Popularized as a panacea for pruritus, an answer to allergies, a guardian for the gastrointestinal tract, grain-free diets were once the darlings of the dog food aisle. Then 2014 happened… and reports started to trickle in to the FDA of nonhereditary dilated cardiomyopathy (DCM) in dogs caused by eating certain commercial pet foods, many of which were labeled “grain free.”

As cases mounted, the FDA announced its pledge to investigate, and sales of grain-free canine diets crumbled. Yet today, grain-free bags and cans decorate store shelves, ride checkout conveyor belts and fill kitchen pantries.

In the last year, pet foods labeled as grain-free have seen 5% sales growth, said Danielle Conway, DVM, while presenting a session at the Fetch Coastal conference in Atlantic City, NJ. She also noted that revenues are predicted to hit $53 billion over the next decade.

Clearly, there was a shift in the collective attitude toward grain-free canine nutrition. But to digest it requires an understanding of the science behind the probe.

DCM, heart chamber dilation secondary to cardiac muscle wasting, occurs genetically in breeds like Doberman pinschers, boxers, great Danes and Irish wolfhounds

; a separate link between DCM and taurine deficiency has been described in golden retrievers

. But the cases that turned FDA heads involved dogs that didn’t match recognized breed criteria, and were seemingly nonhereditary.

By 2018, more than 300 case reports of nonhereditary DCM had landed on the FDA’s doorstep: The common thread for many was diets devoid of grain.

 Their recipes swapped cereals like wheat, rice, corn, millet and rye for higher-than-usual proportions of such ingredients as legumes—or “pulses” (peas, lentils and beans)—and potatoes.

In response to the alerts, the agency announced an investigation. As word spread, people stopped feeding grain-free formulations to their pets. Within a year, the FDA had received a running total of more than 500 records for affected dogs (plus reports for 9 sick cats), which included a wide variety of commercial foods.

 “That’s a whole lot of patients and a whole lot of diets out there,” Conway said.

In mid-2019, the FDA named the top 16 brands of grain-free recipes appearing in these canine DCM case reports.

 But the agency fell short of panning grain-free altogether.Instead, they stated that nonhereditary DCM is spun by a complex interplay of genetics, diet and underlying medical conditions.

If owners were quick to turn their back on grain-free diets after learning of the FDA’s scrutiny, they were even hastier to reject 

 in the first place. That’s because pet food choices tend to follow human diet trends, Conway explained. "It’s the belief that less grain, less gluten and less sugar is a healthier person. And we project this onto our animals,” she said.

Glutens have come under fire, and indeed there is the occasional dog with a celiac-like sensitivity to gluten. (Inherited gluten sensitivity has been documented in Irish setters

) But just as nutrition trends in people become broadened to include dogs, gluten gets generalized to encompass grains.

However, Conway pointed out, not all grains contain gluten. But some do. And pet owners typically do not know the distinction.

Grain-free pet foods exploded in popularity in the early 2000s, for their being sansgluten and, in consumers’ eyes, free of other 

 as well. But seasonal allergies are often mislabeled as food allergies, which are uncommon and usually directed against protein sources.

 These allergenic proteins, Conway clarified, are present at higher levels in meats than in grains.

Many people also consider grain-free rations to be low in carbohydrates and, therefore, closer to the ancestral diet of the wolf. Carbohydrates are generally seen as little more than cheap fillers, devoid of nutrients and full of calories.

“Carbohydrates seem to be the macronutrient being vilified at the moment,” she said.“But carbs are so much more than just sugars and starches.”

Carbohydrates power the body. They can be simple - white rice, pasta and plain old sugar… rapid-fire fuel injectors. But those complex cousins, things like whole grains, legumes and vegetables, should not be forgotten. These carbs are healthy sources of fiber and protein, and release glucose at a more measured pace.

Regardless, eliminating grain hardly solves the carbohydrate problem: Ingredients like potatoes, chickpeas and lentils are often used as stand-ins for deleted grains in commercial foods. This is particularly true for kibble, which requires sufficient carbohydrate binder to hold it together.

