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Posts Tagged ‘freezermas’

Sick feet, pig feet, boo hoo, in pain you are
Not well heeled; fate sealed, oh no, inflamed they are
And when your trotter’s on the floor
You’re nearly a good boar
Almost a porker

(corrupted from Pink Floyd’s “Pigs (Three Different Ones)” track #3 from the Animals concept album (1977). A song with quite a history- check out some more about it.)

It could happen...

It could happen…

Concept albums often weave back and forth between themes in a non-linear story, returning to refrains and leitmotifs to create their narrative weft and warp. This Freezermas, I’ve already woven in two legs and four legs, cats and other beasts, x-rays and more. Today, I tie in another thread, which extends throughout the blog, but especially into yesterday’s post. This post is about feet and health again. But it is also solely about pigs, which are cool animals whose biomechanics are surprisingly little studied.

It’s a shorter post (in contrast to the 11-17 minute Pink Floyd cousin song); a drum solo if you will; with just three images representing three big pigs and their funky feats of footedness, and the three days left in Freezermas. One image is about ongoing research; the other two about bizarre cases that kinda freak me out (enough to want to know more about them).

Stomach-Churning Rating: 4/10, not for gore but for surreality; things that should not be. Especially the 2nd picture.

pig gif

Above: X-ray GIF (may take a while to load) from our 3D XROMM analyses of foot biomechanics, here showing a pig studied by Dr. Olga Panagiotopoulou (also RVC Fellow Jeff Rankin; and Prof. Steve Gatesy at Brown University). With data like these, we not only can measure how the tiny bones move, but also get better estimates of the loads on the soft tissues within those feet. Those loads should relate to the risks of musculoskeletal injury or disease. This GIF is just a teaser for some fantastic 3D images we’re producing. The pig’s feet were normal. The odd little spheres on them are skin-adhered markers that let us compare how external estimates of skeletal motion compare to actual motion; normally this is a big source of error.

I know little about this case, posted on Reddit (link here), except that the overgrown, grossly deformed toes/hooves of this pig are like nothing I've seen before! This almost gave me nightmares. Poor chicken-footed pig!

I know little about this case (seems to trace back to an original Brazilian news story), posted on Reddit (link here), except that the overgrown, grossly deformed toes/hooves of this pig are like nothing I’ve seen before! This almost gave me nightmares. Poor chicken-footed pig. Foot deformities of this kind in pigs don’t seem to be as much of a problem as in cattle or horses; from the limited literature I’ve seen on this, they seem to have more problems with the soft tissues of their feet, such as  abscesses or inflammation of the digital cushion (padding) of the trotter.

Another crazy case; but this one I was able to track down more about after reading the Reddit post here. The Getty images page says: This photo dated November 24, 2011 shows a Chinese farmer showing off his prize swine, which he named 'Strong Pig', as the disabled animal keeps its 30kgs of body suspended in midair, in Mengcheng, east China's Anhui province. The pig has become an internet sensation around China due to its ability to walk around balancing on its two front legs. TOPSHOTS CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images)

Another crazy case; but this one I was able to track down more about after reading the Reddit post here. This news image page says:
“This photo dated November 24, 2011 shows a Chinese farmer showing off his prize swine, which he named ‘Strong Pig’, as the disabled animal keeps its 30kgs of body suspended in midair, in Mengcheng, east China’s Anhui province. The pig has become an internet sensation around China due to its ability to walk around balancing on its two front legs. TOPSHOTS CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images)”

Bipedal pigs– two legs good again? I guess so. Well done, Strong Pig. Well done.

Bipedal ability in injured/deformed/spooked quadrupeds is not so unusual- in addition to trained macaques and rats that have been scientifically studied, there are plenty of examples out there on the internet of videos/GIFs of bipedal cats, dogs, and so on… Post your favourites below. Hooray for the marvelous plasticity of the locomotor system! As Pink Floyd famously wrote, “Any fool knows a dog needs a home, a shelter from bipedal pigs.” (or something like that)

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Why should you care
If you have to trim my hooves?
I’ve got to move with good feet
Or be put down fast.
I know I should trot
But my old vet she cares a lot.
And I’m still living on stone
Even though these feet won’t last.

