"Never use your hands to break up a fight. Use barriers, loud commands, leashes, or objects to separate animals. Human bites from redirected aggression can be life-changing."— Dr. Michael LoSasso, DVM
Episode summary
Bite wounds are the most deceptive injuries in emergency veterinary medicine — a neat pinhole on the surface can conceal torn muscle, crushed tissue, ruptured vessels, and bacteria sealed beneath the skin. In this episode, Dr. LoSasso explains why small punctures are often more dangerous than dramatic lacerations, how dog skin mobility allows a single bite to travel far beneath the surface, and how the veterinary approach to suturing has evolved to avoid closing wounds that are already compromised.
He covers the differences between dog bite and cat bite injuries in detail. Cat bites are narrow and needle-deep, creating the perfect environment for abscesses that can smolder for days before bursting. The location of a cat's wounds often tells the story of the conflict — intact males get face abscesses from head-to-head combat; neutered cats and females get bitten above the tail as they flee.
Dr. LoSasso also discusses North Texas-specific hazards: copperhead snakebites, which are common east of Lake Dallas, and their characteristics (two punctures, rapid swelling, dark oozing blood). He explains how venom dose varies and how the decision to use antivenom is guided by serial examination rather than guessing.
"The dramatic lacerations that look the worst are not always the most dangerous. Quiet punctures often carry the highest risk because they trap bacteria and mask the extent of internal trauma."— Dr. Michael LoSasso, DVM
Never use your hands to break up an animal fight
Redirected bites from a dog mid-fight can cause severe injuries. Use barriers, loud noises, a leash, or an object between the animals to separate them. In many areas, any treated bite — even from a vaccinated pet — triggers mandatory reporting and quarantine procedures.
Questions answered in this episode
The following questions are answered by Dr. LoSasso in this episode, drawn directly from the conversation. These are real clinical answers from a practicing emergency veterinarian with 30+ years of experience.
Dr. LoSasso says the visible skin wound is just the entry point. Dog bites involve tremendous crushing force — canine skin glides over the body, allowing a single fang to travel beneath the surface and tear tissue far from the entry point. He routinely finds intercostal muscle damage, abdominal wall hernias, and lung injury with almost nothing visible on the coat. Size mismatch makes it worse — a large dog grabbing a small dog can cause rib fractures, punctured lungs, and crushing injuries in seconds.
Cat teeth are needle-sharp and inject bacteria deep under the skin, creating a perfect environment for abscesses. The skin seals quickly over the puncture, trapping bacteria. Cat bite abscesses can smolder for days before bursting, leading owners to believe the initial fight was minor. Dr. LoSasso notes that the location reveals the story: intact males get face abscesses from head-to-head fighting; neutered cats and females are bitten above the tail as they flee. Early evaluation, drainage, and targeted antibiotics shorten recovery significantly.
Not necessarily. Dr. LoSasso says the approach to suturing has evolved. Years ago, large lacerations from dog bites were often closed immediately with drains — and too many of those closures failed because the skin's blood supply was already compromised. Devitalized tissue turns dark and dies. For severe soft-tissue injuries, he now often delays closure for two to three days to allow the true borders of viable tissue to declare themselves. Rushing into suturing can produce a worse outcome than waiting.
Dr. LoSasso says copperheads are common east of Lake Dallas and their bites typically show two punctures less than an inch apart, rapid swelling, and dark oozing blood. Antivenom is the most effective treatment when envenomation is clear. Venom dose varies with the snake's age, recent meals, and whether the strike was defensive — dry bites may not require antivenom, but guessing wrong wastes precious time. Veterinary assessment and serial exams guide the decision. Get to an emergency vet immediately.
Rabies is rare in vaccinated household dogs in the United States, but the law takes bites seriously. When wildlife or stray exposure is possible, vaccination status, revaccination, and mandated observation protocols protect both people and pets. Many areas require mandatory reporting and observation periods even when the biting animal is vaccinated. Owners rarely have the biting animal for testing, so prevention — keeping vaccinations current and avoiding wildlife contact — is the most important protection.
JulieWhat are some of the most common animal bites you've treated?
Dr. LoSassoThe most common are among housemates — dogs biting other dogs. We see cats biting other cats, usually free-roaming outdoor cats interacting with an intact male in his territory, and we typically deal with that after the fact once an abscess has formed. Cat mouths are nasty and those teeth are like needles — you never want bacteria injected under your skin. The only wildlife bites we see with any regularity are snake bites, which are getting ready to start up as the season begins.
JulieWhat should a pet owner do immediately if their animal is bitten?
Dr. LoSassoFirst: don't break up a dog fight with your body — especially not your hands. Use a broomstick, yell, pull on a leash. With redirected aggression, even dogs that wouldn't normally bite you are in the heat of battle, and bites in that moment are serious. In the state of Texas, any animal bite treated by a physician must be reported to the Department of Health, which triggers rabies quarantine. Even vaccinated dogs have to be quarantined. The challenge with dog bites is that dog skin is really, really mobile. You can scrunch it up a lot. What that means is that a bite will leave a puncture wound on the surface, but because the skin moved around the whole time that tooth was in it, there is a tremendous amount of damage underneath — muscles between ribs ripped apart, abdominal wall hernias where the only thing holding the intestines in is skin.
Dr. LoSassoI've had part of one of my ears removed by a dog. But I was actually closer to a serious hospitalization after being bitten by a cat, because of the bacteria in their mouths. People think dog bites are the serious ones, but cat bites can be worse. For a long time we tried to close large lacerations from dog bites immediately. Too many of those closures failed because the blood vessels to that skin were torn — the skin loses its blood supply, turns black, and dies. We now often treat severe soft tissue disruption as open wounds for two to three days before even considering closure.
Dr. LoSassoThe bloody ones that look worst are often ear bites — a tiny V-notch cut out of the ear tip. Ears bleed, dogs shake their heads, and people say 'I've got blood on my ceiling.' But the actual blood loss is almost insignificant. We don't worry about that. For cat abscesses: if you've got two intact males fighting, they fight tooth to tooth on the face. A female or neutered male gets bitten right above the tail because they're trying to get out of the territory. Those abscesses can smolder for days before bursting.
Dr. LoSassoCopperhead season is starting in this part of the world. In Frisco, we're on the east side of Lake Dallas, so we see mostly copperheads. They're venomous and can cause real damage, but they're not as scary to treat as the rattlesnakes west of the lake or water moccasins. Snake bites: you can tell because you've got a couple of very small puncture wounds less than an inch apart in the middle of what's now a really swollen area with some dark blood. Venom dose depends on the species, the snake's age, when it last ate, and why it bit. A snake that recently ate probably doesn't have much venom left. Young snakes aren't more venomous — that's a myth — but they have less control over how much venom they release. In a 'terminal bite' where a dog has picked a snake up and is swinging it around, that snake is going to give everything it has. Antivenom is the most effective treatment — it stops the swelling and is actually the best pain medication we can give.
Dr. LoSassoRabies is a very small problem in domesticated dogs in the United States, but it matters. Most people don't realize 60,000 people a year die of rabies globally — mostly India, Middle East, parts of Africa where comprehensive vaccine programs don't exist. If the biting animal is a stray or wildlife, we can't test it. So we make sure the bitten animal is vaccinated and probably revaccinate to be safe.