Pet nutrition is indeed complex. Conway said owners look to the veterinary community for information. She referenced a 2003 American Animal Hospital Association (AAHA) study that found 90% of clients expect nutritional recommendations during their clinic visits, but only 15% leave feeling they have one in hand.

As for the clinicians, perhaps food talk drags appointments out too long. “Nutrition conversations are time-consuming,” she conceded.

But critical, nonetheless. Especially to counteract the hapless hype that abounds on social media, where folks who are neither veterinarians nor nutritionists dish out feeding directives. “These are the people our clients are going to because they don’t feel they are getting the information from us,” she said. “So, there is a lot of misinformation being spewed out there.”

As omnivores, all canids are adapted to eating grain. But there are some scientifically proven reasons why some dogs might experience adverse effects from grain consumption.

Gluten-containing cereals, wheat in particular, contain amylase/trypsin inhibitors, which have been implicated in various types of inflammation.

 Other wheat compounds, including lectins and amylopectin, also possess proinflammatory properties.

 Inflammation can set any body system on fire, with the gastrointestinal tract and skin particularly vulnerable.

Modern, domestically produced commercial grains differ from 

 lines of yesteryear and from varieties grown abroad.

 Higher levels of gluten and amylopectin, Conway said, could play into the food sensitivities to which U.S.-grown grains have been linked.

The FDA now advises owners to defer to their vets if considering making the switch from a traditional diet. But their apparent flip-flop on grain-free feeding is hardly a roadmap for veterinarians trying to advise clients on pet nutrition.

Although ingredients matter, Conway said, they are not everything. “You could make a really horrible grain-inclusive diet, and a really great grain-free diet. It depends on how it’s formulated.”

She said good nutritional choices hinge on brand scrutiny, and she encourages the veterinary community to mentor owners in evaluating manufacturers on things like feeding trials, digestibility studies and overall quality control.

“I don’t think we necessarily have to recommend avoiding grain-free,” she said, “but we should recommend the companies we trust.”

Grain-Free Pet Food Market Outlook, 2022-2032

. Future Market Insights, Inc. Newark, De.

Freid KJ, Freeman LM, Rush JE, et al. Retrospective study of dilated

Kaplan JL, Stern JA, Fascetti AJ, et al.Taurine deficiency and dilated cardiomyopathy in golden retrievers fed commercial diets.

 2018;13(12).doi:10.1371/journal.pone.0209112

Basili M, Pedro B, Hodgkiss-Geere H. Low plasma taurine levels in English cocker spaniels diagnosed with dilated cardiomyopathy. 

United States Food and Drug Administration. FDA investigating potential connections between diet and cases of canine heart disease. July 12, 2018. Accessed December 14, 2023. 

https://wayback.archive-it.org/7993/20201222194256/https://www.fda.gov/animal-veterinary/cvm-updates/fda-investigating-potential-connection-between-diet-and-cases-canine-heart-disease

United States Food and Drug Administration. FDA investigation into potential link between certain diets and canine dilated cardiomyopathy. June 27, 2019. Accessed December 14, 2023. 

https://www.fda.gov/animal-veterinary/outbreaks-and-advisories/fda-investigation-potential-link-between-certain-diets-and-canine-dilated-cardiomyopathy

Garden OA, Pidduck H, Lakhani KH, et al. Inheritance of gluten-sensitive enteropathy in Irish setters. 

2000;6(4):462-468. doi:10.2460/avjr.2000.61.462

Vaden L, Sellon RK, Melgarejo LT, et al. Evaluation of intestinal permeability and gluten sensitivity in Soft-Coated Wheaten Terriers with familial protein-losing enteropathy, protein-losing nephropathy, or both. 

2000;61(5):518-24. doi:10.2460/avjr.2000.61.518

Mueller RS, Olivry TT, Prélaud P. Critically appraised topic on adverse food reactions of companion animals: Common food allergen sources in dogs and cats. 

2016;12:1–4.doi: 10.1186/s12917-016-0633-8

Gaschen FP, Merchant SR. Adverse food reactions in dogs and cats. 

