Study: Starch Digestion Adaptation in Dogs

Discussion in 'Dogs - General Dog Chat' started by Shai, Jan 23, 2013.

  1. sassafras

    sassafras mushinois

    Joined:
    Feb 26, 2011
    Messages:
    6,405
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Minnesota
    But at what point does adapting to a particular component of a diet change that component from sub-par to being considered part of the normal, healthy diet? At some point in the distant past eucalyptus leaves were probably the subpar food source, but try feeding a koala bear anything else.

    That's obviously an extreme example, but... the point stands. I think what this study opens the door to demonstrating is that there are probably a lot more foods that are "healthy" for dogs and they really are more generalist than many people have been previously willing to consider.


    What I would really, REALLY love to see someday is someone doing something similar to this but comparing different individuals to one another and trying to correlate results to those individuals' tolerance of different types of food. Hopefully it will be done in my lifetime.
     
  2. SaraB

    SaraB New Member

    Joined:
    Mar 31, 2011
    Messages:
    5,798
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    St. Louis, MO
    This. Until someone proves that starches aren't good for dogs who evolved eating a large variety of food, I'm going to feed them as much of a variety as I can. Obviously still a meat based diet though, LOL.
     
  3. sassafras

    sassafras mushinois

    Joined:
    Feb 26, 2011
    Messages:
    6,405
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Minnesota
    Yea, it's not like anyone is saying ALL GRAINS, ALL THE TIME, ALL DOGSSSSS!!!!! based on this (very preliminary) research.

    I'm just mostly excited that someone, somewhere is actually trying to approach the question of diet in dogs in any kind of scientific, research-based manner at all. :p
     
  4. SaraB

    SaraB New Member

    Joined:
    Mar 31, 2011
    Messages:
    5,798
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    St. Louis, MO
    Agreeed!!! AND it's not funded by Purina.
     
  5. Pops2

    Pops2 New Member

    Joined:
    Sep 21, 2008
    Messages:
    3,072
    Likes Received:
    0
    Trophy Points:
    0
    Occupation:
    none
    Location:
    UT
    I am not convinced. There are enough defects (like square cube LAW deficiencies and the second law of thermodynamics) that the scientific community still officially calls it a THEORY. My biggest concern is that, according to the theory, two animals of one species can gain or lose chromosomes to become a new species. The problem with this is that, throughout the animal kingdom the spontaneous gain or loss of a chromosome is almost universally a survival disadvantage. For example Corky the Down syndrome kid from the 80s TV show, wonderful human being but clearly NOT a survival advantage in a precivilization fang and claw environment. Not single breeding experiment has ever produced a new species from within a species. All new artificial species have come from crossing existing species (in higher animals) or from gene splicing in lower animals.
    Further the assertion that dogs came from wolves would in fact make them wolves but current research shows only 98.6-98.8 % genetic commonality (coincidentally humans and chimps have 98.8% commonality). That is there is over 1% of genes that exist in one but not the other. Likewise dogs and coyotes have 98% commonality but wolves and coyotes only have 96% commonality. Dogs have an "elasticity" to their genes that so far hasn't been found in wolves. Oh and wolves from the ice age are on the species level genetically identical to modern greys. So yeah not at all convinced that dogs evolved from wolves. A common ancestor, MAYBE, but not FROM wolves.
     
  6. Shai

    Shai & the Muttly Crew

    Joined:
    Dec 14, 2009
    Messages:
    6,215
    Likes Received:
    0
    Trophy Points:
    0
    Do you know what the scientific definition of a theory is?
     
  7. Pops2

    Pops2 New Member

    Joined:
    Sep 21, 2008
    Messages:
    3,072
    Likes Received:
    0
    Trophy Points:
    0
    Occupation:
    none
    Location:
    UT
    Actually gravity is proven law. Newtons law of gravitation to be specific.
     
