Consider these pros and cons before attaching a bell to your cat’s collar.
Does your cat bring you dead animals? While this common behaviour is kind of yucky, it’s also sort of endearing – your cat is bringing you what she believes to be an excellent gift. But despite their generous intentions, hunting by domestic cats is affecting ecosystems and pushing some species to extinction. So what can you do to keep your cat from catching wildlife? There are two primary solutions to consider: keep her inside, or attach a deterrent (such as a bell) to her collar.
A closer look at the options
Of course, the easiest method of preventing your cat from killing birds and rodents is to keep her inside all the time. In the safety of your home, your feline’s exposure to prey animals will be limited to any mice that happen to get into your house. If you aren’t willing to curb your feline’s wanderlust, a common alternative is to attach a bell to her collar to alert wildlife of her approach. But is this a safe and effective option?
The pros and cons of bells
A number of studies have looked at whether or not bells help prey escape from cats, and the general consensus is yes! Bells on collars seem to reduce the amount of prey caught by about half, which could be enough to no longer pose a threat to ecosystems.
Effectiveness aside, many pet parents worry that a bell will hurt their cat’s ears. According to Veterinary PhD student Rachel Malakani, a collar bell will produce sound at about 50-60 dB, but studies have shown cats to be unaffected by sounds under 80 dB. While some cats with anxiety may not react well to the bell’s sound, it’s likely that the majority of cats simply won’t care.
Some owners worry that as well as alerting prey, a bell would also alert large predators to a cat’s presence. While this is possible, given most predator’s acute hearing, it’s unlikely that the relatively quiet noise of a bell would make the difference between your cat getting detected or not. If you live in an area where your cat is at risk of being attacked by large animals you should probably be keeping your cat indoors anyway, or at least supervise their outdoor activities. You can also invest in a cat enclosure, which will allow your feline to enjoy the fresh air safely!
If you’re unwilling to put a bell on your furry buddy, you do have another option – cat bibs. Sold under names like Birdsbesafe, these devices are brightly colored to alert potential prey to the cat’s presence before they can pounce. While your cat might look a bit silly wearing a rainbow bib, the scientific research on these products shows they reduce predation rates by roughly the same amount as bells. That said, the devices that rely on color to alert potential prey work much better on birds (who have very good color vision) than they do on small mammals (who generally have quite poor vision).
If you’re scared of attaching any collars or collar-mounted devices to your felines – you shouldn’t be. While fears that cats can become strangled or trapped by a collar caught on debris are common, actual adverse effects from collars are rare. One study looked at 107 veterinarian practices and found only one collar-related injury per every 2.3 years, with collar-related deaths being even rarer. You can mitigate your fears further by using a breakaway collar.
If your cat ventures outdoors, especially if you live in an area with endangered species, please do your part to aid conservation efforts by outfitting your kitty with an anti-hunting device.
If you ask a dog owner what dogs cannot eat, they’ll list some foods like onions, garlic, rhubarb, grapes and chocolate. (As an aside, if they say grains, don’t listen to them.) Dogs’ inability to safely consume chocolate is common knowledge, but thanks to their proclivity for eating anything they can get their mouths on, many dogs are nonetheless treated for ingesting chocolate every year.
However, there are also many, many dogs who eat chocolate (with or without their owner’s knowledge) who are perfectly fine, no treatment necessary. If chocolate is so bad for dogs, why are these candy-consuming canines fine?
Because, as with all things, the dose makes the poison.
The components of chocolate that are toxic to dogs are theobromine and caffeine. These two chemicals are, structurally, almost identical, and both belong to a group of chemicals called methylxanthines.
Part of what makes methylxanthines so dangerous to animals is how slowly they process them, in particular, theobromine. While dogs reach peak serum (the non-cell part of blood) levels of caffeine after 30-60 minutes and eliminate half of an ingested dose in 4.5 hours, they don’t reach peak serum levels of theobromine until after 10 hours and take 17.5 hours to eliminate half of it.
While they’re in the blood, methylxanthines have a few effects. Primarily, they inhibit the activation of adenosine receptors. These receptors are generally responsible for making us feel sleepy, and decreasing the activity of our bodies. Methylxanthines inhibit these sleepy feelings and act as stimulants.
