Massive rat die off - No idea what the cause is.

[Anatopism]

As of a few days ago, we've been losing adult rats left and right. The babies seem fine. Rats will seem perfectly healthy, then within a matter of hours start showing signs of physical sress, and are dead anywhere from a couple hours to a day later. I pulled out 4 dead adults this morning. 3 two days ago. 6 a day before that.

It's making me believe it may be disease/illness, as nothing has changed (except for a mixture of straw with their normal bedding in one rack, but the issue spans over all racks, and straw was replaced back to pine more than a week ago).
- I'm having 1 baby die to every 4-6 adults
- Each rack has it's own watering system: 2 have a gravity feed/valve system, the big-tub rack has water bottles for the time being.
- The Norways are the ones dropping, the ASFs al seem healthy and lively, no deaths.
- It's been in the 50-70 degree range the last week (moreso on the colder end) and on the warmer days I've cracked the garage door open, and it has not been too warm for them.
- We have chickens and ducks also in the garage, on the same bedding (pine), drinking the same water, showing no illness.
- We rotate in new blood every few weeks, but none have been added to the colony recently.
- We have fed off some of the babies to some of the snakes (before we realized it was an actual problem and not just a fluke of a couple old rats), and the snakes (adults and hatchlings) have shown no issues. Despite this, I'm afraid to feed anybody off unless I can pinpoint exactly what the problem is. One thing to lose a rat colony, another to lose all the snakes as well


Going to see if I can't do a huge clean of the entire system, add some ACV to the water, and talk to our vet about a huge dose of antibiotics. At the rate we're going, we'll be out of adult rats in antoher week or two, and we have 50+ mouths to feed weekly. Had a perfect system, even excess.. and now this. Ugh.

I appreciate any critical thinking, and really hope I can get this fixed. Not looking forward to starting up a new rat colony from the ground up.

[gsarchie]

No bueno! Hopefully you get it figured out or at least stop losing the rats. Definitely keep this updated as I am quite curious as to how this will turn out.

[KLMuller]

Maybe the straw was moldy, I know you said you only used it in one rack, but rats are very sensitive to molds.

~ Karl

[angllady2]

It is rare to see something kill so fast, but I suspect mycoplasma. All rats carry the bacteria, and under certain circumstances, the bacteria explodes and overwhelms the immune system and causes death.

The only way to be sure would be to take one of the newly deceased rats and refrigerate it until you can get it to a vet for testing.

Gale

[Anatopism]

Straw was definitely not moldy. Was only in there a week, mixed with pine, and was they were the driest tubs of the lot. If it was mold strong enough to kill off rats 15 feet away, it would have harmed more than just the two pulled out of the straw racks. Total of two rats died from one single straw-tub. First was the male breeder among the 6 a few days ago, replaced him with a different male breeder, who was dead this morning.

It is rare to see something kill so fast, but I suspect mycoplasma. All rats carry the bacteria, and under certain circumstances, the bacteria explodes and overwhelms the immune system and causes death.

The only way to be sure would be to take one of the newly deceased rats and refrigerate it until you can get it to a vet for testing.

Gale

I was thinking mycoplasma as well... I've just never seen them die so quickly. If it is illness, I'm hesitant to treat them, and just contribute to a colony that is weak and will pass on weak offspring. Unfortunately, VERY limited on funds until Friday (waiting on money from my slacker roommate who is always a month late in paying her share of utilities). Will see about getting a rat in for a necropsy as soon as I'm able.

At the very least if I can do that I will have an idea if it's safe to continue feeding them to the snakes. If it is safe to feed to the snakes, I'm leaning towards a mass gassing/cull, freezer bags, and starting a completely new colony.

[wilomn]

If you're adding new blood every few weeks it's possible one of two things did you in.

You might have simply brought in a virus on your clothing or hands or transport containers.

You may have gotten babies that appeared healthy because they were fresh off their mom's and were getting antibodies through their milk. It can take 4 months, or longer, for symptoms to manifest.

Have a necropsy done on a fresh one. It's the only way you'll know what you're dealing with.

Heck, you might have been targeted by a whacko animals rights nutjob who's figured out how to slip some poison into your colony, but that's a bit of a stretch.

[Anatopism]

If you're adding new blood every few weeks it's possible one of two things did you in.

You might have simply brought in a virus on your clothing or hands or transport containers.

You may have gotten babies that appeared healthy because they were fresh off their mom's and were getting antibodies through their milk. It can take 4 months, or longer, for symptoms to manifest.

Have a necropsy done on a fresh one. It's the only way you'll know what you're dealing with.

Heck, you might have been targeted by a whacko animals rights nutjob who's figured out how to slip some poison into your colony, but that's a bit of a stretch.

