Which rabbit litter is best? Can the litter you use hurt your rabbit? Maybe, but it might not
be for the reasons you think...
Rumors about pine and cedar as small animal litter are all over the internet. Sites are reprinting and repeating information taken from two specific articles that pronounce pine and cedar shavings toxic.
But ... does Science beg to differ?! Read on to discover the truth about cedar and pine shavings.
This is a fairly long page - so we want you to know up front that pine shavings are just fine for rabbit litter, the nest box, and bedding. Pine is completely safe, and especially if it is heat-treated or kiln-dried.
Laboratories that do drug tests on rabbits are the
ones avoiding softwood shavings. This is in order to keep their
results standardized between facilities.
For pet rabbits and show rabbits, pine is completely safe for rabbit
litter, especially kiln-dried pine.
Kiln-dried pine is also the cheapest rabbit litter on the market. And
since it does a comparable job to all the other litters, pine shavings
as rabbit litter and rabbit bedding gets our top vote.
Bedding for comparisons with several other rabbit bedding
materials, and more recommendations.
The Cedar and Pine Controversy
Two online articles have almost singlehandedly destroyed the
reputation of pine shavings for rabbit litter. This is unfortunate, as wrong
conclusions have been drawn and then presented as fact.
For the rest of this page:
We’ll link you the the two articles (by
Dr. Flentke and Ms. Merriman) and outline their views, while including our
comments and observations for clarification.
We’ll also give you the much more balanced comments of
Lianne McLeod, DVM, rabbit expert on Ask.com.
Plus, in our Conclusion below, we’ll link you to
our synopsis of a very informative article that correctly presents and
interprets the misunderstood science.
Please read on, if you need to. (I found it very
fascinating! But then, as a past Registered Nurse, the science interests me...)
Cedar and Pine are both aromatic softwood shavings
The aroma comes from phenols in the wood
The distinction between softwood and hardwood rabbit litter comes because there isn’t near as much phenols in hardwood shavings, such as aspen and douglas fir
Phenols enter the rabbit’s system through the lungs inhaling the fumes
The body detoxifies phenols in the liver. This process is known to elevate the rabbit’s liver enzymes.
[What Dr. Flentke does not note, is that the rabbit's enzyme system is a NORMAL part of the rabbit’s antioxidant system - it detoxifies a great many substances in the rabbit’s body, and when it does so, the enzymes elevate and then return to normal. At any given time of the day, the rabbit may exhibit elevated liver enzymes as a normal part of health maintenance. Yes, phenols elevate liver enzymes; disease is not inferred from this mechanism.]
The same enzymes also remove drugs in a rabbit’s body
Some of the main drugs a vet may use are:
Opioid painkillers, such as butorphanol
Drug effectiveness when liver enzymes are elevated is reduced by over 40%, because the increased levels of liver enzymes washed the drugs out of the system much more quickly than normal.
[This is not a problem to the rabbit. It is a problem to the vet, who needs to know ahead of time to adjust the drug dosage. It is also a problem to laboratory researchers, who need to standardize their results with results from other laboratories. It is not a problem to the rabbit.]
This is the main objection to softwood litters.
An increased risk of cancer is currently talked about, but not proven. Evidence is suggestive at best (extrapolated from considerations in humans).
DON’T use Ponderosa Pine needles as an alternative. In other domestic animal species, including cattle, they have caused spontaneous abortions and other hormonal disturbances.
[Dr. Plentke didn't elaborate on the fact that the study was specifically done in order that three pharmalogical drug labs could standardize their drug test results between them. The tests were not triggered from any evidence of illness in rabbits or rats due to cedar or pine shavings. The good thing that comes out of this study: Veterinarian surgeons now know to adjust drug dosages for rabbits on untreated cedar or pine shavings. (Unless you live near a sawmill, I'm not sure where you'd find the untreated shavings.)]
Ms. Harriman states that rabbits with liver disease died because the liver could not eliminate toxins from the blood.
