Sheila Pell is a journalist and contributor to The Bark.
Wellness: Healthy Living
Toxic chemicals also found in dog food
August 10 2016
A long-term study conducted in Britain has found that male dogs are losing fertility, and that exposure to environmental chemicals (ECs) that have leached into the environment may be to blame.
The dogs—Labradors, Border Collies, German Shepherds and Golden Retrievers bred to aid the disabled—made an ideal group to explore the larger question of a decline in human semen quality that has been occurring since long before this study.
This twenty-six year long study, 1998-2014, was conducted by Richard Lea and colleagues at Nottingham University’s school of veterinary medicine. They collected annual samples of semen from dozens of dogs, all from the same breeding program, all healthy and well cared for. Each year, the same problem recurred; a 2.4 percent dip in sperm motility, that is the ability to swim in a straight line. In addition to monitoring semen quality, they analyzed health records, finding an increase in cryptorchidism, a condition in which the testicles fail to extend normally to the scrotum. Over the same years, fewer male pups were born than females, also there was an increase in fetal and prenatal female mortality.
And, lurking in the samples of semen and testicles of dogs obtained from neutering, it found ECs—chemicals that tamper with hormones. The chemicals include polychlorinated bisphenol (PCB), a compound banned in 1977, and diethylhexyl phthalate (DEHP). PCBs don’t readily break down while phthalates are common in a wide number of products, from cosmetics to detergent. Both chemicals are associated with fertility issues and birth defects.
In human babies, exposure to chemicals has been linked to faulty development of semen quality and cryptorchidism. According to the study, such reproductive problems often cluster in geographical areas, and so are suspected of having a common cause; exposure to hormone-disrupting chemicals is “thought to be the initiator.” To explore the same possibility in dogs, chemicals were measured in canine testes and semen taken from the same geographical area where the study took place.
Both chemicals “perturbed sperm viability, motility and DNA integrity in vitro.” The researchers concluded that the direct effects of chemicals on sperm “may contribute to the decline in canine semen quality” that parallels that in humans.
“Why the dog?” said Dr. Lea. “Apart from the fact that it is a great population of animals to work with, dogs live in our homes, they sometimes eat the same food, they are exposed to the same environmental contaminants that we are, so the underlying hypothesis is that the dog is really a type of sentinel for human exposure.”
The same ECs were found in a range of commercially available dog foods. DEHP and PCB153, “were detected in adult dog testes and commercial dog foods at concentrations reported to perturb reproductive function in other species.”
While the brands were not named, they are reported to be both wet and dry forms sold worldwide. The scientists don’t know how the chemicals made it into the food, but since they are not deliberate additives, they may have leached from the packaging or processing sources.
These overall findings are troubling, but they also noted that: “Amongst the dry dog food samples, one sample designed for puppies (1 to 24 months of age) had higher concentrations … relative to the other samples tested.”
Plus, while the researchers cannot say the dog food is a direct source of the ECs, the New York Times reports that "Dr. Lea said it was probably a major one."
What is known is that the chemicals wound up in dog’s testicles, where they messed with sperm motility and viability. “This may be a way by which environmental chemicals directly affect male fertility.”
While the dogs in the study were still able to reproduce, it’s hardly reassuring that, once more, the dogs who share our homes also share our diseases, unwittingly, acting as the “canary in the mine” for us.
Wellness: Food & Nutrition
A vet speaks out on genetically modified pet food.
April 21 2016
Most dogs now dine on some type of genetically modified (GM) food, often in the form of corn and soy in their kibble. As these ingredients increasingly enter the food supply, we have one more reason to wonder if our shopping choices might be harming our pets.
More animal feeding studies are needed, experts say, and a recent long-term, peer-reviewed report points out why. It found that a diet of GM corn and soy led to higher rates of severe stomach inflammation in pigs, which are physiologically similar to dogs.
Robert Silver, DVM, a Boulder, Colo., holistic vet, tackled the issue earlier this year when he presented his paper, “Genetically Modified Food and Its Impact on Pet Health” at the American Holistic Veterinary Medical Association conference in Kansas City, Mo. Why did he choose this controversial topic, one that few vets even acknowledge?
Silver—a pioneer in the field of holistic veterinary medical practice—says he was inspired by a seminar he attended in Boulder on GM foods and human health. The speakers included Don Huber, a Purdue University professor, and activist Jeffrey Smith, who discussed problems, including reproductive difficulties, that have occurred in livestock fed GM crops.
“I found this seminar mind-opening,” says Silver, the lone vet in attendance. “I had always believed the PR about GM foods—that they are going to feed the world and are a good outcome of our genetic technology.”
The Food and Drug Administration, which regulates the safety of GM crops consumed by humans and animals, considers most GM plants “substantially equivalent” to traditional plants and “generally recognized as safe.” Their regulation involves a voluntary consultation process with the developer before products are brought to market.
Smith, founder of the Institute for Responsible Technology, disagrees. On its website (responsibletechnology.org), he warns that “nearly all GM crops are described as ‘pesticide plants.’ They either tolerate doses of weed killer, such as Roundup, or produce an insecticide called Bt-toxin. In both cases, the added toxin—weed killer or bug killer—is found inside the corn or soybeans we consume.”
Silver says that while “allergies, GI problems, increased risk of cancer, neurodegenerative conditions” and other ills could all be, in part, related to GM foods, “there is no objective evidence of this yet” in dogs. “However, all vets will agree that there has been an uptick in [these diseases] in the past 10 to 20 years.” The advent of GM foods in the 1990s “fits into this timing of disease increases,” he says.
His presentation referred to studies that raise doubt about the safety of biotech crops, such as one reported in 1996 in the New England Journal of Medicine, which found that genes inserted into crops can carry with them allergenic properties.
Silver says that genetic modification introduces foreign proteins that may encourage allergies, and the widely planted Bt corn, which makes its own insecticide, “could possibly cause leaky gut, the gateway to chronic disease.” Corn is a major component of most commercial pet foods. “The big problem with commercial foods is that they are manufactured at high temperatures and pressures,” which alters them and makes them “potentially more allergenic.” And commercial foods contain industrial ingredients that are “more likely to contain GM and herbicide contaminants.”
A study published last year found that GM crops engineered to withstand the toxic herbicide Roundup must now be doused with even more herbicide, since weeds have also developed resistance to it. Residues of these chemicals on crops can find their way into pet food.
A 2013 study published in the science journal Entropy reports that the heavy use of Roundup could be linked to Parkinson’s, autism, infertility and cancers. It goes on to report that residues of Roundup in food can interact with, and enhance, the damaging effects of other environmental toxins. “Negative impact on the body is insidious and manifests slowly over time as inflammation damages cellular systems throughout the body,” the study’s researchers say.
According to Silver, heightened sensitivity to dietary ingredients “is probably what we are seeing with GM foods. It is of concern that this may be driving the increase in GI problems in pets.” Although gluten probably does account for some problems with grain consumption, “I think that grain-free diets, if they are also soy free and contain protein from animals not fed GM crops, can help many dogs, due to being GM free—and not due to some allergy or gluten issue.”
