Press Release 09-147
Of Mutts and Men
Genetic study of African village dogs challenges the ancestral origins of several dog breeds
Watch the audio slideshow.
Credit and Larger Version
August 3, 2009
View an audio slideshow of researchers studying village dogs.
Domesticated animals provide man with benefits such as food, clothing and muscle power. Dogs, which descend from gray wolves that originated in Eurasia, were the first animals domesticated by man. Since that time, man has imposed a strong artificial selection pressure for desirable traits, resulting in the various dog breeds we have today.
A recent study published in the August 3 issue of Proceedings of the National Academy of Sciences provides insight into the origin of some popular breed dogs and how domestication has affected the overall level of diversity in dogs. Adam Boyko in the Department of Biological Statistics and Computational Biology at Cornell University is the lead author of the study.
Boyko is optimistic that this NSF-supported study will help refine the statistical models scientists currently used to understand evolution and genetic diversity. He stated, "How the domestication process affects genetic diversity is poorly understood. We were interested in studying village dogs because we expected them to be the modern day dogs most similar to dogs that existed before man began to create breeds. Our study is unique because we are able to surmise whether specific village dog populations are more genetically similar to breed dogs or indigenous ancestral dogs."
Mobility is another factor that affects genetic diversity of dogs. Because ancient dog populations have a location-specific genetic "signature," researchers can learn about migration patterns and population history by comparing the markers found in breed dogs to those observed in the semi-feral village dog populations of geographically isolated areas.
Boyko and his team, which includes his brother, sister-in-law, and a number of African research partners, sampled 318 village dogs from seven distinct regions of Africa. They compared the genetic signature of village dogs to Pharaoh hounds, Rhodesian ridgebacks and other breed dogs thought to be native to Africa, in addition to Puerto Rican street dogs and mixed breed dogs from the U.S.
They found that most African village dogs are genetically distinct from non-native breed dogs, but share some markers with mixed breed dogs from North America. These results indicate that African village dogs descend from indigenous ancestors related to Basenjis, while Pharaoh hounds and Rhodesian ridgebacks, previously believed to be African in origin, are more closely related to mixed-breed American dogs.
"For the most part, African dogs are distinct from other dogs we have studied, and these village dog populations display more diversity than purebred dogs across the markers we tested," explains Boyko. "We found exceptions in Namibia and Giza, which may be due to European colonization or proximity to Eurasia, the ancestral home of modern breed dogs."
The unique relationship between humans and dogs provides the opportunity to infer details about the ancient people that also inhabited the places in which these dogs lived. Using genetics to trace the movements of dog populations across continents will likely yield insights into the migrations of man during these periods. Therefore, the genetic history of man's best friend may also speak to the history and habits of man.
-NSF-
Friday, August 7, 2009
Sunday, August 2, 2009
Popularity of CAM in the U.S.
Despite skeptical outcry, Americans continue to utilize complementary and alternative practices, although the level of use may be plateauing....
"Approximately 38 percent of adults use some form of CAM for health and wellness or to treat a variety of diseases and conditions, according to data from the 2007 National Health Interview Survey (NHIS)....CAM accounts for approximately 1.5 percent of total health care expenditures ($2.2 trillion2) and 11.2 percent of total out-of-pocket expenditures (conventional out-of-pocket: $286.6 billion2 and CAM out-of-pocket: $33.9 billion1) on health care in the United States. "
Full story here:
http://www.medicalnewstoday.com/articles/159430.php
"Approximately 38 percent of adults use some form of CAM for health and wellness or to treat a variety of diseases and conditions, according to data from the 2007 National Health Interview Survey (NHIS)....CAM accounts for approximately 1.5 percent of total health care expenditures ($2.2 trillion2) and 11.2 percent of total out-of-pocket expenditures (conventional out-of-pocket: $286.6 billion2 and CAM out-of-pocket: $33.9 billion1) on health care in the United States. "
Full story here:
http://www.medicalnewstoday.com/articles/159430.php
Wednesday, July 22, 2009
liver shunts and proper diets
Congenital liver shunts are quite common in some breeds of dog - in the U.S., this is notably the yorkie. The proper terminology is "Portosystemic shunt" (PSS), and it denotes a situation where blood flow from the GI tract bypasses processing by the liver. This critical mistake means that protein particles absorbed from the GI tract are left untended by the gentle ministrations of the liver. The liver specializes in converting ammonia, a by-product of protein breakdown, into urea, which is less toxic and easily eliminated by the kidneys.