  8. Shai

    Shai & the Muttly Crew

    Joined:
    Dec 14, 2009
    Messages:
    6,215
    Likes Received:
    0
    Trophy Points:
    0
    Just for fun.

    http://www.talkorigins.org/faqs/evolution-fact.html

    Evolution is a Fact and a Theory
    by Laurence Moran
    Copyright © 1993-2002

    When non-biologists talk about biological evolution they often confuse two different aspects of the definition. On the one hand there is the question of whether or not modern organisms have evolved from older ancestral organisms or whether modern species are continuing to change over time. On the other hand there are questions about the mechanism of the observed changes... how did evolution occur? Biologists consider the existence of biological evolution to be a fact. It can be demonstrated today and the historical evidence for its occurrence in the past is overwhelming. However, biologists readily admit that they are less certain of the exact mechanism of evolution; there are several theories of the mechanism of evolution. Stephen J. Gould has put this as well as anyone else:

    In the American vernacular, "theory" often means "imperfect fact"--part of a hierarchy of confidence running downhill from fact to theory to hypothesis to guess. Thus the power of the creationist argument: evolution is "only" a theory and intense debate now rages about many aspects of the theory. If evolution is worse than a fact, and scientists can't even make up their minds about the theory, then what confidence can we have in it? Indeed, President Reagan echoed this argument before an evangelical group in Dallas when he said (in what I devoutly hope was campaign rhetoric): "Well, it is a theory. It is a scientific theory only, and it has in recent years been challenged in the world of science--that is, not believed in the scientific community to be as infallible as it once was."

    Well evolution is a theory. It is also a fact. And facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world's data. Theories are structures of ideas that explain and interpret facts. Facts don't go away when scientists debate rival theories to explain them. Einstein's theory of gravitation replaced Newton's in this century, but apples didn't suspend themselves in midair, pending the outcome. And humans evolved from ape-like ancestors whether they did so by Darwin's proposed mechanism or by some other yet to be discovered.

    Moreover, "fact" doesn't mean "absolute certainty"; there ain't no such animal in an exciting and complex world. The final proofs of logic and mathematics flow deductively from stated premises and achieve certainty only because they are not about the empirical world. Evolutionists make no claim for perpetual truth, though creationists often do (and then attack us falsely for a style of argument that they themselves favor). In science "fact" can only mean "confirmed to such a degree that it would be perverse to withhold provisional consent." I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms.

    Evolutionists have been very clear about this distinction of fact and theory from the very beginning, if only because we have always acknowledged how far we are from completely understanding the mechanisms (theory) by which evolution (fact) occurred. Darwin continually emphasized the difference between his two great and separate accomplishments: establishing the fact of evolution, and proposing a theory--natural selection--to explain the mechanism of evolution.

    - Stephen J. Gould, " Evolution as Fact and Theory"; Discover, May 1981

    Gould is stating the prevailing view of the scientific community. In other words, the experts on evolution consider it to be a fact. This is not an idea that originated with Gould as the following quotations indicate:

    Let me try to make crystal clear what is established beyond reasonable doubt, and what needs further study, about evolution. Evolution as a process that has always gone on in the history of the earth can be doubted only by those who are ignorant of the evidence or are resistant to evidence, owing to emotional blocks or to plain bigotry. By contrast, the mechanisms that bring evolution about certainly need study and clarification. There are no alternatives to evolution as history that can withstand critical examination. Yet we are constantly learning new and important facts about evolutionary mechanisms.

