Report Abuse. You should get them at 8 weeks old. That's an age where it won't be dramatic for them to be without their mother (or at least a caregiver that can take care of them 24/7) and old enough where you can start training. A lot of rescue center won't even give dogs younger than that.Silvia Â· 5 years ago. Thumbs up.eport Abuse. You should get them at 8 weeks old. That's an age where it won't be dramatic for them to be without their mother (or at least a caregiver that can take care of them 24/7) and old enough where you can start training. A lot of rescue center won't even give dogs younger than that. Silvia Â· 5 years ago.
Updated August 04, 2014. You can use a black light to detect body fluids. It's actually a good way to look for pet urine or make sure a bathroom or hotel room is really clean. Cat urine, in particular, glows very brightly under ultraviolet light. Urine glows under a black light primarily because it contains the element phosphorus.
Many more items glow when exposed to black or ultraviolet light. Here is a list of other materials that glow: Petroleum jelly, such as Vaseline, glows a bright blue color under a fluorescent light. (see a photo) uranium glass or vaseline glass. rock salt. fungus that causes Athlete's Foot (supposedly glows orange)