When ammonia accumulates in the blood, changes in neurotransmitters lead to brain dysfunction and the clinical manifestation ranges from simple lethargy to outright seizures. This condition is called hepatic encephalopathy or HE. For dogs with PSS, this is the limiting factor on quality of life and life expectancy, although the disease can be managed more or less with surgery or diet change (and often both).
It helps to restrict the protein in the diet, because that will lower overall ammonia levels. Some evidence also suggests that the *type* of protein influences the types of neurotransmitters orchestrating brain function. If aromatic amino acids predominate (more common in meat protein), the neurotransmitter balance will be tipped towards brain dysfunction.
This study compared the clinical results of feeding a low protein diet composed primarily of soy protein vs a low protein diet containing primarily poultry protein.
Dogs with PSS were fed first one of these diets, then the other, in blinded fashion so that neither the investigators nor the owners were aware of the diet being fed.
The study showed that both diets reduced signs of encephalopathy, which might be expected when reducing overall protein content. Interestingly, when dogs were eating the soy-based diet, ammonia levels were significantly reduced. In addition, these dogs had better blood coagulation capacity. [When the liver fails, the clotting factors normally produced are decreased, leading to possible bleeding episodes). This improved clotting capacity, along with an increase in another protein made by the liver, suggests that the soy-based diet actually enhances the liver's capacity to function.
The results of this study may be particularly important to owners considering shunt surgery for their dogs. Elevated ammonia levels (with the associated changes in brain neurotransmitter levels) mean that anesthesia is a bigger risk in these dogs than in normal dogs of the same age. And if clotting is immpaired, surgery could lead to uncontrolled bleeding.
So the study is *really* interesting because it suggests that feeding a low protein soy based diet BEFORE surgery could reduce the risk surgery presents. Nice.
Proot S, Biourge V, Teske E, Rothuizen J. Soy protein isolate vs meat-based low protein diet for dogs congenital portosystemic shunts. J Vet Intern Med 2009;23:794
When ammonia accumulates in the blood, changes in neurotransmitters lead to brain dysfunction and the clinical manifestation ranges from simple lethargy to outright seizures. This condition is called hepatic encephalopathy or HE. For dogs with PSS, this is the limiting factor on quality of life and life expectancy, although the disease can be managed more or less with surgery or diet change (and often both).
It helps to restrict the protein in the diet, because that will lower overall ammonia levels. Some evidence also suggests that the *type* of protein influences the types of neurotransmitters orchestrating brain function. If aromatic amino acids predominate (more common in meat protein), the neurotransmitter balance will be tipped towards brain dysfunction.
This study compared the clinical results of feeding a low protein diet composed primarily of soy protein vs a low protein diet containing primarily poultry protein.
Dogs with PSS were fed first one of these diets, then the other, in blinded fashion so that neither the investigators nor the owners were aware of the diet being fed.
The study showed that both diets reduced signs of encephalopathy, which might be expected when reducing overall protein content. Interestingly, when dogs were eating the soy-based diet, ammonia levels were significantly reduced. In addition, these dogs had better blood coagulation capacity. [When the liver fails, the clotting factors normally produced are decreased, leading to possible bleeding episodes). This improved clotting capacity, along with an increase in another protein made by the liver, suggests that the soy-based diet actually enhances the liver's capacity to function.
The results of this study may be particularly important to owners considering shunt surgery for their dogs. Elevated ammonia levels (with the associated changes in brain neurotransmitter levels) mean that anesthesia is a bigger risk in these dogs than in normal dogs of the same age. And if clotting is immpaired, surgery could lead to uncontrolled bleeding.
So the study is *really* interesting because it suggests that feeding a low protein soy based diet BEFORE surgery could reduce the risk surgery presents. Nice.
