Q: Which animal has a better sense of smell, dog or cat?
A: Dogs, “by a nose,” and it’s related to physiology.
A cat has something like 50 million to 80 million odor-sensitive olfactory receptor cells in its nose, but a dog (depending on breed, with the bloodhound as champ) has a whopping 200 million to 300 million. We humans only have 5 million or so. The feline sense of smell is roughly 10 to 20 times keener than humans’ — whereas a dog’s nose is tens of thousands times more sensitive than ours.
But a dog’s superlative sense of smell also has to do with structure: The longer snout on most dogs is a masterpiece of evolution when it comes to gathering, sifting and sorting out smells. And dog brains have a much greater olfactory-processing capability than ours. For every one scent we notice, they’re picking up dozens or even hundreds. That’s why dogs can seem so distracted when they go out for walks — they’re literally following their noses!
Q: Is it possible to overfeed tropical fish?
A: Yes. Not all fish eat the same food, so choose the right food for your specific fish. And although fish can only eat as much at one time as their stomachs will hold, many will overeat to the point of obesity.
Tropical fish will typically become full after three to five minutes of eating. After that, surplus food remains suspended in the water and starts decaying, which pollutes and degrades the tank’s closed ecosystem. So overfeeding is not only bad for the fish, it also leads to extra maintenance.
Try dropping food into the tank a little at a time — you can always add more. It’s better for both fish and tank environment to feed small meals at regular intervals during the day rather than dumping lots of food at once.
Observe your fish at feeding times. Different species have different eating habits. If you have more than one type, you can meet their needs by feeding different foods at varying times. To ensure that all the fish are eating properly, you may even have to separate different species at mealtimes. Seeing how your fish behave when fed can also tip you off to any that aren’t eating and might be sick.
Wild fish have the opportunity to sample an assortment of foods. To simulate that natural pattern, alternate or mix dried or frozen food with live food and greens. The right nutritional balance helps keep tropical fish healthy.
David Tayman, D.V.M., has practiced veterinary medicine in Howard County since 1974. E-mail questions to Dr. Tayman at David.Tayman@vcahospitals.com.