Canine genomic research provides clues to breed development, appearance, behavior and disease

By Kim Campbell Thornton

Andrews McMeel Syndication

Family lore says we have Cherokee and Choctaw ancestry, but genetic testing didn’t bear that out. My dog Gemma, however, can claim to be a New World dog whose genetic ancestry -- at least some of it -- goes back 10,000 or more years to the earliest dogs who migrated with their people to populate the Americas.

Gemma is half-Chihuahua, according to her canine DNA test results from Embark. A study published last month in the journal Cell Reports found that Chihuahuas were among a group of dogs with large amounts of DNA unlike that of other breeds. Those breeds included the American hairless terrier, Chinese crested (not actually from China, despite the name), Peruvian Inca orchid, rat terrier, toy fox terrier and Xoloitzcuintli (also known as the Mexican hairless). Archaeological evidence of an ancient canine subspecies existed, but this study marks the first living evidence of it in modern breeds.

“What we noticed is that there are groups of American dogs that separated somewhat from the European breeds,” says study co-author and dog geneticist Heidi Parker of the National Institutes of Health. “We’ve been looking for some kind of signature of the New World Dog, and these dogs have New World Dogs hidden in their genome.”

Scientists examined gene sequences from 1,346 dogs representing 161 modern breeds to assemble a canine evolutionary tree. It’s the largest and most diverse group of breeds studied to date and includes dogs from North America, Europe, Africa and Asia.

What’s the value of such a study? It has several purposes. For one, the map of dog breeds will likely help researchers identify disease-causing genes in both dogs and humans.

“Using all this data, you can follow the migration of disease alleles and predict where they are likely to pop up next, and that’s just so empowering for our field because a dog is such a great model for many human diseases,” says the study’s senior co-author and dog geneticist Elaine Ostrander of the NIH. “Every time there’s a disease gene found in dogs, it turns out to be important in people, too.”

One interesting finding was evidence of shared diseases across groups of dogs. For instance, collie eye anomaly (CEA) is a disease that affects development of the choroid in herding breeds such as the Australian shepherd, border collie, collie and Shetland sheepdog. But it also affects Nova Scotia duck tolling retrievers, which until this study were not known to share ancestry with herding breeds. The analysis showed that collies and Shetland sheepdogs were strong but undocumented contributors to the duck tollers' ancestry, making them the likely source of the CEA mutation in that breed.

The study also highlighted how the most ancient dog breeds evolved to perform certain roles. Humans likely began with certain types of dogs -- such as sleek, leggy dogs with strong prey drives for hunting and mid-size dogs for moving flocks -- and then further selected for specific physical traits. The cultural move from hunting to agriculture may have instigated the formation of breeds in multiple regions.

“I think that understanding that types go back a lot longer than breeds or just physical appearances do is something to really think about,” Parker says.

More than half the dog breeds in existence have yet to be sequenced. The researchers plan to keep collecting dog genomes -- often acquired from DNA samples provided by owners at dog shows -- to fill in the gaps.

Gemma? She’s lording it over our cavalier King Charles spaniels because her ancestry goes back farther than theirs.

Q&A

Teach good

chewing habits

Q: My 4-month-old Rhodesian Ridgeback puppy ate my sofa. Literally! What can I do? I can’t afford to buy much more new furniture. -- via Facebook

A: Congratulations -- you have a normal puppy! That’s the good news. The bad news is that without plenty of training and supervision, things can get worse before they get better. Puppies are hard-wired to explore their environment, and since their paws don’t have opposable thumbs, they use the next best thing: their sharp teeth.

But you don’t have to lose any more furniture. Chewing and scratching provide pets with exercise and mental stimulation, but they don’t have to be destructive -- at least not to anything other than their approved toys. Puppy kindergarten followed by advanced training, as well as plenty of interactive exercise and playtime, can help you teach your pup how to channel his chewing -- and his energy, in general -- into more productive and acceptable activities. Here are some tips.

-- Put his brain to work with puzzle toys that make him think. Some favorites are the Snuffle Mat and the Nina Ottosson Twister. Believe it or not, a good mental workout can leave him too tired to even think about eating your furniture.

-- Provide interesting and long-lasting chew toys. I like the Kong not only for durability but also for its “stuffability.” Load it up with peanut butter, baby carrots, kibble and other tasty treats, freeze it, and then let him go to work trying to get all the goodies out.

