Botfly Infection

chairman

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I found a couple old threads on botflies here but I'm checking in to see if any new information is available.

For those unaware, botflies lay their eggs in a way that causes the maggots to mature under the skin of an animal. The maggot will open a breathing hole in the animal's skin, and the area around the hole will be swollen/inflamed. Some species of botfly only have one maggot per entry, others have many.

I live in northern Mississippi and the particular species of botfly I have to contend with has multiple maggots per hole. This species likes to target the cloaca of my tortoises and lay the eggs there or on the tail. I've had one botfly site up in the soft skin of a rear leg. For reference purposes, I keep K. homeana.

Last year I had one LTC female with an infection in her tail/cloaca that the vet removed 40+ maggots from. I was hoping this was an isolated incident, but this year I ended up with three different tortoises with infections. The least severe infection was my ~7" CCB female, she had about a half dozen maggots in her. One of my LTC males (had him since 2003) had about a dozen removed and hopefully he's fine now. (Per my vet, you can check for the presence of maggots by submerging the area and watching for air bubbles). My other LTC male (had him since 2002) had 80+ maggots; he's the one with the hole near his leg, his whole body cavity was full of them.

Treatment really isn't that bad. As soon as I notice an infection I give the tortoises a daily soak in water with enough betadine added so that it looks like weak tea. It keeps the area clean and the maggots don't like it, so they have a habit of making themselves easier targets for removal. I'll remove the ones I can then bring the tortoise to the vet to remove as many of the rest as possible. The vet typically has me continue betadine soaks for a while, but if it looks like all the maggots are gone then it switches to a chlorhexidine soak. My vet typically doesn't give antibiotics but she did in the case of my oldest male, as having 80+ maggots in your body cavity is a little concerning. Having one or two maggots move all the way to maturity generally isn't that bad for the tortoise, it just means that the daily soaking in betadine needs to go on for a couple months.

Previous threads have mentioned using petroleum jelly or Neosporin to seal a breathing hole but my vet said that if the approach killed maggots instead of getting them to surface then you are running the risk of sepsis. Previous threads were also dealing with one-maggot-per-hole flies, so that may make a difference as well.

I spoke to my vet about proactive treatments to prevent infections in the first place but her only suggestion was to harden the area against flies, either using mosquito netting or keeping the tortoises indoors year round. I'd obviously prefer not to do that, as my tortoises seem to like being outdoors, and they seem to like hunting the various insects that are foolish enough to enter the enclosures.

Ivermectin (which will kill botfly maggots) is not tortoise safe, and other anti parasitic treatments don't appear to work on botfly larvae (Panacur apparently won't work). It also appears that typical mite treatments aren't likely to work, nor is diatomaceous earth likely to be successful.

Is anyone aware of a preventative treatment that can be used to combat botflies?
 

Obbie

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Wow ! That is very worrisome ! I hope you are able to rid your area of those botflies ! I’d like to know how your tortoises are doing, maybe updates ?
 

Yvonne G

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Ask your vet if the external bot fly applications for horses (spray on the front legs) would be harmful for tortoises. It repels the flies off the animal
 

jaizei

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I've never dealt with bot flies, but I believe sulfur works to deter pests with humans (mosquitos, fleas, ticks, etc) so I'd give that a thought. I don't know what the dosage would be for a tortoise tho.
 

Tom

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My god. This is a horrendous story. This is the first time I've ever heard of this with tortoises. We have the single maggot type around here and it typically affects the wild rabbits or squirrels. I've never seen one on any horses, camel, kangaroo, goats, sheep, dogs or any other animal, and certainly not on any reptile. I've seen maggots the size of my thumb come out of dead cottontail rabbit. Truly inspirational for horror film writers.

Yvonne suggested fly spray. We use that to keep the biting flies off of our animals in the warmer months. That was my first thought too, but I have no idea if that would be safe to use on a tortoise? I wonder if you could spray the surrounding environment to simply repel them? If you and your vet determine it to be non-toxic, I wonder if you could just dab some on the rear of the carapace, and rinse it off before soaking them, and re-apply after a rain?
 

chairman

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I don't want to minimize the issue because the botfly infection can be bad, especially if secondary bacterial infections occur, but treatment is straight-forward and highly successful.

