Stop having animals in cages

Thousands, if not millions of small and large animals like birds, mice, rabbits, turtles, fish and others are spending their lives in small cages and tanks, being someone's pets. These animals live in very unnatural conditions, with their freedom totally deprived, with no ability to move, eat what they like, mate and reproduce or generally follow the route that nature intended. Providing food and shelter, even if done with the best intentions and with a lot of (human) love, it is never enough for these animals to feel as happy and as "complete" when being in their natural environments with their own species. 
Apart from encaged animals, this is a statement that stands for all pets. Even cats and dogs and farm dogs like ducks, pigs, cows and sheep are entitled to live close to their nature, hence having a pig in an apartment, no matter how much loved and cared for, will never be the same as a pig raised in a muddy open space with other pigs (and some challenges like rain and cold as long as there is shelter around).
Fish may not have brains like humans but being confined to swim around in the same tiny water tank for all their lives, when they are actually meant to do thousands of miles in a lifetime, are deeply depressed and unhappy despite the fact that humans have not yet invented a scale to measure that depression or cannot read the signs of their despair.
Birds singing in small cages when they are actually meant to fly free in the air, built nests, catch warms, reproduce and feed their families, they probably do not sing very happy songs but rather morn for they are likely not finding fulfilement. 
So please ask the EU commission, and all European governments to forbid all animals from being encaged for pets. In a more general form, all governments should provide careful legislation and monitoring of the living conditions of pets. No more farm animals being raised away from spacious farms and open-aired yards. No more birds in cages. No more mice making circles in wheels away from their beloved dark underground tunnels and extended families.
And while we are on that topic, we can also take a moment and think about weather there should be any laws allowing zoos, sea-animal parks and animal-circus too. To make it easier, think about the polar bear, with a fair designed for -30c degrees and a body that needs to walk thousants of miles and dive to ice-cold waters, capable of smelling a wheal underwater from a mile, now spending her days at 10c degrees. In a cage. Next to a hot-dog stand. Could she possibly feel greatful about the same dead fish she its every day?