8 Weird Dog Behaviors Explained: What Vets Really Say About Morning Stiffness, Grass-Eating, and More
Every dog owner accumulates a running list of small, nagging questions between annual checkups: Why does she circle three times before flopping down? Why is he stiff getting off the couch but fine an hour later? Is grass-eating a sign something's wrong, or just a Tuesday? Veterinarians hear these exact questions constantly, and most have concrete, well-studied answers rooted in canine physiology rather than folklore. This roundup tackles a second batch of the questions that come up most in exam rooms, with the actual data behind each one.
At-a-glance guide
| Section | Key takeaway |
|---|---|
| Why is my dog slow to get up in the morning? | Stiffness after rest is the hallmark early sign of osteoarthritis, a condition the American College of… |
| Why does my dog eat grass and then sometimes throw up? | Grass-eating is extremely common and not automatically a sign of illness. |
| Why does my dog circle around and around before lying down? | Circling before bedding down is considered an instinctive, largely harmless behavior rooted in wild canid… |
| Is it normal for my dog's nose to be dry sometimes and wet other times? | Nose moisture fluctuates constantly throughout the day based on ambient humidity, room temperature, sleep… |
| Why does my dog eat poop, and is coprophagia dangerous? | Coprophagia (stool-eating) is reported in a large-scale survey of over 3,000 dogs to occur in roughly 16%… |
| How much sleep does my dog actually need, and is my dog sleeping too much? | Adult dogs typically sleep 12 to 14 hours per day, and puppies and senior dogs can sleep 18 hours or more,… |
| Why is my dog panting heavily at night when it's not hot in the house? | Nighttime panting unrelated to temperature or recent exercise is one of the more commonly under-reported… |
Why is my dog slow to get up in the morning?
Stiffness after rest is the hallmark early sign of osteoarthritis, a condition the American College of Veterinary Surgeons estimates affects roughly 20% of dogs over age one and the majority of dogs over age eight, with large and giant breeds and overweight dogs at the highest risk (American College of Veterinary Surgeons, n.d.). Joint cartilage breaks down gradually, and inflammatory fluid accumulates overnight while the dog is immobile, so the first steps after waking or after a nap are typically the most labored part of the day.
Diagnosis usually starts with a gait and orthopedic exam, and Cornell Riney Canine Health Center notes that radiographs (often under light sedation) are used to confirm joint changes and rule out other causes of lameness such as a torn cruciate ligament (Cornell Riney Canine Health Center, n.d.). Management commonly combines an omega-3 fatty acid or glucosamine/chondroitin supplement, a veterinary nonsteroidal anti-inflammatory, weight control, and low-impact exercise like leash walking or swimming rather than rest alone, since muscle loss around an arthritic joint tends to make the stiffness worse over time.
Quick decision guide
Why does my dog eat grass and then sometimes throw up?
Grass-eating is extremely common and not automatically a sign of illness. A frequently cited survey of dog owners found that roughly 68% of dogs had eaten plants at some point and that vomiting was reported after grass consumption only about 22% of the time, suggesting most dogs graze without it representing a coping mechanism for nausea (American Kennel Club Canine Health Foundation, n.d.). Some researchers view it as a normal ingestive behavior possibly tied to fiber intake or simple foraging instinct rather than illness.
That said, sudden, obsessive, or frantic grass-eating paired with lethargy, repeated vomiting, or a distended abdomen warrants a same-day vet visit, since these signs overlap with gastrointestinal obstruction or pancreatitis. The AVMA recommends keeping lawns free of pesticides and herbicides if a dog grazes regularly, since ingestion of treated grass is a distinct and preventable toxic exposure separate from the grass-eating behavior itself (American Veterinary Medical Association, n.d.).
Why does my dog circle around and around before lying down?
Circling before bedding down is considered an instinctive, largely harmless behavior rooted in wild canid ancestry, where flattening grass or checking for hidden hazards and temperature before settling had survival value; most veterinary behaviorists classify it as normal unless it becomes prolonged, repetitive to the point of distress, or paired with other compulsive signs (Merck Veterinary Manual, 2024). A dog that circles once or twice and settles quickly is behaving typically.
Circling that escalates, occurs dozens of times before the dog can settle, or is accompanied by pacing, whining, or apparent disorientation can point toward orthopedic pain that makes finding a comfortable position difficult, or in senior dogs, canine cognitive dysfunction. Cornell Riney Canine Health Center notes that new-onset repetitive circling in a dog over age ten should prompt a veterinary evaluation for cognitive decline, which affects an estimated 14 to 35% of dogs over age eight to a measurable degree (Cornell Riney Canine Health Center, n.d.).
Is it normal for my dog's nose to be dry sometimes and wet other times?
Nose moisture fluctuates constantly throughout the day based on ambient humidity, room temperature, sleep state, and how recently the dog last licked its nose, and the AVMA lists nose texture as an unreliable standalone indicator of health in either direction (American Veterinary Medical Association, n.d.). A dog can have a bone-dry nose after a nap and a wet one twenty minutes later with no change in health status.
