Gastrointestinal (GI) motility disturbances are widely underrecognized in dogs and cats, primarily because we do not have good tools to diagnose them. Delayed transit disorders are suspected commonly by clinicians and may involve the esophagus (megaesophagus and dysmotility), stomach (delayed gastric emptying), small intestine (postoperative ileus and pseudo-obstruction), or colon (constipation and megacolon).

This two-part article discusses general causes of GI motility disorders affecting the esophagus to the colon, and offers insight for appropriate diagnostic evaluation and treatment options for these disturbances. This article covers the GI tract as a whole; a second article will focus on esophageal diseases that cause motility disturbances.

Vomiting is the predominant clinical sign in dogs and cats with gastric motility disorders. Gastric mucosal disorders may cause motility disturbances due to hypomotility or pyloric outflow obstruction. The most common causes of outflow obstruction are foreign bodies and/or intraluminal masses (e.g., mucosal and/or muscular proliferative diseases), whereas infiltrative diseases may cause generalized hypomotility. Gastric dilatation and volvulus may also cause outflow obstruction but is not further discussed here. Gastric hypomotility and defective propulsion may also be associated with diverse inflammatory conditions and metabolic/systemic diseases, such as chronic gastritis, inflammatory bowel disease (IBD), 

 spp infection, ulceration/erosions, pancreatitis, hypokalemia, hypocalcemia and hypoadrenocorticism.

Gastric retention (i.e., retained gastric contents eight to 10 hours after meal ingestion) has two causes: gastric hypomotility and pyloric outflow obstruction. With pyloric outflow obstruction due to foreign bodies (an especially common cause in young animals;

), an acute onset of vomiting typically occurs. These patients may be painful in the cranial abdomen on physical examination. Therefore, clinicians should take the time to rule in or out a foreign body with a diagnostic workup that includes abdominal imaging (survey radiographs for radiodense objects), with barium contrast if necessary to demonstrate a filling defect if the object cannot be visualized on survey radiographs (

Contrast radiography can be beneficial if ultrasound is unavailable or unrewarding. Gastroscopy serves to confirm the cause of obstruction, and can help with removing the obstructing object and/or sampling mass lesions via exfoliative cytology or forceps biopsy (

). With infiltrative disease (e.g., nonspecific chronic gastritis, IBD), intermittent episodes of vomiting food and bile, hematemesis, melena, abdominal discomfort and weight loss may occur. In patients with chronic gastritis, retained gastric fluids and ingesta noted on gastroscopy may be a clue that a concurrent motility disturbance is present (

Keep in mind that gastric motility disturbances other than mechanical obstruction (e.g., delayed gastric emptying) have diverse causes, including mucosal inflammation (e.g., chronic gastritis, IBD), infection (gastric 

 spp), and dysmotility of unknown cause. Delayed gastric emptying has also been associated with with numerous secondary conditions, including hypokalemia, metabolic disorders (e.g., Addison’s disease, uremia, diabetes mellitus), use of concurrent drugs (e.g., anticholinergics), and acute abdominal inflammation.

Treatment of gastric motility disorders is as follows:

 gastric polyp (polypectomy), tumor (biopsy/gastrectomy +/- chemotherapy), foreign body (endoscopic/surgical removal)

 inflammation/IBD (hydrolyzed diet +/- prednisone), infection (antibiotics), idiopathic (hydrolyzed/ultra-low-fat diet + prokinetic drugs [e.g., cisapride, ranitidine, erythromycin])

Small and large intestinal motility disturbances

As noted earlier, intestinal motility disturbances can be difficult to document due to inadequate diagnostic tools that yield variable results. For example, methods to measure intestinal transit may include barium contrast studies (with or without food), ultrasonography (very operator dependent), and wireless motility capsule. If a structural disorder (e.g., mechanical obstruction) is suspected, it is advisable to start with survey abdominal radiography followed by contrast radiography to rule out specific intestinal diseases.

Ultimately, identifying and treating the underlying disease process is key to clinical remission. Enteroscopy may be useful for removal of proximal duodenal foreign bodies (

). Clinical signs suggestive of small intestinal diarrhea include large stool volume, watery diarrhea, fetid smell, presence of melena and systemic signs (hyporerexia, ravenous appetitie and/or weight loss); whereas normal stool volume, hematochezia, mucoid stools and/or frequent attempts to defecate are most characteristic of large intestinal diarrhea.