    - Theodosius Dobzhansky "Nothing in Biology Makes Sense Except in the Light of Evolution", American Biology Teacher vol. 35 (March 1973) reprinted in Evolution versus Creationism, J. Peter Zetterberg ed., ORYX Press, Phoenix AZ 1983

    Also:

    It is time for students of the evolutionary process, especially those who have been misquoted and used by the creationists, to state clearly that evolution is a fact, not theory, and that what is at issue within biology are questions of details of the process and the relative importance of different mechanisms of evolution. It is a fact that the earth with liquid water, is more than 3.6 billion years old. It is a fact that cellular life has been around for at least half of that period and that organized multicellular life is at least 800 million years old. It is a fact that major life forms now on earth were not at all represented in the past. There were no birds or mammals 250 million years ago. It is a fact that major life forms of the past are no longer living. There used to be dinosaurs and Pithecanthropus, and there are none now. It is a fact that all living forms come from previous living forms. Therefore, all present forms of life arose from ancestral forms that were different. Birds arose from nonbirds and humans from nonhumans. No person who pretends to any understanding of the natural world can deny these facts any more than she or he can deny that the earth is round, rotates on its axis, and revolves around the sun.

    The controversies about evolution lie in the realm of the relative importance of various forces in molding evolution.

    - R. C. Lewontin "Evolution/Creation Debate: A Time for Truth" Bioscience 31, 559 (1981) reprinted in Evolution versus Creationism, op cit.

    This concept is also explained in introductory biology books that are used in colleges and universities (and in some of the better high schools). For example, in some of the best such textbooks we find:

    Today, nearly all biologists acknowledge that evolution is a fact. The term theory is no longer appropriate except when referring to the various models that attempt to explain how life evolves... it is important to understand that the current questions about how life evolves in no way implies any disagreement over the fact of evolution.

    - Neil A. Campbell, Biology 2nd ed., 1990, Benjamin/Cummings, p. 434

    Also:

    Since Darwin's time, massive additional evidence has accumulated supporting the fact of evolution--that all living organisms present on earth today have arisen from earlier forms in the course of earth's long history. Indeed, all of modern biology is an affirmation of this relatedness of the many species of living things and of their gradual divergence from one another over the course of time. Since the publication of The Origin of Species, the important question, scientifically speaking, about evolution has not been whether it has taken place. That is no longer an issue among the vast majority of modern biologists. Today, the central and still fascinating questions for biologists concern the mechanisms by which evolution occurs.

    - Helena Curtis and N. Sue Barnes, Biology 5th ed. 1989, Worth Publishers, p. 972

    One of the best introductory books on evolution (as opposed to introductory biology) is that by Douglas J. Futuyma, and he makes the following comment:

    A few words need to be said about the "theory of evolution," which most people take to mean the proposition that organisms have evolved from common ancestors. In everyday speech, "theory" often means a hypothesis or even a mere speculation. But in science, "theory" means "a statement of what are held to be the general laws, principles, or causes of something known or observed." as the Oxford English Dictionary defines it. The theory of evolution is a body of interconnected statements about natural selection and the other processes that are thought to cause evolution, just as the atomic theory of chemistry and the Newtonian theory of mechanics are bodies of statements that describe causes of chemical and physical phenomena. In contrast, the statement that organisms have descended with modifications from common ancestors--the historical reality of evolution--is not a theory. It is a fact, as fully as the fact of the earth's revolution about the sun. Like the heliocentric solar system, evolution began as a hypothesis, and achieved "facthood" as the evidence in its favor became so strong that no knowledgeable and unbiased person could deny its reality. No biologist today would think of submitting a paper entitled "New evidence for evolution;" it simply has not been an issue for a century.

    - Douglas J. Futuyma, Evolutionary Biology, 2nd ed., 1986, Sinauer Associates, p. 15

    <more>
     
  9. Shai

    Shai & the Muttly Crew

    Joined:
    Dec 14, 2009
    Messages:
    6,215
    Likes Received:
    0
    Trophy Points:
    0
    <continued>
    There are readers of these newsgroups who reject evolution for religious reasons. In general these readers oppose both the fact of evolution and theories of mechanisms, although some anti-evolutionists have come to realize that there is a difference between the two concepts. That is why we see some leading anti-evolutionists admitting to the fact of "microevolution"--they know that evolution can be demonstrated. These readers will not be convinced of the "facthood" of (macro)evolution by any logical argument and it is a waste of time to make the attempt. The best that we can hope for is that they understand the argument that they oppose. Even this simple hope is rarely fulfilled.