(mutated from The Who, “Cut My Hair“, Quadrophenia… from the heyday of concept albums and grandiose rock!)

Talkin' bout my osteitis?

Talkin’ bout my osteitis

Day Four of Freezermas. Four posts to go. I can see through time… Hence the silly title for today’s concept album track. Quadrupedophilia did not have a good ring to it, anyway.

Stomach-Churning Rating: 4/10. Reasonably tame; bones and hooves. Some pathologies of those, but not gory.

If Quadrophenia was the story of a man with four personalities (metaphor for the four band members), then quadrupedopheniaphilia is the story of how diverse forms of four-legged animals have lots of problems because of our exploitation of them, which leaves a crisis to resolve: Who are we? Are we caring enough to fix a bad situation we’ve created for our four-legged ungulate comrades?

Four legs good, two legs bad? Not really. I featured ostriches earlier this week and two legs are indeed pretty good. Four-legged cats are great, too. But four-footed big beasties with deformed hooves: those are bad all around. That leads to today’s topic…

But hey, happy 205th funkin’ birthday Charles freakin’ Robert Darwin!

Charles Darwin on his horse “Tommy” in 1868- from the Darwin Correspondence Project, https://www.darwinproject.ac.uk/darwins-photographic-portraits

Today’s post concerns a phenomenon that (Western) civilization has wrought with large hoofed mammals, and evolution is a big part of it (as well as biomechanics and anatomy) . Cynical perspective, with some truth to it: We’ve evolved larger and heavier animals to either do harder and harder work on tough surfaces like concrete floors and tarmac roads, or to stand around while we gawk at them or wait for them to get fat and tasty. Either way, the outcome should come as no surprise: their feet, the interface of that hard ground and their body, eventually start falling apart.

I’ve posted about this several times with respect to rhinos and elephants (here and here and here and here and here), but this post hits closer to home: what goes wrong with the humble hoof of our friend the horse, cow, sheep or other ungulate. It’s where the rubberkeratin hits the road. Ungulates have not evolved to live on dirty, wet concrete floors; to be obese and inactive; or to have hooves that don’t get worn down. So they suffer when they do encounter those modern conditions.

“No foot no horse,” they say, and it’s so true- once the feet start to go (due to hoof overgrowth or cracks, abscesses or other trouble), it’s hard to reverse the pathologies that ensue (arthritis, osteomyelitis, infections, fractures, etc.) and the animals start going lame, then other limbs (supporting greater loads than the affected limb) start to go, too, sometimes.

Jerry the obese, untrimmed-hoof-bearing horse.

Jerry the obese, untrimmed-hoof-bearing horse. “Turkish slippers” is an apt description. DM has more here.

We can do plenty about these problems, and the title track above explains one of them: trimming hooves. Hooves often get overgrown, and if animals are tame enough (requires training!) or are sedated (risky!), hoof care experts (farriers) can rasp/file/saw them down to a more acceptable conformation. If we don’t, and the animals don’t do the trimming themselves by digging or walking around or living on varied surfaces, then the feet can suffer. But there’s still not much evidence for most common species kept in captivity by humans that indicates what the best methods are for avoiding or fixing foot problems.

What we’ve been trying to do at the RVC is use our expertise in evolution, anatomy and biomechanics to find new ways to prevent, detect, monitor or reverse these foot problems. We had BBSRC grant funding from 2009-2012 to do this, and the work continues, as it behooves us to do… Past posts have described some of this research, which spun off into other benefits like re-discovering/illuminating the false sixth toes of elephants. We’re working with several zoos in the UK to apply some of the lessons we’re learning to their animals and management practices.

Above: Thunderous hoof impacts with nasty vibrations, and large forces concentrated on small areas, seem to contribute to foot problems in hoofed mammals. From our recent work published in PLOS ONE.