To a holistic doctor, food is medicine, and Silver strongly recommends home meal preparation from individually sourced ingredients to avoid feeding GM ingredients, especially to pets who have other health problems. “I am truly a holistic practitioner in that I believe an ounce of prevention is worth a pound of cure.”
Benbrook, C.M. 2012. Impacts of genetically engineered crops on pesticide use in the U.S.—the first 16 years. Environmental Sciences Europe 24: 24.
Ordlee, J., et al. 1996. Identification of a Brazil-nut allergen in transgenic soybeans. The New England Journal of Medicine 334: 688–692.
Samsel, A., and S. Seneff. 2013. Glyphosate’s suppression of cytochrome P450 enzymes and amino acid biosynthesis by the gut microbiome: Pathways to modern diseases. Entropy 15 (4): 1416–1463.
Wellness: Health Care
What should we be looking for?
March 18 2016
When it comes to giving a dog a pill, a tasty disguise is often in order—trickery helps deliver the goods. But what if the dog isn’t the only one being fooled?
Sales of pet supplements are soaring, prescription drugs (“no prescription required”) are just a click away, and pharmacies are creating compounds tailored to a dog’s individual needs. Yet, tests keep proving that remedies aren’t always what their labels claim.
Veterinary drugs are federally regulated, but supplements fall into a regulatory abyss. In both cases, critics say, oversight is lacking. While Internet shoppers risk buying fake, unapproved and contaminated products, tainted pills can also be found on store shelves and in pharmacies.
Access to affordable medications is another issue. Can’t find a generic version of that expensive drug? It may be hidden in plain sight, thanks to covert efforts to block it.
Supplements, More or Less
This boom follows a recession-era slump, according to market-research firm Packaged Facts. Riding in on the wave is a stream of “natural” and organic supplements targeting obesity, aging and joint health. But sales of these products still lag behind sales of nutraceutical treats like functional biscuits (which also offer taste appeal), so companies are shaping their ingredients into new liquids, powders, gels and pastes.
All of which suggests that more dogs will be given questionable products.
“It is definitely a buyer-beware situation for pet owners,” says Tod Cooperman, president of ConsumerLab.com, an independent testing company that keeps tabs on health supplements. When the company started in 1999, defective vitamins were making news, but there was little testing. “I realized that consumers needed more information,” says Cooperman, who began the venture with former FDA chemist Dr. William Obermeyer.
In 2003, the lab analyzed its first pet-specific product, the popular joint-care staples glucosamine and chondroitin. “We found two supplements which had no chondroitin despite a guaranteed analysis on the labels showing significant amounts.” While many people think such work is the job of the FDA—or, for pets, the Center for Veterinary Medicine (CVM)—it’s up to manufacturers to test for safety and follow good manufacturing practices. Federal rules don’t recognize pet supplements at all unless companies put them in food or claim they treat illness.
“Government oversight of the manufacture of supplements for people is minimal; oversight of supplements for pets hardly exists,” Cooperman says. “In general, a lower percentage of pet supplements pass our reviews of quality.”
The problem is compounded (no pun intended) by the fact that China, origin of many tainted pet products, is the world’s leading supplier of nutritional raw materials. But issues with ingredients aren’t confined to any one country, and mistakes can occur at various points in the manufacturing process. According to Cooperman, “A pet owner is trusting the supplement maker to formulate a product with the right amount and type of ingredients, and to make it properly without contamination.”
Recently, ConsumerLab tested five kinds of pet supplements: probiotics, joint health products, fish oils, plant-based oils (like flaxseed) and multivitamins.
Tests of three probiotics for dogs and cats found that two had high amounts of the beneficial organisms, more than one billion per daily serving, as claimed. However, Cooperman says, the third contained such a small amount that its efficacy is highly questionable. As with previous testing, products for veterinary joint health fared poorly. None of them had exactly what they claimed. Three contained only 16 to 76 percent of the listed glucosamine. One exceeded its label, packing 36 percent more MSM, an anti-inflammatory compound. Could the excess be harmful?
“It’s okay for companies to add a bit more ingredient than listed, but not that much,” Cooperman notes, adding that it suggests “a possible manufacturing issue.” Of greater concern was another product that provided only 16 percent of its listed chondroitin, a particularly expensive ingredient. “We’ve been finding pet supplements short on it for many years.”
He notes that two joint-health products voluntarily tested in the website’s rigorous certification program passed, receiving the “Seal of Approved Quality.” The lab buys the samples from brick-and-mortar or online stores, as a consumer would. “Manufacturers can’t send us products. This way, the quality we find is likely to represent what [consumers] are getting off the shelf,” he says. The seal, good for one year, applies to a particular product and can only be used in conjunction with that product.
Of the fish oils, all three did well, Cooperman reported. They contained plentiful omega-3 fatty acids, EPA and DHA. Both plant oil supplements for skin and coat also passed. But potency aside, what about contaminants like mercury, which could easily be far higher in products for animals?
“We test all fish oils for mercury and other heavy metals, [including] lead, cadmium and arsenic,” he says. “The good news is that we have not found mercury in fish oil.” That’s because mercury binds to fish muscle, not fat, and the oils are purified. The bad news: “We have found higher levels of PCBs in some fish oil for pets than in those for people. PCBs (polychlorinated biphenyl) are carcinogens and can have other harmful effects.”
In the pet multivitamin category, all three products flunked across the board. One had just 30 percent of the vitamin C listed on the package. Another contained only 52 percent of the vitamin A it claimed. And one, the worst example of mislabeling, had a mere 16 percent of the vitamin C and only 7.5 percent of the vitamin A it touted.
As ConsumerLab keeps proving, these aren’t isolated incidents. “We believe that the FDA is aware of our findings, but if serious injury is not being reported, they are unlikely to take action. It’s up to consumers to educate themselves and purchase wisely. I recommend that people see what’s passed our tests,” Cooperman advises. (For the cost of a subscription, consumers can access test results on the company’s website.)
Still, online shopping is a gamble even with brand names; the FDA warns that unscrupulous companies are selling fake or otherwise mislabeled pet supplements. Cooperman says that Internet sites seem more focused on customer service than product quality, and, “Unfortunately, you can’t just rely on a brand to always produce good products. There are plenty of products that have failed miserably in our tests, yet continue to be sold.”
Compounding for Better and Worse
As it turns out, a lot of people. Sometimes, a dog needs a medication that’s not readily available. Once a dilemma, with a vet’s prescription, the answer is now often found at a compounding pharmacy. Think custom drug. Does your pup manage to eat the treat and spit out the pill every time? Turn the pill into a tasty liquid.
It can also allow more exact dosing. Say your dog needs a 45 mg dose of a drug that only comes in 10 mg or 40 mg capsules. No need to round it down to 40 mg, the usual solution; compounding can yield the ideal strength.
It might seem that such precise formulas would be safer and more effective. But that’s not always so. For one thing, while the drugs they’re made from are FDA-approved, compounding (by mixing, diluting or other changes) yields a whole new product. The resulting drug isn’t safety tested, FDA-approved or even sure to work. It’s pharmaceutical roulette — as injuries, deaths and recalls have shown.