Proot S, Biourge V, Teske E, Rothuizen J. Soy protein isolate vs meat-based low protein diet for dogs congenital portosystemic shunts. J Vet Intern Med 2009;23:794
Friday, July 17, 2009
More web claptrap from pet nutrition expert
From: http://www.examiner.com/x-12702-Pittsburgh-Animal-Health-Examiner~y2009m6d24-7-reasons-dogs-and-cats-should-not-get-table-scraps-or-eat-people-food
7 reasons dogs and cats should not get table scraps or eat people food
1. Giving pets table scraps supplements their diets with unnecessary calories. Animals depend on the nutrients found in food specially formulated for them. If they eat people food, they will eat less of their own food and miss out on adequate nutrition.
COMMENTS FROM DR. WYNN: There are really two different issues. Yes, most dogs and cats eat formulated foods, designed to provide complete nutrition. If you provide a lot of some other, non balanced food, it could cause very real deficiencies. But this one irks me – “Giving pets table scraps supplements their diets with unnecessary calories”. Well, yeah, if you assume people are giving junk food, pure meat and cheese, etc. But let’s try to parse this out for the majority of people who are capable of understanding the difference between veggies/fruits and everything else. How about a better sweeping statement, that goes like this: “Giving pets table scraps supplements their diets with unnecessary calories, unless the scraps consist primarily of fresh veggies and fruits”.
2. Animals who eat their normal amount of pet food in addition to the extra calories in table scraps can easily gain weight. Obesity puts animals at risk for health problems.
COMMENTS: see #1
3. Receiving table scraps or people food encourages unhealthy food behaviors. It can cause food aggression in both cats and dogs, and it encourages begging at the table.
COMMENTS: Ok, help people understand how to give fresh foods in the bowl at mealtime, or as a reward for a requested behavior.
4. Some food is toxic to cats. Cats are carnivorous and cannot digest many vegetables or starch. Franny Syufy from About.com reminds pet owners that “...may have forgotten that the gravy slathered over your Thanksgiving turkey used broth that was flavored with onion, among other things. While it is tasty and harmless to humans, onions are very toxic to cats.” In her article titled “Human Foods for Cats?” Syufy lists onions, garlic, green tomatoes, raw potatoes, root vegetables, chocolate, grapes and raisins, and milk as food especially toxic to cats. (If the cats insist on drinking milk, they should drink lactose free milk such as CatSip, which can be purchased at most pet stores.)
COMMENTS: milk toxic to cats? Are you kidding me? OK, some cats might not tolerate it, like humans with lactose intolerance, but toxic? And what on earth is she talking about with root vegetables being toxic? Ok, onions are toxic, but sweet potatos? Burdock? Perhaps we need better sources for our information than About.com?
5. Some foods are toxic to dogs, such as chocolate in large quantities, and dairy products. Onions can also be poisonous to dogs so pet owners should be aware of the ingredients in anything they feed to animals (even onion powder can have adverse effects on pets.) Fatty foods can lead to pancreatitis, and excessive levels of sugar can lead to obesity and diabetes.
OK, I’ll support this except that I still don’t think that lactose intolerance is in the same class with toxicity.
6. Animals cannot digest all food. Corn and sugar are especially tough on animals' digestive systems. Potatoes, lunch meat, and condiments often have high sugar contents.
COMMENT: I’m not sure what this means – corn and sugar are tough on digestive systems? Sugar is highly digestible, but lots of it will lead to metabolic problems. Corn – it’s not digestible if given as whole kernels because none of us break down that cellulose kernel coat very well. But it’s digestible if processed either by human teeth (dogs don’t spend a lot of time chewing), a food processor, or in dog food factories. Do we want a corn-BASED diet? No, but let’s try more precision when we talk about the effect corn has on digestive systems.
7. Any meat product containing bones can break and puncture the throat, stomach, or intestines, or cause constipation by actually blocking the digestive path. Even if bones do not cause an injury, they are sure to cause discomfort. Crushed bones or very frail bones typically do not cause problems. (If the dog insists on getting the bone from the roast, monitor the dog and remove the bone once it breaks or becomes small enough to be a choking hazard.)