I sure hope it isn't some nutjob. We did lay a small amount of poison under the house about a month ago due to an adult getting out, avoiding all other traps, and trying to eat the chickens. That rat has since been caught, and there is no other possibility for the poison to have reached (or still be reaching) the rats as they are currently - We even had an ASF that was loose, running in the same area as the loose Norway, eating off the same ground, who was caught, thrown into a cage, and has been there 2 weeks showing no illness. Is it possible for ASFs to be magically immune to poison that kills other rodents? We've thrown out the old bag of food and have freshly opened bag of bedding and food, for fear that the 'poison' rat somehow contaminated the food previously in the garage, but have seen no change.

The landlords said there has been a rat problem once in the past, I'm worried that wild rats may have contaminated the colony, but no rat food, chicken food, or our dog food, has gone missing in the few months we've been here. There has been no mysterious rat droppings except for under the dryer when the one escapee was missing.

We do have a family of starlings that is living in a little enclosed space between the roof and the ceiling of the garage, and one got into the garage two days ago, but even he had no mites or external visible parasites when I looked him over (most baby birds I come across are covered in crawlies). No other starling encounters in the garage before or since

We've only gotten new blood from a single location, and I've since messaged him about if he's seen any issues with his rats currently or in the past. All rats we've gotten have been breeder sized females. Any babies we've gotten have gone straight into the snake room, rather than being raised up, but the idea of an illness not yet manifesting is a great point that I hadn't thought of previously.

I'm going to check them tonight and see how many of the rats that are alive were breeders from our supplier, and how many were there previously. I'm now curious if we've picked up rats that have a stronger resistance due to being raised in one particular environment, and if the rats that we had before are the ones taking a hit. I wonder if all the healhty mom's on babies at the moment were directly from or descended from our 'new blood' stock.

The symptoms just before they die is wheezing, sucked in sides, excess porphyrin. A couple have had purple lips/noses (lack of oxygen), but most of them show only the first symptoms.

[satomi325]

If you do indeed suspect myco, but don't have the funds for a vet, you can get Tetracycline antibiotic powder found in the fish section of any pet store.
You just have to mix it into their drinking water. Most vets will usually prescribe Baytril for rats, but Baytril isn't good for pregnant/nursing does or growing pups under 4 months of age. It will promote bone deformities.

Tetracycline is safe for all rats. (w/ or w/o myco)
I've had much success treating myco flare ups with this with no negative effects. And I have confirmed it's safety with some vets.

This is what I get:

It comes in packets of 10. Each packet contains 50mg of powder. One packet can be used on a 16qt water bottle. A box runs about $11 at my local pet store.




I brought in new blood into my small colony last fall. The new rats I brought in had myco and I didn't realize it at the time. And it spread to 80% of my rats. I treated them w/ Tetracycline powder and now they're all fine. I did have one death, but that was one of the new rats. He showed the same symptoms you're describing. The rest were just sneezy.

[Andybill]

Wow that sucks. I am starting a colony now and have been doing a bunch of reading up on care and what to expect/watch out for. I also will be keeping an eye on this thread as I am curious to know what the problem is. I hope you can figure it out soon. Good luck!

[Anatopism]

If you do indeed suspect myco, but don't have the funds for a vet, you can get Tetracycline antibiotic powder found in the fish section of any pet store.
You just have to mix it into their drinking water. Most vets will usually prescribe Baytril for rats, but Baytril isn't good for pregnant/nursing does or growing pups under 4 months of age. It will promote bone deformities.

Tetracycline is safe for all rats. (w/ or w/o myco)
I've had much success treating myco flare ups with this with no negative effects. And I have confirmed it's safety with some vets.

This is what I get:

It comes in packets of 10. Each packet contains 50mg of powder. One packet can be used on a 16qt water bottle. A box runs about $11 at my local pet store.




I brought in new blood into my small colony last fall. The new rats I brought in had myco and I didn't realize it at the time. And it spread to 80% of my rats. I treated them w/ Tetracycline powder and now they're all fine. I did have one death, but that was one of the new rats. He showed the same symptoms you're describing. The rest were just sneezy.

Honestly, I'm hoping it's an illness, and not some freak way they got poisoned. I keep thinking over all the possibilities, and still leaning towards illness/disease, just by how it's spreading, and how certain rats seem perfectly fine, and others jsut drop off. Their gravity water bins have lids on the top, and I've checked them several times for any contamination. Not possible for a poisoned rat to get into the water, but I suppose it is possible it's gotten dirty somehow, or is growing something that isn't visible. Still, the thought that I've caused this because of putting poison out, is beating me up.

Annoyingly, I'm also rarely every this close on funds, but it's been one of those months. Everything at once, you know?