How can it go wrong? The list is long: with sanitary problems, like the deadly 2012 human outbreak of fungal meningitis linked to a high-volume compounding pharmacy; with too much of one drug along with unapproved drugs used in a combination, which killed several horses in 2014; with drugs prescribed for owners that can be fatal to pets, seen with compounded pain creams last year (in cats, but dog owners were also alerted); and with solutions that deteriorate before the expiration date, as was found—along with a “five-fold compounding error”—in a study of compounded medications for dogs.
In a recent study, University of California, Davis, veterinary researchers report another disturbing glitch. CCNU (lomustine), a drug their hospital relies on, is a staple in the treatment of cancers such as mast cell tumors and lymphoma. When drug companies run out, the university’s vets turn to compounding pharmacies. That’s what happened in 2013; then, they noticed something odd.
Animals treated with the compounded CCNU weren’t showing the usual drop in the number of white blood cells the drug is intended to achieve, while every animal given the FDA-approved version did have this result. Tests found that the strength of the compounded capsules varied widely. Some had only half what their labels claimed.
With chemotherapy, there’s a very a narrow margin between an optimally effective and a toxic dose, the researchers say. That’s why compounded cancer drugs can improve treatment. The FDA regulated CCNU, for example, only comes in two strengths, a limitation overcome by the compounded version.
Also, compounded drugs are sometimes far cheaper. The UC Davis researchers say that a compounded version of an FDA-approved drug can sometimes be purchased for one-third of the cost of a brand name.
But quality-control issues can also arise when cost-cutting involves mass production of compounded drugs. The Massachusetts pharmacy behind the meningitis outbreak charged about two dollars less per vial for their drug, but they were illegally making drugs for broad use rather than filling individual prescriptions. This practice was soon exposed at other pharmacies as well.
FDA regulations generally allow compounding for animals using approved human or animal drugs, but not bulk active pharmaceutical ingredients. Oversight has mostly fallen to state boards of pharmacy. However, according to the International Academy of Compounding Pharmacists, only 17 states mandate following USP drug standards, strict guidelines set by the nonprofit U.S. Pharmacopeial Convention.
The UC Davis researchers, who are now investigating other chemotherapy drugs, agree that more oversight of compounding is needed. They advise veterinarians and owners to weigh the pros and cons of choosing a compounded formula over standard drugs, especially when treating cancer. Know the risks in getting a drug that’s weaker or stronger than expected. In chemotherapy, missing the target in either direction can be deadly.
There were few of these affordable options in 2006 when Maine’s Portland-based Putney, Inc., founded by Jean Hoffman, took up the challenge. While the lack of competition was good for drug companies, it didn’t bode well for animals, as Putney spokesperson Susan Hanley explains.
“With few veterinary generic options, many pet owners couldn’t afford their veterinarian’s recommendations, especially for drugs needed every day.” So vets would sometimes prescribe human generic drugs instead. Unfortunately, most pet drugs have no human version, she says, and for those that do, dosing can be off due to differing strengths or formats.
Putney was the first to develop generic prescription drugs specifically for veterinary use, Hanley says. “We know from a nationwide survey that 87 percent of pet owners would choose a veterinary generic of their pet’s medicine if their veterinarian offered one.”
Change has come slowly. A Putney analysis through 2014 found that 91 percent of all approved drugs for dogs and cats still have no generic equivalent. The company pushes on and to date, has landed a total of 10 CVM approvals for veterinary generic drugs. The approval signals that a generic pet drug is bioequivalent to the branded version, Hanley says.
Each drug they develop is made in a plant that also makes FDA-approved human drugs. To oversee products, their experts visit manufacturers of both finished drugs and active ingredients. While they don’t sell drugs to Internet pharmacy sites, Hanley notes, “they are often available there anyway.” Currently, the company has several drugs in development and review stages. She can’t reveal them, but says they have “some exciting new generics expected next year.”
Meanwhile, brand-name drug-makers haven’t been idle as other companies make more affordable versions of their products. Some are fighting back with blocking agreements, which Hanley calls “unusual contracts in the pet drug market, signed by a branded veterinary drug company and all the national distributors serving veterinary clinics.” The brand company lets distributors profit from a list of drugs veterinarians often prescribe, with one caveat: they must promise not to carry any generic version of the brand drug.
According to Hanley, the first such agreement was put in place by Zoetis (under the predecessor name Pfizer Animal Health) in 2005, right before initial approval of a generic for Rimadyl, the company’s popular arthritis treatment for dogs. “We also have verbal evidence that blocking agreements have been in use by various brand companies since 2005,” she says. “The contracts block vets, and their pet-owner clients, from gaining the cost savings of FDA-approved generics.”
While the cost of generic medications has shot up in recent years, generics are still typically cheaper than the brand-name version. Since statistically, companion animals are living longer, obstacles to obtaining cheaper drugs have a greater potential impact. Price can be a barrier when it comes to treating a dog or cat’s chronic condition, and if the animal’s health is fragile, their lives may depend on consistent access to a medication.
The pill market is full of pitfalls. Those who turn to supplements to ease ailments, or in the hope of avoiding the need for drugs in the first place, also gamble. Here’s the proverbial bottom line: reduce the risks by remaining vigilant and taking the advice of experts.
September 28 2015
It may take more skill than a belly rub, but should massage only be allowed with veterinary supervision? California is the latest state to propose regulating the field of animal rehabilitation, and it could put many kinds of practitioners out of work.
With preventive health care booming, the state’s veterinary board wants to rein in non-veterinary businesses that cater to wellness, saying they “pose a grave danger” to pets and can increase costs for owners. The rule would mean only veterinarians, or physical therapists and registered vet techs, if supervised, could perform animal rehabilitation..
Opponents of the rule say the board has defined the field so broadly, it nets the use of electricity or biofeedback right along with exercise and simple massage used to soothe aching seniors, relax dogs that play sports, and socialize shelter pups.
“It is about defining everything as rehab, even swim facilities and pet certified fitness training,” says Linda Lyman, who attended a recent public hearing in Sacramento to air her concerns. Lyman says she has a PhD in physical education, has taken a canine medical massage course, and for seven years has operated Pawssage, a canine massage practice.
“I go to agility trials every weekend and massage dogs before, between, and after they run. My goal is always to make sure my client’s dogs can hike, walk, and do things with their owners while and when they quit agility.”
As the board’s proposal would have it, Lyman is practicing veterinary medicine without a license. Aside from the hands-on, she makes suggestions that could get her in trouble under the new law. At her recommendation, three clients bought pools for their dogs, for example.
In many states, a background like Lyman’s isn’t needed. Anyone can provide animal massage, including evaluation, treatment, instruction, and consultation. That currently includes California, where only “musculoskeletal manipulation” by the layperson is forbid. Other states call for direct veterinary supervision of the work, or allow it with a vet’s referral. Some require certification, like the state of Washington, where a 300-hour training course in general animal massage, first aid and more is needed.
Whether body workers massage humans, which calls for state licensing but not doctor supervision, or pets, “the good ones survive and thrive and the rest fall by the wayside, certification or not,” Lyman says.