An aside: Grapefruit’s effects on theobromine metabolism
The enzyme responsible for metabolizing theobromine is a member of the cytochrome P450 family. If you’ve heard of these enzymes its likely because you take a medication that is similarly affected by them (such as Viagra, Cialis, Erythromycin, Xanax and many others) and you’ve been warned to stay away from grapefruit juice. This is due to compounds in grapefruit interfering with the P450 enzymes. Without properly functioning enzymes, medications aren’t broken down as they should be, and overdoses can occur. These compounds aren’t exclusive to grapefruits: they’re also found in pomelos, bitter oranges and Seville oranges that are used to make marmalade. Luckily dogs don’t often consume the fruits that harbour these compounds, however, if Marmaduke ever eats a jar of marmalade as well as some chocolate, he would be in serious trouble.
So, what does this mean for your dog who ate a chocolate bar? It means they will feel nauseous and probably vomit, they’ll have a high heart rate, diarrhea, show signs of hyperactivity and, if they consumed a high dose of methylxanthines, tremors, seizures and possibly death.
What exactly is a high dose of methylxanthines however depends on your dog.
According to the ASPCA mild effects of theobromine poisoning can be seen at a dose of 20 mg/kg. Severe signs begin at about 40 mg/kg and seizures can begin at 60 mg/kg. A median lethal dose (LD50) is the dose of a toxin required to kill half of a sample population. It’s a common way of measuring a lethal dose of a substance in toxicological research, and for theobromine, the LD50is 100-200 mg/kg.
Notice that because all of these doses are given per kilogram of dog, what’s a low dose of theobromine for a German Shepard could be an exceptionally large dose for a chihuahua.
To illustrate my point, allow me to introduce three dogs. First, we have Baci, a 5-year-old, 7-kg Maltipoo. She’s considered a small dog by all reasonable metrics.
Next meet Chanelle, a 10-year-old Golden Retriever who is solidly medium-sized at 25 kg.
Last, we have Jupiter, a 5-year-old Malamute/German Shepherd cross who is quite large at 50 kg.
I’ve run some numbers to see how each of these dogs would fair if they ate the same amounts of chocolate. You can see my results in the chart below and can replicate my calculations easily using one of the online chocolate toxicity calculators.
(Green = <20 mg/kg, yellow = 20-40 mg/kg, red = 40-60 mg/kg, black = >60 mg/kg)
So, we can see that while Jupiter will probably be fine if he scarfs down 1/3 cup of cocoa powder (the amount in your average recipe for brownies), Chanelle would likely be sick, and Baci would be facing seizures and possibly death.
It’s easy to see, when you start playing with the numbers, how so many dogs can eat chocolate-containing foods and be totally fine. Chanelle could easily consume ½ cup of chocolate ice cream, or a chocolate pudding cup, or a chocolate cupcake and not even show the slightest sign of being sick!
An aside: What about mulch made from cocoa bean shells?
In recent years cocoa-bean-based mulch has gained popularity as an attractive alternative to traditional mulch. It can be good for your garden, contributing nutrients and preventing weed growth, but it can be really bad for your dog. With up to 32 mg of theobromine per gram, cocoa bean mulch can be a more potent source of theobromine than even pure unsweetened baking chocolate. If you can’t guarantee that a dog won’t munch on your mulch, you’re better off sticking to the traditional mulches, which come with the bonus of being much cheaper!
Even if your dog doesn’t get sick from eating small amounts of chocolate however, it’s still best that they avoid it. One study found that repeated theobromine exposure led to the development of cardiomyopathy (a chronic disease of the heart muscle that makes it harder for the heart to pump blood) in dogs.
An aside: There may also be a genetic component to dogs’ ability to metabolize theobromine
Dogs with a particular variant in their CYP1A2 gene (the variant is 1117C>T) lack the ability to properly metabolize and break down some substances, including lidocaine, naproxen and theobromine. This has important implications in their veterinary treatment and could explain why some dogs get sick after eating very little chocolate.