2011;41:361–379. doi:10.1016/j.cvsm.2011.02.005

Suto A, Suto Y, Onohara N, et al. Food allergens inducing a lymphocyte-mediated immunological reaction in canine atopic-like dermatitis. 

2015;77:251–254. doi:10.1292/jvms.14-0406

Arendt M, Fall T, Lindblad-Toh K, Axelsson E. Amylase activity is associated with 

 copy numbers in dog: implications for dog domestication, diet and diabetes. 

. 2014;45(5):716–722. doi:10.1111/age.12179

Junker Y, Zeissig S, Kim SJ, et al. Wheat amylase trypsin inhibitors drive intestinal inflammation via activation of toll-like receptor 4. 

. 2012; 209(13):2395–2408.doi:10.1084/jem.20102660

De Punder K, Pruimboom L. The Dietary Intake of Wheat and other Cereal Grains and Their Role in Inflammation. 

2013; 5(3):771–787.doi:10.3390/nu5030771

Articles

In the years since experts began hashing about the possible heart hazards of grain-free dog food, thinking has changed. But conclusions remain few, leaving pet owners and their veterinarians to chew on the dilemma.  

Still seeking a grain of truth

Learn how veterinary diagnostics have changed

The evolution of in-house diagnostics

Okay, friends, let's get into it. We're going to talk about Zoetis Diagnostics and improve patient outcomes. I want to start off by discussing the importance of in-house diagnostics. Dr. Wolfe, what has this experience been like for you from where we were say, years ago to where we are now?

Well, you know, I started this career as a veterinary technician in 1999. And the practice still had a QBC machine. And at that time, we were doing beta testing for what's now known as the 40X. And then in veterinary school, I worked in clinical pathology around rather large machines. And when I started my first career in 2005, at a much more scaled down version of hematology and chemistry—still did a urinalysis via the dipstick—and over time now we've got the machine that reads the dipstick. We now have the SediVue to analyze the cellular debris. We have multiple rapid tests available now. We have coagulation; we have we have critical care. And then now with the Imagyst, we now have artificial intelligence to be able to run our fecal samples and our cytology's on and receive data in as little as 12 minutes to as long as two hours for send out pathology reviews.

That's really neat. And Dr. Clary I'm sure it's come such a long way to where we are now in your practice, right?

Yes. The QBC, I had one that was called a Reflotron, and you know, I can remember on Sunday mornings being up there doing my test by myself. And you know, you weren’t really confident in it. With the Zoetis products, I feel really confident like with the Imagyst. I love it because I've got somebody that's board-certified, backing me up on what I might be thinking versus what they really know. And it's really a game changer for my confidence and the way I practice. That's been my biggest advantage. 

Yeah and the footprint of these has really gotten smaller as well, where space is precious in a veterinary clinic. These machines now are very small and don't take up much room in the lab as well, so...

I would say space is a commodity in vet med for sure.

Videos

Veterinarians share how Zoetis’ Vetscan Imagyst has improved their patient outcomes and practice efficiency by using artificial intelligence for fast and reliable results