In a few cases, lawsuits have accused vet boards that restrict massage of stifling competition. In Maryland, providers of horse massage successfully challenged the state vet board, and a recent Arizona lawsuit argues that massage is not a veterinary service.
Another meeting will be held on October 20-21, when the board will discuss comments received so far, and possibly vote on the final rule.
Lyman sees more at stake than massage, or any one service, she says. “This is about a pet’s access to all practitioners who can help it maintain a healthy lifestyle.”
News: Guest Posts
September 19 2015
As embers fell and flames grew, the question of “what to take” often came down to a four-legged bundle. But the Valley Fire in California’s rural Lake County left many with just minutes to escape as it sped through parched brush in record time.
“The community had to leave so fast that hundreds of animals were left behind,” says Bill Davidson, director of Lake County Animal Care and Control.
Countless dogs that managed to stay with their people soon joined cats, goats, horses and more in evacuation centers crammed with cots and crates. One local shelter had to face its own tough choices; whether to euthanize existing animals to make way for the incoming. (Luckily, these two groups stepped in).
In South Lake County, where the 73,700-acre blaze began, among the worst in California’s history, the roads out are windy and narrow, through rock-strewn mountains and forests, with yawning drops at every bend. In 2011, a group of horse owners along with Davidson formed the Lake Evacuation and Animal Protection team (LEAP) to help prepare for the inevitable, catastrophic fire.
The volunteer group has trained to enter the fire area and either impound or shelter in place. The vast majority of city and county animal control agencies lack the training, equipment, or support from local fire agencies to do the work, Davidson says.
In recent days, some people ventured back into smoldering fire zones, escorted by sheriff’s deputies and CHP officers for a 15-minute check on the animals they’d left behind. Some would find their homes; others would not.
“Everyone is calling to have us check on their animals,” says Davidson. “The list is endless.” With the enormity of the crisis, he called in the ASPCA. Everyone wants to help, he says, but LEAP only uses those with fire training and personal protection equipment. The fire zone, where animals still wander, is filled with dangers. “Many things are actively burning, trees are falling, power lines are down, and fire crews are running around to trouble spots.” On Sunday, the ASPCA arrived with a 30-foot trailer. The four field rescuers and three shelter helpers are expected to stay through Sunday.
“We brief each morning and then they are gone for most of the day, not returning to well after midnight so far,” Davidson says.
The field rescue is uplifting at times, heartbreaking at others.
“As long as the property was spared, most dogs have done well,” he says. “Our goal has been to shelter in place as many as possible, providing food and water for the absent owner, then moving on to the next address.” If they survived the initial blast, most are far more comfortable and easily managed staying at home.
But over 1,000 structures were likely destroyed, “pretty much a total loss, including anything left inside,” he says. “The injured animals have been trickling in, all being sent for medical attention.”
How many dogs are missing? Davidson is sure there are hundreds that escaped yards or were set loose by their owners. “Social media has been full of pictures of animals set free by their owners before leaving. We have impounded about a dozen dogs just wandering around as we check on addresses.”
Lake County’s animal shelter now brims with almost 200 animals whose lives were upturned by fire…again.
In August, the county was struck by another roaring inferno; the Rocky fire, nearly as large but in a less populated area. Less than two weeks later the Jerusalem fire ignited. Help arrived from Chico-based North Valley Animal Disaster Group, but the run of disasters has left shelters reeling. And with some 600 homes lost, many people and pets are homeless.
“We survived the Rocky and Jerusalem fires, but it pretty much depleted our resources, both physically and mentally,” Davidson says.
“Then this came.”
News: Guest Posts
September 8 2015
With their extremes of limb and coat, purebred dogs may seem more prone to health problems. And don’t breeders even compound defects, as they tinker with uniformity? Yet the dog of many varieties, a potluck of traits, outlasts them all.
Not quite, say U.C. Davis researchers in a recent study lead by Anita Oberbauer in Canine Genetics and Epidemiology. Their analysis of health records of 88,635 dogs, both purebred and mixed breeds, tilts assumptions. So does another recent study, in which they found both populations shared similar risk for 13 inherited disorders. One condition was even more prevalent in mixed-breeds.
Purebreds, and their health records, have made it easier to explore the genetics of diseases that get passed down, the researchers say. But as we hear about the studies, the belief that purebreds are less healthy grows. In fact, many breeds have proven more prone to some diseases, like Great Danes and hip dysplasia.
In this study, they sliced the data thinner. Could particular AKC breed groups, not just individual breeds, be the source? Do the diseases arise from dogs with genomic similarities like working and herding groups? The huge pack of canines, seen over 15 years at U.C. Davis veterinary teaching hospital, showed that ten inherited conditions are more common in purebred dogs. But surprise, not all purebred dogs.
A subset of pedigreed pups tied with mixed breeds for the disorders.
The conditions include aortic stenosis (narrowing above the aortic heart valve or of the valve); skin allergies; bloat; early onset cataracts (clouding of the lens inside the eye); dilated cardiomyopathy (enlargement of the heart chambers); elbow dysplasia (abnormal tissue growth that harms the joint); epilepsy (brain seizures); hypothyroidism (underproduction of thyroid hormones); intervertebral disk disease (affects the disks of the spine, causing neurological problems); and hepatic portosystemic shunt (abnormal blood circulation around the liver, rather than into it).
With a spotlight on the ten maladies, the researchers set out to learn which canines are more at risk. Purebreds were subdivided into categories, then compared to the mixed breeds.
For three conditions common across the purebreds—skin allergy, hypothyroidism, and intervertebral disk disease—many groups had higher prevalence than the mixes. But for seven others, most purebred groups were statistically neck and neck with mixed-breeds. (Aortic stenosis, gastric dilation volvulus, early onset cataracts, dilated cardiomyopathy, elbow dysplasia, epilepsy, and portosystemic shunt).
Terrier groups even bested the mixes for one problem, having less intervertebral disk disease.
Among the purebred groups, health differences were clear. Compared to mixed breeds, terriers and toys were more likely to have two disorders. Herding and hound groups were more burdened with four conditions. The non-sporting group, where pooches ranging from Poodles to Dalmatians fit in, were more likely to have five disorders. Working breeds, animals expected to have grit and vigor; six. Worst in health: the sporting group bred for outdoor stamina. They were more at risk for seven inherited disorders.
In fact, in three categories of dogs bred for endurance—herding, sporting, and working AKC groups—aortic stenosis, the heart condition present at birth, was higher. With narrower focus, other findings emerged. The researchers say the data “suggests that most breeds in the herding group are not at higher risk”—except the German Shepherd, which other studies have also found susceptible.
And while Retrievers were more affected by aortic stenosis, another sporting breed, the Spaniel, wasn’t. For a different malady, Spaniels were the unluckiest. Epilepsy was more prevalent in herding, hound, and sporting groups, particularly the Spaniel breeds.
Early onset cataracts beset both non-sporting and sporting breeds more often.
How did all of these health glitches arise? The study mentions other research that found some diseases, like elbow dysplasia, are more frequent in dogs of related ancestral origin. The so-called “liability genes” may hail from founding ancestors of related breeds, or be the result of human error in the quest for desired traits. This study, the authors say, “may shed light on the possible origin of certain inherited disorders in domestic dog evolution.”