COMMENT: I’ll go with this. By the way, I’ve never found authoritative support for the raw feeding claim that cooked bones are more brittle than raw ones. I can see how it might be true but I’ve never seen a good explanation. Has anyone else?
Likewise, dogs receive too much protein from cat food, and dog food lacks important nutrients like taurine for cats. There's a reason these foods are labeled for what they are. The best way to ensure animals get adequate nutrition is to find a quality pet food they enjoy and stay consistent.
COMMENT: Cat foods do not supply too much protein to dogs. Protein is not toxic unless you have severe kidney disease. What cat foods do provide along with all that meat is a high fat level, and that can lead to diarrhea and/or pancreatitis. But there is no doubt that cats can die from eating dog food – which I’ve seen happen when food is left down for the dog free choice – yet another reason not to do that!
7 reasons dogs and cats should not get table scraps or eat people food
1. Giving pets table scraps supplements their diets with unnecessary calories. Animals depend on the nutrients found in food specially formulated for them. If they eat people food, they will eat less of their own food and miss out on adequate nutrition.
COMMENTS FROM DR. WYNN: There are really two different issues. Yes, most dogs and cats eat formulated foods, designed to provide complete nutrition. If you provide a lot of some other, non balanced food, it could cause very real deficiencies. But this one irks me – “Giving pets table scraps supplements their diets with unnecessary calories”. Well, yeah, if you assume people are giving junk food, pure meat and cheese, etc. But let’s try to parse this out for the majority of people who are capable of understanding the difference between veggies/fruits and everything else. How about a better sweeping statement, that goes like this: “Giving pets table scraps supplements their diets with unnecessary calories, unless the scraps consist primarily of fresh veggies and fruits”.
2. Animals who eat their normal amount of pet food in addition to the extra calories in table scraps can easily gain weight. Obesity puts animals at risk for health problems.
COMMENTS: see #1
3. Receiving table scraps or people food encourages unhealthy food behaviors. It can cause food aggression in both cats and dogs, and it encourages begging at the table.
COMMENTS: Ok, help people understand how to give fresh foods in the bowl at mealtime, or as a reward for a requested behavior.
4. Some food is toxic to cats. Cats are carnivorous and cannot digest many vegetables or starch. Franny Syufy from About.com reminds pet owners that “...may have forgotten that the gravy slathered over your Thanksgiving turkey used broth that was flavored with onion, among other things. While it is tasty and harmless to humans, onions are very toxic to cats.” In her article titled “Human Foods for Cats?” Syufy lists onions, garlic, green tomatoes, raw potatoes, root vegetables, chocolate, grapes and raisins, and milk as food especially toxic to cats. (If the cats insist on drinking milk, they should drink lactose free milk such as CatSip, which can be purchased at most pet stores.)
COMMENTS: milk toxic to cats? Are you kidding me? OK, some cats might not tolerate it, like humans with lactose intolerance, but toxic? And what on earth is she talking about with root vegetables being toxic? Ok, onions are toxic, but sweet potatos? Burdock? Perhaps we need better sources for our information than About.com?
5. Some foods are toxic to dogs, such as chocolate in large quantities, and dairy products. Onions can also be poisonous to dogs so pet owners should be aware of the ingredients in anything they feed to animals (even onion powder can have adverse effects on pets.) Fatty foods can lead to pancreatitis, and excessive levels of sugar can lead to obesity and diabetes.
OK, I’ll support this except that I still don’t think that lactose intolerance is in the same class with toxicity.
6. Animals cannot digest all food. Corn and sugar are especially tough on animals' digestive systems. Potatoes, lunch meat, and condiments often have high sugar contents.
COMMENT: I’m not sure what this means – corn and sugar are tough on digestive systems? Sugar is highly digestible, but lots of it will lead to metabolic problems. Corn – it’s not digestible if given as whole kernels because none of us break down that cellulose kernel coat very well. But it’s digestible if processed either by human teeth (dogs don’t spend a lot of time chewing), a food processor, or in dog food factories. Do we want a corn-BASED diet? No, but let’s try more precision when we talk about the effect corn has on digestive systems.
