs approximately 2.25 gm; therefore 2 tsp. should be added to each pound of food. The drug should be added when the gelatinized mixture has cooled, but has not yet set. The medicated food can then be frozen for storage. During the 5 day treatment regime feed only the medicated food to the fish. If fish are not accustomed to a gelatinized food they can be trained to accept the mixture by preparing the food without medication and feeding it occasionally. Training should be done when fish are healthy rather than waiting until they are sick. Sick fish do not eat well and may completely refuse unfamiliar food.

If fish are already sick and off-feed metronidazole can be administered in a bath at a concentration of 5 mg/l (18.9 mg/gallon) every other day for three treatments. This treatment is effective but may not clear the organism from the fishes' intestinal tract as well as the medicated food.

Since hexamita can be kept alive in laboratory media, it is assumed that it is an inhabitant of aquaria where organic material has been allowed to accumulate. Cleaning of gravel and filter materials will assist in eliminating the organism from the environment. It may be advisable to periodically check broodstock for subclinical hexamita infections. Even though the fish may not be sick, low levels of the parasite may have an adverse effect on reproductive performance or may flare up under conditions of stress. These subclinical infections can be easily treated with a medicated feed before real problems develop.


Summary

Hexamita is a flagellated protozoan that can be found in the intestine of healthy and sick fish. It is of particular importance in angel fish and discus. It can also cause problems in oscars and African cichlids, and other fish. Stress, particularly caused by poor water quality or inadequate nutrition, seems to be associated with increases in the number of flagellates in the gut and development of clinical disease. Elimination of stress and correction of husbandry will help correct an outbreak of hexamitiasis. Metronidazole provided as a medicated feed or a bath is an effective treatment and even severely affected fish often respond to therapy. Commercial producers of ornamental cichlids should periodically check fish for hexamita infections and treat any infected fish.



Recipe for gelatinized food which can be used to deliver oral medication to ornamental fish.

Ingredients:

6 oz
Can of shrimp

2 oz
Frozen spinach

1 oz
Grated carrots

3 tbsp
Baby cereal (dry)

2 tbsp
Brewer's yeast

2 oz
Unflavored gelatin

15 oz
Water

Optional ingredient:

1 tsp
Liquid vitamins

Procedure:

1.Blend 5 oz of water with shrimp, spinach, carrots, baby cereal, brewer's yeast and vitamins.

2.Boil remaining 10 oz of water.

3.Add boiling water to gelatin in a bowl.

4.Cool until gelatin mixture is hot but doesn't burn.

5.Add contents of blender to partially cooled gelatin mixture, mix thoroughly.

6.Add medication to cooled mixture.

7.Pour into flat pan and refrigerate.

8.Cut gelatinized mixture into cubes for feeding and store in freezer.





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KC
12-28-2002, 05:46 PM
Here is other info I found on treatment...

Other Treatment
The antibiotic metronidazole (chemically labeled [2-methyl-5-nitro- 1-imidazoleethanol] and synonymous with "Flagyl," the trade name for this benzimidazole derivative and antitrichomonad for the treatment of human reproductive and urinary tract flagellated protozoan infections (frequently of the genus Trichomonas, i.e. T vaginalis, among others) is very effective at a rate of 20 milligrams per gallon of water, added weekly for a period of three weeks. Monitor water quality for measurable levels of dissolved nitrite (NO2-) during treatment. Remove carbon from filters, if used. Fifty-percent of tank water should be changed before each treatment.

Be certain to replace the amount of metronidazole removed when performing more frequent water changes. In severe infestations, 250mg metronidazole per 10 gallons of water every other day for four days, with at least 50% water changes prior to each treatment, may be more effective. Still more effective is daily dosing of 250mg metronidazole per 10 gallons of water for five days, with water changes before each treatment. Metronidazole may be removed from the water column via carbon and/or water changes.

Another treatment method is as follows: perform a 50% water change followed by a dose of 500mg metronidazole per 10 gallons of water. Change no water until the third day, when a 50% water change is performed followed by a dose of 250mg per 10 gallons of water. Repeat this 250mg dosage and water change regimen on the fifth, seventh, and ninth days. It is a ten day treatment. The reasoning behind this method is to hit the protozoan hard with the first dosage, and to finish it off with the remainder of the treatment.

When treating discus in conjunction with metronidazole, elevate water temperature to approximately 92ºF. This will increase the effectiveness of metronidazole, a "design drug" that works best at a temperature of 98.6ºF as it was originally intended for use with humans (do not elevate water temperature to this degree). It may also help to bolster the fishes' immune system and should weaken Hexamita, leaving it more susceptible to treatment. This should not be done If other species of fish intolerant of this high temperature are kept with discus.

If fishes are still consuming food it is advisable to pre-dose food with metronidazole as well. 100mg per tablespoon of food is an ideal starting point. Flake food may be moistened, measured, and mixed with the medicine, then frozen and fed in small servings; this method may be applied to other frozen foods, i.e. beefheart based preparations. Feed medicated food for at least seven days. During this time, feed no other foods. Take care to ensure that food is consumed immediately following introduction into tank water, so that as much of the medicament is consumed as possible. Allow frozen foods to thaw before feeding.

brewmaster15
12-28-2002, 10:28 PM
Hi KC,
Thanks for the info, but can you tell me exactly where it came from? I want to be sure that we have permission to post it here.

thanks,
al

KC
12-29-2002, 09:57 AM
http://edis.ifas.ufl.edu/VM053

Copyright Information

This document is copyrighted by the University of Florida, Institute of Food and Agricultural Sciences (UF/IFAS) for the people of the State of Florida (I live in Florida). UF/IFAS retains all rights under all conventions, but permits free reproduction by all agents and offices of the Cooperative Extension Service and the people of the State of Florida. Permission is granted to others to use these materials in part or in full for educational purposes, provided that full credit is given to the UF/IFAS, citing the publication, its source, and date of publication.

brewmaster15
12-29-2002, 10:39 PM
Thanks KC,
I thought it looked familiar. Simply has been in contact with UF/IFAS and has previously obtained permission to post all of their articles here. Just wanted to check and be sure. There have been some complaints from others in the past.

Thanks again for sharing,
al

ps...

Can a Discus have regular looking feces while still having the slimy white feces or is it one or the other? I have been watching some of my infected discus and it seems that that is what is happening..

yes... often times it may indicate the fish is fighting off the infection....


you may be interested in this article from our library...

http://forum.simplydiscus.com//index.php?board=10;action=display;threadid=1058


hth, al

jim_shedden
12-31-2002, 08:44 AM
Thanks : good info

JIm