The evolution of in-house diagnostics from QBC® to Vetscan Imagyst®

Meet the panel who will discuss AI diagnostics

Meet the Zoetis diagnostics experts

Hey everyone. Great to see you all here for another dvm360 Pet Connections panel discussion proudly sponsored by Zoetis. In this dynamic conversation, we'll discuss the power of innovation and collaboration in veterinary medicine where Zoetis is leading the way towards a future of enhanced care and better outcomes for our furry companions. I'm your moderator, Dr. Adam Christman, Chief Veterinary Officer here for dvm360, and I'm thrilled to introduce today's panelists. Joining us over here is Dr. Cory Penn. Dr. Cory Penn received his DVM from the University of Missouri College of Veterinary Medicine following his Bachelors of Science from Eastern Illinois University. Before joining Abaxis and Zoetis, Dr. Penn was a small animal veterinarian and medical director in central Illinois. He joined Abaxis Global Diagnostics in 2016 as a professional services veterinarian for the central and western United States and after the acquisition of Abaxis held the same role with Zoetis Diagnostics. Dr. Penn is currently the Senior Veterinary Diagnostic Platform Lead for VETSCAN IMAGYST with Zoetis Global Diagnostics. Dr. Penn currently resides in the Midwest with his wife Emily, three daughters—Harper, Reese, and Charlotte—Labrador Retriever Chloe and his cats Fluffy and Pinky. In his free time, Dr. Penn enjoys spending time with his family and being outdoors. Also with us is Dr. Lisa Hann. Dr. Lisa Hann decided to bring global adventure to her veterinary education by pursuing both undergraduate studies and her Doctorate of Veterinary Medicine Degree at St. George's University in Grenada and completing her clinical year at the University College Dublin. Dr. Hann also volunteered at a mixed animal practice in India and a zoo in Costa Rica during her schooling. After these travels, Dr. Hann pursued a rotating internship in New York City, during which she fell in love with internal medicine. She followed up her internship with a residency in small animal internal medicine at the University of Pennsylvania. During her residency, Dr. Hann was involved in hematology and transfusion medicine research. Prior to joining the consultation team with Zoetis, Dr. Hann worked for a decade at specialty and emergency referral hospitals with a very busy and varied caseload in both Seattle and New York City. Dr. Hann enjoys all aspects of the challenging and ever-complex world of internal medicine. However, she is especially interested in gastrointestinal diseases, endocrinopathies, immune-mediated processes, and hematologic disorders. Dr. Hann looks forward to partnering with veterinarians in case discussion and collaborating to develop intelligent and approachable diagnostic and treatment plans for patients and clients. Dr. Hann currently resides in Seattle with her husband, a kidney donor orange tabby cat named Penne Pasta—love it—and a rambunctious Chow Chow named Gimli. Also joining us as our wonderful friend and colleague, Dr. Carl Clary. Dr. Clary has been practicing veterinary medicine for over 25 years and is highly skilled at performing orthopedic surgical procedures. He is exceptional at performing knee CCL repairs, hemilaminectomy, and ventral slot surgeries, bone fracture repairs and more. His veterinary interests include orthopedic surgery, theriogenology, and internal medicine. When he's not practicing Dr. Clary enjoys being outdoors, racing, welding, and spending quality time with his wife Petra and their two children Gage and Portia. And also we have Dr. Shelli Wolfe that's here. Dr. Wolfe has been practicing in Lubbock, Texas since graduating from veterinary school at Texas A&M in 2005. Her veterinary interests include feline medicine, dentistry, internal medicine, and ultrasonography. Dr. Wolfe is very thorough in her practice of medicine and excels at working up complex cases. Outside veterinary medicine, she enjoys being a wife and mother to her husband, Matt and their two children, Reese and Logan. They are avid baseball fans and enjoy attending baseball games, especially the Texas Rangers. So I guess go Rangers, right?

Get to know four veterinarians with diverse backgrounds and interests as they share their experiences on how to provide enhanced care and better outcomes for pets

Meet the panel of Zoetis Diagnostics experts and practicing veterinarians 

The FDA issued 9 warning letters to manufacturers and distributors, citing unapproved and misbranded antimicrobial animal drugs in violation of federal law. According to the FDA,

 warning letters were issued to the following companies:

The FDA has requested these companies provide a response to the warning letters within 15 days of receiving them, outlining their plans to rectify the violations mentioned. Failure to promptly address these violations may lead to legal action by the FDA, which could involve product seizure and/or a court order mandating the cessation of manufacturing and distribution of unapproved products by the company.

The agency's apprehension stems from the risk of antimicrobial resistance, since the usage of these drugs without medical supervision could potentially increase this resistance.

 Antimicrobials are pharmaceuticals that kill or curb the growth of microorganisms. This makes them critical tools for preventing and fighting diseases in both people and animals. However, antimicrobial resistance occurs, it threatens public or animal health by making it difficult or impossible to treat the diseases caused by these microorganisms.