-- When you see your puppy chewing on something he shouldn’t, get his attention so he turns away from it, and then give him an acceptable chew toy. Praise him when you see him chewing on his toys; it’s important for him to learn what’s OK for him to chew as well as what he shouldn’t. -- Mikkel Becker

Do you have a pet question? Send it to askpetconnection@gmail.com or visit Facebook.com/DrMartyBecker.

THE BUZZ

Pet ownership,

spending rise

-- A new generation is in love with pets. Members of Generation Y, or millennials, have surpassed the baby boomers by 3 percentage points to account for 35 percent of all pet owners, according to the latest National Pet Owners Survey from American Pet Products Association. They make up more than half of reptile, small-animal and saltwater fish owners. In other survey results, the number of pet-owning households is up, from 79.7 million in 2015 to the current 84.6 million. That means 68 percent of American households now include a pet. Spending on pets, including veterinary care, increased to $66.75 billion.

-- Record-breaking animals? Guinness World Records has them. They keep tabs on everything from longest tail to loudest purr. Among the record holders are Merlin, a 13-year-old tuxedo cat whose purr registers 67.8 decibels -- as noisy as an air conditioner. Irish wolfhound Keon lays claim to the title “longest tail.” His measures just over 30 inches. Didga the cat can perform 24 tricks in the space of a minute, and Purin, a 9-year-old beagle, caught 14 balls with her paws in a minute’s time. And a blue-and-gold macaw named Skipper Blue can place 19 rings on a target in one minute.

-- Find out which pet parasites and diseases are of concern in your area at petsandparasites.org, the consumer page for the Companion Animal Parasite Council. It has maps for tick-borne diseases such as Lyme and ehrlichia; internal parasites, including hookworms and roundworms; giardia, a protozoan parasite that can affect dogs and humans; plus infectious diseases such as feline leukemia virus and feline immunodeficiency virus. Choose your state or county to find the percentage of positive cases. Parasite forecasting predicts a big year for heartworms and Lyme disease. The organization also plans to begin forecasting other diseases and parasites. -- Dr. Marty Becker, Kim Campbell Thornton and Mikkel Becker

ABOUT PET CONNECTION

Pet Connection is produced by a team of pet-care experts headed by "The Dr. Oz Show" veterinarian Dr. Marty Becker and award-winning journalist Kim Campbell Thornton. They are affiliated with Vetstreet.com and are the authors of many best-selling pet-care books. Joining them is dog trainer and behavior consultant Mikkel Becker. Dr. Becker can be found at Facebook.com/DrMartyBecker or on Twitter at DrMartyBecker. Kim Campbell Thornton is at Facebook.com/KimCampbellThornton and on Twitter at kkcthornton. Mikkel Becker is at Facebook.com/MikkelBecker and on Twitter at MikkelBecker.

When should your kitten be spayed or neutered? Earlier than you might think, experts say

By Kim Campbell Thornton

Andrews McMeel Syndication

It’s kitten season! If you are bringing home one of the little fluffballs, there’s more to think about than cuddling and catnip. Feline veterinary specialists recommend scheduling spay or neuter surgery before a kitten is 5 months old. That might seem young, especially for such a tiny animal, but cats are precocious when it comes to reproduction. Kittens as young as 4 months are capable of producing kittens of their own.

That’s just one of the reasons that the Veterinary Task Force on Feline Sterilization says the optimal age for sterilization surgery is 5 months or earlier. Supporting the recommendation are the American Animal Hospital Association, the American Association of Feline Practitioners, the Association of Shelter Veterinarians, the Cat Fanciers Association, the International Cat Association and the Winn Feline Foundation.

“The 6-month rule that so many veterinarians and so many clients have in their heads as what is perceived as the ideal time for a spay or neuter procedure is arbitrary,” says AAFP president Lauren Demos, DVM. “There is no solid basis to say that this is the reason spaying and neutering needs to be done at that point in time. There is no specific piece of data that we are aware of that says, ‘This is why cats do better at this date.’”

Kitten population control is an important facet of spay/neuter surgery. Fewer unwanted litters are always a good thing in any community. But there are other reasons veterinarians and animal welfare supporters think spaying and neutering by 5 months of age is a good idea. Performing sterilization surgery by that age has benefits for owners, cats and veterinarians alike.