For the ten diseases, the analysis found some purebreds genetically healthier than others. Flipped around, mixed breeds were no healthier than certain purebreds. But both populations may benefit from the work. According to the researchers, defining the lineage associations for such disorders may bring about new therapies.
Better, it could allow breeders to weed out the responsible genes to begin with. Especially at the local level. “Whether breeding reforms will mitigate inherited disorders in mixed-breeds will depend upon the locale,” the scientists say. That is, some regions have a greater potluck of breeds within their mixed-breeds.
Still, since most mixes have purebred ancestors, they say, improvement of the genetic health of purebreds “may trickle down to mixed-breed dogs.”
News: Guest Posts
Be sure where it comes from
July 29 2015
There’s a new concern about fish, and once again, labels won’t clear it up. The hidden ingredient in some pet food is slave labor used to harvest small forage fish like mackerel. A New York Times expose of brutal conditions on Thai fishing ships describes the link to several top brand U.S. pet food companies.
Why not just skip Thai fish? Many would if that information was on the label, as it is with seafood meant for humans. But country of origin doesn’t apply to pet food rules. So where the fish or fishmeal is from isn’t likely to be announced on labels or packages. The difficulty tracking each link in the global seafood supply chain can even leave manufacturers in doubt. The article says bar codes on pet food in some European countries let consumers track Thai seafood to the packaging facilities. But prior to processing, the global supply chain for forage fish, much of which is used for pet and animal feed, is “invisible.”
Given the unsavory news, not to mention the topic of fishing the oceans to extinction, any amount of Thai fish is likely to be too much for many shoppers.
AAFCO, the governing (though not regulatory) body for the pet food industry notes that FDA pet food regulations “focus on product labeling and the ingredients which may be used.” Where those ingredients originate is left out.
That’s why some shoppers look for “alternative” certification labels from organic to Fair Trade, and put their faith in U.S. companies that aim to exceed regulatory standards. For example, Honest Kitchen, which sells human food-grade products, states on its website that suppliers guarantee their statement of country of origin. (Another promise is that no ingredient is from China.) The company is a member of Green America that promotes companies that operate in ways that support workers, communities and the environment.
As for buying dog food with fish sourced from non-Thai waters, some pet food companies do state where the fish is sourced. But many manufacturers have a long way to go to make the process transparent and easy enough for consumers to find their ingredient sourcing. (We highly recommend calling pet food companies and asking for this information to be more readily available!)
Advertising terms like “holistic” (meaning the whole is greater than the sum of the parts) and “biologically appropriate” (referring to meat-content for carnivores) say nothing about origin.
Even pet food regulators admit that pet caretakers “have a right to know what they are feeding their animals.”
So if in doubt where the fish is from, ask the company behind the bag or can. That much—the manufacturer’s name and address—is required on labels.
And some say, why should pet food buyers beware the global supply chain? With some research on a dog’s protein, calcium and other basic needs, it’s more possible than ever to get it right with a home-made diet rich in “human food” or even home-cooked table scraps. In fact, local food waste is a problem with plenty of solutions.
News: Guest Posts
Dog fed blue green algae supplement develops liver problem, report finds
July 23 2015
A new report by researchers at U.C. Davis points to the need for oversight of nutrition supplements. The pills and powders fed to pets to boost their health come with no assurance of getting what you pay for—or more than you bargained for, like toxic contaminants.
In this case, a tainted organic algae powder was damaging the liver of an 11 year old Pug, who lost her appetite and was lethargic after several weeks use. The authors say it’s the first documented case of blue-green algae poisoning in a dog caused by a dietary supplement. (Most reports of illness involve dogs exposed to water containing certain blue-green algae toxins.)
Blue green algae supplements are sometimes fed to dogs to relieve arthritis or boost the immune system.
Many consumers believe these products can only be sold if they are safe for use, the authors say. “Unfortunately, the opposite has been demonstrated in several studies showing the contamination of blue-green algae supplements with microcystins.”
With the use of commercial health products on the rise, the risk is growing. While supplements are regulated by the FDA, there are no requirements for proving them safe or effective before marketing. That is, the industry “is largely self-regulated,” the report says.
Toxic blue-green algae blooms occur in Oregon’s Klamath Lake, where supplement manufacturers harvest much of their source material. In 1997, the state became the first to regulate the amount of mycrocystins allowed in supplements.
Adrienne Bautista, the lead researcher on the current report, says in an email that the tests may not catch every problem. The tests many companies use to certify their products are below the 1 ppb Oregon limit are often ELISAs, Bautista says, which mainly detect “the LR congener of microcystin.” But there are more than 100 other congeners likely to have similar modes of action that the tests are “quite poor” at finding. So even if the supplement tests below the 1ppb for this common toxin, others may still be present.
What could lower the risk from these particular supplements is to produce the algae in a lab-like setting, Bautista says. “By harvesting it naturally, you have no control over contamination from other algae.”
The researchers call for stronger oversight of dietary supplements for companion animals, and greater awareness among veterinarians.
With treatment and by stopping the supplement, the Pug made a full recovery.
News: Guest Posts
Can be toxic to dogs
June 16 2015
Often, dogs are the first alert. Their willingness to swim in and drink slimy water makes them sentinels for some of the most powerful natural poisons on earth.
A Labrador Retriever enjoying a family outing in June collapsed after swimming in a Minnesota lake. He died that day at the vet’s office. Tests are pending but the vet suspects the dog was poisoned by cyanobacteria, also known as blue-green algae (BGA).
While most algae are harmless, some species of BGA produce toxins that can kill a dog within minutes. Those that survive, or dogs who are often exposed to low levels of toxins may develop health problems such as chronic liver disease, and possibly tumors; damage that may go unnoticed until it’s severe. Humans can be sickened, too, though deaths are rare.
Dog deaths are another matter.
As health agencies weigh the human risks that lie in recreational and drinking water from harmful algal blooms, they’ve been looking closely at animal deaths.
In New Mexico, 100 elk died last August after drinking water tainted with BGA. When it comes to pets, researchers suspect many deaths are missed because people don’t even realize their dogs were exposed. Vets may not recognize the symptoms, and tests to detect the toxins can be costly and complex.
A study published in 2013 found 368 cases of dogs that died or were sickened by BGA in the U.S. between the late 1920s and 2012. The authors say these “likely represent a small fraction of cases” in the U.S. each year. “The vast majority of BGA associated dog deaths remain unreported and often unrecognized by owners and veterinarians.”
And the cases have surged along with the number of toxic blooms fueled by nutrients such as phosphorous and nitrogen washed into waterways from agriculture, lawns and other sources—and by climate change.
Reports of canine poisonings were sporadic until the mid-1970s, when dog deaths attributed to BGA were reported “almost yearly,” the study notes.
In 2007, as drought plagued much of the country, the Minnesota lake region alone saw as many as 40 cases of canine algae poisoning, and at least four deaths. Since 2001, eleven dog deaths have been blamed on BGA in California’s Humboldt and Mendocino Counties.