Foot health check on a white rhino at a UK zoo. Photo by Ann & Steve Toon, http://www.toonphoto.com/

Foot health check on a white rhino at a UK zoo; one of the animals we’ve worked with. Photo by Ann & Steve Toon, http://www.toonphoto.com/

If it works, it’s the most satisfying outcome my research will have ever had, and it will prevent my freezers from filling up with foot-influenced mortality victims.

Again, I’ll tell this tale mainly in photos. First, by showing some cool variations evolved in the feet of hoofed mammals (artiodactyls and perissodactyls; mostly even/odd-toed ungulates of the cow/sheep and horse lineages, respectively). Second, by showing some pretty amazing and shocking images of how “normal” hooves go all wonky.

Two ways to evolve a splayed hoof for crossing soft ground: 2 toes that are flexible and linked to big pads (camel), and 2 main toes that allow some extra support from 2 side toes when needed (elk). At Univ. Mus. Zoology- Cambridge.

Two ways to evolve a splayed hoof for crossing soft ground: 2 toes that are flexible and linked to big pads (camel), and 2 main toes that allow some extra support from 2 side toes when needed (elk). At Univ. Mus. Zoology- Cambridge.

Diversity of camelid foot forms: big clunky, soft Old World camel feet and dainty, sharp highland New World camelids.

Diversity of camelid foot forms: big clunky, soft Old World camel feet and dainty, sharp highland New World camelids. [Image source uncertain]

Moschus, Siberian musk deer with remarkable splayed hooves/claws; aiding it in crossing snowy or swampy ground. At Univ. Mus. Zoology- Cambridge.

Moschus, Siberian musk deer with remarkable splayed hooves/claws; aiding it in crossing snowy or swampy ground. At Univ. Mus. Zoology- Cambridge.

Tragulus, or mouse-deer, with freaky long "splint bones" (evolutionarily reduced sole bones or metatarsals) and dainty hooved feet. At Univ. Mus. Zoology- Cambridge.

Tragulus, or mouse-deer, with freaky long “splint bones” (evolutionarily reduced sole bones or metatarsals) and dainty hooved feet. At Univ. Mus. Zoology- Cambridge.

Overgrown giraffe hooves. An all-too-common problem, and one we're tacking with gusto lately, thanks to PhD student Chris Basu's NERC-funded giraffe project!

Overgrown giraffe hooves. An all-too-common problem, and one we’re tacking with gusto lately, thanks to PhD student Chris Basu’s NERC-funded giraffe project!

Wayyyyyyyyy overgrown hooves of a ?sheep, from the RVC's pathology collection.

Wayyyyyyyyy overgrown hooves of a ?sheep, from the RVC’s pathology collection.

Craaaaaaazy overgrown ?cow hooves, from the RVC's pathology collection.

Craaaaaaazy overgrown ?sheep hooves, from the RVC’s pathology collection.

If we understand how foot form, function and pathology relate in diverse living hoofed mammals, we can start to piece together how extinct ones lived and evolved- like this giant rhinoceros! At IVPP museum in Beijing.

If we understand how foot form, function and pathology relate in diverse living hoofed mammals, we can start to piece together how extinct ones lived and evolved- like this giant rhinoceros! At IVPP museum in Beijing.

So, what do we do now? If we love our diverse hoofed quadrupeds, we need to exert that quadrupedopheniaphilia and take better care of them. Finding out how to do that is where science comes in. I’d call that a bargain. The best hooves ever had?

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Freezermas continues with track 3 of our rockin’ anatomy concept album! The number of the beast today is 5 (five days to go in Freezermas!), and I will deviate from the rock/metal theme to embrace the other side of the tracks: hip hop and rap. The Beastie Boys and I go way back: their “Licensed to Ill” album was the second cassette tape I bought (I remember proudly showing it off in Geometry class, circa 1986/7), and still ranks as one of my favourite albums ever. Everyone should own a copy of that, and of this next album…