Obstruction of the small intestine is a common reason for dysmotility, especially with luminal foreign bodies. While these objects can lodge anywhere along the small or large intestine, many are diagnosed as lodged jejunal foreign bodies. Linear foreign bodies cause obstruction because of their ability to gather/pleat the intestine to cause partial or complete obstruction, and potential perforation, if not resolved. Intussusception in younger dogs and cats (< 1 year of age) can also cause bowel obstruction (

Patients with complete intestinal obstruction often present with acute signs of vomiting, whereas chronic clinical signs (vomiting, diarrhea hyporexia, and/or weight loss) are most consistent with chronic obstructive disorders. Other causes of intestinal dysmotility include dysautonomia, postoperative ileus, viral enteritis, opioid-induced dysmotility, and the rarely occurring idiopathic pseudo-obstruction (i.e., intestinal dilation with no evidence of mechanical obstruction).

Canine parvovirus can cause hypomotility (functional ileus) of the small intestine as a consequence of severe intestinal inflammation/necrosis secondary to viral infection. Because parvovirus is viral in origin, the mainstay of therapy is supportive care. By supplementing nutrition, correcting hydration and providing other supportive measures (e.g., anti-emetic therapy), motility disturbances and clinical remission can be addressed adequately. With infiltrative disease, such as IBD, alimentary lymphoma, and GI histoplasmosis, obtaining mucosal biopsies will generally yield a definitive diagnosis and the need for specific therapy.

Colonic motility disturbances are characterized predominantly by constipation and megacolon. Constipation denotes infrequent or difficult defication with the passage of dry feces. The causes of constipation are numerous and include intra- or extraluminal mechanical obstruction (bones, hair, neoplasia, pelvic fracture), neuromuscular dysfunction (dysautonomia, lumbosacral disease), metabolic/endocrine disease (hypokalemia, hypothyroidism), and medications (opioids, anticholinergics). Megacolon is characterized by excessive colonic dilation thought to be associated with functional disurbances in colonic smooth muscle. 

Treatment strategies for colonic dysmotility are aimed at removal of the underlying cause; adding dietary fiber; using enemas, stools softeners, or manual extraction of hard feces; and administering promotility drugs (ciasapride, erythromycin, misoprostil). When mass lesions present in the colon are causing partial obstruction, the main differentials are adenocarcinoma and inflammatory polyp, both of which usually can be removed (surgically or via endoscopy) without further complications.

Medical therapy for GI motility disturbances

The primary drug choices for GI motility disorders include agents that stimulate intestinal smooth muscle. These include metoclopramide, cisapride, erythromycin, ranitidine, and misoprostol, each of which has a different mechanism of action. For gastroesophageal reflux and gastric hypomotility, metoclopramide (a dopamine antagonist) and cisapride (a serotonin 5-HT [hydroxytryptamine] agonist) are the primary therapeutic choices because they promote gastric emptying and increase lower esophageal sphinter tone to prevent reflux. Metoclopramide will have limited effect distal to the pylorus but will likely facilitate gastric contractions and movement of fluid/ingesta through the pylorus. Because cisapride affects the smooth muscle of the entire GI tract, it may be beneficial in treating different causes of GI hypomotility involving the stomach and intestines.

For small intestinal dysmotility, cisapride, ranitidine and erythromycin are good treatment options. Ranitidine is a histamine 2 antagonist but has prokinetic activity, especially when treating small intestinal hypomotility. Erythromycin works via motilin-like activity and has prokinetic activity at sub-antimicrobial doses; it is also useful for stimulating smooth muscle of the small intestine. Occasionally, dogs with small intestinal IBD that are experiencing continued diarrhea despite diet and immunosuppressive therapy will respond to a promotility drug, suggesting that infiltrative diseases are associated with dysmotility. A suggested trial period of four to six weeks is recommended in these cases.

For colonic dysmotility/constipation, cisapride is recommended as a first choice agent. Unfortunately, there are few effective promotility medication options for stimulating colonic motility. Pilot study data suggest that misoprostil following meal ingestion may stimulate colonic motility in dogs.

Dr. Jergens is an internist and holds the Donn E. and Beth M. Bacon Professorship in Small Animal Medicine and Surgery, and serves as associate chair for research and graduate studies in the Department of Veterinary Clinical Sciences at Iowa State University College of Veterinary Medicine.