So, what should you do if you suspect your dog has eaten chocolate? You have a few options. You can check an online calculator (like this one) to see if your dog is likely to exhibit symptoms, or call animal poison control (1-888-426-4435 in Canada and the U.S.). Keeping in mind that such resources are not substitutes for veterinarian care, you should monitor your dog closely no matter what they say, looking for symptoms like a fast heart rate, vomiting or tremors.
If your dog ate an unknown amount of chocolate; is exhibiting symptoms; is pregnant (theobromine can cross the placenta and affect the puppy); or has other health complications, you should take them to a vet right away. Symptoms may not develop until up to two hours after ingestion, but veterinarian anti-chocolate treatments are most effective if performed as soon as possible after ingestion.
And what exactly do they do to cure a dog of theobromine poisoning? Gastric decontamination. The first step is to empty the stomach (if the ingestion was recent enough). This is often done with a drug called apomorphine which is administered through the eye so that it is quickly absorbed.
Next a vet will administer activated charcoal, a finely powdered material capable of binding a variety of drugs and chemicals. Activated charcoal is most effective if given immediately after ingestion of the toxin and is usually given by mixing it with wet dog food (beware: it will turn your dog’s poop black). In some cases, repeat administrations of charcoal are necessary, but in others just one dose will do it.
Beyond these steps, a theobromine-poisoned dog will just be given medicines to manage their specific symptoms, such as Diazepam for seizures or hyperexcitability, beta blockers for high heart rate, Atropine for low heart rate or others.
Before you go: a note on cats
As it turns out, cats are actually more susceptible to theobromine poisoning than dogs, but we don’t ever hear about a cat getting sick from eating chocolate. Why is that?
Mainly because cats don’t eat as indiscriminately as dogs. Dogs are known for eating just about anything they can find (including joint butts, a practice that places them at risk for cannabis poisoning), whereas cats tend to be picky eaters. In part this is explained by the fact that cats lack the ability to taste glucose.
If all chocolate tasted like 100% dark chocolate, you likely wouldn’t eat much of it either.
Take-home message: • Chocolate is poisonous to dogs mostly because of its theobromine content, which dogs are unable to metabolize effectively. •The amount of chocolate a dog can eat without showing symptoms varies drastically with their weight • If your dog eats chocolate, you should monitor them closely and seek veterinary attention if they show any symptoms, or if they are very young, pregnant or have other health concerns.
Special thanks to Rachel Malkani MSc. CDBC and veterinary PhD candidate, and to Henry for inspiring this article by, as you may guess, eating chocolate.
In 1975 police took fingerprints from six chimpanzees and two orangutans housed at zoos in England. They weren’t just looking for a unique souvenir; they were testing to see if any unsolved crimes could be the fault of these banana-eating miscreants.
While these primates ended up being as innocent as they seemed, the police did determine that their fingerprints were indistinguishable from a human’s without careful inspection.
A few years later, in 1996, a different type of mammal came under police suspicions: a koala!
While it makes sense that orangutans and chimpanzees would have fingerprints like us, being some of our closest relatives, koalas are evolutionarily distant from humans. It turns out that fingerprints are an excellent example of convergent evolution, or different species developing similar traits independently from each other.
Another example of convergent evolution is seen in the bony structure supporting both birds’ and bats’ wings.
Fingerprints are thought to serve two purposes. First, they aid in grip, allowing an animal to better hold onto rough surfaces like branches and tree trunks. Second, they increase the sensitivity of our touch and allow us a finer level of perception regarding the textures and shapes of the things we hold.
Why this is useful for humans is obvious. Our hands are made to grasp, hold and manipulate objects. Whether it’s some nuts we foraged for or our Xbox controller, we humans spend all day every day relying on our sensitive sense of touch.
For koalas, it’s not really so different. They are incredibly picky eaters, showing strong preferences for eucalyptus leaves of a certain age. It seems that their fingerprints allow them to thoroughly inspect their food before they chow down.
Police aren’t exactly worried about koala bank robbers, but it is possible that koala fingerprints could be found incidentally at a crime scene and be mistaken for a human’s, making it pretty difficult to find a match.
To read about how fingerprints form, how parts of them are genetic, and why identical twins have different ones, click here!
Take-home message: – THC is very dangerous to most companion animals – Medical cannabis has only a few uses in humans, and even fewer in animals – Cannabis, hemp or CBD treats, food or supplements are not approved or regulated by Health Canada. They are illegal and could be quite dangerous for your pets.