The Five Felids, featuring KC

If only MCA were still alive to do this follow-up album…

The Beastie Boys’ superb, old school rap NYC-style (and themed) “To The Five Boroughs” (2004) satisfies my search for a #5-themed concept album/song. No track has that title, so I’m going with this one, “Triple Trouble” (song 3; day 3 of Freezermas… c’mon this is all just an excuse for me to talk about music I like and celebrate the concept album/freezers anyway!), as an introduction to a collaborative cat (felid) project we’ve started; and to continue the felid theme from Sunday (also be sure to check out the Snow Leopard dissection I posted on earlier!):

If You If You 
Wanna Know Wanna Know 
The real deal about the cats
Well let me tell you 
We’re felid funded ya’ll 
We’re gonna bring you some mad facts

(yes, that’s painful, I know… be relieved, I tried working some rap jargon into this post’s text but it just looked wack)

Dodgy-looking bagged-up skinned jaguar (bag-uar?) after delivery from Scotland.

Dodgy-looking bagged-up skinned jaguar (bag-uar?) after delivery from Scotland.

Anjali Goswami at University College London, myself, and Stephanie Pierce have teamed up to join the former’s skills in mammalian evolution, morphometrics, evo-devo and more together with our RVC team’s talents in biomechanics, evolution and modelling, and to apply them to resolving some key questions in felid evolution. We’ve hired a great postdoc from Bristol’s PhD programme, soon-to-be-Dr. Andrew Cuff, to do a lot of the experimental/modelling work, and then we have the marvellous Marcela Randau as a PhD student to tackle more of the morphometrics/evo-devo questions, which we’ll then tie together, as our Leverhulme Trust grant’s abstract explains:

“In studying the evolution of vertebrate locomotion, the focus for centuries has been on limb evolution. Despite significant evolutionary and developmental correlations among the limbs, vertebrae, and girdles, no biomechanical studies have examined the entire postcranial skeleton or explicitly considered the genetic and developmental processes that underly morphological variation, which are captured in phenotypic correlations. We propose to conduct experimental and geometric morphometric analyses of living and fossil cats, including the only large, crouching mammals, to study the evolution of locomotion, the mechanical consequences of size-related morphological evolution, and the evolution of correlations (modularity) in the postcranial musculoskeletal system.”

Above: snow leopard (headless) reconstructed and taken for a spin

Our study will integrate some prior studies from Anjali’s group, on modularity for example, and from my group, on the apparent lack of postural change with increasing size in felids (most other birds and mammals get more straight-legged as size increases, to aid in support, cats don’t– paper forthcoming). How does the neglected vertebral column fit into these limb-focused ideas? We’ll find out!

And it’s all very freezer-based research, using a growing stock of specimens that we’ve collected from zoo/park mortalities, many of which are kindly being supplied by Dr. Andrew Kitchener from the National Museums Scotland. We’ll be scanning, dissecting, measuring and modelling them and then returning the skeletons to be curated as museum specimens. This page features five sets of felid specimens involved in the research. We’ll be presenting plenty more about this research on this blog and elsewhere as it continues!

Above: ocelot from Freezermas day 1, now in 3D!

The Bag-o-Cats: whole specimens of a black-footed cat (Felis nigripes), juvenile cheetah, and juvenile snow leopard. I think. Sometimes you get a bag-o-cats and are not sure.

The Bag-o-Cats: x-ray CT slice showing whole specimens of a black-footed cat (Felis nigripes), juvenile cheetah, and juvenile snow leopard. I think. Sometimes you get a bag-o-cats and are not sure.

Panthera atrox (large American lion) from the NHM in LA. Oh yes we'll be applying our insights to strange extinct cats, too!

Panthera atrox (large American lion; “Naegele’s giant jaguar”) from the NHM in LA. Oh yes we’ll be applying our insights to strange extinct cats, too!

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Freezermas continues! Today we have a treat for you. Lots of detailed anatomy! This post comes from my team’s dissections of an ostrich last week (~3-7 February 2014), which I’ve been tweeting about as part of a larger project called the Open Ostrich.

However, before I go further, it’s as important as ever to note this:

Stomach-Churning Rating: 9/10: bloody pictures of a dissection of a large ostrich follow. Head to toes, it gets messy. Just be glad it wasn’t rotten; I was glad. Not Safe For Lunch!