What matters more than moisture is whether the nose develops cracking, crusting, thickened texture, discharge, bleeding, or depigmentation, since those changes can signal conditions like nasal hyperkeratosis, autoimmune skin disease, or in rare cases nasal tumors. Merck Veterinary Manual advises owners to photograph and monitor any nasal texture change that persists beyond a week rather than relying on wet-versus-dry as a health check (Merck Veterinary Manual, 2024).
Which of these everyday dog behaviors should send you to the vet right away?
Most of the behaviors above are variations of normal, but certain combinations cross into emergency territory. Seek immediate veterinary care for a distended or bloated abdomen with unproductive retching (possible gastric dilatation-volvulus), collapse, pale or blue gums, labored breathing at rest, sudden inability to rise or use the hind legs, or repeated vomiting combined with lethargy and grass-eating, since these can indicate obstruction, bloat, or acute pain rather than a benign quirk (American Veterinary Medical Association, n.d.).
For the specific behaviors covered here, escalate quickly if morning stiffness progresses to a dog that won't bear weight at all, if grass-eating becomes frantic and paired with a hard or swollen belly, if circling becomes constant and the dog seems unable to settle or appears disoriented, or if nighttime panting is joined by gum color changes or open-mouth breathing while resting. Any of these deserves a same-day call to your veterinarian rather than waiting for the next routine appointment.
Bottom line
Most of these everyday dog quirks—morning stiffness, grass-eating, circling before bed, a dry nose, stool-eating, heavy nighttime panting—have identifiable, usually manageable explanations, and a vet visit with a physical exam plus basic bloodwork sorts out the rare cases that need real treatment. Track when a behavior started and how often it happens, because that pattern is often more diagnostically useful than the behavior itself.
Why does my dog eat poop, and is coprophagia dangerous?
Coprophagia (stool-eating) is reported in a large-scale survey of over 3,000 dogs to occur in roughly 16% of dogs on a regular basis, with terriers and hounds overrepresented and the behavior most common in multi-dog households, according to research summarized by the University of California, Davis (UC Davis Veterinary Medicine, n.d.). Most cases in otherwise healthy dogs are behavioral rather than nutritional, and the same study found no strong link to a specific dietary deficiency, which contradicts a common owner assumption.
Veterinarians still recommend ruling out exocrine pancreatic insufficiency, malabsorption, or intestinal parasites with a fecal exam, particularly if the behavior starts suddenly in an adult dog, since some medical causes of increased appetite or malabsorption can present this way. Management typically focuses on prompt yard cleanup, supervised outdoor time, and taste-deterrent products rather than diet changes alone.
How much sleep does my dog actually need, and is my dog sleeping too much?
Adult dogs typically sleep 12 to 14 hours per day, and puppies and senior dogs can sleep 18 hours or more, according to guidance from the American Kennel Club, with breed size, activity level, and age all shifting that baseline (American Kennel Club Canine Health Foundation, n.d.). A dog that naps through most of a quiet afternoon at home is behaving typically rather than showing a red flag.
A meaningful increase in daytime sleep paired with reduced interest in walks, food, or play is a different signal, and can point toward hypothyroidism, anemia, pain, or depression-like states following a household change such as the loss of a companion animal. Tracking the change against a known baseline, and bringing that timeline to a veterinary visit along with basic bloodwork, is more useful diagnostically than describing the sleep change alone.
Why is my dog panting heavily at night when it's not hot in the house?
Nighttime panting unrelated to temperature or recent exercise is one of the more commonly under-reported signs owners bring up almost as an afterthought, yet it can reflect pain, anxiety, Cushing's disease, heart disease, or early respiratory compromise. The American Animal Hospital Association notes that abnormal panting is a recognized indicator of pain in dogs, particularly when paired with restlessness or an inability to get comfortable (American Animal Hospital Association, n.d.).
A veterinary workup for unexplained panting typically includes a physical exam, chest radiographs, and bloodwork including a chemistry panel to screen for Cushing's disease or early cardiac disease, since brachycephalic breeds and older large-breed dogs carry elevated risk for both. Persistent panting that doesn't resolve with cooling the room or ending exercise for more than a day or two is reasonable grounds for a vet visit rather than a wait-and-see approach.
References
- American College of Veterinary Surgeons. (n.d.). Osteoarthritis in Dogs. https://www.acvs.org/small-animal/osteoarthritis-in-dogs
- Cornell Riney Canine Health Center. (n.d.). Canine Cognitive Dysfunction and Aging. https://www.vet.cornell.edu/departments-centers-and-institutes/riney-canine-health-center
- American Kennel Club Canine Health Foundation. (n.d.). Canine Health Information and Research. https://www.akcchf.org
- American Veterinary Medical Association. (n.d.). Pet Care and Poison Prevention. https://www.avma.org/resources/pet-owners
- Merck Veterinary Manual. (2024). Normal Behavior and Behavioral Problems in Dogs. https://www.merckvetmanual.com/dog-owners
- UC Davis Veterinary Medicine. (n.d.). Coprophagia in Dogs Research. https://www.vetmed.ucdavis.edu
- American Animal Hospital Association. (n.d.). Pain Management Guidelines for Dogs and Cats. https://www.aaha.org/resources/pain-management