The marketed products are not the subject of a “New Animal Drug Application” from the FDA, nor are they conditionally approved or on the Index of Legally Marketed Unapproved New Animal Drugs for Minor Species, which are the main legal pathways for animal drugs to reach the marketplace. As a result, their safety and effectiveness have not been authenticated by the FDA through the animal drug review process or facility inspections.

The animal products mentioned in the warning letters are marketed and labeled for minor species such as aquarium fish and pet birds. They contain antimicrobials that are important in human medicine, such as amoxicillin, penicillin, tetracycline, and erythromycin, and are being illegally marketed over the counter.

“These unapproved animal drugs pose a two-fold risk to public health,” said Tracey Forfa, JD, director of the FDA’s Center for Veterinary Medicine, in the release. “First, these products haven’t been through the FDA drug review process, and we don’t know whether they’re safe or effective, or even contain what the label states. Second, inappropriate use of medically important antimicrobials contributes to the development of antimicrobial resistance, which affects both human and animal health.”

For consumers worried about products mentioned in the warning letters, the FDA recommended that they be safely disposed of and report any adverse events associated with these products to the FDA’s Center for Veterinary Medicine.

Additionally, the FDA would like to remind the public that all approved animal drugs containing these antimicrobials are only legally available by prescription from a licensed veterinarian. The administration stressed that providing animals with the appropriate drug is more likely to effectively resolve infections and reduce the need for extended treatment with antimicrobials.

FDA Warns Nine Manufacturers, Distributors of Unapproved Antimicrobials for Animals. News release. US Food and Drug Administration. December 14, 2023. Accessed December 14, 2023. 

https://www.fda.gov/news-events/press-announcements/fda-warns-nine-manufacturers-distributors-unapproved-antimicrobials-animals

Antimicrobial use and antimicrobial resistance. American Veterinary Medical Association. Accessed August 2, 2023. 

https://www.avma.org/resources-tools/one-health/antimicrobial-use-and-antimicrobial-resistance#:~:text=Antimicrobials%20are%20used%20to%20prevent,including%20via%20feed%20or%20water

Nine manufacturers and distributors received warning letters with concerns about federal law violations

FDA issues warnings of unapproved antimicrobial animal drugs

gives an overview of the technology used in cardio monitoring and how to troubleshooting concerning numbers

Cardiovascular monitoring reminders for technicians

While at the Fetch conference in Long Beach, California, Erica Brandt, CVT, VTS (ECC), hospital director of WestVet in Meridian, Idaho, sat down with 

 in an interview and shared her thoughts on veterinary cardiology technology and how veterinary technicians can become more comfortable and confident with using these devices/machines. She also gave her advice for dealing with abnormal numbers and reminded technicians to keep in mind that a patient's "normal" might not be exact to the textbook's normal.

The following is a partial transcript of the video.

 The technology in cardio monitoring has come a long way in human medicine. I think the thing that we need to remember in veterinary medicine is that we need to know how to use the technology that we have, and use it very well. So something like blood pressure monitoring, something like ECGs, do we need to advance to the level that human medicine is at? Maybe not. Maybe we just need to go back and be very confident, very comfortable, and understand what our blood pressure monitoring is telling us and how to get the best blood pressure monitoring.

The biggest thing that I would tell a technician when troubleshooting abnormal numbers, is know what is normal. But not only know what is normal pertaining to the textbook, but know what is normal for your patient.

Erica Brandt, CVT, VTS (ECC), gives an overview of the technology used in cardio monitoring and how to troubleshoot concerning numbers

A new annual list of the top toxins for pets includes marijuana for the second consecutive year. Created by the Pet Poison Helpline using case data, the 2023 Top Pet Poisons list also features rat poison, a pain medication, and some more commonly known animal toxins.

Pet Poison Helpline is a toxicology resource that office guidance for all species. Incident cases for dogs account for 88% of the hotline’s calls, and 11% of calls are feline-related. The remaining cases involve other species, including birds, small mammals, large animals and exotic animals.

The 2023 case data shows chocolate as the No. 1 toxin for all species in 2023. The sweet treat for humans also topped the Top 10 toxins list for dogs and was the second-most common poison for cats. “Even though it is widely known that pets shouldn’t consume chocolate-containing products, they constantly find a way,” said Renee Schmid, DVM, DABT, DABVT, a senior veterinary toxicologist for the helpline, in an organizational release.