If the introductory picture below gets the butterflies a-fluttering in your tummy, turn back now! It gets messier. There are tamer pics in my earlier Naked Ostriches post (still, a rating of 6/10 or so for stomach-churning-ness there).

All photo credits  (used with permission) on this post go to palaeoartist Bob Nicholls (please check out his website!), who got to attend and get hands-on experience in extant dinosaur anatomy with my team and Writtle College lecturer Nieky VanVeggel (more from Nieky soon)!

Research Fellow Jeff Rankin, myself and technician/MRes student Kyle Chadwick get to work.

Research Fellow Jeff Rankin, myself and technician/MRes student Kyle Chadwick get to work, removing a wing.

This is a male ostrich, 71.3 kg in body mass, that had gone lame in one foot last summer and, for welfare reasons, we had to put down for a local farmer, then we got the body to study. We took advantage of a bad situation; the animal was better off being humanely put down.

The number for today is 6; six posts left in Freezermas. But I had no idea I’d have a hard time finding a song involving 6, from a concept album. Yet 6 three times over is Slayer’s numerus operandi, and so… The concept album for today is Slayer’s  1986 thematic opus “Reign in Blood” (a pivotal album for speed/death metal). The most appropriate track here is the plodding, pounding, brooding, then savagely furious “Postmortem“, which leads (literally and figuratively, in thunderous fashion) to the madness of the title track, after Tom Araya barks the final verse:

“The waves of blood are rushing near, pounding at the walls of lies

Turning off my sanity, reaching back into my mind

Non-rising body from the grave showing new reality

What I am, what I want, I’m only after death”

I’m not going to try to reword those morbid lyrics into something humorous and fitting the ostrich theme of this post. I’ll stick with a serious tone for now. I like to take these opportunities to provoke thought about the duality of a situation like this. It’s grim stuff; dark and bloody and saturated with our own inner fears of mortality and our disgust at what normally is politely concealed behind the integumentary system’s viscoelastic walls of keratin and collagen.

But it’s also profoundly beautiful stuff– anatomy, even in a gory state like this, has a mesmerizing impact: how intricately the varied parts fit together with each other and with their roles in their environment, or even the richness of hues and multifarous patterns that pervade the dissected form, or the surprising variations within an individual that tell you stories about its life, health or growth. Every dissection is a new journey for an anatomist.

OK I’ve given you enough time to gird yourself; into the Open Ostrich we go! The remainder is a photo-blog exploration of ostrich gross anatomy, from our detailed postmortem.

(more…)

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Seven dead old limbs
Seven science wins
Seven icy forms beheld
And our trip begins

Seven anat’my jokes
Seven bloody posts
Seven are our sci-comm fires
Seven frozen choirs…

(props to Iron Maiden’s “Moonchild” opening lyrics, from the iconic “Seventh Son of a Seventh Son” concept album, of lofty, epic, frozen, anatomy-bearing motifs)

7th Son

So we come full circle to another Freezermas, another foolhardy attempt to honour Charles Darwin (his birthday is Weds 12th Feb) with seven blog posts in seven days!

There will be mysterious morphology! Expositions of new projects and a new paper! Detailed dissections showing amazing anatomy! Silly songs and other nonsense! So much more that I have no idea about at this writing but will surely come to me! (there is an amorphous plan)

Last year I invoked the 7 days of Freezermas song, but this year the songcraft has changed. Christmas is so 2013! Time for a 1970smodern approach! We’re doing hard rock/heavy metal concept album songs and motifs each day. I started off with one above. Future posts will try to stick to a theme of songs/albums featuring numbers, counting down from seven. Because we all know that Darwin loved to rock. But let’s get on with the real rockin': the freezer-based anatomical science!

Today we’ll ease you in to Freezermas: The Concept Album, like the acoustic intro of Moonchild did, with some simple Mystery CT Anatomy…

(insert guitar solo here while you mentally prepare yourself)

Stomach-Churning Rating: 2/10; simple CT scan of a body.