7. Any meat product containing bones can break and puncture the throat, stomach, or intestines, or cause constipation by actually blocking the digestive path. Even if bones do not cause an injury, they are sure to cause discomfort. Crushed bones or very frail bones typically do not cause problems. (If the dog insists on getting the bone from the roast, monitor the dog and remove the bone once it breaks or becomes small enough to be a choking hazard.)
COMMENT: I’ll go with this. By the way, I’ve never found authoritative support for the raw feeding claim that cooked bones are more brittle than raw ones. I can see how it might be true but I’ve never seen a good explanation. Has anyone else?
Likewise, dogs receive too much protein from cat food, and dog food lacks important nutrients like taurine for cats. There's a reason these foods are labeled for what they are. The best way to ensure animals get adequate nutrition is to find a quality pet food they enjoy and stay consistent.
COMMENT: Cat foods do not supply too much protein to dogs. Protein is not toxic unless you have severe kidney disease. What cat foods do provide along with all that meat is a high fat level, and that can lead to diarrhea and/or pancreatitis. But there is no doubt that cats can die from eating dog food – which I’ve seen happen when food is left down for the dog free choice – yet another reason not to do that!
Sunday, July 12, 2009
This is a picture of the lines for 2 restaurants at the Seattle airport. The sign on your left denotes an asian restaurant with sushi, salads, and udon. The one on the right is, well, a popular American fast food joint.
See the lady in the salmon shirt? She is at the end of the line for sushi place - maybe 7-8 people at most. See the line behind her for the burger place? Add another 50% and you'll know how long it was.
What is WRONG with us?
Tuesday, July 7, 2009
Pet glucosamine products fail
If you're not already familiar with the work of ConsumerLab, you should get to know them and consider forking over the very reasonable subscription fee. They regularly quality test nutraceutical and herbal supplements and have reported some pretty startling results, such as lead contamination in common pet multivitamin products (http://www.consumerlab.com/reviews/multivitamin_multimineral_supplements/multivitamins/) and mold in a probiotic product (http://www.consumerlab.com/reviews/Probiotic_Supplements_Including_Lactobacillus_acidophilus_Bifidobacterium_and_Others/Probiotics/#results). The manufacturers generally responded with reasons why the testing was inaccurate or irrelevant. Whatever. But please note that by the time the dust settled, those manufacturers likely corrected those problems, so you can view negative ConsumerLab reports as wake-up calls.
The most recent is an updated review of glucosamine/chondroitin products for people and pets. Most of the products (including Cosequin which had been found to have deficiencies in a previous review) tested fine.
4 pet products did not past muster, however. One product contained only 6% of the claimed glucosamine and 15.9% of the claimed chondroitin. Not to mention that each treat only claimed to have 13.6 mg of glucosamine, which is enough to treat a 1 lb pet daily.
Another contained only 17% of the claimed chondroitin. A third product contained only 15.9% of claimed chondroitin. Another contained only 5.4% of claimed chondroitin.
I note that at least 3 of the companies with approved products are members of the National Animal Supplement Council (www.nasc.cc). None of the non-approved products come from NASC members. I'm just sayin.....
ADDENDUM: I posted the names of the products that failed and passed, but heard from ConsumerLab that those results are copyrighted. They wrote that posting these products publicly impacts their ability to collect subscription fees and conduct research. I understand that and have removed their names, and would again encourage everyone to subscribe - the rate is about $30/year and you would be pretty surprised at what you'll learn about over the counter products that you might think are good quality!
Sunday, July 5, 2009
I'm a wild foodie
I'm posting this picture of a wild foods dinner I attended a couple of weeks ago - freshly harvested daylily (stuffed with saffron rice), wild greens, and some roasted burdock root. And that was just the first course- you should have tasted the rosehip shortbread and elderberry sorbet for dessert! If you get a chance to attend a wild foods dinner with Patricia Kyritsi Howell near Clayton GA, do it!
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