While medical marijuana has been available to varying degrees for decades, with recreational marijuana legalized this week in Canada, discussions about what (if anything) cannabis can treat seem to be at an all-time high (see what I did there?)
Discussions of treating medical problems with cannabis are not limited to humans. If cannabis may benefit humans, it may similarity benefit companion animals like dogs or cats. Considering that some of the major ailments cannabis is touted to treat are prime concerns for pet owners (anxiety, arthritis, pain) it makes sense for pet owners to be curious about cannabis.
Cannabis can be very dangerous for pets
When discussing cannabis and companion animals, it’s important to define a few terms.
Tetrahydrocannabinol or THC is the main psychoactive component of cannabis. As most pet owners aren’t interested in getting their furry friends high, the vast majority of pet-marketed cannabis products are free, or almost free, from THC. Which is good, because THC is quite dangerous for animals.
Since it’s difficult to study cannabis (due to it’s soon-to-expire illegal nature) we lack recent numbers on the dose based effects of THC in dogs. Early studies report intoxication effects in dogs with doses between0.25 and 0.5 mg/kg of body weight. If your average German Shepard is about 30 kg, they would show THC’s effects after ingesting 7.5 – 15 mg, or about a 10th of your average “special” brownie.
Though cannabis intoxication and adverse effects have been reported in other animals like cats, horses and ferrets, it’s much more common in dogs. Why? Because dogs like to eat. As Dr Sarah Silcox, the President of the Canadian Association of Veterinary Cannabinoid Medicine explained to me, “edibles, in particular, are very attractive to dogs, and if left within reach of pets, will often be gobbled up quickly.”
While it’s not likely that pets will die from cannabis exposure (through smoke or edibles) there can still be serious effects, especially if left untreated. Fluffy and Rover probably won’t get a kick out of the intoxicating effects of cannabis, given that they can’t understand what’s happening. Pets may experience significant anxiety, agitation or lethargy. Smoke of any kind can cause respiratory distress and potentially lung cancer to pets who inhale it regularly, due to the polyaromatic hydrocarbons created during incomplete combustion. Cats in particular are at risk of developing malignant lymphomas when exposed to secondhand cigarette smoke, a risk that may transfer to other types of smoke. .
So what’s with all the cannabis products for pets then?
Pet treats, foods and supplements in general feature no THC. They instead contain a different cannabinoid found in cannabis: cannabidiol or CBD. CBD is not toxic to animals like THC, and it does not cause the same psychoactive effects.
This study of 16 dogs with osteoarthritis showed a significant decrease in pain after treatment with CBD oil, but similar studies, or studies looking at cannabis to treat other conditions are seriously lacking.
Dr Silcox mentioned many anecdotes of positive effects of CBD products on pets, and this survey have found that that well over half of all owners polled who have used cannabis products on their pets felt it helped. But anecdotes are never evidence enough. We need good, large, controlled studies to properly evaluate the potential benefits and risks of cannabis products on cats, dogs and other pets.
For pain treatment however, the evidence for cannabis hasn’t looked wonderful. This 2015 review found evidence for use of low dose cannabis for neuropathic pain, but not for other pain. This 2018 Cochrane review states that the use of cannabis for “chronic neuropathic pain might be outweighed by their potential harms.”
Second, as Dr Silcox wrote, there is a “concern that that pet owners will attempt to medicate their pets with cannabis products and without appropriate guidance, put their pets at risk of adverse effects.” When we give our pets, children or ourselves any medication we first check dosage information, but the problem is that it isn’t available in any well researched, accurate or well-defined way for most species.
Third, pet owners may use cannabis in lieu of other evidence-based treatments, putting their pets at risk or hurting their quality of life. We don’t really know what cannabis can or should be used for in animals, but that hasn’t stopped many owners from using it for things like pain, anxiety management and diabetes management. My fear, simply put, is that owners will choose cannabis over NSAIDS, over other pain killers, over insulin, and even over euthanasia. I hope that no animals are suffering as a result of receiving cannabis as an alternative treatment to conventional veterinary medicine, but my fear is that it’s already happening and will begin to happen more with legalization.