I don’t know if you’ve ever heard a female cat in heat. I have, and the intensity of the screeching still sticks in my mind some 30 years later. Putting off spay surgery until she’s older can land you with a female kitten who is intent on finding male companionship and who is desirous of letting the whole neighborhood know about it. Intact male cats also vocalize, as well as mark their territory with urine and attempt to escape in search of a willing and able female. Sterilizing them before they hit puberty curbs these unwanted behaviors. It also typically costs less to spay a female who is not in full-blown heat.

Scheduling sterilization surgery at the same time as other routine kitten wellness care can help to prevent the procrastination effect that often occurs when owners must wait two months to bring kittens back in for the procedure. It’s all too easy to get caught up by other things that need to be done. Making time to get the kitten spayed or neutered is one of those things that often gets bumped down the list because it doesn’t seem urgent.

For cats, one benefit that lasts throughout life is a lower risk of mammary cancer. Because the surgery goes more quickly, kittens are typically anesthetized for a shorter period, Dr. Demos says. She adds that younger patients also bounce back more quickly from surgery.

An advantage for veterinarians is that young kittens bleed less than adult cats. They also have less body fat, making it easier to see organs.

Are there drawbacks? Some studies have found that certain dog breeds gain health benefits from spay/neuter surgery at a later age.

But cats don’t seem to have increased risk for any health problems following sterilization surgery, says Julie K. Levy, DVM, professor at Maddie’s Shelter Medicine at the University of Florida College of Veterinary Medicine.

“There’s so much vigor in the natural cat that we’re not seeing major medical outcomes for minor interventions like we might in dogs.”

Q&A

Cause of vomiting

difficult to diagnose

Q: My cat has been vomiting a lot, and my veterinarian wants to run all kinds of tests to figure out the cause. Is that really necessary? -- via email

A: Figuring out why cats are vomiting is one of the more frustrating problems veterinarians face. A whole host of problems, from hairballs to hyperthyroidism, can cause cats to vomit. Among the common causes of acute vomiting -- meaning it comes on suddenly -- are adverse reactions to food, feline infectious peritonitis and acute gastritis of unknown cause -- what we like to call “garbage gut.” Chronic vomiting, which continues over a long period, is usually related to adverse food reactions or intestinal bowel disease. But there is still a wide range of other potential causes, which is why your veterinarian may want to run an assortment of lab tests or order imaging such as radiography or ultrasound.

At last year’s North American Veterinary Conference, M. Katherine Tolbert, an internal medicine specialist at the University of Tennessee, presented some ways to help practitioners narrow the possible causes of feline vomiting. These include looking at the cat’s age, breed and sex. For instance, a middle-aged Siamese might have gastrointestinal adenocarcinoma, while a young Abyssinian is more likely to have feline infectious peritonitis. A middle-aged or senior domestic shorthair should get a thyroid panel to rule out hyperthyroidism. A shorthaired cat who frequently vomits hairballs may have chronic gastrointestinal disease.

Any details owners can provide are important, no matter how minor they might seem. Always let the veterinarian know how often the cat vomits, whether he’s eaten anything unusual or new, or any change in his routine or environment. Depending on the cat’s medical history and the severity of the signs, it may be possible to start with a fecal exam or diet trial before moving on to more specialized diagnostics. -- Dr. Marty Becker

Do you have a pet question? Send it to askpetconnection@gmail.com or visit Facebook.com/DrMartyBecker.

THE BUZZ

Cats keep theme

park pest-free

-- Planning a visit to Disneyland this summer? Keep an eye out for some feline characters that you might not have known about. No, not Tigger or the Cheshire Cat. We’re talking Ned, Lucian, Buford, Bernice, Giovanni, Hector, Peter, Jane and Francisco. They are the Disneyland Cats, and their motto is, “When the mice are away, the cats can play.” That’s right, their job is to help keep the park free of mice. Employee benefits include food stations, spay/neuter surgery, vaccinations and other medical treatment as needed. Of course, there’s one mouse who doesn’t need to fear the DC team: M-I-C-K-E-Y.

-- A brewing company offers an unusual and welcome benefit to dog-loving employees: “paw-ternity” leave. That’s right; if you’ve acquired a new dog, you can take a week off to help get your pup acclimated to his new people and surroundings. BrewDog, which recently opened DogTap in Canal Winchester, Ohio, says it is the first company in the United States to offer the benefit, which is available to the multinational brewery and pub chain’s employees around the world.

