i've read here and there that it's healthy to change a dog's food from time to time, they get more varied nutrients that way and are less likely to develop allergies.
so far, the suggestions/practices i've read about are to change food every few months or each time a bag of kibble is finished.
i'm wondering if it's healthy or harmful to change much more often than that. for a long time, i've noticed that Zack will happily eat a food for a day or two, but then by the third day or so, he will act disappointed at that same food.
For a while, i was switching foods and trying different foods, trying to find something that he would continue to like, but no matter what it was, with the exception of homecooked boiled chicken and rice, he always got disenchanted after one or two days.
thanks to good advice from karlin, i stopped searching for something he would always like and just stuck with one kibble, and he will eat that. After the first day or two, he will not eat it right away but will eat it a little later, or off and on throughout the day til it's gone. i feed him twice a day generally, and he eats eventually even if not for some hours.
recently, for about a week now, i've been switching his kibble every day or even giving him two different kibbles in the same day. After all that experimenting with different foods in the past, i have 6 different kinds of kibble in air tight containers. so, i figured, why not give him variety. The result is that when i give him one that he hasn't had in a few days, he acts happy and eats it readily.
is there any health reason to not vary the food this much? his digestion seems fine, no sign of any problem.