Whether they work or not, they’re illegal and unregulated.
Until October 17th, 2018 all products containing plant-derived cannabinoids (which includes THC and CBD) fall under the Controlled Drugs and Substances Act. But even after the 17th, it isn’t open season for cannabis products. The new Cannabis Act will regulate the approval and sales of cannabis products, meaning that anything sold legally will need to be approved by Health Canada.
Health Canada currently has no products approved for veterinary or animal use. So CBD and cannabis products currently have, as Dr Silcox explains, “no regulatory oversight to ensure their quality, safety, or effectiveness. While they are marketed to treat a range of ailments, these health claims are unsubstantiated by Health Canada, the products are not approved, and as such, are not compliant with Canadian law.”
Now, that could soon change. With legalization around the corner, studies on cannabis and its effects are about to become a lot more feasible. With more evidence we will be able to hash out which CBD claims have merit, and which are baseless.
With entire conferences being held on veterinary use of cannabis we can hopefully expect some answers soon. In the meantime, a few things remain really important.
Our bodies and fishes’ (yes, fishes is a grammatically correct plural form of fish) bodies as well need water. Without it, the chemical reactions that take place constantly in our bodies would have no solvent and we would die.
Nonetheless, it seems silly that an underwater creature should have to drink. Can’t they just, I don’t know, absorb it or something?
Fish do absorb water through their skin and gills in a process called osmosis. Osmosis is the flow of water across membranes from areas of low concentration of dissolved things (solutes) to areas of high concentration. It serves to equalize the concentrations in the two areas.
In the case of freshwater fish, their blood and bodily fluids are much saltier than the water they swim in, so water will flow in through their gills. The opposite is true for saltwater fish.
As well as getting water through osmosis, saltwater fish need to purposefully drink water in order to get enough into their systems. Where their freshwater counterparts direct all of the water that comes into their mouths out through their gills, saltwater fish direct some into their digestive tract.
But fishes’ bodies, just like ours, need a certain concentration of salt to function best. They can’t just allow the water to diffuse freely through their gills; the saltwater fish would shrivel up and the freshwater fish would explode!
To stop the exploding fish phenomenon, their gills have special cells that selectively pump salt in, or out of their blood. In freshwater fish, the cells constantly pump salt in, and in saltwater fish, they constantly pump salt out. Saltwater fishes’ kidneys also help to filter out some of their salt.
Want to see osmosis for yourself? Submerge some potato slices in salt or fresh water overnight. The saltwater-soaked ones will still be crunchy, but the freshwater ones, having absorbed water, will be softer.
In short: some, but not all, fish drink. Kind of like how some, but not all, fish… fart.
So, keep in mind that next time you’re preparing your fishes’ tank you’re not only creating his environment but his beverages too.
Female dogs opt for less yoga-like squatting postures than their male companions, who can sometimes be seen with their leg so far in the air they seem about ready to topple over. It turns out that the height to which male dogs raise their leg has a lot to do with their body size, where they are, and who’s around.
All canines use urine to mark their territory, but some do it more than others. All male dogs, big and small, raise their leg to pee or scent-mark much more frequently in the fall than in the summer, likely because it is mating season. Accordingly, the frequency of their urination increases whenever there is a female dog or a male competitor present. Males will sometimes even raise their leg when their bladders are empty, performing what is called a raised-leg display. Females mark their scent much more often when near their nest or den, and males mark theirs more frequently on unfamiliar objects and places.
The height to which they raise their leg also seems to have to do with getting a mate, defending territory, or intimidating other males. Male dogs raised their legs higher when near the edges of their territories, or when they were with their mates. But proportionally, littler dogs raised their leg much higher than their big friends. Perhaps this is their way of making themselves seem larger, like a bettawith its fins or a cat with its fur.
All we know for sure is that they look pretty silly to us.
In the late 1940’s both Soviets and Americans began investigating the expanse of space by sending animals up, up and away. It began with fruit flies in 1947, grew to include monkeys in 1949 and mice in 1950, but no animal actually entered orbit until November 3rd, 1957, when Laika, a Soviet trainedstreet dog, made history.