1. Fioramonti J, Frexinos J, Bueno L. Oral prostaglandin E analogues induce intestinal migrating motor complexes after a meal in dogs: Evidence for a central mechanism. 

Articles

Gastrointestinal motility disorders are a diagnostic and therapeutic challenge for many practitioners. Here’s how to narrow down the affected area so you can identify the cause and provide appropriate treatment.

Diagnosis and management of GI motility disorders

Researchers from the University of Liverpool in the United Kingdom are working toward the development of a heartworm vaccine to combat the growing threat posed by the resistance of 

 (AHS) estimates that more than a million dogs in the U.S. have heartworm disease. And according to an 

 in 2018, infection incidence is on the rise, with AHS reporting a 21.7% increase in average cases per clinic between 2013 and 2016. The analysis lists poor compliance with heartworm prevention guidelines (about two-thirds of dogs don’t receive any heartworm prevention) and emerging resistance to macrocyclic lactones as potential causes for the concerning upward trend.

In pursuit of sustainable heartworm prevention, 

, PhD, the study’s principal investigator, and his team first looked at other filarial parasites similar to 

— and were able to identify two common proteins in both parasite species that interfere with the host’s immune system, making them potential vaccine targets. One of the proteins blocks a pathway alerting the immune system to the parasites’ presence, and the other stops T cells from attacking the worms.

For the current study, which is backed by both AHS and the 

, Dr. Makepeace says they will incubate proteins from 

 that are equivalent to the ones identified above with white blood cells from healthy donor dogs to determine their effect on the immune response and to see if any of their immunosuppressive effects can be blocked. “This is an essential step before a clinical trial for a vaccine can be performed,” he adds.

An addition to your heartworm prevention toolbox

But even if Dr. Makepeace and his team reach their goal of a heartworm vaccine (a goal that’s suffered serious delays due to the coronavirus pandemic), they don’t see their work as completely cancelling out the need for preventive drugs and mosquito repellents. “It’s more about extending the life of the tools we have so we don’t reach the nightmare scenario of heartworm being unpreventable,” he explains.

With heartworm infections on the rise, researchers from the University of Liverpool have identified two immunosuppressive proteins in Dirofilaria immitis as potential targets for a novel vaccine.

New study lays groundwork for heartworm vaccine development

, another infectious but rare disease has reared its ugly head—bubonic plague. A squirrel in Jefferson County, Colorado (just west of Denver) tested positive for the disease on Saturday, the first case of plague in the county since 2017, according to a statement released by 

. The squirrel was tested after a citizen reported seeing more than a dozen dead squirrels in the area, according to the statement.

, bubonic plague (the most common form of the disease) can be contracted by humans and household animals if proper precautions are not taken. The disease is infamous for killing about 25 million people in Europe during the Middle Ages. Worldwide, most cases occur in Asia and Africa. According to the 

Centers for Disease Control and Prevention

, an average of seven cases of plague occur in humans each year. No statistics are available for the prevalence of plague in pets.

Cats are more susceptible to plague, and can die if not treated promptly with antibiotics, says JCPH. Cats can contract the illness from flea bites, a rodent scratch/bite, or rodent ingestion. Dogs are not as susceptible as cats but can contract the disease from plague-infected rodent fleas. Humans can be infected through flea bites, the cough of an infected animal, or by coming in direct contact with blood or tissue from an infected animal.

Dogs appear to be more resistant than cats to plague. 

 may include fever, lethargy, inflammation of the lymph nodes below the lower jaw, a pus-like lesion along the jaw, lesions in the mouth, and cough. Symptoms in people are similar to those in cats and include sudden onset of high fever, chills, headache, nausea and extreme pain and swelling of lymph nodes, occurring within two to seven days after exposure. Pet owners should contact their physician or veterinarian immediately if they or their pets display any signs of illness.

JCPH reassures the public that the risk of contracting the bubonic plague is extremely low, but appropriate precautions should be taken:

Eliminate all sources of food, shelter and access for wild animals around the home.

Maintain a litter-free yard to reduce wild animal habitats.

Avoid contact with sick or dead wild animals and rodents.

Use precaution when handling sick pets and have sick pets examined by a veterinarian.

Consult with your veterinarian about flea and tick control for your pets, especially if you live near wild animal populations, such as prairie dog colonies or other known wildlife habitats.

Keep pets from roaming freely outside the home where they may prey on wild animals and potentially bring the disease home.

