Message Number: YG2040 | New FHL Archives Search
From: RRC
Date: 2001-04-02 09:04:00 UTC
Subject: Re: Sukie on Furballs

A lot of the stuff has been snipped to save space and I encourage people
interested in this thread to read the earlier posts if they have questions.

Bob wrote:
>>Hair is very resistant to digestion and hair passing out
>>the digestive system is more-or-less unchanged.

Sukie replied:
>If fur remains largely unchanged by the stomach acid
>then I really have to wonder even more seriously how much of a part
>the bedding played in this particular furball, esp. since within the
>content there were recognizable hairs as a minor component.

Bob responds:

Remember I also said:

>I know of no study which has documented hair
>diagenesis (diagenesis is a type of decomposition) from recovered
>hairballs and I have done nothing along those lines, so I can't say how
>much the hair is changed from long-term exposure to stomach acids.

Hair that makes it through the digestive system and recovered in scat is
not exposed to the same environment as the hair gummed up in a
trichobezoar stuck in a stomach for who knows how long. While hair is
acid resistant, it is not totally so, so those hairs recovered from
long-term hairballs may have undergone significant morphological change.
I know of no study which has addressed this issue and I haven't looked
at it myself. The trichobezoars I have on hand are promised to someone,
but I can look at a few in the future to see if there is any diagenesis
of the hair. I am not sure how I would be able to correct for time,
since I would have no idea how long the trichobezoar was in the stomach.
Perhaps an alternative method would be to expose hair to HCl for
specific times and look for diagenetic change.

Bob wrote:
>>Nonetheless, hair is easily distinguished from artificial fibers.

Sukie replied:
>I am not sure how much of the fabric is natural and how much
>artificial, but would like to know how to tell fibers apart from fur.

Bob responds:
Ferret fur is not in any of the published works illustrating fur types
for identification that I own or have ease of access. But that doesn't
matter because you own ferrets. Brush your ferret over its ENTIRE body
and pull the hair from the brush. Wash the hair in distilled water and
air dry. Under a dissecting scope and using a fine brush, separate the
hair types from each other and segregate by size, color ad morphology.
Fix the hair to microscope slides using conventional mounting
techniques. Make micrographs of the various fur types and print for reference.

Or you can simply place a few known hairs that sort of look like the
ones in question on the slide and compare them to the unknowns. If they
match, it's ferret fur. If not, then it is something else.

Here is a clue. Ferret underfur is transparent (the white color is an
optical effect rather than due to a pigment, much like why whole milk
seems white, and defatted milk turns bluish). The guard hairs are
pigmented in the upper half to 2/3rds only, the lower parts of the
shafts also being transparent.

Artificial fibers are pigmented throughout the length and width of the
fiber (although they may appear somewhat transparent). On extreme
enlargement, they are uniformly smooth, but hair is rough and may look scaled.

Bob wrote:
>>In wild animals, this bulk typically helps move hairs
>>through the digestive system.

Sukie replied:
>On that score I have wondered about insect exoskeletons, as in giving
>meal "worms", as a possible diet change if they take to them. Any
>data on if those might be useful as bulk?

Bob responds:
The keratin in exoskeletons is not digestible at the rates ferrets push
it through the digestive system, so the ease of intestinal passage would
be dependent upon the size of the particles swallowed. For a segmented
animal like a meal worm, I would suspect the exoskeleton would fall
apart and not be much trouble. For some other animals, like beetles or
spiders, depending on the size of the segment and the ferret's
willingness to chew it, I would have more of a worry.

I have inspected more than 1000 carnivore scats, including some
extremely unpleasant dissections of puma scat after it consumed deer. In
that number was about 150 mink scats collected in the eastern foothills
of Central California. Those scats contained frequent insect parts,
notably legs and carapaces, and they were crunched enough to make most
identification impossible. I would suspect the same from polecats. But
pet ferrets who never learned how to eat insects? I don't know. I do fed
my ferrets the occasional cricket as a treat and have never had a problem.

Sukie replied:
>Our's do get powdered bone when I boil down a chicken and then powder
>those epiphases which are calcified enough to be hard, but not so
>fully calcified that they form splinters. I simply am not wild about
>what happens when a diet containing larger bits of bone goes wrong.

Bob responds:
Bone powder in stomach acid does the same basic thing that happens with
you eat a Tums; it dissolves and buffers the stomach acids. Bone salts
are extremely sensitive to the presence of acids and dissolve on contact
(Want to see a picture? I have lots!). That is the difference between a
ferret swallowing a fragment of bone, a fragment of keratin, or a chunk
of rubber. Both the keratin and rubber are essentially unaffected by the
stomach acid and try to make it through the intestines with all their
sharp edges. Bone, on the other hand, is at least partially dissolved,
which rounds and smoothes the corners, making the passage easier.