Mystery Anatomy 2014: same rules as before; remember that the scoreboard has been reset.

Identify the animal in the CT scout/pilot image below, as specifically as you can. 

Today’s special rule: Your answer must be in the form of a lyric (at least 2 lines) from a song by Queen (Google some if you’re unfamiliar– but how?).

Why Queen? One should never question Queen; not a little or a lot.

Difficulty: Is this the real life? Is this just fantasy?

You will probably want to click to emgiganticate the image below.

Mystery CT 11

Don’t let this one drive you Stone Cold Crazy! I know you’re feeling Under Pressure; just Tie Your Mother Down and play The Game.

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…a daily picture of anatomy! And today the pictures are a mysteryyyyyyy! ♫

Welcome back againagain, and again (gasp, pant)– and again (exhausted howl)… and… aaaaaagaiiiiin… to Freezermas

This is the end. I’ve worked hard all week to bring you all-new content for Freezermas, and on the Seventh Day I get drunk rest– and make you do the work! Off into the hoary wilderness you go, seeking answers to eternal trivial mysteries.

Seven mystery photos of museum specimens today, each from a different museum (or other institution whose role it is to display critters, in 2/7 cases) and animal! I’ve visited all these facilities and taken these photos myself. Which specimens can you identify, and (ultra difficult) can you identify the institution it’s from?

Stomach-Churning Rating: 2/10. Super tame.

You had some impromptu practice on day 2. Very well, then. This session counts for points. If you want a recap of points, see last Mystery Dissection.

But because the pictures are small and numerous (refer to them by number 1-7, please), the points/correct answer are simplified: 2 pts for correct answer, and maybe 1 bonus pt for something clever but incorrect, 0 pts here just for shooting the breeze (“Superhuman effort isn’t worth a damn unless it achieves results.”–Ernest Shackleton), plus 1 pt extra credit if you correctly ID the museum/institution. Being first does not matter here. Just being correct. With 7 mysteries, you can freeze up a lot of points here! But…

Difficulty: Cropping. Lots of cropping. And therefore quite pixellated if you zoom in much; don’t even bother clicking to embigitate. However, there may or may not be themes between some pictures, or critical clues. They are identifiable.

Off you venture, brave Freezerinos! Wear multiple layers.

1) Freezermas7-1 2) Freezermas7-2

3) Freezermas7-3

4) Freezermas7-4 

5)Freezermas7-5 6)Freezermas7-6

7)Freezermas7-7

But wait– there is a mystery eighth specimen, which even I am not completely sure what it is! No points for figuring it out, but mucho respect!

Freezermas-MysteryXtra

And…

Happy Freezermas! One last time– sing it: “On the seventh day of Freezermas, this blo-og gave to me: one tibiotarsustwo silly Darwinsthree muscle layersfour gory heartsfive doggie models, six mangled pangl’ins a-aaaaaaand seven specimens that are mysteries!” ♪

I hope you enjoyed Freezermas. Let’s hope we’re all thawed out in time for the next one.


CLUES/ANSWERS: Click these thumbnails to embigrinate them if you need help–

snapperpareiasaurs frogfish  Sclerocephalus  Suedinosauroidaardvarks

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…a daily picture of anatomy! And today it is five pictures; zza-zza-zee! ♫

Welcome back againagain, (gasp, pant) and again to Freezermas

I’m letting the dogs out today. Science gone barking mad! Hopefully my puns will not screw the pooch.

Stomach-Churning Rating: 4/10; a dog cadaver’s leg (not messy), then just tame digital images of anatomy.

I am working with Rich Ellis, a former MSc student at Univ. Colorado (see his cool new paper here!), for a fun new collaboration this year. He was awarded a prestigious Whitaker Foundation scholarship to do this research, which focuses on how different animals stand up from a squatting position, with the legs about as bent as they can be.