    There are some readers who are not anti-evolutionist but still claim that evolution is "only" a theory which can't be proven. This group needs to distinguish between the fact that evolution occurs and the theory of the mechanism of evolution.

    We also need to distinguish between facts that are easy to demonstrate and those that are more circumstantial. Examples of evolution that are readily apparent include the fact that modern populations are evolving and the fact that two closely related species share a common ancestor. The evidence that Homo sapiens and chimpanzees share a recent common ancestor falls into this category. There is so much evidence in support of this aspect of primate evolution that it qualifies as a fact by any common definition of the word "fact."
    In other cases the available evidence is less strong. For example, the relationships of some of the major phyla are still being worked out. Also, the statement that all organisms have descended from a single common ancestor is strongly supported by the available evidence, and there is no opposing evidence. However, it is not yet appropriate to call this a "fact" since there are reasonable alternatives.

    Finally, there is an epistemological argument against evolution as fact. Some readers of these newsgroups point out that nothing in science can ever be "proven" and this includes evolution. According to this argument, the probability that evolution is the correct explanation of life as we know it may approach 99.9999...9% but it will never be 100%. Thus evolution cannot be a fact. This kind of argument might be appropriate in a philosophy class (it is essentially correct) but it won't do in the real world. A "fact," as Stephen J. Gould pointed out (see above), means something that is so highly probable that it would be silly not to accept it. This point has also been made by others who contest the nit-picking epistemologists.

    The honest scientist, like the philosopher, will tell you that nothing whatever can be or has been proved with fully 100% certainty, not even that you or I exist, nor anyone except himself, since he might be dreaming the whole thing. Thus there is no sharp line between speculation, hypothesis, theory, principle, and fact, but only a difference along a sliding scale, in the degree of probability of the idea. When we say a thing is a fact, then, we only mean that its probability is an extremely high one: so high that we are not bothered by doubt about it and are ready to act accordingly. Now in this use of the term fact, the only proper one, evolution is a fact. For the evidence in favor of it is as voluminous, diverse, and convincing as in the case of any other well established fact of science concerning the existence of things that cannot be directly seen, such as atoms, neutrons, or solar gravitation ....

    So enormous, ramifying, and consistent has the evidence for evolution become that if anyone could now disprove it, I should have my conception of the orderliness of the universe so shaken as to lead me to doubt even my own existence. If you like, then, I will grant you that in an absolute sense evolution is not a fact, or rather, that it is no more a fact than that you are hearing or reading these words.

    - H. J. Muller, "One Hundred Years Without Darwin Are Enough" School Science and Mathematics 59, 304-305. (1959) reprinted in Evolution versus Creationism op cit.

    In any meaningful sense evolution is a fact, but there are various theories concerning the mechanism of evolution.
     
  10. DenoLo

    DenoLo New Member

    Joined:
    Jun 4, 2012
    Messages:
    401
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    MA

    The scientific communities definition of "theory" is extremely different than the layman's definition. Theories can never be "proven". Laws and theories are also two completely different things-- theories don't become laws. In a very basic sense laws describe what happens and theories explain how/why they happen.
     
  11. Shai

    Shai & the Muttly Crew

    Joined:
    Dec 14, 2009
    Messages:
    6,215
    Likes Received:
    0
    Trophy Points:
    0
    Which is why (to expand) gravity is both a law and a theory. There is the law that two objects are attracted to one another, and the theory as to the mechanism by which that attraction occurs.

    ETA: That muddying is why I edited that earlier post -- figured it would just distract. Which it did, since I was too slow w/ the old edit.
     