The earliest known case in the U.S. was in the late 1920s when a dog swam in California’s Clear Lake during an algal bloom. The dog reportedly became ill after licking “a thick coating of algae” from its fur. In 2013, another dog sickened after playing in the lake was less fortunate... this dog did not survive.
Spotting Blue-Green Algae
There are plenty of clues for telling BGA— the most primitive group of algae—from harmless green, brown, and other kinds. But according to a fact sheet from the Humboldt County Health department, while most BGA blooms don’t produce toxins, only tests can tell. “All blooms should be considered potentially toxic.” Only “a few mouthfuls of algae-contaminated water may result in fatal poisoning.”
For one thing, its color isn’t always blue-green. It can also be reddish-purple or brown, and other hues. And not all blue-green species produce toxins, while the dozens that do are only toxic at certain times. Normally, algae are equally distributed throughout the water. But excess nutrients, heat and drought make for large blooms, followed by large die offs. As it decays, toxins are released. These can still taint the water after it looks clear. Blooms may last for a week; their toxins may last three weeks.
Even when BGA isn’t floating on the surface, it may lurk below, moving up and down with available light and nutrients. At night it often floats to the top, forming scum. So blooms can appear overnight.
Wind and waves can then concentrate toxic blooms in shallow areas or at the water’s edge—right where dogs like to splash, wade or drink. The water doesn’t taste bad, vets say, so dogs will lap it up. Some like to gobble down dried algae mats.
After the sudden death of a dog last July—hours after swimming in an Oregon reservoir—officials issued an alert, as they did in Minnesota. But toxic blooms and dog deaths were nothing new. According to Minnesota Department of Natural Resources, from 2004 through 2007, the state had reports of eight algae-related dog deaths, while toxic blooms are a familiar scourge at the Oregon reservoir.
At least 18 states have monitoring programs to detect harmful blooms. But sometimes, even advisories aren’t enough. After two dogs died within hours of drinking water from a private lake in Nebraska in 2004, state agencies acted quickly. Two weeks later, monitoring and notification networks were in place. But by the end of the recreation season there were reports of three more dog deaths, wildlife and livestock deaths, and more than 50 cases of human effects at Nebraska lakes.
The Environmental Protection Agency hasn’t set national standards for BGA toxins in recreational or drinking water, though scientists and some politicians are calling for them. This summer, the agency is promoting safety and public awareness to help protect dogs and kids.
While most algal blooms just make the water unappealing, an EPA information sheet says, “there are some real risks if dogs swim in, wade, or drink from water” with harmful algal blooms. The toxins “can sicken pets, causing everything from mild eye irritations and diarrhea to extreme health problems, including liver poisoning and even death.”
The EPA recommends that outings with pets to lakes, rivers and streams include an algae check. Dogs should not drink, swim or wade in water that is discolored, smells bad, or where there are mats of algae, foam or scum. If dogs do get into scummy water, rinse it off with tap water immediately, making sure they don’t lick algae from their fur. The toxins can also be absorbed through their skin. If a dog shows signs of poisoning, seek veterinary treatment right away. And report incidents to the Public Health Department. To avoid adding to the algae problem at home, the agency advises not over fertilizing.
According to the study of canine incidents, BGA toxins can be inhaled and ingested, and exposure can induce “acute, sub-acute or chronic poisoning” in animals and people.
Most reported dog deaths involved swimming in or drinking from lakes, rivers and other fresh waters where slime was visible. In California, BGA from freshwater tributaries drained into Monterey Bay, killing sea otters in 2010. Scientists were baffled by the deaths. They hadn’t known the toxins could reach the ocean. One major clue: suspicious dog deaths at a lake tainted with BGA that drains to the sea.
Other dog incidents may have involved beach outings. The study of canine cases says that between 2007 and 2010, at least 8 dogs developed serious or fatal liver disease after visiting Monterey-area beaches. Two of the dogs belonged to local veterinarians, but weren’t tested for the toxin that was killing sea otters.
Blue Green Algae Toxins & Treatment
Are water-loving breeds more at risk? Researchers warn that diagnosing algae poisoning is hard enough—such assumptions can lead to the wrong diagnosis. But the study did find that the most incidents involved Labrador Retrievers.
However, the “wide range” of affected dogs included Poodles, Dachshunds and toy breeds, which also encountered BGA in urban and residential water bodies. These waters, often shallow and stagnant in warmer months, can have high levels of nutrients escaped from nearby yards and gardens, “providing ideal conditions for toxic blooms.”
The belief that small dogs or urban-dwelling dogs don’t encounter algae may influence the diagnoses considered. Also adding to the problem of detection and treatment, the study claims: the tests are expensive and can take weeks, access to testing may be limited, and diagnosis may not be a priority for the owner after the dog has died.
According to an algae fact sheet from Humboldt County health department, the toxins of concern are nervous system poisons (neurotoxins) and liver poisons (hepatotoxins). The neurotoxins can kill animals within minutes by paralyzing respiratory muscles, while hepatotoxins can cause death within hours by causing blood to pool in the liver.
The canine study mentions the many reports of animals drinking algae-tainted water “and dying within hours from neurotoxicity or hepatotoxicity, or developing sublethal chronic liver disease.”
Another less dangerous compound causes allergic responses. But initial, low-level exposure to any of these toxins may cause skin irritation and stomach upset, the study says. So those symptoms alone may not help identify the toxin.
Both nervous system toxins and liver toxins can be fatal. Liver toxins cause weakness, vomiting, pale mucous membranes and diarrhea. Common signs of neurotoxins are muscle tremors, seizures, labored breathing and difficulty moving.
Often implicated in poisonings are anatoxins (neurotoxins) and microcystins (liver toxins, considered more common and possibly carcinogenic, research suggests). Dogs are especially susceptible to anatoxins, according to the North Carolina Department of Health’s website; these poisons can be fatal within minutes – or hours. Quick veterinary care with anti-seizure medication and oxygen may help.
The consensus is that there is no antidote for BGA toxins. But the review of dog poisonings says that most exposed animals aren’t given specific treatment, even though “simple, cost-effective treatments may improve their chances.” In the case of microcystin exposure, since many believe that no therapies exist, owners and vets “might euthanize suspect cases or provide limited supportive care.”
After several days of veterinary treatment, a Miniature Australian shepherd sickened by algae at a Montana lake was only getting worse. On the fifth day, her vets tried a new therapy not readily available. Last year, a report described what happened next as possibly the “first successful treatment of microcystin poisoning.”
Over the next few days the little Aussie made a surprising comeback.
After eight long days, that dog went home.
Wellness: Healthy Living
Simple preventive steps can go a long way toward offsetting their threats
June 14 2014
A few months ago, the icy breath of the north that normally tucks itself over the Arctic during the winter blasted into the Northeast, prime tick country. This prompted climate scientists to look for links between a weakened polar vortex and a warming world. But those who study arachnids were interested in other signs … like fewer ticks.
In January, Thomas Mather, PhD, an entomologist known to many as the “tick guy,” trudged through thick snow in Kingston, R.I., looking for the spot where he’d buried vials of deer ticks the day before. The overnight temperature had fallen to a tick-numbing three degrees. Locating the vials, he sprinkled the tiny black specks on his palm. They sat there like pepper. Then they began to move.