We want to know how animals do this standing up movement, because it is in some ways a very demanding activity. Very flexed/bent limb joints mean that the muscles (and some tendons) are stretched about as far as they ever will be. So this places them at disadvantageous lengths (and leverage, or mechanical advantage) for producing force. We know almost nothing about how any animal, even humans, does this-- how close to their limits of length are their muscles? Which muscles are closest? Does this change in animals with different numbers of legs, postures, anatomy, size, etc? Such fundamental questions are totally unaddressed. It’s an exciting area to blaze a new trail in, as Rich is doing. So far, we’ve worked with quail, humans, and now greyhounds; in the past I did some simple studies with horses and elephants, too. Jeff Rankin from my team and other collaborators have also worked on six species of birds, of varying sizes, to see how their squat-stand mechanics change.  Thus we’ve covered a wide diversity of animals, and now we’re learning from that diversity. “Diversity enables discovery,” one of my former PhD mentors Prof. Bob Full always says. Too true.

Greyhounds are interesting because they are medium-sized, long-legged, quadrupedal, quite erect in posture, and very specialized for fast running. Fast runners tend to have big muscles with fairly short fibres. Short fibres are bad for moving the joints through very large ranges of motion. So how does a greyhound stand up? Obviously they can do it, but they might have some interesting strategies for doing so- the demands for large joint motion may require a compromise with the demands for fast running. Or maybe the two demands actually can both be optimized without conflict. We don’t know. But we’re going to find out, and then we’ll see how greyhounds compare with other animals.

To find out, we first have to measure some dogs standing up. We’ve done that for about 8 greyhounds. Here is an example of a cooperative pooch:

Those harmless experiments, if you follow me on Twitter, were live-tweeted under the hashtag #StandSpotStand… I dropped the ball there and didn’t continue the tweeting long after data collection, but we got the point across– it’s fun science addressing useful questions. Anyway, the experiments went well, thanks to cooperative pooches like the one above, and Rich has analyzed most of the data.

Now the next step involves the cadaver of a dog. We could anaesthetize our subjects and do this next procedure to obtain subject-specific anatomy. But it really wouldn’t be ethically justified (and if I were an owner I wouldn’t allow it either!) and so we don’t. A greyhound is a greyhound as far as we’re concerned; they’ll be more like each other than either is like a quail or a human. Individual variation is a whole other subject, and there are published data on this that we can compare with.

We get a dead dog’s leg — we don’t kill them; we get cadavers and re-use them:

Greyhound hindlimb for CT

We study the hindlimb because birds and humans don’t use their forelimbs much to stand up normally, so this makes comparisons simpler. We’re collecting forelimb data, though, as we work with quadrupeds, for a rainy day.

We then CT scan the leg, getting a stack of slices like this– see what you can identify here:

It’s not so clear in these images, but I was impressed to see that the muscles showed up very clearly with this leg. That was doggone cool! Perhaps some combination of formalin preservation, fresh condition, and freezing made the CT images clearer than I am used to. Anyway, this turned out to be a treat for our research, as follows.

We then use commercial software (we like Mimics; others use Amira or other packages) to “segment” (make digital representations in 3D) the CT scan data into 3D anatomy, partitioning the greyscale CT images into coloured individual objects– two views of one part of the thigh are shown below.

What can you identify as different colours here? There are lots of clues in the images (click to embiggen):

Hindlimb segmentation of greyhound

And here is what the whole thigh looks like when you switch to the 3D imaging view:

Quite fetching image, eh?!

The next steps after we finish the limb segmentation are to apply the experimental data we observed for greyhounds of comparable size by importing the model and those data into biomechanics software (SIMM/OpenSim). We’ve done about 40 models like this for various species. I detailed this procedure for an elephant here.

Then, at long last, science will know how a greyhound stands up! Wahoo! Waise the woof! Stay tuned as we hound you with more progress on this research-as-it-happens. Rich just finished the above thigh model this week, and the rest of the leg will be done soon.

Many thanks to Rich Ellis for providing images used here. And thank you for persevering my puns; they will now be cur tailed.

Happy Freezermas! Sing it: “On the fifth day of Freezermas, this blo-og gave to me: one tibiotarsus, two silly Darwins, three muscle layers, four gory hearts, a-and five stages modelling a doggie!” ♪

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