The amount for a cat would easily fit in a capsule. You could prepare a bunch of capsules in advance and them dump them out when needed.
You must have remarkably unfussy cats if they’ll eat food adulterated with niacin.
I had thought of that. Might be tricky telling them apart, but better than what I’m doing now.
The cats in question would eat anything, almost. They’re used to having supplements added. Feeding time is a grand competition, hence the need for separate rooms and areas for each of the 8. And it’s over in less than 3 minutes from the starting bell. ;-)