-- What are the top medical conditions that affect pets? Pet health insurer Nationwide searches its database of 600,000 pets annually to determine the main reasons pets go to the vet. For dogs last year, allergic dermatitis was the No. 1 health concern, with more than 102,000 claims at an average cost of $233, followed by otitis externa (ear infections), benign skin growths, pyoderma (itchy skin), osteoarthritis, gum disease and tooth infections, gastrointestinal problems, cystitis or urinary tract disease and anal gland issues. Cats suffered from periodontal problems, cystitis or urinary tract disease, kidney disease, gastrointestinal problems, hyperthyroidism, diabetes mellitus, inflammatory bowel disease, allergic dermatitis and valvular heart disease. The most expensive feline condition to treat was diabetes, at an average cost of $905. -- Dr. Marty Becker, Kim Campbell Thornton and Mikkel Becker

ABOUT PET CONNECTION

Pet Connection is produced by a team of pet-care experts headed by "The Dr. Oz Show" veterinarian Dr. Marty Becker and award-winning journalist Kim Campbell Thornton. They are affiliated with Vetstreet.com and are the authors of many best-selling pet-care books. Joining them is dog trainer and behavior consultant Mikkel Becker. Dr. Becker can be found at Facebook.com/DrMartyBecker or on Twitter at DrMartyBecker. Kim Campbell Thornton is at Facebook.com/KimCampbellThornton and on Twitter at kkcthornton. Mikkel Becker is at Facebook.com/MikkelBecker and on Twitter at MikkelBecker.

The latest ways to help dogs and cats cope with common allergies

Andrews McMeel Syndication

Is your dog or cat itching and scratching uncontrollably? It’s frustrating and sometimes even disturbing to see them so uncomfortable as they lick and chew at their feet and flanks, or frantically rub their faces on the carpet.

Itchy skin is a common problem in pets. Pollen, mold, grass, trees, weeds, dust, flea bites and some food ingredients can all cause itchiness and other allergic reactions.

Determining what’s behind the itchiness is a process of elimination. Your veterinarian may look for flea dirt on your pet’s body and recommend a preventive product if your dog or cat isn’t already on one; perform skin scrapings to check for infections caused by bacteria or yeast, which commonly accompany allergies; or suggest an elimination diet to rule out food allergies.

Pets who get itchy only at certain times of the year or who aren’t helped by flea-control products or a change in diet are likely suffering from an inhalant allergy caused by pollen, mold or dust. Food allergies, which are more common in cats than in dogs, usually involve sensitivity to common animal or plant proteins, such as beef, chicken or soy.

Can allergies be eliminated? There’s no magic bullet to resolve them, and many pets need a combination of therapies for best results. A cure is unlikely, but better treatments are available -- or in the pipeline -- to help quell the itching, runny eyes, ear infections and snoring that often accompany allergies in pets.

Drugs called kinase inhibitors work by changing cellular function to fight itchiness. An example is a drug called Apoquel (oclacitinib).

“Results in head-to-head studies against either prednisolone or cyclosporine show the drug to be equally effective in control of itch and inflammation and to have a very rapid onset of action, with relief sometimes apparent within hours of oral administration,” said board-certified veterinary dermatologist Dr. Douglas J. DeBoer of the University of Wisconsin School of Veterinary Medicine in the proceedings of the 2016 North American Veterinary Community Conference in Orlando, Florida.

Other biologics with promise are called monoclonal antibodies. They are a type of immunotherapy that can be directed against key molecules that cause itchiness. A monthly injectable treatment is available for dogs.

Some dogs respond to old-school immunotherapy: allergy shots. Testing determines the substances to which the dog is allergic -- cats, for instance, or Bermuda grass. Then a veterinary dermatologist creates an allergy shot to hyposensitize the dog to specific allergens. Up to 75 percent of dogs get relief from allergy shots, although some may need additional therapies at certain times of year, depending on the type of allergy.

A more conservative treatment that is a good adjunct to medications is a high level of supplementation with essential fatty acids, or EFAs. They can have anti-inflammatory effects and may help to improve the skin’s barrier function -- its ability to control colonization by bacteria that cause itchy skin infections. It usually takes a month or two before effects are noticeable. Topical treatments such as shampoos and moisturizers can also help to enhance barrier function.

For pets who may have food allergies, an elimination trial -- feeding a food that contains ingredients a pet has never eaten before -- can help to identify the dietary culprit.

