this is common sence i would think. If you don't take care of
your animal at all it will die. If you give it the wrong food it
will become sick and certain foods can be toxic to some animals
that aren't toxic to us or other animals. Lack of feeding will make
the animal aggressive and will eventially kill it. Not cleaning its
cage means there is dust, dirt, feces, & urine everywhere
causing sickness & w/ the urine & feces there are bacteria
and diseases building up which will make the animal sick & the
buildup of feces & urine will just make your home smell aweful.
Making sure it has bedding will make the cage easier to clean but
use proper bedding for whatever animal it is. giving fresh water
will keep the animal hydrated but make sure animals who need
vitamin C get it which you can purchase vitamin C to add to water
(do not use Juice, there is a product called vitamin C sundrops,
there may be a generic brand but what i am referring to comes from
a company called sunseed) With lack of food there is also attention
and enrichment (play time) that can also make it aggressive if it
doesn't have.