Signs of chocolate poisoning in pets include vomiting, diarrhea, hyperactivity, restlessness, increased thirst, hyperthermia, tremors, abnormal heart rhythms, elevated heart rate, and hypertension.

Marijuana and carprofen first appeared on the annual year-end list in 2022, and both were again among the Top 10 Pet Poisons for all species this year. In the 2023 case data, marijuana-related incidences accounted for the sixth-highest toxin overall for pets and was also No. 6 for dogs.

“As more states legalize medical and recreational cannabis, the more marijuana-related calls we are receiving. Interestingly, dogs seem to be much more attracted to marijuana, as cannabis didn’t make the feline Top 10 list,” said Schmid in the release.

Clinical signs in pets poisoned by marijuana can often be seen within minutes to hours, depending on whether the animal was exposed through inhalation or ingestion. Signs of poisoning include a dazed expression, glassy eyes, incoordination, slow response times, dribbling urine, vomiting, drooling, changes in heart rate, vocalization, neurological stimulation, hyperactivity, or coma.

Carprofen is an FDA-approved prescription pain-relief product indicated only for dogs. It is a nonsteroidal anti-inflammatory drug, commonly used to manage osteoarthritis and inflammation, that is safer when administered at therapeutic dosing levels.

Toxic amounts of carprofen can lead to severe gastric ulceration and acute kidney failure in dogs and cats. Common signs of toxicity include vomiting, diarrhea, bloody vomitus, black-tarry stool, inappetence, lethargy, an increase in urination or thirst, malaise, and abdominal pain. Liver damage and seizures may also occur and death is associated with extremely high levels of exposure.

“When we broke down the overall Top 10 Pet Poisons list by cats and dogs, we found some toxins that are specific to each,” she added.

 The 2023 most common toxins for each species is as follows:

Onions/Chives/Leeks/Shallots (Allium species)

Alstroemeria, Peruvian lily (Alstroemeria species)

“Cats are incredibly attracted to plants and flowers, particularly lilies,” Schmid said in the release.

 “Three different varieties of lilies appear in our feline Top 10 list, which also includes tulips.”

It is critical for clients with cats to know which lilies are toxic to these felines. Common toxins include Oriental hybrid lilies, roselily, Star Gazer and Casa Blanca lilies, which are often found in cut-flower bouquets. Potted Easter lilies, garden plants such as Asiatic and tiger lilies, and daylilies—which is not a true lily—may also cause kidney failure in cats.

Exposure to any part of the plant, including leaves, flowers, pollen, or even the water from the vase may result in acute kidney failure in cats, according to Pet Poison Helpline. These ingestions are medical emergencies and require immediate veterinary care such as early decontamination, aggressive intravenous fluid therapy, renal function tests, and supportive care to greatly improve the cat’s prognosis. Although dogs may experience minor gastrointestinal upset after ingestion of these lilies, they do not appear to develop kidney damage.

 on our website that helps pet lovers identify potential toxins and provides common symptoms. If you are concerned about something your pet has come in contact with, or has ingested, contact your veterinarian or call us,” said Schmid in the release.

“If you do need to take your pet to the emergency hospital, we can develop treatment options on your way in. In many poisoning cases, time is critical, and most veterinarians value the additional toxicology expertise,” she added.

Forget cool cats—dogs are the real potheads. News release. Pet Poison Helpline. December 13, 2023. Accessed December 13, 2023. 

https://www.petpoisonhelpline.com/media-releases/forget-cool-cats-dogs-are-the-real-potheads/

Marijuana. Pet Poison Helpline. Accessed December 13, 2023. 

https://www.petpoisonhelpline.com/poison/marijuana/

Carprofen. Pet Poison Helpline. Accessed December 13, 2023. https://www.petpoisonhelpline.com/poison/carprofen/

The Pet Poison Helpline compiled lists for dogs and cats as well as all species based on their call data  