#manx rats

[ithinkratsshouldvote]

"hairless rats have all kinds of problems and people breed those all the time!" is not the airtight argument in favor of Manx rats so many people seem to think it is

"you just hate breeders in general" I'M STARTING TO, MAN

[ithinkratsshouldvote]

My thoughts on which (domesticated norway) rat varieties are ethical to breed en masse and popularize as pets are complicated by the fact that rats are a highly invasive pest species.

From a companion animal standpoint, I don’t really see a good reason to deliberately cultivate a population of rats with no tails, or no hair, or curly whiskers, or impaired vision coupled with an impaired sense of smell and/or reduced olfactory response (which some studies suggest might be the case for rats with albinism).

If the goal of breeding is to improve the health of the species overall—which many breeders do claim—then pursuing these varieties feels counterintuitive. You can’t, to the best of my knowledge, breed better eyesight into a rat with albinism, or alternative methods of thermoregulation into a rat with no tail.

Theoretically these things might be possible, many generations down the line, but the likelihood of any pet breeder actually achieving this—let alone in a timely manner, without first producing hundreds or thousands of impaired rats—is slim.

And most, in my experience, aren’t even trying to. Every manx breeder I’ve seen who talks about “improving the health of the variety” speaks as if this task is already complete in their line, and/or leaves thermoregulation out of the equation entirely, and simply assumes that because their manx rats don’t visibly struggle with mobility or show noticeable signs of pain, they must be suffering no ill effects from the fact that they’re missing a huge chunk of the body they evolved to inhabit.

But if we’re trying to be ethical from an ecological standpoint, we have to look at the reality that sometimes pet rats escape (or are released) into the wild, and reproduce. And from there they can destroy crops, invade homes, spread diseases, and out-compete or directly attack native wildlife. These threats are not unique to rats, but should be considered when trying to justify bringing more of them into the world.

Different sources state different litter sizes, with the highest maximum I’ve seen so far being 18 and the lowest maximum being 12. Rats can reach fertility at just a couple months old, sometimes as early as five weeks. Their gestation period is only three weeks, and they can become pregnant almost immediately after giving birth.

(This is not good for them, especially at a young age, just to be clear.)

One ecological measure might be to breed a line of rats that tends towards smaller litter sizes, lower fertility rates, and/or early infertility—if that’s even possible to achieve without other health complications. I have no idea.

Even if it is possible, however, this would inherently complicate every other aspect of the program. Rats’ fertility is one of the things that makes them such an efficient animal to breed. Lowering the litter size by a wide enough margin to make an ecological difference would also drastically reduce the chances of producing the specific traits you’re aiming for.

So it becomes a balancing act of breeding rats who can exist comfortably in a domestic situation, but which would not thrive in the wild.

Part of this concept—that a domesticated animal does not need the same traits as their wild counterparts—has been put forward to justify the breeding of manx rats. I have already explained at length why I do not believe manx rats’ impairments can be adequately accommodated in even the cushiest pet home. Tumblr hates links, but it’s the first post on this blog.

So where is the line drawn?

Let’s look at Alaska. Only one variety of Norway rat is allowed in Alaska: PEWs. Albino rats, aka Pink-Eyed Whites.

PEWs have worse eyesight than the average rat, may have a reduced sense of smell and/or reduced olfactory response, and are—as the name suggests—white. All of this in combination makes them easier to spot and catch, whether they’re being pursued by a predator or a human.

I am having trouble finding any sources that confirm this is why only PEWs are allowed, but this has been discussed frequently in rat circles. I might question how effective this is in the snowier regions, where a white animal would presumably have an easier time blending in, but I could be wrong about that.

Either way, I am just using Alaska as an example. In addition to the statewide PEW-only rule, some places—such as Anchorage—ban pet rats altogether.

So, does this work? I can’t say for sure, but an article posted on the Alaska Department of Fish and Game's website in December of 2020 states that Anchorage "may be the largest rat-free port in the Northern Hemisphere." (Source will be linked in a reblog.)