  12. release the hounds

    release the hounds Active Member

    Joined:
    Apr 10, 2008
    Messages:
    4,381
    Likes Received:
    0
    Trophy Points:
    36
    Occupation:
    7
    Location:
    Midwest
    law, theory, fact, I don't really care. Sure my dogs can eat grains, so can I, doesn't mean we'll thrive off of them. In terms of nutrients and feeding our bodies what they need, I think they offer very little, especially by today's agri standards. All that protein and micronutrients that were once found in grains have been stripped away by modern methods. Grains to yield more starch, less "germ" and screw soil quality, we'll just use petro based fertilizers.

    Beyond that, my dogs will always eat what i've fed them. Meat based, varied and if I want to toss them a pizza crust cause I don't want it, there's no study that's going to make me do it or not do it :)
     
  13. Shai

    Shai & the Muttly Crew

    Joined:
    Dec 14, 2009
    Messages:
    6,215
    Likes Received:
    0
    Trophy Points:
    0
    The study doesn't try tell you what to feed your dog in any way shape or form. Feed your dog whatever works...that's always been the rule so far as I know.
     
  14. Flyinsbt

    Flyinsbt New Member

    Joined:
    Oct 6, 2012
    Messages:
    886
    Likes Received:
    0
    Trophy Points:
    0
    Occupation:
    3
    Location:
    Portland, OR
    Good points.

    What I find interesting in this study is just the simple proof that dogs have evolved different digestive capabilities than wolves. In discussions, I've often seen people assert that dogs must have the exact same digestion as wolves, and therefore must be fed a diet that exactly mirrors that of a wolf, for optimal health. And I've just never believed that dogs hadn't had time to evolve to different digestive capabilities. They've been domesticated a long time. And I really highly doubt that in that time, the majority of dogs have been fed a diet that doesn't contain starches. Their teeth are different, why not their digestive system?

    I think dogs are generalists, who can eat most things. There's a lot of variation in what is optimal, though. With my own dogs, I feed kibble. When I switched to a grain-free kibble, Tess seemed a bit better to me, so I feed grain free at this time. But Tully, who was her dam, showed no difference between grain free and grain included. So even with close relatives, there are differences in what they do well on.
     
  15. JacksonsMom

    JacksonsMom Active Member

    Joined:
    Nov 1, 2009
    Messages:
    8,693
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Maryland
    I think the study is important simply because it's a good start. It validates, to me, that calling dogs "obligate carnivores" isn't necessarily correct. I've seen lots of raw feeders who are just... so... "raw is the best diet for every canine!" And I have nothing against feeding a dog raw. I USED to be that way. I was very into the whole "a food must be THIS and that way" and "first five ingredient should be meat" and "NO grains". I've honestly done a 360 over the last year or so. For one, there are sooo many more important factors that go into a food than ingredients. 90% of foods out there are based solely on marketing and boy did it brainwash me.

    I've just always thought about how we've changed dogs so much from wolves -- not to mention, wolves in captivity can live as long as 20 years (eating not-so-amazing kibble). Wolves in the wild live 4-5 years on average. I'm not sure feeding our pet dogs like wolves is always in their best interest.

    Yes biologically I know they are essentially the same. Like said above, dogs have evolved alongside us from wolves. Selective breeding does a lot of funny things and I see no reason not to believe that some things have changed internally. Certain breeds are predisposed to such things as pancreatitis (Schanuzers, Yorkies, etc), some to other health issues. Sibes and GSDs are often known for somewhat sensitive stomachs. I also know that wolves were not being fed the way that most raw feeders feed their dog... they obviously weren't given meat from the grocery store that is most likely pumped full of grains and antibiotics anyways, but surely not as much time was being put into their meals. They weren't taken to the vet when things go wrong, they weren't sleeping indoors, or given the best possible care, or given antibiotics when infections set in, etc, etc, etc. Medical care for pets is a pretty new invention, too, but I'm certainly not going to reject it in a time of need. If our dogs were out in the wild, nature really could care less about anything living a long and healthy life... it's all about survival of the fittest and if you don't make it, oh well.

