More things we do to animals

In Nutrition & Metabolism class yesterday, we had a brief discussion about the production of urea during the metabolic process. Our instructor then segued into a slightly different topic, starting with a slide showing his beautiful, lush, green lawn. Next slide: pictures of a cute black lab peeing on some grass. Third slide: the instructor's lawn with a bunch of ugly dead spots on it.

A surprising number of people are really concerned about the appearance of their grass, and dog urine, with its fairly high concentration of urea, is pretty good at killing grass. A lot of people blame this on the pH level of their dog's urine, so they try all sorts of home remedies to alkalinize or acidify the urine. Something they unfortunately don't know is that messing around with your dog's pH levels can do bad things like predisposing your dog to urinary tract infections or even bladder stones. What's more, pH levels aren't actually even responsible for urine killing grass -- it's the urea.

So next we talked about different ways to alter urea levels in the urine. One way is by feeding a diet specially formulated for animals in kidney failure. (One of the problems in kidney failure is that certain proteins aren't metabolized efficiently by the body, and urea is formed when the body tries to metabolize the proteins. Normally, the kidney can filter and excrete this urea. But when the kidneys get sick, they can't filter so much urea and it ends up remaining in the blood -- which is why you see an elevated BUN, or Blood Urea Nitrogen level. Anyway, to try to avoid this problem, certain pet food companies have formulated diets that contain types of protein that the animal's body can metabolize efficiently, thus minimizing the amount of urea that is formed to begin with.)

Another thing you can consider is giving your dog a saltier food, or just putting salt on her food. That will make her drink more water, which will result in a more dilute urine so the relative concentration of urea in the urine is decreased. However, the increase in water intake can also increase the volume of the blood, which can be dangerous for some pets, like those with heart disease.

It bothers me a little that people are so concerned about the appearance of their lawn that they would do all sorts of things to their pets just to try to alter the natural content of their pet's urine. It especially bothers me when people make these changes without consulting their vet to find out whether they might actually be harming their pet or predisposing them to disease.

Fortunately -- good instructor! -- we also discussed a couple non-invasive ways to save your lawn. One is by replanting your grass. Apparently certain species of grasses are less susceptible to damage or death by high levels of urea.

But the best strategy, which I think should actually be the first thing that owners try, is to simply train your dog to urinate in a particular place. If Molly pees in the same corner of the yard every time she goes out, that corner will be extra dead and the rest of your grass can thrive. Obviously, this will probably work better for female pets, since males like to wander around and claim every single object as their own. But that same tendency makes males less likely to damage the grass to begin with, since they are only depositing a small amount of urine, and thus a small amount of urea, in each spot.

Or, you could just stop caring so much about your darn lawn. :-)