For ticks, it seems, the ice age was a snowbird’s vacation. So don’t drop your guard, warns Mather, director of the University of Rhode Island’s Center for Vector-Borne Disease and its outreach arm, the TickEncounter Resource Center (TERC). Mather has spent two decades studying the rise of the blacklegged tick—commonly called the deer tick—in Rhode Island.
“I’m pretty certain that we won’t really be able to credit winter’s serial polar vortices for whatever the ticks are or are not doing in the spring,” he says. It’s not about the weather, but cycles. In their two-year lifespan, ticks feed on the blood of hosts during three growth stages: larval, nymphal and adult. According to Mather, the deer tick problems we’re facing in 2014 were largely decided last August and September by the number of larval ticks that found infected rodent hosts. “That will determine both the summer nymph populations and fall’s adult tick abundance,” Mather says.
In recent years, those cycles have produced record numbers of nymphs at the sites his team sample each summer. So many, in fact, that he considers it a public health crisis in his state, which is part of the East Coast “tick-belt.”
Mather says that human and pet encounters with ticks are skyrocketing, and while ticks don’t always carry a disease, they may, and many of those diseases are dangerous.
Between 2006 and 2010, Veterinary Week reported a 30 percent increase in the rate of dogs exposed to tick-transmitted diseases. Among them: The aggressive lone star tick can transmit ehrlichiosis, one of the most common and dangerous tick-borne diseases in dogs. The brown dog tick and American dog tick also spread ehrlichiosis, babesiosis and Rocky Mountain spotted fever (RMSF).
Then there’s the deer tick. Although there are hundreds of species of ticks—all of which are relatives of spiders and mites, in the U.S. —the deer tick is number one on the most unwanted list. It spreads several dangerous infections, Mather says, and topping that list is Lyme disease.
Trail of Infection
The deer tick in the East and the related western blacklegged tick are the only known transmitters of Lyme disease in the United States. The trail of infection typically begins with rodents or, in the West, lizards, natural reservoirs of the Lyme bacterium, Borrelia burgdorferi. Ticks need a blood meal to reproduce, and acquire the bacterium when they bite an infected host. The next time they bite, they inject the bacterium into their unlucky meal source.
Where Lyme is found, so are deer, but the “deer tick,” as it’s commonly called, is actually the blacklegged tick, and it feeds on many different mammals, birds and reptiles. This tick has been on a tear in the Northeast, its range expanding, its pathogens mutating, ever since the disease it spreads—long known in Europe—was recognized in 1975 in Lyme, Conn.
Lyme disease was first diagnosed in a dog about 25 years ago, and now it’s one of the most common tick-borne diseases in dogs in the U.S., notes Cornell University’s Baker Institute for Animal Health. In several of the most affected states, one out of 15 dogs tested positive for Lyme disease in 2011, according to a study by the Centers for Disease Control and Prevention (CDC). And where dogs test positive, so do humans. In 2012, 95 percent of human cases were reported from 13 states concentrated in the Northeast and upper Midwest.
In parts of the Northeast, up to half of the deer ticks are infected with Lyme disease. In California, where Lyme also exists, the infection rate is far lower, with the disease mainly occurring in four northwestern counties.
A dog’s risk in such areas goes up and down. As noted on the Baker Institute’s website, even within highly infected regions, there are “hotspots of tick infestation and Lyme disease risk,” which “mingle with non-infested areas with much lower risk.” Even so, far fewer infected dogs than people develop the disease. Studies suggest that more than 75 percent of dogs in hyperendemic areas may be exposed to infected ticks, yet only about 5 percent develop Lyme. However, Lyme is only one of the diseases deer ticks spread to dogs; among the others are ehrlichiosis, babesiosis and anaplasmosis (“dog tick fever”).
There’s also a growing list of new diseases involving deer ticks, including one caused by the bacterium Borrelia miyamotoi, which mimics Lyme disease, and the rare but increasing Powassan virus and its variant, deer-tick virus. Powassan hasn’t been found in dogs, but dogs with neurological issues aren’t commonly tested for this rare disease, and such tests aren’t readily available.
In fact, even with available tests, diagnosing Lyme disease in dogs is challenging. Unlike viral diseases such as Powassan, Lyme is a bacterial infection and can be treated with antibiotics. But its symptoms, if any, mimic many other diseases. One common sign, lameness, takes two to five months to appear, according to the Baker Institute, and, unlike people, dogs don’t develop the telltale bull’s-eye rash around the bite.
A CDC study found that people in areas with a higher-than-average number of dogs with Lyme disease are at greater risk of getting it themselves. There’s no evidence that dogs spread it directly, but they may bring infected ticks into homes and yards.
And since dogs have a way of getting people outside, down that trail and—bag in hand—under that bush, it’s easy to see why the CDC says that dog owners face an elevated risk for Lyme disease.
Know the Enemy
Going outdoors is not the problem. What increases the risk of being infected is entering tick habitats. Especially if you go in thinking that ticks fall off trees. Or that they pounce, or fly. Surveys find that most people don’t know enough about ticks and their habits to ward them off.
“When it comes to tick-bite protection and disease prevention, we’ve learned that people tend to only focus on it after the fact,” Mather says.
That’s why TERC, which Mather heads, came into existence. Its goal is to entice people to learn more than they ever wanted to know about Ixodes scapularis (blacklegged or deer ticks)—ticks that carry the Lyme disease pathogen—and other species as well.
The idea for TERC began around 2004, when Mather decided to start “an aggressive, grassroots, tick-bite prevention program.” The tally wasn’t nearly as appalling back then, but by 2013, CDC estimates of the number of Americans diagnosed with Lyme disease each year hovered around 300,000, a whopping 10 times higher than anyone thought.
Although Mather felt that scientists already had solutions, “the link between science and people’s lived experiences with ticks was largely missing.” To fill this gap, his team took their fieldwork in a new direction: into tick-afflicted neighborhoods and to meetings with stakeholder groups. “People kept asking if we had a brochure or website,” he says. “After hearing that, oh, like 50 times, we started brainstorming.” They knew that brochures usually end up in the trash, but could a website reach people? “TickEncounter is what we came up with,” he says. It launched in 2006.
Today, the Internet teems with tick-related websites and information, and Mather believes it’s more important than ever to promote “a common core message” so the facts are clear to people. TickEncounter aspires to be the place people turn to for reliable and up-to-date information. The site isn’t soft on the facts; many people are susceptible, even likely to fall victim to tick-borne disease, which can be devastating. But simple preventive behaviors work. Before people can take action, Mather says, they need to believe in their own ability to successfully use those practices.
TERC’s unique graphic interface empowers users to snitch on the tiny army, ratting on its whereabouts and force-strength by season and region. The TickSpotters program, which includes crowd-sourced surveillance, recently added veterinary clinic reporting. Every two weeks, participating clinics send in patients’ ticks for identification. “These data are informing our ‘Current Tick Activity’ databases,” he says. Posts are updated every two weeks for nine U.S. regions. They plan to add an online dashboard with a map of results to show tick trends across America.
