Reptile & Amphibian Forums

We have multiple American bullfrogs that keep developing lesions. Directly following their arrival from Carolina Bio Lab Supply in September, their feet became swollen and red so we began dosing the water with 26.6ml of stress coat every water change (twice a week). Their feet got better but then in December, they developed lesions on their legs and back, which start as what look like black blisters or slight discolorations. The bullfrogs were housed with a wild caught leopard frog that died and may have brought something into the system. We have tried a number of treatments recommended to us by our veterinarian including: food injected 0.1mL Enrofloxacin (5mg/mL) for about 2 weeks in conjunction with topical silvadene to wounds, 0.07mL Enrofloxacin (22.7mg/mL concentration) applied transdermally to their back (never on top of wounds) for 2 weeks. Neither treatment seemed to improve the wounds and silvadene actually seemed to irritate it more because of the application process.

They are housed in a 250 gallon aquarium with about 50 gallons of water (in aquarium and sump). Ambient air temperature is 75-80*F, humidity 80-88%, water temperature 72-75*F, pH 8.8-8.9, ammonia 0, and nitrite 0.01-0.02mg/mL. There are 3 Repti-glo 5.0 UVB bulbs, 3 Repti-glo 2.0 UVB bulbs, and 2 Repti-glo 25 watt heat bulbs mounted 20” above the frogs with plexiglass below them. The exhibit was created using a layer of bricks on the bottom, a layer of pea gravel, then a layer of freshwater Eco-Complete Planted Aquarium Substrate. There are three long planters with drain holes in the bottom, a layer of pea gravel, a layer of Eco-Complete, and then a layer of Organic Soil (we planned to have live plants but they didn’t work out). The decorative rock is flagstone. We have a sock filter, blue pre-filter, bioballs, and a pump sponge to help filtration. There is also a rain-bar made from irrigation dripline. Both of these pumps are sitting directly in the sump. We use tapwater that is run through a mechanical pleated filter, and then a carbon filter to fill the tank after water changes. Two TetraFauna ReptoGuard Sulfa-Blocks are placed in the sump about once a month (they advertise they last 45-60 days however they disintegrate a lot quicker in our tank).

Attached are photos of the aquarium and the frogs. The password for photos is "bullfrog". Any ideas on what could be causing this would be greatly appreciated!!

Photos of Bullfrogs & Exhibit

If the issue is a pathogen that the WC Leopard Frog brought to the bull frogs, most spreading infections are going to be viral or bacterial. If it is viral there is not much that can be done except to hope the bullfrogs have a healthy and functional immune system.

If it is bacterial then you can fix it but it will be a pain. If the bacteria was treated for but then came back it is probably because it is now living in the enclosure. If this is the case, a complete cleaning and sterilization of the enclosure and all the parts MIGHT be required depending on the bacterium species. This can be costly, time consuming, or both. After words care must be taken to avoid chemical contamination from whatever was used to sterilize the enclosure.

The last possibility that immediately comes to my mind is that the Carolina Biological Supply Lab's population might have an internal contaminant but I highly doubt that. Always worth a check though, heck you might be the ones that brings it to their attention before there is a wide-spread issue. Again though, they are rather on top of what they are doing over there.

My belief, and most likely result, is something be it a deadly anuran virus or a bacteria, or even a parasite, came in with the Leopard Frog. I catch amphibians to breed, release, and raise the tadpoles all the time for my 2 Heterodon platirhinos. Occasionally I will get a Bronze/Green Frog or Toad with some unknown contaminant that if left alone, 2 times out of 3, spreads to the other amphibians in the enclosure.

Also, the password to see the pictures appears to not work. Unless the quotation marks are part of what I type in, just bullfrog does not work.

Good luck with them and hopefully the issue with the frogs can be resolved.