According to the CDC, antibiotics are effective in treating plague. Without prompt treatment, however, the disease can cause serious illness or death.

The risk for contracting this infectious disease, which in the United States occurs primarily in the West, is extremely low when precautions are taken. 

Colorado squirrel tests positive for bubonic plague

Studies in human medicine have demonstrated that first impressions pave the way for the doctor-patient relationship, and that a physician’s clothing is a component of these important first impressions.

 Specifically, physician attire has been found to affect patients’ trust, confidence, and comfort with their doctors. The research overwhelmingly connects the white laboratory coat with the parameters of trust and confidence.

While patients’ perceptions of physician (and psychiatrist, specifically), nurse, and dentist wardrobe have been well studied, research focusing on clients’ attitudes toward veterinarians’ attire is only in its infancy.

 investigating companion animal owners’ perceptions of, and preferences for, different types of veterinary attire, 449 pet owners were asked for their reactions to photographs depicting eight types of attire for male and female (model) veterinarians:

Formal attire (white dress shirt/black skirt [female], white dress shirt/black pants/necktie [male])

A single facial expression was used for each model veterinarian. Each participant received one of two randomly assigned online surveys associated with either the male or the female veterinarian. They were asked to assess the veterinarian's attire in the context of routine veterinary visits.

In the first part of the questionnaire, the eight photos were displayed randomly and participants were asked, anonymously, to rate their trust, confidence, and comfort in the model veterinarian being shown based on a 7-point scale anchored at “1” (low trust, confidence, and comfort) and “7” (high trust, confidence, and comfort).

Next, participants were shown all eight photos as a set and directed to rank them according to personal preference for each style of dress. Subjects were also asked to respond to statements regarding the overall importance of veterinary attire, their preference for name tags for veterinarians, and their ratings for specific items of appearance/attire (visible tattoos, running shoes, sleeveless tops, ear and facial piercings (male/female), long hair worn down, facial hair (male), necktie (male), and skirt (female).

The last part of the survey requested demographic data (respondent gender, age, education level, annual household income) and inquired about the respondent’s pet and veterinarian (i.e., number of years affiliated with current veterinarian, frequency of veterinary visits, type of attire worn by their veterinarian).

The study, performed by researchers at the University of Guelph in 2015 and published earlier this year in the 

Journal of the American Veterinary Medical Association

, recruited adult participants in person at various dog parks in southern Ontario as well as via snowball sampling methods through social media.

Statistical analyses of the data controlled for independent variables such as gender of participant and of randomly assigned model, participant demographics and recruitment method, and gender/usual attire of participant’s regular veterinarian.

Most (71%) of the study participants — who were overwhelmingly female and college-plus educated, and take their pet to the veterinarian a mean of 2.4 times a year — expressed that a veterinarian’s attire is important. When asked to rank their preference among the eight wardrobe styles, their top choice for male and female veterinarians was surgical scrubs. Least preferred was formal attire.

For trust, confidence, and comfort scores, surgical scrubs garnered the highest ratings. For trust and confidence, high scores were also given to model veterinarians clad in a white laboratory coat and khakis. Trust and confidence were lowest for model veterinarians wearing casual shirt and jeans; comfort scores were lowest for model veterinarians dressed in formal attire.

Along with attire, the gender of the model veterinarian and the education level of the participant also impacted trust in and comfort with the model veterinarian.

Among individual items of attire, running shoes were most frequently (64%) rated as appropriate, while sleeveless tops were most often (58%) rated as inappropriate. Well over half of the participants (66%) conveyed the belief that veterinarians should wear a name tag while interacting with clients and their pets.

While this study demonstrates that a veterinarian’s work garb functions as an unspoken message to pet owners, there is variation in clients’ views on clothing selection. Studies in human medicine revealed that preferences in physician attire vary with severity of illness, time of day,

General practice guidelines for staff attire, the authors concluded, could enable veterinarians to better meet pet owners’ expectations and enhance the doctor-client relationship. Based on high demand expressed in this study, hospital managers might consider including staff name tags in their attire protocol.

Dr. Capuzzi is a small animal veterinarian and journalist based in the Philadelphia area.

1. Gherardi G, Cameron J, West A, et al. Are we dressed to impress? A descriptive survey assessing patients’ preference of doctors’ attire in the hospital setting. 