Bone has two components which are important nutrients: the organic
protein matrix (various collagens) and the inorganic bone salts
(hydroxyapatite). The HCl in the stomach rapidly reacts with the bone
salts, dissolving them on contact. Later, digestive enzymes attack the
protein matrix, digesting a minute fraction. The end result is the bone
is rounded, pitted, and smoothed compared to the original fragment
swallowed (If you have access to a good library, look up a copy of Peter
Andrews' "Owls, Caves and Fossils." Wonderful pictures of exactly what I
am talking about, even if some of his conclusions are wrong). Bone
powder, depending on how fine it is, the amount, and the amount of HCl
excreted by the stomach, would probably completely dissolve and wouldn't
be useful in transporting hair.

Ferrets are not dogs; they don't gulp chicken bones and get them stuck
in their throats. Most of the concern about ferrets eating bone is
exaggerated. Ferrets are obligate, primary carnivores and evolved (as
polecats) eating animals containing a lot of tiny bones. If they
couldn't handle it, they wouldn't be here now, but instead stored in
some museum drawer as an example of yet another extinct animal. I feed
my ferrets whole chicken bones on a daily basis. The ferrets eat the
soft ends, chew or scoop the marrow, then hide the hard diaphyseal
"tubes" for me to find and save for my own research (I've compared them
to bones recovered from known mink caches and the chew marks and method
of nutrient extraction is essentially identical. I am always looking for
bones chewed by carnivores).

Of course, the odd ferret may have a hard time with bone, especially
those who have never learned how to eat it. They can cut their gums, or
even get a sharp fragment lodged in the back of their throat. There is
even the remote possibility that a sharp diaphyseal fragment could
puncture something. But I have averaged about 20 ferrets in the last 5
years, fed they bone DAILY and have never had a problem in more than
36,500 feedings (1 bone feeding per day x 5 years x 365 days per year x
20 ferrets = 36,500 individual feedings, not counting the years prior to
this then I owned less ferrets). I have personally seen more ferrets
choke on kibble than on bone, but I allow that many people fear feeding
bone to their ferrets, so I try to accept their reservations. Can a
problem happen? Of course it can! But the probability of it occurring is
very small.

Bob wrote:
>>There could be other
>>factors at work; my ferret free roam, so they don't perform extended
>>ritual grooming and other habits of boredom which might increase
>>hairballs in caged ferrets.

Sukie replied:
>We find that grooming is something that our's use more a cultural
>cement than as a way around boredom -- rather like primates use it.
>Perhaps your household's culture differs from our's in that regard.

Bob responds:
Probably not much different. I was speaking more of those ferrets who,
due to cage stress or boredom, groom themselves constantly. More of a
neurotic behavior than a socializing behavior.

Sukie replied:
>Not the ones that seem to make up the majority of the furball; those
>are KINKY, thin, and short when seen under the microscope, not
>slicker than hairs...

Bob responds:
Those could still be ferret hairs. Hair takes on different morphology
depending on site of origin. Maybe the short kinky hairs you are seeing
came from the lower abdomen, or from the ears, or someplace else where
they don't appear to look like the typical hair. Not all underfur looks alike.

Bob wrote:
>> not what I would suspect as being
>>something that might START a hairball). After all, hairballs are found
>>in a lot of animals who never come into contact with artificial fibers.

Sukie replied:
>Except that if that clearly were the cause we'd expect to have had
>furballs in the many years before, give that the diet is pretty well
>of the same general type and range, so it's certainly not clear-cut.

Bob responds:
But ageing causes significant differences. Not that I would know...

My ferrets live on fabrics with a lot of fuzz, and I've even seen some
in the scat when a new blanket is occasionally chewed up in play. Yet my
ferrets have never had a hairball. Maybe there IS some artificial fuzz
in the hairball, and maybe more fuzz than hair, BUT that doesn't mean
they are correlated. Maybe it does. I don't know.

Bob wrote:
>>If you like, I can look at your hairballs and identify the fibers.

Sukie replied:
>How about if you do part of it, and I save a bit for a different
>approach in case that option pans out? I got only one of the
>furballs. How large a sample do you need?

Bob responds:
To be a true picture, it would have to be a random sampling of various
parts of the trichobezoar.

I think the important question should NOT be "Are there artificial
fibers in my hairball?" I think it SHOULD be "Does it MATTER if there
are artificial hairs in my hairball?" If the answer to the second
question is no, then the first question becomes trivial.

This reminds me of the old saying, "99% of all people who get rectal
cancer use toilet paper, so toilet paper causes rectal cancer." Well,
maybe 99% of all hairballs contain some proportion of artificial fibers,
but perhaps the presence is an epiphenomenon of ferret housing, not a
contributing factor to the formation of trichobezoars. To me, the
problem is the current ferret diet may supply all the necessary
nutrients ferrets may require, but I seriously wonder if it supplies
those non-nutrients the ferret's digestive system evolved to eliminate.
In other words, we may be feeding our ferrets the correct nutrients, BUT
are we feeding them the correct food?

Bob C