If we say, for the sake of argument, that it does work, and if this were implemented on a wider scale, is the quality of life tradeoff acceptable?

I don’t know.

The coat color making the rats more visible to predators, yes, absolutely. A pet rat (being kept responsibly) does not need to blend into its surroundings, and should not be affected by this in any way.

Rats don’t seem to rely on their eyes very much in the first place, so I am not overly concerned with that aspect, either. Or I wouldn’t be, if it wasn’t potentially coupled with a reduced sense of smell and/or reduced olfactory response. I have not yet read the studies that suggest this, which is why I keep referring to it as a hypothetical, but those studies were quoted in a source that I generally trust.

Sense of smell is extremely important to rats, and the results of those studies suggest a vast difference in rats with albinism.

Interestingly, one of those differences might directly affect reproduction rates amongst rats who survive long enough to reproduce in the first place:

Quote from "The rat's world of smell" by Anne Hanson on RatBehavior dot org. (Source will be linked in a reblog.)

Sachs (1996) tested male albino and pigmented rats' response to the remote cues of a female rat in heat. Sachs used a testing chamber that was divided in half by two wire mesh screens separated by a few centimeters, so the male rat on one side could see and smell a female in heat on the other side but could not touch her. Sachs found that 83% of pigmented male rats became aroused, but only 4% of albino rats did.

This could potentially curb escapee reproduction rates without affecting a breeding program, if the lack of arousal only indicates that the albino rats were having trouble detecting the females. A rat who is able and willing to reproduce when offered the chance, but who cannot easily find a mate in the wild, could be what we are looking for.

But the question of QOL remains. I can’t say for certain whether a pet rat is impacted by an impaired sense of smell on a level that makes their production unethical, if that is indeed true of PEWs. I can say I would be fighting a losing battle on multiple fronts if I did take that stance. I am also unsure how albinism might impact a (non-hairless) rat’s risk of sunburn, and whether light actually hurts their eyes.

Rex rats are another case where I’m on the fence. Perhaps a rat who lives in a nice cage in a climate-controlled room, where all of his needs are fulfilled and there are no active dangers to detect, will never actually suffer (beyond mild inconvenience) for his reduced field of whisker “visibility,” or his lack of fur.

But this case raises questions in the other direction. Is a rex rat meaningfully less able to thrive in the wild than a non-rex rat? How much of a difference do shorter, curlier, fewer whiskers make when being stalked from afar by a bird of prey? I don’t know.

Rexes with bald patches, or who lack fur entirely, would be more prone to both sunburn and low temperatures. But how much does that matter, in terms of pest control? A sunburned rat can still chew through plastic or dig up crops. A cold rat may be even more determined to find its way into a heated garage.

I might hesitantly propose a less stringent version of the current Alaska rule. One that imposes restrictions on coat color, depending on regional camouflage options, but doesn’t require albinism. However, this lacks the potential reproductive stumbling block of the PEWs, as well as their potentially reduced ability to smell predators.

There isn’t a perfect solution, and I don’t have a neat ending planned for this post, and on an immediate human level I would honestly be very sad if rats of certain colors could only be bred in certain regions. This is just something I think about a lot.

[ithinkratsshouldvote]

“It doesn’t bother them”

I’ve certainly been guilty of ascribing thoughts and feelings to my pets. But it’s something I try to be cognizant of, especially when it comes to their health.

As important as it is for pet owners to make sure we’re being objective about things that might affect our animals’ quality of life—and it is important—I cannot overstate how vital it is for breeders.

When a pet owner assumes it is easy to detect pain in rats, their rats might suffer.

When a breeder assumes the same thing, they might produce and distribute dozens or even hundreds of suffering rats.

I go on about Manx rats on here because Manx advocacy is getting more and more aggressive in online rat owner and breeder circles. I’m in multiple groups where the mods themselves openly side with the Manx breeders/enthusiasts, and scold other members for speaking against the practice when the topic comes up.