My female tortoise with the issue last year is my breeding female; I tried to give her the season off but she ended up laying multiple eggs this year without issues. Most weren't fertile because I didn't pair her, but still, her tail healed up very nicely. My young female with the issue this year has already completely recovered, she just has a little scar where the breathing hole used to be. My two males do not appreciate being in sterile quarantine enclosures, and they certainly aren't used to extensive daily handling, but either all the maggots have been removed and they'll heal up or the maggots will drop in a month or so and THEN they'll heal up.

I researched a couple fly treatments for horses and they appear to be Permethrin based. There are several reptile safe Permethrin products but my vet didn't seem to think they'd work well as preventatives. Given the hingebacks' love for water, a regimen including Permethrin might not be the easiest to attempt, either.

It does appear that sulfur powder would be relatively risk free, so I may try that next spring. I also have all winter to figure out how to add mosquito netting to my outdoor enclosures.
 

chairman

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Thought I'd pop in with an update. I ended up removing another 8 or so larvae from my tortoise but as of a couple days ago the holes healed shut (meaning no more larvae). He ended up with a fair amount of scar tissue around the opening in his body cavity but other than that he is fine.
 

Lyn W

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I found a couple old threads on botflies here but I'm checking in to see if any new information is available.

For those unaware, botflies lay their eggs in a way that causes the maggots to mature under the skin of an animal. The maggot will open a breathing hole in the animal's skin, and the area around the hole will be swollen/inflamed. Some species of botfly only have one maggot per entry, others have many.

I live in northern Mississippi and the particular species of botfly I have to contend with has multiple maggots per hole. This species likes to target the cloaca of my tortoises and lay the eggs there or on the tail. I've had one botfly site up in the soft skin of a rear leg. For reference purposes, I keep K. homeana.

Last year I had one LTC female with an infection in her tail/cloaca that the vet removed 40+ maggots from. I was hoping this was an isolated incident, but this year I ended up with three different tortoises with infections. The least severe infection was my ~7" CCB female, she had about a half dozen maggots in her. One of my LTC males (had him since 2003) had about a dozen removed and hopefully he's fine now. (Per my vet, you can check for the presence of maggots by submerging the area and watching for air bubbles). My other LTC male (had him since 2002) had 80+ maggots; he's the one with the hole near his leg, his whole body cavity was full of them.

Treatment really isn't that bad. As soon as I notice an infection I give the tortoises a daily soak in water with enough betadine added so that it looks like weak tea. It keeps the area clean and the maggots don't like it, so they have a habit of making themselves easier targets for removal. I'll remove the ones I can then bring the tortoise to the vet to remove as many of the rest as possible. The vet typically has me continue betadine soaks for a while, but if it looks like all the maggots are gone then it switches to a chlorhexidine soak. My vet typically doesn't give antibiotics but she did in the case of my oldest male, as having 80+ maggots in your body cavity is a little concerning. Having one or two maggots move all the way to maturity generally isn't that bad for the tortoise, it just means that the daily soaking in betadine needs to go on for a couple months.

Previous threads have mentioned using petroleum jelly or Neosporin to seal a breathing hole but my vet said that if the approach killed maggots instead of getting them to surface then you are running the risk of sepsis. Previous threads were also dealing with one-maggot-per-hole flies, so that may make a difference as well.

I spoke to my vet about proactive treatments to prevent infections in the first place but her only suggestion was to harden the area against flies, either using mosquito netting or keeping the tortoises indoors year round. I'd obviously prefer not to do that, as my tortoises seem to like being outdoors, and they seem to like hunting the various insects that are foolish enough to enter the enclosures.

Ivermectin (which will kill botfly maggots) is not tortoise safe, and other anti parasitic treatments don't appear to work on botfly larvae (Panacur apparently won't work). It also appears that typical mite treatments aren't likely to work, nor is diatomaceous earth likely to be successful.

Is anyone aware of a preventative treatment that can be used to combat botflies?
That's a lot for you and the torts to deal with but very informative to read. Thanks
 

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