2. Aldrees T, Alsuhaibani R, Alqaryan S, et al. Physicians’ attire: parents’ preferences in a tertiary hospital. 

3. Rehman SU, Nietert PJ, Cope DW, et al. What to wear today? Effect of doctor's attire on the trust and confidence of patients. 

4. Sugerman-McGiffin T, Hybki GC, Castro J, et al. Clients’ attitudes toward veterinarians’ attire in the small animal emergency medicine setting. 

5. Robb KA, Rossi TA, Tansey C, et al. Evaluation of owners’ attitudes towards veterinarian attire in the small animal specialty setting in North America. 

6. Coe JB, O'Connor R, Pizzolon CN, et al. Investigation of the effects of veterinarians' attire on ratings of trust, confidence, and comfort in a sample of pet owners in Canada. 

7. Nibhanipudi KV, Mason B, Pandey A, et al. A study regarding Spanish-speaking parents’ preference of physician attire in the pediatric emergency room. 

8. Li SF, Haber M. Patient attitudes toward emergency physician attire. 

A maiden study pinpoints wardrobe styles pet owners prefer from their veterinarian, uncovering links between attire and the levels of trust, confidence, and comfort clients associate with the doctor. 


Study shows clients care what veterinarians wear

The J. M. Smucker Company has voluntarily recalled one lot of

 Ultra Premium Chicken & Liver Paté Formula canned cat food due to health concerns associated with elevated levels of choline chloride, according to the 

. This wet food is sold in pet specialty retailers and online throughout the U.S. and Canada.

The company says that ingestion of the product may cause nausea with excessive salivation, constricted pupils and poor vision, diarrhea or vomiting, difficulty walking, muscle shaking, tremors, irregular heartbeat, difficulty breathing, possible cardiac or respiratory failure and, in extreme situations, death.

Pet owners are encouraged to contact their veterinarian immediately if their cat has eaten this food and displays any of these signs.

Below is a full description (found on the bottom of each can) of the affected product. No other Natural Balance products are impacted by this recall.

Natural Balance Ultra Premium Chicken & Liver Paté Formula canned cat food 5.5 oz can

Pet owners who have this product in their possession should discard it immediately. Anyone with questions is advised to call the company at 888-569-6767.

J. M. Smucker has recalled one lot of a cat food brand because of potential health concerns associated with high levels of this organic compound.

Cat food recalled due to elevated levels of choline chloride

Just a few short months ago, I was looking forward to a vacation in Puerto Rico and wondering how the Michigan Spartans would fare in the March Madness NCAA basketball tournament. But the harsh reality of a pandemic would soon put a huge dent in all my plans.

At the start of the COVID-19 crisis, I reassured my clients that our team would be available for them and their pets, but pet owners were flocking to the practice in such large numbers that we had to put strict measures in place to help prevent the spread of this deadly virus.

Handshakes were replaced with elbow bumps, and doorknobs, phones, and other surfaces were disinfected every 15 minutes. We also cut down on appointments to reduce the number of clients in the lobby and eventually started curbside service.

All staff members wore PPE throughout the day, and our team was split to two in order to comply with social distancing recommendations. We also delayed routine appointments and surgeries, and prioritized essential services.

Although the experience made my head spin on more than one occasion, for me there is a silver lining in this pandemic: gratitude. I appreciate being in a profession that is deemed essential, and I’ve been so grateful to observe how much our patients are loved and the important place they have in their families’ hearts.

Although Michigan was one of the first states to issue mandatory stay-at-home orders, I have overall been impressed with how clients are catering to their pet’s wellbeing throughout all of this. Whether they are seeking help for their pets via telemedicine or risking their own health to drop off their pet curbside, I’ve noticed that the human-animal bond has strengthened during these tough times.

I’ve also been fascinated by how committed people are in this field. The high quality of care, compassion, and positive attitude that our kennel staff, receptionists, technicians, and doctors have displayed time and time again have been exceptional. With clients unable to enter the building, another upside is that we’ve had more vulnerable and fun moments together as a team.

Overall, these challenging and unprecedented times have taught me that while it’s easy to get depressed with all the negativity, gratitude is key. I’m thankful to be in the veterinary profession, to have the clients that I do, and to work with such an amazing team.

Dr. Andrew Rollo is an associate at Madison Veterinary Hospital in Madison Heights, Michigan.

For this veterinarian, the COVID-19 pandemic has reaffirmed his love and appreciation for the veterinary profession.