The narrative that Manx rats “get around just fine” is bad enough. You don’t know that rat isn’t in pain. I saw a prominent Manx breeder go from asserting that their Manx rats climb/play/wrestle “just like” other rats to, in the same comment, casually stating that they sometimes take longer to right themselves when flipped on their back, especially as babies.

The mobility angle is by far the one I see debated most often. Thermoregulation generally seems to take a back seat.

But in one of these arguments, I actually saw two breeders assert that their Manx rats have no trouble regulating body temperature. Which begs the question:

How do you know that?

The best climate control in the world will not negate the reality of a body that cannot carry out its evolved method of thermoregulation. And overheating is not an on/off switch. Between “perfectly fine” and “heatstroke,” there is a spectrum of varying levels of “uncomfortably warm.”

So, are you monitoring their temperature? How? How often? In which regions of the body? How do you determine how “easy” it was for them to reach the temperature they’re at? How do you know whether or not they’ve learned to modify their habits to minimize the generation and retention of body heat? How do you know they aren’t dealing with constant low levels of physical discomfort that they’ve just learned to tolerate?

You don’t. Just like you don’t know their mobility isn’t affected.

Rats. Hide. Pain.

It’s part of why they’re known for “suddenly” dropping dead with no visible symptoms. Any good breeder knows this, and takes care to monitor their rats’ health with every tool available, including scientific data that may or may not back up their own confirmation bias.

One of these people was demanding scientific sources, which frankly tells me everything I need to know about their breeding priorities, because it took me two minutes on Google to find some that lay out exactly why a rat’s tail plays a vital role in thermoregulation. I won’t link any here because Tumblr hates links, but I quoted and linked to one in my first post on this blog.

This data exists. It just isn’t titled “Here’s Why You Shouldn’t Breed Manx Rats.” You have to look at the facts as they currently stand, and apply a little bit of common sense.

[ithinkratsshouldvote]

"manx rats don't have tails because god wanted them to be special" is a new one

[ithinkratsshouldvote]

really funny in a sad sort of way when Manx rat advocates are confronted, and respond with "Well, are you also against these other Problematic rat varieties?"

and either the person they're arguing with is like "I mean, yeah. Yes. I am. Those are also bad."

or the varieties they listed can actually be uncoupled from their associated problems.

Like, there is a huge difference between "Silvermane rats often have health and temperament issues because they're a very young variety and we haven't worked out all the kinks yet" and "I think it's fun to breed rats that are missing half their spinal column and their primary source of thermoregulation."

[ithinkratsshouldvote]

What is the point of deliberately breeding tailless rats? Of advocating for the breeding and selling and marketing of tailless rats? Of insisting that modern-day Manx rats are "not really disabled" and all the warnings online are "outdated"?

I've seen the claim that it makes rats more appealing to those who are creeped out by their tails. But why on earth would a rat breeder cater to people who are disgusted by a basic aspect of a rat's body? Why would that be the customer base you want?

What do you think the majority of these owners are going to do when things get gross? You think they'll be willing to monitor a rat's poop to keep an eye out for digestive problems? You think they'll tolerate getting pissed on? You think they'll administer eyedrops, or inspect a wound, or remove a fucking penis plug?

Even if every single owner took fantastic care of their tailless rats, that still would not outweigh the harm caused by deliberately breeding them, and driving up demand by posting "cute" videos and pictures on Instagram and Facebook.

Because:

Rats need their tails.

We have scientific studies explaining exactly why rats need their tails. Here is a short excerpt from just one paper, Thermal Biology of the Laboratory Rat (Gordon, 1990):

Several physiological and physical properties make the tail of the rat crucial in the dissipation of body heat:

(i) it lacks fur which accentuates heat loss;

(ii) it is highly vascularized, permitting a high rate of blood flow during heat stress; and

(iii) it has a relatively high surface area:volume ratio which further aids in heat exchange.