Sputnik 1 was the first satellite to orbit the Earth, but Sputnik 2 (or more appropriately Muttnik) was the first satellite to reach orbit with a creature aboard.
Laika was found on the streets of Moscow, which meant she was already adapted to survive extreme cold and hunger. She was chosen because she was calm, sweet, and, as a female, could pee with her leg down (this made designing her space suit much simpler). She underwent training like any cosmonaut: centrifuges, confined spaces, loud noise exposure, acclimatization to nutrient gel food and fitting for a space suit. However, unlike modern cosmonauts, her return was never planned for.
According to the Sovietsthe plan was to euthanize Laika with medicated food just before reentry. Sadly this humane method didn’t pan out. Laika’s vital signs stopped after 5-7 hours in orbit.
The Sputnik 2 mission was planned hastily, as then Soviet leader Khrushchev wanted its launch to coincide with the 40th anniversary of the October Revolution. The vessel was built in only about 4 weeks. After news of Laika’s launch spread, the Soviet government alternatively claimed that she had died from a lack of oxygen or been euthanized early. Years later, one of the mission’s scientists admitted Laika had died by overheating due to a mechanical problem in the spacecraft, a much less desirable way to go.
Laika’s flight spawned outrage from animal rights activists the world over. But it also piqued the curiosity of an American army physician, Duane Graveline. His desire to understand how the Soviets had received the biophysical data from Laika led him to research space’s effects on the human body and help develop the technologies that allowed NASA to send astronauts (which he later became!) to space.
I once broke my tooth on some toffee my mom made. Every time I see a beaver, I think of that day and wonder how they can gnaw on trees all day without chipping an incisor when I couldn’t even conquer candy.
Since beavers are rodentsit’s not too surprising that their teeth constantly grow. This allows them to chew away on their sticks while keeping their teeth, but my guinea pigs are also rodents and I wouldn’t put them up against a log.
Beavers have another trick up their pelts though: their enamel. If you’ve ever seen a beaver’s teeth you’ll know that they appear pretty orange. This is because, whereas other rodents have magnesium in their tooth enamel, beavers have iron. So beavers have orange teeth for the same reason we have red blood.
The iron causes the orange colouring in beavers’ teeth, makes the teeth stronger against mechanical stress,and makes them more resistant to acid. Researchers are using these new findings to look at ways of strengthening human teeth, which gives my dreams of candy-conquering new hope.
Rabbits and hares are pretty cute, but they’re also fascinating.
Rabbits’ physiology is perfectly adapted for their needs. Being prey animals, rabbits need to be very aware of their surroundings. Their large ears and good hearing are well known, but did you know they also have vision that encompasses almost 360 degrees? Their eyes are situated high on the sides of their faces, giving them only a tiny blind spot directly in front of them. They even sleep with their eyes open, blinking only their nictitating membranes, or clear third eyelids, to keep their eyes moist.
Even if they can’t see or hear a predator, rabbits can probably smell them. They are obligate nasal breathers, meaning they breathe only through their noses. This way, they can always smell their environment, even when eating.
When they do smell, see or hear a predator, rabbits have to be able to make quick escapes. To help with this bunnies have very large back feet, and hinged skulls to absorb shock. Their cranial hinge allows rabbits to run at speeds above which the impact of their feet would rattle their brain around.
Remember, rabbits might be impressive, but they’re impressively bad Easter presents. Bunnies are the most abandoned pet in North America, and that’s not a statistic you want to contribute to.
Rabbits are foraging herbivores, eating mostly grass and weeds. But this fibrous, cellulose rich diet isn’t the easiest to digest, and by the time their dinner has make it through their intestines it still contains many of the nutrients the bunnies need.
Rabbits and hares beat this problem with a special kind of digestion called hindgut fermentation. In short, they eat their own poop and digest it a second time. Bunnies actually make two different kinds of droppings: little black round ones and softer black ones known as cecotropes that are eaten. This process is known as coprophagy, and functions the same as cows chewing their cud.
It’s very important for a rabbit’s digestive system to keep moving fluidly, as they need to re-ingest their cecotropes in order to get the nutrients they need. If anything gets stuck in a bunny’s esophagus or intestines, they’re out of luck, since they’re incapable of vomiting.