It’s a painstaking process. Simply switching from one brand or protein to another isn’t enough, because most commercial pet foods contain trace amounts of allergens that may not be listed on the label. That’s why trial diets usually comprise odd combinations such as kangaroo and oats or fish and potatoes. If the pet improves after eight to 12 weeks of eating only the hypoallergenic diet (no treats or table foods), ingredients are added back into meals one by one until it’s clear which one is causing the problem.

Q&A

Vitamin D

for dogs?

Q: If vitamin D supplementation is beneficial for humans, can it benefit dogs, too? -- via Facebook

A: That’s a great question! Researchers at Cornell University College of Veterinary Medicine published a study in the January/February 2014 issue of the Journal of Veterinary Internal Medicine suggesting that vitamin D deficiency could be a risk factor in congestive heart failure (CHF) in dogs.

They analyzed 31 dogs with CHF related to chronic valvular disease or to dilated cardiomyopathy, with 51 dogs unaffected by heart disease serving as controls. All the dogs were patients at Cornell University Hospital for Animals, which meant that blood samples could be taken simultaneously for evaluation of vitamin D levels.

The dogs with CHF had significantly lower levels of vitamin D in the bloodstream than the control dogs. A planned second phase of the study would supplement dogs being treated for CHF with vitamin D in addition to their regular medication.

Does this mean that owners whose dogs have heart disease should be giving their pets vitamin D? No. Excess doses of vitamin D can cause a condition called hypercalcemia. Depending on the severity of it, signs can range from lethargy and decreased appetite to kidney failure and even death. Without more information, supplementation isn’t recommended.

In this study, the dogs’ diet was not controlled, and the food they ate was not analyzed for vitamin D levels, so the amount of vitamin D they received through their diet was an estimate. Also, vitamin D can be stored in body fat. That could reduce the levels of vitamin D found in circulating blood. Joseph Wakshlag, a Cornell veterinary nutritionist, suggests that the lower levels of vitamin D found in dogs with CHF may mean that some element of the disease causes a lower concentration of vitamin D in circulating blood. -- Dr. Marty Becker

Do you have a pet question? Send it to askpetconnection@gmail.com or visit Facebook.com/DrMartyBecker.

THE BUZZ

Dog bites rise

for postal workers

-- It’s no joke when dogs bite postal employees. The number of postal workers attacked by dogs rose by more than 200 last year, for a total of 6,755. Los Angeles ranks highest among the 40 cities where postal workers are most likely to be bitten. The other cities in the top 10 are Houston, Cleveland, San Diego, Detroit, Denver, Chicago, Indianapolis, Minneapolis and Louisville, Kentucky. To prevent your dog from biting a delivery person, put him in a separate room and close the door before accepting a delivery. Teach children not to take mail directly from letter carriers if the dog is nearby.

-- How do a cat’s whiskers work? Technically termed "vibrissae," the specialized, highly sensitive hairs located on either side of the muzzle, above the eyes and elsewhere on the body, have multiple uses. Cats use them to detect small changes in air currents, alerting them to the approach of obstacles or other animals that might pose a danger. Whiskers also help cats to measure the width of an opening, determining if they will fit through it. Finally, whiskers are a telltale signal of a cat’s mood. When forward, the cat is friendly or curious. But back? Watch out!

-- Their soft, thick fur, large ears and long lifespan -- 10 to 15 years or more -- can make chinchillas attractive as pets, but they have some special needs. It’s important to handle them calmly to prevent them from losing large patches of fur at once. The crepuscular animals are active at dawn and dusk, so don’t count on them being entertaining during the day. They are sensitive to heat and need to live in an air-conditioned environment. A good diet for chinchillas includes commercial pelleted foods, plus high-quality hay and small amounts of treats, such as apples, unsalted sunflower seeds and dry oatmeal. -- Dr. Marty Becker, Kim Campbell Thornton and Mikkel Becker

ABOUT PET CONNECTION

Pet Connection is produced by a team of pet-care experts headed by "The Dr. Oz Show" veterinarian Dr. Marty Becker and award-winning journalist Kim Campbell Thornton. They are affiliated with Vetstreet.com and are the authors of many best-selling pet-care books. Joining them is dog trainer and behavior consultant Mikkel Becker. Dr. Becker can be found at Facebook.com/DrMartyBecker or on Twitter at DrMartyBecker. Kim Campbell Thornton is at Facebook.com/KimCampbellThornton and on Twitter at kkcthornton. Mikkel Becker is at Facebook.com/MikkelBecker and on Twitter at MikkelBecker.