The specialized adaptions of the tail can be illustrated by the fact that it comprises approximately 7% of the rat's total surface area (Lin et al., 1979); nevertheless, under steady-state conditions, approximately 20% of the total heat production is dissipated from the tail (Rand et al., 1965; Young and Dawson, 1982).

Surgical amputation of the rat tail severely impairs thermoregulation in the heat (Stricker and Hainsworth, 1971; Spiers et al., 1981).

Taillessness is not an independently harmless trait that can theoretically be separated from a problematic gene. It is inherently detrimental to the rat.

Even people who claim to produce "healthier" tailless rats seem to focus solely on the (CONSIDERABLE) problems of balance and mobility issues and spinal deformities and other more obvious complications, while brushing off concerns about thermoregulation and undetected pain.

I've seen the argument that you can compensate for the temperature problems with air conditioning, and as a human being with fucked up thermoregulation, I am personally and emphatically telling you that it does not work like that. Environmental temperature control is a mitigating factor. Not a magical, disability-erasing button. Tailless rats take longer to cool down when overheated, period. And you cannot guarantee that will never happen, because rats are already prone to overheating.

This has more ramifications than the risk of death by heatstroke. Thermoregulation affects quality of life on a minute-by-minute basis, which is especially concerning in a species that is incredibly prone to stress-related health problems.

"My Manx rats seem fine" does not hold water as a justification for mass breeding. Rats are prey animals. They hide pain. Even when they do express discomfort, it's easy for us to miss. Even when we're looking objectively, and especially when we're looking through the veil of confirmation bias. Which is why it's important to pay attention to scientific studies that tell us exactly how rats work.

"I'm trying to improve the health of the species." Well, you're doing a shit job! Try starting with rats that haven't already been sabotaged by the congenital lack of a major body part. If you have the time and energy and money to invest in deliberately breeding "healthy" Manx rats, you have the time and energy and money to invest in breeding that gene out of your lines.

[karasratworld]

Breeding Dwarf and Manx Rats

Well yeah- breeding rats, as with breeding any animal, is riddled with controversy. I don't usually tend to agree with rescues on a lot of things. I think rescuing is amazing if you can do it but I think a lot of people in the rescue world get extreme and unreasonable. My mom works for a golden retriever rescue in the DC metro area and I used to volunteer with the SPCA and yeah...it gets to be too much sometimes in my opinion. But most of what they stand for is great- just saying that some of my opinions probably won't align with the rescue world.

But on the flip side the pet fancy can get too extreme with breeding for "breed standards". It happens in dogs obviously especially with pug-faced dogs and things like that. Some breeders lose sight of the healthy and quality of life of their dogs in the pursuit of show perfection. I know there is lots of controversy with manx rats because of spinal deformities and temperature regulation and things like that in order to achieve the true tailless rat. But I also know there are lots of manx rats out there doing well!

Everyone has a different opinion. A lot of people are against breeding "mutations"- even dumbo and things like that. Technically all the colors and patterns are all mutations so I don't like that terminology at all. But yeah- I think so much of it depends on the quality of the breeder and where their lines came from and all that. Since they breed them, the obviously don't think it's unethical but it is definitely worth asking them about any health issues they've seen as well as the pros and cons of owning one (dwarf especially). I know dwarfs can be less prone to tumor issues because of the lack or reduction of growth hormones. As someone who has dealt with heartbreaking tumors in my standard girls, that is definitely a plus for dwarfs in my eyes. However, they may have other issues associated with the dwarfism- I don't know enough to say for sure but I know there are good people that breed dwarfs and manx rats and their rats lead happy healthy lives as pets and as breeders.

I tried to do a little research on forums and I found a lot of people stating that breeding dwarfs is unethical but not a lot of research or anecdotal experience to back it up so I would like to see some credible sources arguing one way or the other before I make up my mind for sure. And as always people are very defensive and get nasty quickly. I like to think of myself as a reasonable and calm person so if you would like to send me your opinion, please do so respectfully and I'd love to talk to you about it!