[But wait -- this is in direct contradiction to Dr. Flentke, who states that elevated enzymes eliminate toxins too fast. Actually, those rabbits may have died because they had damaged livers to start with, most commonly from hepatic coccidiosis (the liver strain), but the cause could have also have been from weakened immunity due to other chronic disease, say, snuffles. According to some reports, the incidence of the disease in pet rabbits (including rescue rabbits) is as high as 90%.]
"Liver damage," she states, is caused by cedar or pine fumes, and results in a "large number of deaths due to liver damage and anesthesia fatalities."
[This is a misguided leap of imagination. Liver damage and death...okay. The cause being shavings fumes...no. There is not a teensy shred of scientific evidence anywhere that indicates liver damage from cedar or pine fumes. Elevated enzymes in this case is not an indication of liver damage, but of a system that is working correctly. See our Pine Shavings page for what happens when enzyme levels start dropping.]
If using shavings, ensure your litter box is well-ventilated, and obtain blood work every few months.
[Unless your rabbit is showing symptoms of something, the blood work is overkill. More concerning, a rabbit could have normal liver enzymes and yet have liver damage from, say, coccidiosis. Details on the Pine Shavings page.]
Alternatives to shavings:
Ms. Harriman's list includes Carefresh® - dust free, lightweight, super-absorbent, non abrasive, non-toxic
[Carefresh?? Here’s some science you need to see. According to the following study, Carefresh ranks poorly at ammonia control in your pet's environment, a potentially serious threat to health in poorly ventilated areas.]
Table 2 Explanation: "The mean ammonia concentrations in static cages housing mice on CareFRESH Ultra bedding were significantly higher than the means for all the other bedding treatments (Table 2). Unexpectedly, the ammonia concentrations in cages housing mice on CareFRESH Ultra bedding were very high at 2 weeks (65.4 to 390.2 ppm), so we removed that group from the study. Mean ammonia levels in cages with pine shavings, Cell-Sorb Plus, a mixture of pine shavings and ALPHA-dri, and Bed-O'cobs did not differ significantly from each other but were significantly different from other bedding types." (Excerpted from "Evaluation of Cage Micro-Environment of Mice Housed on Various Types of Bedding Materials," by ELLEN SMITH, JASON D. STOCKWELL, PHD, ISABELLE SCHWEITZER, MS, STEPHEN H. LANGLEY, BS, AND ABIGAIL L. SMITH, MPH, PHD)
Studies of laboratory animals have shown fairly dramatic changes in liver enzymes on animals housed on cedar bedding. This in turn can affect the metabolism of drugs. [This is the only concern noted, and she references only cedar, while noting later that pine emits volatile oils but no clear conclusions can be drawn about pine. Our Pine Shavings page explains the normal, healthy, daily liver enzyme fluctuations.] Still, not much info on a direct link between these changes and disease or clinical symptoms.
Better to avoid cedar shavings. [(Unless you love the smell, there is very little reason to choose cedar over the very economically priced pine)]
Pine - heat-treating pine shavings may reduce the levels of aromatic hydrocarbons. Kiln-dried pine is considered safe.
Many pet products are heat treated.
Surprisingly, CareFresh Ultra results in the highest levels of ammonia
[Yes...10 times higher than its next-highest competitor - pine shavings (see Table 2 above).
See our CareFRESH Pet Bedding page for our evaluation of CareFRESH.
Conclusion to the Rabbit Litter Discussion
My comments in green above are drawn partially from my Registered
Nursing training and experience, and from an excellent article written by Ms.
Corinne Fayo entitled "The Truth About
Ms. Fayo did all the research, and granted us permission to write a synopsis of her work which can be found here: Pine
Pine is an ideal bedding and litter product, superior to both cedar
and CareFresh, cheaper than hardwood beddings, while being essentially equal in
quality to hardwoods and other excellent rabbit litter products.
What's not to like about pine?!
We do recommend heat-treated pine shavings for rabbit litter. We've used it in our nest-boxes for over 30 years. If this practice were toxic, we’d have seen significant health problems with very young kits. This has not been the case.
We know that some folks will still be afraid to trust the science, and that’s okay. But if you’ve read this far, perhaps we have laid your rabbit litter concerns to rest. Hopefully so!