In February 2014, the TickSpotters page reflected the effects of the frigid weather, showing low tick activity in New England. Things were heating up on the West Coast, however, home to the western blacklegged tick. In fact, it’s always tick season somewhere, and people and pets can get Lyme disease even in winter.
“Pet owners seem most [affected] by adult ticks because they can see them,” Mather says, but the nymphs “are potentially more dangerous.” Nymph season is May through August, months during which people and dogs tend to spend the most time outside. Nymphs lurk in moist leaf litter in or near the edge of wooded areas. Because they’re so tiny at this stage, nymphs attach to small mammals near ground level, such as mice, which often carry Lyme. According to the Baker Institute, only repeated exposure to nymphs causes infection in dogs.
Adults, being larger, tend to bump into their hosts at higher altitudes. They wait aboard grasses and bushes, closest to animals’ largest body surface. They’re mainly a threat to dogs in fall and early spring. In winter, they only seek hosts when temperatures rise above freezing. Adults also transmit Lyme, babesiosis and anaplasmosis.
Despite the threats ticks pose, it’s not easy designing public education programs that work for everyone, health officials say. The problem is different for places in which ticks are entrenched and those with an emerging infestation. The bad news is, the number of the latter is definitely growing.
More Ticks, More Diseases
According to the U.S. Geological Survey, the temperate, humid, northeastern U.S. is a favorable place for ticks. More so all the time, it seems.
Ninety percent of canine Lyme cases now occur in the Northeast, according to the Companion Animal Parasite Council, whose website includes a “parasite prevalence” map by state, with confirmed canine cases by county. Lyme disease has also shown up in Northern California and on the Oregon coast, but there isn’t much evidence of spread.
The deer tick has even moved into Canada, where average temperatures have increased by 2.5º F over the past 60 years. One study suggests that tick-inhabitable regions in Eastern Canada will expand from 18 percent to more than 80 percent by 2020.
A 2013 study by researchers at the University of Toronto found that in the U.S., Lyme disease is shifting northward; the study noted large increases in 21 states between 1992 and 2007. This may be due “at least in part to the effects of climate change,” wrote the researchers. A Yale study also found links between Lyme disease outbreaks and milder weather in the Northeast. The 2004–2007 survey found the greatest risk in southern Maine through Washington, D.C., Minnesota and Wisconsin. Newer hotspots appeared to be cropping up in Illinois, Indiana, Michigan and North Dakota.
Warmer winters, which allow ticks to breed throughout the year, may be a factor, the researchers say. Warm, moist air may also extend their life cycle. They dismissed the Southeast as a location for Lyme disease, only acknowledging the lone star tick. But some say there’s growing evidence of a Lyme or Lyme-like infection there, too. In North Carolina, Lyme disease is up slightly, with a few cases diagnosed per year, but other diseases are being reported. RMSF cases rose 50 percent in 2012 compared to 2011. In June 2013, a child died from RMSF.
In 2009, the Ixodes affinis tick, native to South America and previously seen only in coastal Florida and Georgia, was found in North Carolina. Recently, the more southerly Gulf Coast tick, which transmits canine hepatozoonosis, was spotted there as well. This disease affects muscle cells and results in a debilitating and usually fatal condition. The aggressive lone star tick, historically found in southern and south-central states such as Texas and Florida, has been marching north and east for decades, scientists say. It has even worked its way into Maine and Ontario, Canada.
According to the CDC, cases of RMSF, mainly found in the Southeast, cropped up in an area of eastern Arizona where it had never before been seen—mostly in communities with many free-roaming dogs, who likely carried the brown dog tick. Newer deer tick pathogens are expanding their range, as well.
Many things are tipping the balance, scientists say, and they’re all wrapped together. They include the prevalence of deer, invasive plants, bird migration and traveling pets. Then there’s the sprawl of suburbs into woodlands, which exposes more people and pets to tick-borne diseases.
Some point to dwindling biodiversity, as animals that keep tick numbers down are increasingly shut out of their habitats by development and other human activities. Though ticks aren’t known to be any animal’s food source, opossums—rarely welcomed in the suburban landscape—groom themselves meticulously, and in the process, kill ticks by the thousands. As Rick Ostfeld, senior scientist at the Cary Institute of Ecosystem Studies, remarked, “Many ticks try to feed on opossums, and few survive the experience.”
Warmer weather and drought may be causing oaks to overproduce acorns some years, creating a boom in the white-footed mouse population. More acorns, more mice; more mice, more ticks. When the acorn crop crashes, fewer mice reproduce, and ticks are driven to seek fresh blood.
Some scientists think ticks migrate, following animal hosts that may be moving with the shift of plants.
And they may find perfect habitat in a dog’s backyard.
Tools to Stem the Tide
Farmers who take a sustainable approach often use a technique known as integrated pest management (IPM) to control pests and avoid toxic chemicals. Pet owners can learn from these farmers’ practices, which combine a range of methods and as few synthetic chemicals as possible. The U.S. Environmental Protection Agency’s website describes IPM as “an effective and environmentally sensitive approach” that can be applied in homes and gardens.
In fact, surveys find that homeowners in suburban neighborhoods in the Northeast are reluctant to spray chemicals to kill ticks. And at any rate, ticks are adapting to traditional pesticides. A recent CDC study found that spraying bifenthrin in a suburban area failed to reduce tick bites. Homeowners do widely accept methods such as brush and leaf-litter control or landscape barriers, which experts say offer medium levels of control.
TERC doesn’t rule out pesticides to control deer ticks, but suggests careful targeting to limit their use. Their recommended approach combines host-specific “Tick Tubes” and habitat-specific perimeter sprays. They also discuss many other ways to keep ticks in check, including their web-based TickEncounter Risk Calculator. By answering questions about their landscaping and other factors, people can use it to help determine the risks their yards offer, and can receive customized action plans.
At a 2013 EPA conference on tick-borne disease and IPM, Mather discussed his work, including the top protective actions people can take. Among them are knowing the ticks in your area and how to identify their life stages and seasonal patterns; taking protective actions, such as daily tick checks; and, of course, including pets in the plan. Even when a tick finds a dog, it has to be embedded for 24 to 48 hours to spread infection; quick removal drastically reduces the risk. TERC is also working on a vaccine for people, pets and wildlife.
So, the key to successful tick control lies in your own back yard, where about 75 percent of tick bites are said to occur. Seeing one tick is not enough to launch weapons. Signs of deer near your home, though, may be an important clue. To discourage ticks and their hosts, mow regularly, remove weeds and leaves, and make sure garbage and composting containers are rodent-proof. Prevention might also mean removing exotic vegetation or other welcoming habitat. Invasive bush honeysuckle and Japanese barberry, for example, attract white-tailed deer and mice (and thus, their ticks), a study found. Managing the growth of these plants significantly reduced the abundance of infected ticks. Paving or laying down gravel in heavily used areas also helps limit tick turf.
There is no one perfect solution to what seems to be nature's new normal. Come heat or hail, ticks are on the march. As summer unfolds, they’re sure to be out in force, seeking the most inviting habitats and hosts. Dog owners just have to think more like farmers … and tick guys.
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