    Yes, kibble is a pretty new "invention" and I'm sure most dogs lived very well without it, but I highly doubt these dogs were eating PMR or the way we feed raw today. Humans that were probably living on hardly anything themselves were surely not giving up all their good food to the dogs... they got scraps (I've heard corn mush and other grains) to whatever they could hunt themselves. I've even heard people go as far as calling kibble "death nuggets" which I find insane.

    I'm not in any way saying feeding raw is bad. I think a lot of dogs do fantastic on it and that's GREAT. I love the idea of feeding raw and I'm happy it works so great for so many dogs. But I don't get the hate on kibble (not on here). Bottom line is that all dogs are individuals, and yes certain breeds are predisposed to things that others may not be, and what one dog may thrive on another may not...

    There is just way too many variables out there to say that "my dog lived a longer and healthier life eating x food" or "my dog died because of eating y food". So many other factors come into play. There are going to be raw fed dogs that die young and there are going to be kibble fed dogs that live a long time (and a healthy life at that) and vice versa. Obviously it's up to us as dog owners to decide what is best for our dogs and what works best for THEM.

    I went from being all for super high protein food, no grains, etc, and I've gone to a grain inclusive food with moderate protein. There is so much fancy wording going on in a lot of these new holistic foods with not a whole lot to back up their claims.

    But honestly, above all, I believe that vaccination schedules, when or if the dog is fixed, amounts of exercise, and breeding/genetics matter a whole lot more than food does anyway.
     
  16. Red.Apricot

    Red.Apricot Active Member

    Joined:
    Aug 28, 2011
    Messages:
    2,984
    Likes Received:
    2
    Trophy Points:
    38
    Location:
    Southern California
    I don't think any of those are defects--the theory of evolution is pretty comfortably established even with the second law of thermodynamics. :]

    There's a lot more to evolution than the addition or loss of a chromosome, too--that's really not even close to the most common way things change.

    Do you have any links about the relatedness of dogs and coyotes? That's fascinating.
     
  17. Pops2

    Pops2 New Member

    Joined:
    Sep 21, 2008
    Messages:
    3,072
    Likes Received:
    0
    Trophy Points:
    0
    Occupation:
    none
    Location:
    UT
    According to what you just posted, the definition is the same. An UNPROVEN or UNPROVABLE idea.
    A law OTH is proven & can be reproven.
     
  18. sassafras

    sassafras mushinois

    Joined:
    Feb 26, 2011
    Messages:
    6,405
    Likes Received:
    0
    Trophy Points:
    36
    Location:
    Minnesota
    No.

    This is a pretty good explanation of the differences.

    So is this. In particular,

    The real confusion between theories, laws, and hypotheses comes from this statement from the second link, I think: " 'Unfortunately, even some scientists often use the term "theory" in a more colloquial sense, when they really mean to say "hypothesis.' "
     
  19. Psyfalcon

    Psyfalcon Fishies!

    Joined:
    Jun 5, 2006
    Messages:
    2,434
    Likes Received:
    0
    Trophy Points:
    0
    Occupation:
    Dog, Dog, Cat, Fish
    Location:
    Oregon
    Now we have two hypotheses (and not theories). Anyone want to fund it?

    Dogs can digest grains better than wolves, they should be fed more grains than wolves.

    or

    Dogs can digest grains better than wolves, but still to a terribly useless degree, therefore don't feed grains.

    We've taken a bit of research into DNA, and have come up with new questions to ask based on that. Oddly, those questions usually take the form of statements before a scientist is done with the grant proposal ;)
     
  20. Dizzy

    Dizzy Sit! Good dog.

    Joined:
    Sep 14, 2005
    Messages:
    17,761
    Likes Received:
    1
    Trophy Points:
    36
    Occupation:
    Not enough.
    Location:
    Wales
    I guess it's interesting, but the sample size is miniscule really. Be interesting if someone carries the research further.

    Early days.
     

Share This Page